فصلنامه پژوهش های صنایع غذایی
سال بیست و نهم شماره 3 (پاییز 1398)

The oxidation of fats and oils during food processing and storage not only causes loss of nutritional and digestive quality, but also produces compounds such as free radicals that lead to potentially biologically adverse and chemical reactions, Therefore, the use of antioxidants is essential to prevent the onset of corruption. Although many oils contain natural antioxidants such as flavonoids and tocopherols, due to insufficient efficacy of these compounds, they should be added to edible oils (Ibrahimzadeh et al. 2008). Synthetic antioxidants such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), and tertiary butylated hydroquinone (TBHQ) are commonly used to delay the oxidation spoilage of oils (Semnani et al. 2006). extraction and purification of rosemary extract and its extensive supply for nutrition and hygiene as a natural antioxidant (sunjae et al. 2011) or extract of iranian oregano extract and evaluation of antioxidant activity and competition with BHT synthetic antioxidant in sunflower oil there have been some of these efforts (kamkar et al. 2010). Other plant sources that have been studied in recent years for antioxidant compounds in their essential oils or extracts can be found in Laurus nobilis</em> (Inan et al., 2012), Citrus aurantium</em> (Saro et al. 2013), Pulicaria  gnaphalodes</em> (Kamkar et al. 2013), lavender (Tahanjad et al. 2010) and Malva sylvestris</em> (Tahanjad et al. 2012) were noted.In order to investigate the antioxidant potential of the active ingredients in aromatic plants, the present study evaluated the antioxidant properties of the essential oil of Oregano in comparison with the synthetic antioxidant of TBHQ in frying oil stability.

Oregano was collected from the area around Shooshtar in Khuzestan province in mid-autumn and after wash and rinse to remove dust, it was dried at laboratory (temperature 28 ° C and 44% relative humidity) and then 100 g of The dried plant was transferred to a Clevenger apparatus and extracted for 3 hours and then dehydrated with sodium sulfate and stored at 4 ° C. Compounds of extracted essential oil by injection of 0.5 μl Cyclohexane diluted essential oil to Agilent 6890A gas chromatograph containing HP-5 column (30 m length, 250 μm internal diameter and 0.25 μm constant phase thickness) attached to Agilent 59 mass spectrometer is identified. Total phenol content of the essential oil was determined by Folin-Ciocalteu method and its antioxidant activity by DPPH and ABTS tests. Antioxidant activity of oregano essential oil at three levels of 200, 500 and 1000 ppm and TBHQ synthetic antioxidant at 200 ppm in antioxidant-free frying oil (consisting of 60% soybean oil, 40% palm and 100 ppm citric acid) at 90 ° C on days 0, 1, 2, 3, 4, 5 and 6 were evaluated by measuring peroxide value and thiobarbituric acid test.

Based on the results, twenty-two compounds were identified by water distillation. It contained 95.3% of the essential oil. Of these, polygon (31.54%), cineol 1-8 (15.88%), menthofuran (11.8%) and cis iso-polygon (9.74%) constituted the major constituents of the plant essential oil. The results of this study were somewhat different from those of others. The differences in the type of essential compounds and their percentages in the essential oils can be attributed to differences in climatic and plant growth, harvest time, shelf life, method of extraction, and finally genetic variation of the plant. Each gram of oregano essential oil contained 7.5 mg phenolic compounds based on gallic acid on dry matter. There was a direct relationship between the essential oil concentration and its DPPH scavenging effect. The EC50 index of oregano essential oil was 1 mg / ml. Radical inhibitory power of oregano essential oil was compared with synthetic antioxidant TBHQ and the results showed that oregano essential oil at a concentration of 1 mg / ml had inhibitory power equivalent to 0.06 mg / ml of TBHQ antioxidant. Based on the results and comparison of EC50 essential oil with those investigated by other researchers, it is clear that the essential oil has good antioxidant activity and has good antioxidant activity compared to other antioxidant sources. There was a direct relationship between the essential oil concentration and ABTS radical scavenging ability. Evaluation of antioxidant activity of essential oil in fried oil for 6 days at 90 ° C in terms of peroxide and thiobarbituric acid values showed that Peroxide value was dependent on the concentration of treatments and decreased with increasing concentration of treatments and hence there was a significant difference (P<0.05). On the other hand, no significant difference was observed between the concentrations of 500 and 1000 ppm (P<0.05). In the first days of the test, concentrations of 500 and 1000 ppm of Oregano essential oil and TBHQ antioxidant reduced the same amount of peroxide but were weaker than TBHQ antioxidant on day 4 and reduced peroxide to a lesser extent. The concentration of 200 ppm essential oil from day 4 did not show any significant difference with control. Concentration of 500 ppm of Oregano Essential Oil during the Test with TBHQ Antioxidant Reduced Thiobarbituric Acid. The results of this study showed that Oregano essential oil has high potency in inhibiting DPPH and ABTS radicals and in terms of changes in peroxide and thiobarbituric acid during storage under oxidation conditions and the effect of essential oil concentrations in comparison with synthetic antioxidants. The results of this study indicated that oregano essential oil can be used as a replacement for synthetic antioxidants in oil and in addition to eliminating synthetic antioxidants, which can cause cancer by accumulating in tissues and organs, enhancing the thermal stability of the oil without causing undesirable changes.

Different concentrations of oregano essential oil showed antioxidant activity and decreased oxidation rate. Volatile compounds, although they play the most important organoleptic role in oils, have a negative effect on the sensory properties of the product during frying and over time, possibly due to oxidation and formation of substances. It produces a bad taste and smell. Also, because of its ability to react with oxidation-induced radicals, this essential oil can be used as a natural antioxidant in food products, especially fatty foods and prolong their shelf life. In addition, natural antioxidants are safe and beneficial to the consumer

Probiotics are living organisms that, if consumed in the necessary amounts, have health effects on the host's body. The importance of these microorganisms and their health-promoting properties has led to the growth of new useful products including probiotic products (Wohlgemuth et al., 2010). Probiotic bacteria are defined as live microbial dietary supplements that can usefully modify the microbial balance of the host intestine (Durack et al., 2018). Enterococci are commonly found in raw milk and traditional fermented dairy products, and milk is an ideal source for the growth of these organisms (Doming et al. 2003; Švec and Franz 2014). Many species of Enterococcus have proteolytic and lipolytic activity and cause special taste and aroma in traditional cheeses; moreover, some Enterococcus strains have the ability to produce bacteriocin during against pathogenic bacteria such as Listeria monocytogenes, Staphylococcus aureus, Vibrio cholerae, as well as Clostridium and Bacillus spp. These characteristics make Enterococci to be considered as a good probiotics candidate; however, they have not yet obtained the status GRAS (Generally Recognized As Safe). Consequently, the presence of Enterococci in dairy products may be hazardous while being useful (Ogier and Serror, 2008). According to previous studies, different species of bacteria have been introduced as probiotics, but most of the introduced probiotics belong to the genus Lactobacillus and Lactococcus. In this regard, some studies have been done on some traditional Iranian dairy products (Narimani and Tarinezhad, 2014) and less attention has been paid to Enterococcus genus, especially native strains isolated from traditional products. The aim of this study was to isolate and identify Enterococci from raw milk and traditional dairy products in Tabriz region and to evaluate their probiotic potential.

 Enterococci were isolated by culture method and identified by biochemical tests. For this purpose, 10 g of the sample was mixed with 90 ml of sterile Ringer's solution and placed in a 40 °C water bath for 5 minutes. It was then homogenized by a shaker at 230 rpm for 2 minutes (Koluman et al., 2009). Afterward, 100 µl of the suspensions (and in the case of buttermilk, 100 µl of non-diluted sample) were cultured on Kanamycin Aesculin Azide agar. Cultures were incubated at 42 °C and aerobic conditions for 24-48 hours (Doming et al. 2003). Colonies 1-2 mm in diameter with black halo were selected and cultured on Brain Heart Infusion agar plate (37 °C for 18-24 h) for morphological and screening assays (Garcia-Cano et al., 2014). Since the purpose of the study was to evaluate the probiotic potential of the isolated Enterococcus spp., the species diversity and the source of the isolates (type of dairy product) were considered as the criteria for selection of the strains. Probiotic properties such as acid and bile tolerance, proteolytic and lipolytic activity, susceptibility to antibiotics and virulence factor genes were investigated.For acid resistance, Enterococcus isolates were cultured in MRS broth (24 h, 37 °C) and then precipitated at 4 °C for 4 min at 4,000 g. 0.1 ml of the precipitate was added to the tubes containing 2 ml of sterile PBS at pHs 1, 2 and 3 (using hydrochloric acid) and mixed. The tubes were then incubated at 37 °C for 120 minutes. Serial dilutions of the samples were prepared and the populations of the survived Enterococcus species were counted at 0, 30, 60 and 120 minutes of incubation using the plate count method. The resistance of the isolates to bile salts was evaluated in broth medium containing 0.1, 0.2, 0.3 or 0.4% bile salts, followed by incubation at 37 °C for 24 h (Lee et al. 2015). For proteolytic and lipolytic activity, the isolates were cultured on Skim milk agar (at 30 °C for 6, 24 and 48 hours and then at 10 °C for 7, 15 days) and Tributyrin agar (for 5 days at 30 °C), respectively (Serio et al. 2010). The antibiotic resistance pattern was conducted by disk diffusion method. The presence of virulence was exploited using PCR assay to detect Esp and Asa1 genes (Wankerwon et al. 2004).
 

Various species of Enterococcus were isolated from the tested specimens, among which E. faecalis and E. faecium were more abundant. Therefore, 24 isolates consisting of 6 isolates of E. faecium, 5 isolates of E. faecalis, 4 isolates of E. gallinarum, 2 isolates of E. casseliflavus, 2 isolates of E. avium, 2 isolates of E. mundtii and 1 isolate from each species of E. hirae, E. saccharolyticusand E. raffinosus were selected for evaluation of probiotic potential. Based on results, none of the Enterococcus species tolerated pH= 1 and 2; however, all of the isolates survived pH= 3 during the 30, 60 and 120 minutes of incubation. Bile tolerance assay revealed that all the species were resistant to 0.1%, 0.2%, 0.3% and 0.4% of bile and their population was reduced along with the increasing of bile concentration. Moreover, various degrees of proteolytic and lipolytic activities were recorded for the different species and also among strains of individual species. The highest proteolytic activity was observed after 15 days in E. faecalis, E. mondetii and E. hirae; meanwhile, the highest lipolysis activity was found for E. saccharolythicus, E. casseliflavus and E. faecalis. In addition, different degrees of sensitivity was observed in the antibiogram assay. Esp gene was traced within two E. faecalis strains; however, Asa 1 gene was not observed among E. faecium strains.

Based on the findings of the current study, it can be concluded that raw milk and traditional dairy products are a rich source of Enterococcus species that are highly resistant to acid and bile. In addition, most of the isolates tested have proteolytic and lipolytic properties and can, therefore, contribute to the development and development of flavor in traditional fermented products such as cheese. The resistance of Enterococci to different antibiotics indicates the ability of these strains to survive in the gut if antibiotics are used. However, these data need to be interpreted more cautiously, as over-resistance to antibiotics is not an advantage and may have limitations in the selection of these strains. Finally, lack of Esp virulence gene in most isolates of E. faecalis and lack of Asa 1 virulence gene in E. faescium can be a positive sign of non-pathogenicity of these strains, explaining that one or more virulence factors should not be sufficient in Enterococcus. All virulence genes in Enterococcus are identified and studied in isolates of this bacterium. It can be concluded that Enterococcus species could be considered as potential probiotic bacteria, but it is crucial to conduct precise molecular, cellular and animal model investigations in order to assess the safety features of enterococci.

In recent years, Nanoscale composites have been considered for excellent physical, mechanical and electrical properties, such as extensive flow, catalytic activity, and more. Super paramagnetic nanoparticles based on magnetite (Fe3</sub>O4</sub>) have exhibiting striking characteristics, such as large surface area, mobility, and high mass transference. More than that, they can be easily recovered by applying an external magnetic field. In this study, zeolite micro particles with large internal contact surfaces and iron oxide nanoparticles were linked to each other by covalent technique then both were coated via CMC (Carboxy Methyl Cellulose) with the mixed-matrix method. The most important features of zeolites are: regular and uniform pore system and high ion exchange capacity, a large surface area, non-toxic and safe for environment (Nabiyouni et al. 2015). CMC is natural polyanion that have the features such as the ability to provide good films and mechanical resistance and it is augmenter of electron transfer (Cheng et al. 2013; Cui et al. 2011). The produced nanocomposite was designed as a support for the chemical alpha-amylase immobilization, and the loading efficiency calculated by Bradford reagent and UV-visible spectrophotometer and immobilization efficiency by the Miller method (Starch hydrolysis and optical absorption measurement of maltose produced) were calculated. The mechanical and electrical properties of nanocomposite film were also studied by Four probes device.

 A commercial enzyme α-amylase (from Aspergillus oryzae, 30 U/mg protein), sodium salt of CMC (high molecular weight), phenol and sodium potassium tartrate were obtained from Sigma-Aldrich. Fe3</sub>O4</sub> nanoparticles were obtained from Nanosany Corporation (Mashhad, Iran). Na A- zeolite was obtained from Kimia Khatam knowledge-based Co. (Tabriz, Iran). 3-Aminopropyl-trimethoxysilane (95% purity) (APTMS), Glutaraldehyde (25% aqueous solution), soluble starch and 3,5-Dinitrosalicylic acid (DNS) were obtained from Merck Chemicals (Darmstadt, Germany), All other materials were commercially accessible and they was used without any purification. The bonding of zeolite and iron oxide was done by a trimethoxysilylpropylamine solution, which was used to modify and bond simultaneously iron-zeolite magnetic nanoparticles. The modification and actuation of zeolite surface were performed by Fe3</sub>O4</sub> and APTMS as the silane-coupling agent, respectively. In brief, a zeolite with a particle size of 1 to 2 micrometers and magnetite nanoparticle (10: 1) was immersed in 20 ml of toluene solvent. Then the mixture was dispersed in toluene for 5 min using probe-type sonicator (70w, 0.5 Hz), followed by addition of 1ml APTMS solution to the mixture for bringing the amino groups on the surface of zeolite and Fe3</sub>O4 </sub>(Hosseinipour, Khiabani, Hamishehkar & Salehi, 2015). The mixture was refluxed at 110  for 3 h to induce the surface hydroxyl groups of zeolite. The synthesized iron-zeolite was mixed with a good percentage of CMC plus 2% glycerol to prepare the film. To investigate the surface properties and scanning electron microscope particles, for the interaction of components the infrared spectroscopy and to study an X-ray diffraction the structure of crystalline materials was used. Mechanical properties were also obtained by a tensile and stress device, electrical properties such as I-V curve; electrical conductivity and electrical response stability for Nano composite film were obtained using a four-point probe. The surface of the support was active by glutaraldehyde (25%) and within 24 hours on an orbital agitator, immobilization the enzyme was performed. The loading efficiency was calculated by measuring the amount of unsaturated protein by Bradford Reagent and the Uv-visible spectrophotometry. The immobilization efficiency was calculated by measuring alpha-amylase activity by miller method (starch hydrolysis and optical absorption measurements from maltose production).

The results of scanning electron microscopy showed that magnetic iron nanoparticles were bonded to each other by trimethoxysilyl propyl amine and made iron nanowires. Then, the same binder binds the nanowires to the zeolite microparticles. Iron nano-wires are also embedded in the zeolite microparticles and the bonding is well established. Interpretation of particle size revealed an average size of iron nano-diameter of 48.8 nm. The results of FTIR showed that the peak in the wave number of about 554 cm-1</sup> indicates the Fe-O groups present in the iron nanoparticles, which confirms the binding of the iron nanoparticles to the zeolite. But in this study, nanoparticle bonding cannot be ensured because of the overlap with the Si-O-Al peak in the zeolite structure. Therefore, X-ray diffraction (XRD) test and absorption test by external magnetic field were used to confirm the binding of iron magnetic nanoparticles to zeolite. Zeolite is known as a crystalline material while magnetic iron nanoparticles have more amorphous portions. As a result, the interference of the waves in the zeolite-iron oxide nanocomposite was of a destructive type. In result of XRD test a reduction in the crystalline peak in magnetized zeolites observed that confirm the binding of iron magnetic nanoparticles to zeolite. In the mechanical test of final tensile strength, the maximum elongation, elastic modulus and strain to breaking point were 1.31 MPa, 13.72 mm, 3.95 MPa and 34.31%, respectively. Electrical properties of nanocomposites were measured using a four-probe device. The potential-intensity difference curve was non-linear, indicating the semiconductor nature of the nanocomposite film. The electrical conductivity was calculated at 1 v potential difference and 0.1 mA current equal to 0.053 s / cm and the amperometric response was observed at 450 s for about 2.5 μA. Loading efficiency by Bradford method and immobilization efficiency by Miller method were 93.2% and 82%, respectively.

 Comparison of the electrical and mechanical properties of the nanocomposite film with other studies showed that the mechanical properties of the prepared film and the electrical properties of this film are very suitable for use in biosensors. Also, due to the high loading efficiency and high enzyme immobilization efficiency, the potential of the synthesized nanocomposite support was found to be very desirable. Isolation of the substrate by an external magnetic field in the immobilization of biological molecules and use as a drug carrier (for example, the zeolite carrier for the anti-cancer drug 5-fluorouracil) is of great intereste.

 Bread is an important part of the Iranian families' diet. Due to the ease of mold growth, especially Aspergillus flavus </em>on raw materials, it is possible to produce aflatoxin from these types of molds on the bread. The production of Mycotoxins in foods and feeds is a problem of major concern in all over the world. So, the most important microbial concern and challenge associated with bread are fungal infections and their toxins such as aflatoxins that include G2, B2, B1, and G1. There are several ways to reduce aflatoxin from foodstuffs including physical methods (cleaning, heating, radiation) chemical methods (chemical compounds, ozone gas) and biological methods (using bacteria, yeasts). Also, various studies have shown that the best and most reliable method for detoxification of contaminated foods with mycotoxins is the use of effective microbial species, such as Saccharomyces cerevisiae</em>, which is an essential ingredient in the formulation of breads. Saccharomyces cerevisiae</em>, also known as ‘’baker's yeast’’, is one of the most widely commercialized species and one of the effective adsorbent, rich in protein (40-45%), whose biological value is high and is also rich in vitamin B complex. This microorganism is used as active dry yeast in baking, which does not require refrigeration and had a longer shelf-life and better temperature tolerance than fresh yeast that would rise twice as fast, cutting down on baking time. The optimum temperature for growth of S. cerevisiae is 30–35 °C. With the respect that wheat in the silage during storage may be subjected to optimum temperature and humidity, conditions which is favorable for the growth of fungi and aflatoxin production in flour and bread, so S. cerevisiae can be used in baking for detoxification (via surface adsorption) and generating the carbon dioxide by the fermentation which is used as a leavening agent in bread and other baked goods. The leavening step is an essential stage in the fermentation of dough. S. cerevisiae does not only induce and increase the volume of dough through gas incorporation but helps creating the desired flavor and texture. Also, Saccharomyces cerevisiae</em> is used as a probiotic in humans and animals. Especially, a strain Saccharomyces cerevisiae var. boulardii </em>is industrially manufactured and clinically used as a medication. Investigations confirm that Saccharomyces cerevisiae var. boulardii</em> is effective in reducing the risk of antibiotic‐associated diarrhea in children and adults.
So, the aim of this project is to investigate the effect of traditional fermentation, conventional baking and IR baking methods on the rate of aflatoxin reduction in lavash bread.

In this research, the effect of instant yeast of bread was investigated on the reduction of aflatoxin during fermentation of Lavash bread dough at 28 Degree Centigrade for 1 hour. For this reason, 100 kg of flour with 100 kg of water, 2% salt and 1.5% yeast were mixed for about 5 minutes until became uniform dough, then fermented at 28˚ C </sup>for 1 hour Afterwards covered with a translucent cloth, and allowed secondary fermentation was occurred for 2 minutes and then followed by baking in the oven for 25 seconds at 200 degree centigrade as Iranian National Standard No. 5 procedure. Besides, the performance of the infrared Turbo wave device was compared to conventional method for reducing the amount of total aflatoxin during the baking of the lavash bread.

 The results showed that the amount of reduced total aflatoxin in the fermented samples was 87.4% compared to the control samples before fermentation. Also, the effect of Lavash bread baking methods by infrared and a traditional manner showed 90.33% and 89.95% on the reduction of the amount of total aflatoxin respectively. It can be interpreted that Saccharomyces cerevisiae</em> changes the structure of aflatoxin with its degrading enzymes such as acetyltransferase</em> and reduces its toxic properties. Also, due to the presence of beta-glucan and manan as the binding agents in the cell wall of Saccharomyces cerevisiae</em>; it is able to attach these kinds of toxin molecules to its cell wall and block them. Also, yeast can be effective in adsorption the aflatoxins to its cell wall which in the baking stage, due to the denaturation of yeast cell-wall proteins, the absorbed toxins on the yeast cell surface decomposed and destroyed under the heating action.

 It can be concluded that fermentation is a necessary stage in the production of breads to create a good quality from the point of good texture, organoleptic concern, extending the shelf life of food product and ensures the safety of the bread and health of consumers. Because fermented bakery product has shown that has not toxins in higher amount than standard limit and Mycotoxins due to fermentation decomposes. On the other hand, baking can also decompose Mycotoxins structures. There are many kinds of baking machines which has different effect on the bread quality. So, new technologies such as infrared radiation helps to rapid heat transmission in baking stage therefore, it may influence on the fast degradation of toxic compounds. In this article in addition of investigation on fermentation effect on decreasing Aflatoxin amount, the conventional method of baking compared with Infra-red baking effect on omitting Aflatoxin compounds. But we found that although the amount of Aflatoxin in irradiated baked bread is lower than conventional baked bread, statistically the effect of baking method with infrared rays and conventional methods has similar effect for the destruction of aflatoxin in bread. Therefore, in spite of other differences between Infrared method and conventional method of baking, they do not differ in their effects on destruction of Mycotoxin among baking stage. As a result, the fermentation process with the active bread yeast function among suitable time and temperature plus baking stage can guarantee the health of bread.

Food science has meet new challenges in food production that could respond consumer’s tastes and at the same time improve. Lifestyle modifications related to change in the eating quality and quantity along with mental stress led to the prevalence of non-communicable diseases. Based on the consumer’s demand, food scientists are now focusing on developing low-calorie/high-fiber functional foods. Biscuit is one of the bakery products that is used widely through stratum. Approximately 100-gram biscuit contains 77-gram carbohydrate, 8-gram protein and 13.5-gram fat and produce 465 Kcal energy. Sugar is one the most important ingredients in biscuit formulation and possess the highest amount in formulation after flour and has a major role in creation of a desirable sweet flavor, obtaining moisture, creation of texture, reduction in retrogradation and increase in shelf life of the product. However, sugar has a lot of harmful effects such as diabetes, tooth decay, obesity and cardio vascular diseases. So decreasing sugar content in food formulation is very vital. Considering key role of sugar, a proper substitute should be selected so that quality characteristics of the product maintained. Stevia has sweetening amount about 300 times than sucrose because of its diterpenoid glycosides. Sugar alcohols or alditols such as sorbitol and erythritol are poly-ols that can be used in food formulations as low-calorie low- digestion sweeteners. Regarding use of biscuits a serving in food regime due to high nutritional value and importance of presence of different dietary biscuits relative to different tastes in food basket and the advantages of reducing sugar in food habits, so production of low calorie biscuit using sugar alditols is the main aim of current research.

In current research wheat flour was purchased from Behnam factory from Torbat- e Heydarieh. Erythritol were used as sugar replacer and was obtained from Iran Stevia Company, Tehran, Iran. All biscuit dough’s were produced in a way that ratios were as: four 300 gr, sugar 75 gr, confectionary oil 64.8 gr, water 34.8 gr, invert sugar 24.9 gr, baking soda 3 gr, ammonium bicarbonate 3 gr, lecithin 3 gr, egg 24.9 gr and different substitution levels 25, 50 and 75 (%) of erythritol that was substituted with sugar in the mentioned formulation. Biscuits were produced according to Vatankhah et al. (2014). Biscuits were analyzed for color indices (Francis, 1998), moisture, ash, sugar, weight and volume (Lin, Hwang and Yeh, 2003) and aw content (Zoulias, Piknis and Oreopoulou, 2000). Textural attributes (Savitha and Indrani, 2008), sensory properties (using hedonic scale) and density of product were also evaluated.

According to the results obtained with increasing substitution level up to 25% aw content increased that the highest amount of aw between samples related to the one containing 25% erythritol. The preseason of lower aw content for control sample was due to the high hygrosopicity of sucrose (Wetzel, Weese and Bell, 1997). Increasing substitution level led to decrease in weight of samples. Decrease in weight of erythritol samples compare to control one is due to lower molecular weight of erythritol in compare to sucrose and other sugar alcohols. Results of volume analysis revealed that increasing in erythritol caused an increase in volume of biscuits. The highest amount was for 25% substitution and the lowest one related to control biscuit. This increase is related to texturizing and bulking agent of poly ols. Regarding the reverse relation between density and volume, lower apparent densities in higher volume samples seems to be ideal. According to the results moisture content increased with increasing the substitution level. Moisture content of a product is directly related to molecular weight, hydrophobic interactions, hydrophilic associations and the number of bonds (Rosell, Rojas and Benedito, 2001). Totally increasing in erythritol content in formulation did not affect ash content among biscuits and ash content didn’t significantly changed, which is due to similarity in oil and flour type and content (Pasha, Butt, Anjum and Shehzadi, 2002). As was expected sugar content of biscuits decreased with increase in substitution level, that the highest sugar content accounted for control sample and the lowest amount was for the sample containing 75% erythritol. Decrease in colour attributes of biscuits produced with erythritol in decrease in L* indices was related to not incorporation of poly ols in Maillard browning reaction and or caramelization reactions as well due to lack of carbonyl groups (Ronda, Gomez, Blanco and Caballero, 2005). Findings of statistical analysis related to textural attributes was demonstrating the decrease in the textural parameters by increasing substitution level in biscuit formulation that led to improve in texture of biscuit samples. Texture hardness is highly related to bonding ability of water in sugar alditols and it’s retaining during storage and also the interactions of these sugars with starch that may affect to starch retrogradation (Ronda, Gomez, Blanco and Caballero, 2005). Also, presence of alditols created a smoother texture that is highly related to more bonding with water (Ronda, Gomez, Blanco and Caballero, 2005). Results of overall acceptability revealed that biscuits substituted with erythritol obtained higher scores through sensorial properties.

Therefore, it can be claimed that erythritol can be used in biscuit formulation as a suitable sugar substitutes. Furthermore, sucrose substitution with this alditols will lead to a conspicuous decrease in total sugar content of samples, and lead to improvement in sensorial properties and textural attributes of biscuits compare to the control ones. So this alditols can be suggested to be used as a sweetener and profit flavoring agent in biscuit formula

 Evaluation of the physicochemical properties of fruits during different stages of maturity is essential for achieving high-quality product and extending shelf life. Harvest maturity and storage time are main factors that may lead to changes in sensory and nutritional qualities of cornelian cherries. Cornelian cherry fruit are frequently harvested at dark red stages, when their flavor is most desirable. Consumers do not usually eat cornelian cherry at any of the other maturation stages. Therefore, the effect of ripening and storage time on nutritional quality is a major issue. The cornelian cherry fruits which have sour and sweat tasting juice, contain a high amount of vitamin C. To optimum threshing performance, processes of pnematic conveying, storing and other processes of cornelian cherry fruits, its physical properties should be known.  </strong>

This research was conducted to investigate the effect of harvest time at two stages (commercial harvest and 5 days after the first harvest) on some of the physicochemical properties of a commercial genotype of cornelian cherry fruit during the storage period. The fruit kept in cold storage at a temperature of 4 °C with relative humidity of 80-85% for 21 days. Fruit qualitative traits such as pH content, total soluble solids (TSS), titrable acidity (TA), TSS / TA ratio, vitamin C, ion leakage and ethylene production of fruits during storage at 0, 7, 14 and 21 days of storage were evaluated. Total soluble solids were determined by a hand refractometer (model Atago N, Japan) having range of 0-32 percent and the values obtained in per cent were correlated at 20ºC. Titratable acidity was determined by taking a known weight of fruit juice and making a known volume of it by adding distilled water. Then a known volume of this liquid was treated against 0.1 N sodium hydroxide at pH 8.2 as an indicator of titration using pH meter. The ascorbic acid (vitamin C) content in the aqueous supernatant of each maturity stage was determined.

The results showed that the harvest time has not a significant effect on pH and ion leakage of fruits. The delay in the harvest time increased the total solids soluble solids to total acidity ratio (TSS / TA) ratio and decreased total acidity (TA). However, there was a significant difference during storage period in all of the studied parameters. With progress in the maturity stage and fruit during the storage period, total soluble solids (TSS) and ethylene production in second harvest fruits showed an increase comparing the first harvest time. The increase in soluble solids content of fruit during storage period could be related to conversion of insoluble carbohydrates to soluble ones and decreasing of transpiration of fruit during storage period (Miaruddin et al. 2011). pH, total soluble solids to total acidity ratio (TSS / TA), and ion leakage of fruits increased, while the total acidity content decreased along with storage time. During ripening period of strawberry, the content of organic acids in fruit reduced and soluble sugars increased which led to increasing soluble solids content to total acidity ratio and sweeter fruit taste (Winardiantica et al. 2015). Foliar application of salicylic acid with high concentrations (2 mM) increased fruits phenol content, vitamin C, TA and total anthocyanin compound. Maximum amount of total antioxidant has been established in 2mM SA concentration that demonstrated 18% increase in compare with control. SA foliar application caused to decrease of total soluble solid (TSS) content but had not any significant effects on flavonoid and total carotenoid of grape berries. These results further indicated that the effects of Salicylic acid in grape is associated with induce defensive systems and increase biological performance such as antioxidant activity and different quality fields in grape (Ghohari et al. 2018). The content of vitamin C (ascorbic acid) of the first harvest had lower than second harvest and showed a declining trend for both of them during storage period. Many pre- and postharvest factors influence the vitamin C content of horticultural crops. Large genotypic variation in vitamin content, climatic conditions and cultural practices, Maturity at harvest, harvesting method, and postharvest handling conditions also affect the vitamin C content of fruits and vegetable (Gordon et al 2012). Chaudhari et al. (2017) reported that the ascorbic acid content of citrus fruit decreased during storage period which may related to chilling injury incidence of fruits. Membrane ion leakage of cornelian cherry fruit increased by the end of storage period which led to water soaked fruits. By the end of storage at cold temperature membrane leakage percent of both harvests increased. This may be caused by cold stress oxidative injury effect on fruit cells and softens their texture. Antioxidant activity was high in fruits and varied greatly among the genotypes. So cornelian cherry could be considered a good source of natural antioxidants. They can potentially be used in food and nutraceutical supplement formulations as well. Fruit weight, soluble solids content and acidity were varied significantly among genotypes.  Shewfelt and Purvis (1995) demonstrated that membrane ion leakage in plants could be an indirect signal of membrane integrity state which decreased by the chilling injury incidence in fruit during cold storage period. During storage period, ethylene production of both harvested fruit were increased as the values for first harvest were lower than second harvest. The increase in ethylene production may be related to the effect of cold temperature stress during storage period and change the fruit metabolism as pheylpropanoid pathway (Yung and Hoffman 1984). Ripening and senescence involve the last phase of molecular and biochemical changes that result in the transformation of fruits into an edible form with aesthetically superior organoleptic and nutritional qualities. These changes are initiated in response to ethylene.  

 Generally, our results showed that with delay in harvest soluble solid content of fruit increased and total acidity of fruit decreased. Also, fruit of second harvest had more ascorbic acid content than first harvest that a good qualitative index as an antioxidant compound in cornelian cherry fuit for having a good quality fruit by the end of storage period. So the second harvest fruit was more qualitative than first harvest during storage period.

Kombucha syrup is obtained by fermentation of tea and sugar and the symbiotic coexistence of acetic acid bacteria and yeasts (Santos-Jinor et al. 2009). Kombucha syrupis considered as product with probiotic and functional properties. The health benefits of Kombucha syrup include boosting immune system, increasing digestion, cancer prevention, fat, blood pressure and cholesterol reduction, prevention of heart disease, treatment of fatty liver, reduction of diabetic symptoms and weight loss (Dufresne and Farnworth E 2000). Kombucha syrup can be used in some other types of tea or soft drinks such as coca, whey and lactose (Lončar et al. 2006). Spasenija et al. (2012) investigated the possibility of cultivating Kombucha with two types of black tea and thyme tea in combination with probiotics for fermenting milk at different temperatures. The results showed that inoculation of Kombucha culture with different types of tea in combination with probiotic starter culture can be used for milk and fermented products. Since the microorganisms present in Kombucha are highly beneficial and resistant especially in acidic conditions, they can replace harmful microorganisms in the gastrointestinal tract. Therefore, Kombucha beverage can be considered as a probiotic and functional product (Dufresne and Farnworth 2000). Regarding the benefits of Kombucha syrup for consumer’s health, the aim of this study was to evaluate the effect of Kombucha syrup on the survival of Bifidobacterium bifidum</em> as well as quality of Doogh during storage.

Kombucha syrup was prepared by method described by Blanc (1996), and added to Doogh in the level of 0-20%. Doogh was prepared by the method described by EbrahimzadeganandZomorodi (2014). Then Doogh samples were kept at 4°C cold room for 41 days and were analyzed at intervals of 5, 23 and 41 days during storage. Count of bifidobacterium</em> was performed in RCA agar culture medium under anaerobic conditions prepared by gas pack A in anaerobic jar and incubated at 37°C for 72 hours (Krasaekoopt et al. 2003). The pH was measured using a digital pH meter calibrated with commercial buffers of 4 and 7, dry matter was obtained by drying the samples in oven at 103 ± 2°C until a constant weight, density was measured using a picnometer (National Iranian Standard No. 2453) and syneresis of Doogh determined by the method descirbed by EbrahimzadeganandZomorodi (2014). The color evaluation of the samples was determined by determining colorimetric factors including b*, a*, and L* using digital colorimetric method and image J software (Zomorrodi, 2012). The overall acceptance of the samples was determined using consumer liking and preference experiment and 5-point Hedonic method by 15 trained panelists. For this purpose, the score of 5 represented the desirable quality and 1 indicated undesirable quality (EbrahimzadeganandZomorodi 2014).

 According to Fig.1, the number of Bifidobacterium bifidum</em> bacteria increased by increasing Kombucha syrup and decreased during storage time (P <0.05). The reason for the increase in the survival of Bifidobacterium bifidum</em> by increasing level of Kombucha syrup can be such justified that during the fermentation and oxidation process of Kombucha syrup, the fungi and yeasts consumed sugar, and produced valuable substances such as glycerol, some B group vitamins (B1</sub>, B2</sub>, B6</sub>, B12</sub>) and vitamin C, some minerals, amino acids and other products (Jayabalan et al. 2014). Probably, some of these compounds, including vitamins and amino acids, have been caused to maintain survival of probiotic bacteria in Doogh (Gomez and Malcata 1999). The reason for the decrease in probiotic count during storage can be attributed to more sensivity of this genus to oxygen, high acidity and low pH, the need for growth supplements, namely small molecules organic nitrogen and vitamins, as well as, the need for low reduction potential (Krasaekooptet al. 2003). Vinderolaet al. (2002) reported that pH 4.5 or less had a negative effect on the survival of bifidobacteriumbifidum</em> in yogurt stored at of 5 °C, which is in consistent with the results of this research. According to the recommendation of the International Dairy Federation, the number of live and active probiotic bacteria at the end of the expiration date of the product must be at least 107</sup>Cfu/g. Also, by increasing the level of Kombucha syrup, the dry matter and specific gravity increased significantly (P <0.05). This is due to the high brix of the Kombucha syrup. Spasenija et al. (2012) reported that the viscosity of fermented milk produced with Kombucha syrup made of black tea was significantly higher than that of control sample. These results show the positive effect of black tea ingredients on sample gel during storage. Syneresis of Doogh decreased with increasing Kombucha syrup level (P <0.05). Wu et al. (2013) reported that the Kombucha fungus is able to produce exopolysaccharide. Therefore, increase of dry matter of Doogh due to the increasing Kombucha syrup level and the presence of exopolysaccharides in the syrup, is the reason of the syneresis reduction in Doogh. Also, with increasing kombucha syrup level, the pH decreased (P <0.05). Because in this research the pH of kombucha syrup was about 2.89. The pH reduction can be due to the increased concentration of acetic acid and a small amount of lactic acid, gluconic and glucuronic acids produced by bacteria and yeast in tea fungus (Sreeramulu et al. 2000). Also, due to the use of black tea in the production of the kombucha syrup, addition of this syrup to Doogh, caused to decrease yellowness and to increase redness. On the other hand, Kombucha syrup had no negative effect on overall acceptance score of Doogh.

 According to the experimental model obtained by the response surface method, the correlation between the studied variables detected appropriate. The results of this research showed that, the optimum points for production of Doogh was determined kombucha syrup level 20% and storage time 23 days. In optimum conditions, the number of Bifidobacterium bifidum</em>, 7.6 log cfu/g, specific gravity, dry matter, syneresis and pH were 1.025, 8. 21. 29% and 3.95 respectively. The score of overall acceptance was 4.5 of 5.

The physio-chemical properties of lemon fruits are influenced by climatic conditions, growth stages and shelf life. Lemons mostly cultivated in the south of Iran and is limited in the north due to the cold condition that may be occurred every year. With the expansion of lemon cultivation in the north of Iran specially under protective condition (greenhouse), many of fruit physicochemical properties such as water percentage, taste, skin color, ripening time and bioactivity may be affected by climatic conditions, growth stages and shelf life. The nutritional value of fruit depends to amount of compounds with antioxidant properties. Today, consumers prefer consumption fruits with high bioactive compounds. The quantitatively and qualitatively of these compounds may be changed during ripening or after harvest. In general, fruit peel contains higher concentrations of antioxidants. The peel forms half of the fruit weight and is rich in natural antioxidant compounds such as phenols and flavonoids (Tumbas et al., 2010). Lemon fruit is a good source of vitamins and antioxidant compounds (Qasemi et al., 2011). Because of no comprehensive research has been done on quality changes of lemons during ripening and storage in northern conditions, Therefore, this study was carryout to evaluate the bioactive compounds and physicochemical properties of Lisbon and Eureka lemons at different harvesting times to determine the appropriate harvesting time and prevent frost injury risk.

In this study, the physicochemical and bioactive properties of Lisbon and Eureka lemons were evaluated during two years (2015-2016) by sampling from 17th</sup> October to 16th</sup> November, 10 days interval (four times) from trees and at the end of shelf life period. The location of sampling was Kotra Research Station that was located at the Citrus and Subtropical Fruits Research Center with geographical coordinates of 36 ° 42'47.7 "N 50 ° 58'25.6" E. Fruits were randomly selected from different sides of the tree (30 fruits picked from three trees). 15 fruits were evaluated at harvest time and the others were stored in common storage (7-10 ° C, 85% humidity) and evaluated 20 days after harvest. Various physico-chemical characteristics evaluated including fruit length, width, thickness; arithmetic, geometric, equivalent and harmonic diametric means; aspect ratio, sphericity, surface area, true volume, apparent volume, volume error, density, peel thickness, weight, juice and residue percentage, peel color indices (L*</em>, a*</em>, b*</em>, hue angle, chroma and CCI), total soluble solid (TSS), titratable acidity (TA), technological index (TI), vitamin C, peel and pulp antioxidant capacity, peel and pulp phenolic compounds during experiment. Data analysis was performed using two-year component analysis in completely randomized design for each cultivar in three replications. Mean comparisons were made using Duncan's test and at the corresponding probability level.

In this study, it was found that except for fruit volume values, other fruit physical characteristics were not significantly different in both cultivars. Eureka lemon volume error was less negative (-1.27%) than Lisbon (0.05%), indicating that Eureka lime had fruits with empty space inside or between peel and pulp. Only in Eureka, the highest fruit weight was observed on 27th</sup> October and 17th</sup> November. It seems that Lisbon Lemon passed through three phases of development and has reached the fourth stage. The highest water loss was obtained at 17th</sup> October and 16th</sup> November. Eureka variety with more outer surface, has more water loss. Juice percentage changes relational to harvest time was only significantly in Eureka lime and increased with late harvest. The highest juice percentage (33%) seen in late harvesting time. The total soluble solids in Eureka at four different harvested time and at the end of shelf life was different significantly. The amount of TA decreased during harvesting and storage. According to harvest time, the TSS/TA ratio also increased at both harvesting time and the end of shelf life. Fruit peel thickness only increased in Lisbon lemon during different harvest time. There were no significant changes observed in both cultivars during shelf life. Residue percentage and technology index increased only in Eureka during different harvesting times. Generally, the values of L*</em>, a*</em> and b*</em> at the end of the shelf life were higher than the harvest time. The L*</em> value in Lisbon and the a*</em> value in Eureka did not change significantly over the shelf life. The amount of peel chroma, citrus color index (CCI) and total phenol increased during the shelf life. The amount of vitamin C in both cultivars was high in the 6th</sup> November and was maintained until the end of shelf life. The amount of antioxidant capacity of the peel (50.19 to 75.72%) and pulp (0.49 to 60.92%) of Lisbon and peel (14.47 to 66.81%) of Eureka only showed significant difference at the end of shelf life. The minimum antioxidant capacity of pulp (41.47%) was related to Eureka cultivar which harvested on 5 September which was not significantly different from 17 September and 6 November (52.76 and 47.32%, respectively), while the highest value with 66.81% observed in 6 November. In general, total phenol content of both cultivars decreased during storage. In Eureka lemon, fruits had no significant difference in total phenol content of peel and pulp at different harvesting times and end of shelf life.

</strong> Eureka lemon fruit has an empty space in core or between the peel and the pulp that is important during processing. Lisbon completed its growth stages earlier, but both cultivars had adequate water content (33%) at the time of consumption. According to the technology index, maintains of fruit for 20 days after harvest, improves the quality of the juice. During the shelf life, the decline of peel greening was greater in Lisbon. The fruits harvested at the first harvest (17 October) had a lower CCI value at the end of the shelf life, indicating that the fruits harvested earlier would break green peel color later. The phenol content of the peel was higher than the pulp, but overall the antioxidant capacity of both cultivars was in good nutritional value. Totally based on the physicochemical traits, the fruits of Lisbon and Eureka can harvest from ‎6th</sup> November.

 In today's world, contaminants from synthetic polymers derived from oil derivatives have attracted public attention to the use of degradable materials such as macromolecules. Films and food packaging come from a variety of natural sources including proteins, polysaccharides, lipids, or a combination of these materials (Saremnejad et al. 2009). The characteristics of edible films, including biodegradability, have caused researchers to study the properties of film and various edible packaging as a suitable alternative to plastic packaging (Gonzard and Giulbert 1994). Edible films have appeared as a substitute for synthetic plastic for food applications and have gained substantial attention in recent years due to their benefits over synthetic films. Casings, pouches, bags can be developed from edible films and also be utilized as wraps or covers. At low relative humidity protein films are expected to be good oxygen barriers. Edible films from different protein sources have been formulated. These include casein, gelatin, whey protein, corn zein, soy protein, wheat gluten, peanut protein and mung bean protein (Saglam et al. 2013). Sesame (Sesamum indicum L.) is an important oilseed which is grown in many tropical countries. Sesame meal contains 35 to 40 % protein, is a by-product after oil extraction and it is major protein source used to fed animals in India (Onsaard et al. 2010). Isoelectric precipitation is normally used to prepare sesame protein isolates or concentrates. Sesame protein is very stable to heat and contains large quantities of methionine. So far, there is no work reported on using sesame protein isolate for the formation of edible films for packaging applications.There are several methods to incorporate antimicrobial agents in food, but the most effective of which is the addition of active compounds to packaging materials. Since the surface of the food is a critical region easily exposed to contaminants and packaging material, the slow release of antimicrobial substance to surface of food and, subsequently, diffusion across the food during preservation are predictable. Recently, several nanoparticles such as nanosilver, gold, copper, chitin, and essential oils have been known for their antimicrobial properties. Generally, antimicrobial nanoparticles are classified to organic and inorganic materials, each of which has its particular advantages. For example, inorganic agents are more stable against processing and storage conditions, but organic materials are more compatible, accessible, and inexpensive ( Sahraee et al. 2017). Zinc oxide (ZnO) is one of the most widely accessible metal nanoparticles with low cost, introducing more UV barrier property in polymers in comparison to silver and gold nanoparticles (Llorens et al. 2012).

Sesame meal protein was extracted by two methods of alkaline and saline extractions according to Oonsard et al. (2010) method. In order to increase the protein extraction efficiency, the sesame meal was thoroughly crushed and powdered before extraction, then the sesame powder was mixed with water from 1 to 10 w / v, then in the first method, the pH was achieved to 11 with 2 molar NaOH. In the second method, pH was achieved to 7 with 2 molar NaCl. In both methods, the mixture was stirred continuously with a magnetic stirrer for one hour and then centrifuged at 2822g in 15 minutes and the dissolved phases were separated. The soluble phases were achieved by using 0.1 or 1 M HCl to pH 4.5. The suspension was centrifuged at 2822 g in 15 minutes, then the upper part was discarded and the sediments were weighed and the protein content was measured according to the AOAC 2000 standard. To preparation of films, the sesame meal protein was dissolved in 3 grams in 100 ml distilled water at 25 °C temperature. Glycerol was used in the making of films at 40%, 45%, and 50%; according to a pre-test. Glycerol percentages of less than 40% caused cracking of films, and increased glycerol content by more than 50% caused a high adhesion of films. To prepare nanocomposite films, different amounts of 1%, 3% and 5% of ZnO nanoparticles were added to 100 ml of distilled water and stirred with a magnetic stirrer at 30 ° C for 1 h, followed by ultrasonication for 15 min. Then 3 gr of sesame meal protein and glycerol were added to the solution of ZnO nanoparticles and then stirred for 1 hour. The solution was then heated in a water bath for 30 minutes at 90 °C and then cooled for 20 minutes to remove the air bubbles until it reached 25° C temperature. Then, 100 ml of the film forming solution was poured on Teflon dishes with a diameter of 16 and then dried at 25 °C for 24 h to obtain a uniform thickness. The films were kept in a desiccator with a relative humidity of 50 ± 5% and temperature 23 ± 2 °C (Lee et al.  2014).

In this study, the biodegradable edible films of sesame meal proteins were produced by two different protein extraction methods including alkaline and saline extractions. In these films, glycerol was used as a plasticizer in three concentrations of 40%, 45% and 50% and zinc oxide nanoparticles were used in three concentrations of 1%, 3%, and 5%. According to the results, it was shown that in both samples, the tensile strength and Young's modulus significantly decreased by increasing glycerol, the percentage of length to break and water vapor permeability increased, but the oxygen permeability did not increase by increasing glycerol content. The results showed that Increase of 3% in content nanoparticles, the tensile strength, and Young's modulus increased, but the percentage of elongation to break point and water vapor permeability decreased of the films. With increasing zinc oxide nanoparticles to 5%, Tensile strenght, Young's modulus and oxygen permeability decreased and the percentage of elongation to break and water vapor permeability increased. The results of this research showed that the antimicrobial properties in both samples increased by increasing zinc oxide nanoparticles, and the glycerol level was unaffected. Finally, considering these parameters the tensile strength and the percentage increase in elongation to break, Young's modulus in the protein films were more for the alkaline method than the saline method. But the rate of water vapor and oxygen permeability in the protein films was higher by the saline method.

It was concluded that the films prepared from the sesame meal protein produced by alkaline extraction have stronger inhibitory and mechanical properties than films based on protein extracted by saline solution, which has negative effect salt ions on peptide bonds and positive role alkali is attributed to preventing solubility and better extracting of proteins in these conditions

the production of milk with different flavors causes people, especially children to buy and consume milk more and to get the required amount of dairy daily. Flavored milk is a dairy drink prepared from milk, flavors and a sweetener which is often enriched with vitamins and calcium (Dadgostar 2013). Chocolate milk is the most popular and accepted type of flavored milk. Prevention of physical instability of chocolate milkis an important challenge in the dairy technology (Prakash etal 2010), The main cause of instability of this product is the incorporation process in which the particles of the cocoa milk are joined each other and form a larger particle, and dispersion is divided into two phases. One of the ways to increase sustainability and to prevent sediment and two phases during the maintenance of this product is adding a stablilazer. Hydrocolloids or gums have a wide range of applications in the food industry, such as by increasing the apparent viscosity of the product or by the colloidal interactions of space barrier and electrostatic repulsion which stabilize some food systems (Foroughinia etal 2007). The native Tragacanth gum is an extruded gum of the Astragalus species, which is chemically containing two parts soluble and insoluble in water, which is called tragacanthine and bassorin (tragacanthic acid), respectively (Mohammadifar etal 2006). This gum is a anionic polysaccharide, non-uniform and high molecular weight (Chenlo etal 2010). In the year 1961 by the US Food and Drug Administration (FDA) has been accepted as a healthy food additive (GRAS) (Balaghi 2009). The present research was thus aimed optimizing the formulation of chocolate milkto achieve a product with Desirable physical, chemical and sensory properties.

Optimization of Chocolate milk formulation using response surface methodology and in the form of a central composite design was performed. The desired design was set up using two variables of cocoa powder and Tragacanthin gum. According to primary tests, the range of each of the independent variables was determined and then 5 levels of each independent variable and 13 treatments were presented by Design Expert Software (version 8) (table 3). The samples of Chocolate milk based on the formulations specified in the preparation test plan and were evaluated from the viewpoint of different characteristics. In order to prepare different treatments of Chocolate milk, first 15% of the initial milk volume with 2.5% fat in the hot water bath up to 20°C temperature.Then, the different percentages of cocoa powder, tragacanthin gum according to experiments plan and sugar (7%) and tragacanthin gum According to treatment, was slowly added to the milk and Became uniform by magnetic stirrer (model-Ikarh making Germany). The mixture was heated up to 50 ° C for 20 minutes and finally added to the total volume of milk and was stirred by magnetic stirrer for 20 minutes (Ostadzade etal 2012). Samples were tested after Homogeneisation by Homogenaizer (FG Model 200-S – Hong Kong Country) with a circumference of 1200 per minute, from viewpoint on the physical, chemical and sensory properties of chocolate milk. Also in order to separate the soluble (Tragacanthine) and insoluble (Basorine) parts, one gram of tragacanth powder with one milliliter of ethanol mixed and 200 milliliter of distilled water was added to it. In order to absorb water, the mixture was stirred inside the container for 12 hours by a magnetic stirrer at 4000 rounds per minute. The mixture the was centrifuged at 1700 g for 3 hours (Mohammadifar etal 2006). Thus, the soluble and insoluble sections of tragacanth were separated from each other and the water soluble part was used after drying by spray dryer (Dorsa model- Made in Iran).

The results showed that increase in gum tragacanthin or cocoa powder was accompanied by increase of pH (p˂0.05). and The acidity of the samples decreased with increasing the amount of tragacanthin gum (p≤ 0.05), while adding cocoa powder had no significant effect on the amount of acidity. Addition of any foreign matter to milk can cause change its physical and chemical properties, including pH and acidity. Consequently, the reason for the significant increase in pH with the addition of cocoa powder can be attributed to the higher pH of cocoa (7.49) compared to milk. increase in level of formulation ingredients caused an increase of viscosity of the chocolate milk (p˂0.05). Both independent variables, their interaction with each other and the square cocoa powder had a significant effect (P ≤ 0.05) on the viscosity response. results show an increase of sedimentation amount once the cocoa powder increased. While by increasing the gum tragacanthin concentration, there was a twofold effect in sedimentation amount and in average level of gum, the minimum amount of sediment was observed. So that it increased up to approximately 0.225% of the amount of sediment and its increase from the mentioned value to 0.3% increased sediment content. In justification the results of the present study According to Syrbe etal 1998 theory, the phenomenon of depletion flocculation may occur when the concentration of free hydrocolloid occurs. when the concentration of free hydrocolloid exceeds the required amount and the hydrocolloid is no longer able to absorb water and thus in the form of sediment out. Also, the sensory evaluation of chocolate milk samples showed that most desirability was to be found in samples containing the average level of cocoa powder, but according to panelists, gum tragacanthin did not have a significant effect in general acceptance. The results of particle size distribution analysis of optimum sample size showed that the particle size of chocolate milk without gum and chocolate milk containing gum were 377.38 and 410.88 nm, respectively.

The use of native tragacanthin gum in suitable concentration can be used in addition to stabilization without causing adverse effect on the sensory properties of Chocolate milk. Also, the result of optimal sample particle size showed an increase in the sample particle size by adding this gum. Optimization results also show that, the best sample with the desirable physicochemical and sensory properties was obtained by 5.12 % cocoa powder and 0.10 % of gum tragacanthin in chocolate milkformulation.

 Doogh is a native beverage in Iran and has an import share in beverage industry. Also quality improvement is needs for this native industrialized product. Rheological Behavior in macro and micro scale are the most interesting properties affecting the quality of the food (kiani and et al 2008). The rheological characteristics indicate a possible use as a novel thickener. The dynamic viscosity of the dilute solution shows liquid behavior, and at higher concentrations, viscoelastic and gel behaviors (Razavi and et al 2014). Flow properties of food are determined for a number of purposes, such as quality control, understanding the structure, process engineering application and correlations with sensory evaluation. Also final properties of the product such as stability, texture and appearance are directly depending on food microstructure (kiani and et al 2008). The major problem with this product is phase separation during storage, due to the low pH and aggregation of casein may be seen frequently in   doogh (soltani   and et al 2012). Hydrocolloids have been widely used in textural stabilization of fermented milk products (Koksoy and   Kilic 2004). Gums from seeds are now becoming important additives in the food industry. According to the increasing demand for hydrocolloids, with specific functionality in the recent years, finding new hydrocolloid sources with appropriate properties is an active area of study. Among commercial gums, the hydrocolloids from seeds are still used extremely in food formulations because of their appropriate price, easy availability and proper functionality (Naji-Tabasi and et al 2011). Cress seed gum exists in the envelope alongside the outer layer of the seeds of garden cress (Lepidium sativum L.) plant The seeds consist of 6.5–15% of the mucilage, which contains cellulose (18.3%) and uronic acid containing polysaccharides. Cress seed gum offers a wide variety of food applications because of its yield stress, pseudoplasticity and thixotropy behavior. It is stable in salts (NaCl and CaCl2) and over a wide range of pH’s, with a synergic effect of added sugars (sucrose and lactose) on its flow behavior. It offers applications in emulsifying, emulsion stabilization and foaming properties. It is also stable on heating, cooling and freezing (Razavi and et al 2014).  In this study effect of cress seed mucilage was investigated as a native gum and doogh stabilizer during 28-days storage period at a refrigerated temperature of 5ºC.

In this experiment, Cress seed and yogurt (0.5% fat with acidity 134°D) were bought from herbal medicinal shop and dairy products company (Laleh Sari –Iran) respectively. Then, extracts of dry cress seeds were prepared. Briefly, cress seed was soaked in preheated de-ionized water at a water/seed ratio of 30:1. 0.1 mol /L NaOH solution was used to adjust the pH to 10. The slurry was stirred continuously for about 15 minutes in constant temperature (35˚C). An extractor with a rotating rough plate was employed to cut the gum layer off the seed. This degummed seeds were discarded; finally, the slurry was dried with the 60˚C air forced oven and milled to powders. They were kept in cool and dry condition (Behnia and et al 2013). The gum was then randomly assigned to treatment groups (0, 0.01, 0.1, 0.3 and 0.5%). Preparation of doogh, after dissolution the mucilage in deionized water (Temperature of 80°C for 10 minutes) by adding 0.7% salt, 40 % yogurt was added to the stabilizer mixture and salt then finally product was homogenized with the Ultratorex Homogenizer (11000 rpm for 30 s in 60∘</sup>C) and doogh without stabilizer was considered as a control sample. Then, viscosity, zeta potential, stability, sensory and chemical properties doogh   samples   were measured.

 The statistical analysis of results showed that the doogh samples with 0.5% stabilizer at a low shear rate had higher viscosity in comparison with the control and other samples (P<0.05) (fig 1), The samples showed a pseudo- plastic behavior by increasing the shear rate (Feyzabadi et al. 2014) and This result was in agreement with the finding of (Razavi and et al 2014); that is the cress seed extract shows a newtonian below 0.1%. However, at highers concentrations there is a pronounced shear thin at higher concentrations there is a pronounced shear thinning behavior in steady shear measurement and viscoelastic and weak gel type behaviors in dynamics tests.  Its viscosity depends on many factors such as shear rate, temperature, time, pH, biopolymer concentration.  The addition of cress seed mucilage had a significant (P<0.05) change on the titratable acidity of doogh samples but pH no changed significant these results maybe because of this IR-FT polymer spectrum of cress seed gum polymer showed that the polymer consists of carbohydrates with carboxyl and hydroxyl functional groups (Karazhiyan and et al. 2010) (Table 1). The doogh samples with 0.3 and 0.5% concentration stabilizer had highest stability during storage time (fig 2).  In other study intuitively the link between high viscosity and good physical stability is obvious and this view suffices for many applications (Syrbe and   et   al. 1998) and Findings from the study by Foroughiniaa et al (2007)., Gum tragacantin was the most effective, resulting in full stability of Doogh at a concentration of about 0.3%.  Based on the sensory evaluation results, the consistency score of the samples increased with increasing gum concentration up to 0.3% compared to the control sample, but the difference in concentration of 0.5% with the control was not significant. Apparently that is usually the absolute value of zeta potential in milk products below 25 mV. Due to the noticeable changes in the zeta potential in the samples, electrostatic repulsion plays an essential and inescapable role in stabilization (Azarikia and et al 2009). The   zeta potential was negative   because of anionic nature of the mucilage   that is - 10.78 ±.19 mv. The higher the numerical value of the zeta potential in the formulation containing gum, the lower the repulsive force between the droplets and their less tendency to stick together, leaving the droplets together to stabilize the system (Mirmajidi et al 2016).

The results showed that the addition of mucilage seeds to the concentration of 0.1% on day 28th during storage caused a significant increase in the stability of the doogh samples (62%) and the concentration of 0.3 and 0.5% resulted in complete stability of the samples. The maximum apparent viscosity in samples containing mucilage seed was 0.5% and then 0.3%. Since the highest consistency rating was observed in the sensory evaluation of the samples containing 3%   cress seed mucilage and also its complete stability compared to the control sample, this   concentration is recommended as the most appropriate level.

The functional foods are the main factor in delivering useful components to the body in form of diet which in addition to having nutritional properties also reduce the risk of chronic diseases (Khelgati and zomorrodi 1395). Cake is one of the most popular bakery products which is used among every groups of society because it is ready to use and economical (jad et al. 2017). the purpose of this study was to investigate the cupcake enriched with carrot powder which is a rich source of edible fibers β caroten and minerals.

in this study in order to produce functional oily cake first the dough cake must be produced and for that the ingredients were mixed in two stages. In the first stage solid materials which are flour, sugar, Ammonium bicarbonate, vanilla, and salt, were mixed with a low speed in the mixer for about half a minute, then while mixer was working with a low speed, milk was added so that the dough cake was formed (note that in the samples containing the carrot powder, the powder was added in the first stage along with the other solid materials.) In the second stage the speed of the mixing was increased and the rest of the milk, oil and egg was added to the mixture and was mixed with a medium speed for about 90 seconds. finally, the mixture was put in the oven with the temperature of 150 °C for 21 minutes (Payan 1385). Effect of substituting carrot powder in different levels (0%, 5%, 10%, 15%) with flour on qualitative properties (moisture, color, texture, weight decrease after cooking) along with nutritional characteristics (Acrylamide, total phenol, and DPPH) was evaluated in a form of completely random statistical plan.

Adding carrot powder in different densities considerably increased the moisture of the cake (P<0.05), the maximum values are for the cake with 15 % carrot powder (Table 3). In another study which investigates the addition of apple powder in production of cake (Khelgati and zomorrodi 1395) similar result are reported. On the other hand, the baking weight loss has decreased (P<0.05), and the the minimum result is for the cake which contained 15% (Table 3). Similar studies have been done considering the addition of apple powder in cake (Khelgati and Zomorrodi 1395) and addition of Prickly pear powder in sponge cake (Kim et al. 2012). The amount of L* has been reduced and the amount of a* and b* has been increased (P<0.05), the minimum amount of L* and also the maximum amount of it was related to the sample with 15% powder (Table 4). In another study a reverse result has been observed adding Persian Gum and carrot powder (Nouri et al. 2017) on the features of donut. Considering the structural features, the cake which was produced by adding %5 and %15 carrot powder, did have less stiffness (P<0.05) while the unity of the sample with 15% carrot powder was more. Similar results about the hardening of cakes (Gomez et al. 2008; Lebesi and Tzia 2011) was observed. By adding the carrot powder the phenol compounds and antioxidants activity of the cake samples considerably increased (Fig 1). Similar results in the research of (Sudha et al. 2007) which added dried apple scum by substituting the wheat flour in sponge cake was observed while the acryamil content was reduced. The lease result was in the sample with 15% powder (Fig 2). Similar results in the research of (Sudha et al. 2007) in the antioxidants effects of Bamboo leaves and green tea essence and Rosemary essence was observed. From the total acception point of view the samples with 5 and 10% carrot powder gained the maximum credits. Similar results were gained by sensory evaluators in the study of Hernandez Ortega 2013) by adding the carrot powder scum by substituting flour to the cookie which the maximum results of total acception was for the sample with 5% carrot powder.

 regarding the results, it can be expressed that nowadays due to increasing awareness in the field of food stuffs, the request for the production of functional healthy food stuffs with high nutritional value, low fat, high fiber has increased. Adding fiber to peoples main and daily used food such as bakery products, cake, cookie and donut, can be a pragmatic and suitable way for increase of fiber intake in people’s diet. Carrot is a rich mixture of soluble and insoluble dietary fiber and polyphenols which leads to high antioxidants character of this compound in foodstuffs, therefore it has a lot of healthy effects such as boosting the safety system, increasing the absorption of calcium and reducing the risk of colorectal cancer. Adding carrot powder led to the decrease of acrylamide level while being economic (P<0.05). among the tested samples always the least sensory credit was related to the sample with 15% carrot powder but samples with 5% and 10% carrot powder did have reasonable credits in many tests and there fore are recommended as the best levels for producing the cake from nutritional components and edible fibers.