نشریه فرآوری و نگهداری مواد غذایی
سال دهم شماره 1 (پیاپی 23، بهار و تابستان 1397)

 

CoQ10 is a lipophylic natural antioxidant with fundamental role in mitochondria bioenergetics. The positive effect of CoQ10 in therapy of many diseases is due to its antioxidant and bioenergetics properties. Reduction of endogenous synthesis of CoQ10 by the ageing, insufficient amount in the food and several health benefits of CoQ10 have led to food fortification. The objective of this study was to microencapsulate CoQ10 by complex coacervation method and determinate of optimum mixture component (β-lactoglobulin (β-lg), Arabic Gum (AG), Oil containing CoQ10 and water) to achieve maximum value of microencapsulation efficiency (ME) and payload. Due to temperature sensitive characteristic of CoQ10, Gelatin was replaced with β-lg and combination of β-lg and AG were used to microencapsulation of Oil containing CoQ10.

At first CoQ10 powder and olive oil were poured in opaque tube and stirred in incubator shaker for 24h. Then solutions of β-lg and GA were prepared at 1-4% (w/w), by dispersing the required amount of them in deionized water and microcapsules were formed by adding oil phase containing CoQ10 to the β-lg solution and preparation of emulsion, adding the GA solution and adjusting pH to 4. After separation of microcapsules freeze dryer was used to dehydration of them, and Morphology of CoQ10 microcapsules was examined using a Scanning Electron Microscope (SEM) and an optical microscope. The particle size and the particle size distribution of moist microcapsules were determined using a particle size analyzer. In the next stage it was used from n-hexane to extracting oil and extracted oil was dissolved in 1,4-dioxane and analyzed by a high performance liquid chromatography (HPLC) system, and microencapsulation efficiency was calculated for microcapsules before and after freeze drying. At the end the effect of oven drying and defrost on microencapsulation efficiency was studied for 5 formulations.

ME values before drying for all formulations except one sample (containing: 4%β-lg, 4%AG, 5%Oil and 87% water) were in the range of 94.05-99.01%. Variation in ME and payload values after freeze drying was in the range of 34.91-92.45 and 24.78-83.75%, respectively and sample containing 2.5% (w/w) β-lg and 2.5% (w/w) AG and 5 % (w/w) oil obtained the highest ME value, an homogeneous particle size distribution and had a smooth and free of pores surface.

Based on the results, formulation containing 2.5% (w/w) β-lg and AG and 5 % (w/w) oil can be successfully used to microencapsulation of CoQ10

Sponge cake as a snack food has Great popularity among individuals. It seems by fortifying its formulation as a popular snack food, can prepare a functional and nutritive formulation. On the other hand, with increase in sensitivity to gluten and celiac disease, demanding for gluten free or gluten reduced has increased. Due to the importance of proteins forming the viscoelastic gluten network in creating of desirable rheological characteristics of bakery product, the necessity use of proteins with similar characteristics to replace the gluten protein is evident. The aim of this study was to prepare a functional and nutritive product by using rice flour and wheat germ flour as substitute of wheat flour in sponge cake formulation. The cake batter samples were prepared based on 100 percent rice flour, also, wheat germ flour were used at levels of 0, 5, 10, 15, and 20 percent in batter formulations. Also, one sample containing wheat flour was prepared as control. Due to important role of wheat protein in forming of texture of dough and cake, Impact of replacing wheat flour with rice flour and wheat germ flour on dough rheological properties of resulting cake was investigated. After defatted wheat germ flour preparation, cake samples were prepared according to specified formulations. To study the rheological behavior, stable rheological tests (flow behavior) and sweep tests (strain sweep and frequency sweep) on obtained dough were applied by using rheometer equipped with two parallel plates. Results of flow behavior test indicated that all batter samples exhibited thixotropic shear thinning behavior under steady shear tests, which fitted by Power law model and the factors related to this model were specified in the samples. Also, it was observed that batters exhibited weak- gel like properties, by using dynamic oscillatory shear tests and had significant effects on acquired parameters from frequency sweep test, such as storage modulus, loss modulus and tan delta (P<0.05). Sample containing rice flour exhibited weak rheological characteristics compared with control. However, with increasing wheat germ flour levels (from 10 percent to 20 percent), viscosity and consistency coefficient increased, and the combination of rice flour and 10% wheat germ flour was closest to the control. It can be concluded, this is possible to prepare a functional product with desirable rheological characteristics by applying appropriate levels of rice flour and wheat germ flour as wheat flour substitutes in sponge cake formulation

Biopolymer-based films such as chitosan have been studied widely due to their biodegradability and biocompatibility. Chitosan has a great potential for a wide range of food applications but its’ hydrophilic character, and consequently its poor mechanical properties in the moist condition, limits its application (1, 2). Composite films have received much attention, because of their extraordinary possibility to improve the properties of films. One of the promising ways to modify biopolymer properties in terms of physicomechanical properties, inherent water sensitivity, and their relatively lower stiffness and strength, is to make hybrid films using biopolymers and nano-sized fillers known as nanocomposite films. In this research, the effect of bentonite nanoclay/chitosan ratio on the water vapor permeability (WVP), mechanical properties, and surface microstructure of the chitosan nanocomposite films was evaluated.

In this research, chitosan biopolymer aqueous solution with two concentration (2, and 3% w/v) and bentonite nanoclay solutions with two clay compositions (1 and 3% based on chitosan) were prepared, separately. The chitosan solution was then slowly added to the clay suspension at 55oC. The nanocomposite films were prepared using the solvent-casting method. The films based on 2 and 3% chitosan were considered as unfilled control samples. The water vapour permeability (WVP), tensile strength (TS), elongation at break (E), and microstructures of the films were investigated.

The results show that at identical concentrations of chitosan the amount of bentonite nanoclay affect the WVP and tensile strength (TS) of chitosan films, significantly (p<0.01). By adding 1% nanoclay bentonite to polymer matrix, the value of TS strength of nanocomposite film increased to approximately 0.66 (2% chitosan) and 0.35 MPa (3% chitosan). Moreover, the elongation value decreased to 8.8% and 6.47% in the nanocomposite films based on 2 and 3% chitosan, respectively. Further increase in clay content to 3 wt%, the WVP, elongation and TS of nanocomposites film decreased for chitosan 2 wt%. According to the SEM micrograph, non-homogeneous structure was found for 3% clay-chitosan nanocomposite in comparision to 1% nanoclay loaded chitosan nanocomposite in full agreement to the decrease in TS value observed. With increase the percentage of nanoclay bentonite to 3%, the pore spaces of film increased and consequently the TS exhibited decreased

According to the findings of this research, interactions between nanoclay and chitosan in nanoclay-chitosan nanocomposite have led to the formation of a new material with enhanced mechanical, morphological, and WVP properties than the pure chitosan. Finally, in 1% nanoclay concentration, the water vapor permeability, elongation, tensile strength, and also consistency of the microstructure films were significantly modified in compare of pure chitosan

Cream cheese is a product made from pasteurized milk and cream and has a smooth, slightly laminar texture. Due to the high nutritional value of dairy products, their production and use are increasing. But due to the high fat content of some dairy products such as cream cheese, their consumption is harmful in some cases and threatens consumer health. Therefore, demand for low-fat and low-calorie dairy products is increasing.cheese Fat is also effective in improving the appearance and texture of the cheese. Usually low-fat cheeses, had undesirable texture and flavor.therefore in this study,the effect of microbial transglutaminase and gelatin was investigated on the texture properties such as hardness, cohesiveness, resistance and chewiness , viscosity and sensory properties of low-fat cream cheese.

In this study, gelatin and transglutaminase were used in the formulation of low-fat cream cheese. Effect of gelatin levels three (0.2, 0.4 and 0.6 %) and microbial transglutaminase levels three (1, 3 and 5%) by measuring the texture rheological and sensory properties using response surface methodology and design expert software 6.0.2 version were performed. The experiment was conducted based on Box- Behnken design with three factor and three levels comprising a total of 13 tests. Sensory evaluation was done with Hedonic method. Rheological properties of texture analysis were done using the Texture Analyzer. All samples produced in the same condition and were stored at 6-4 ° C and tested on the fifth day after production.

Cream cheese properties were assessed by diagrams and models for each response were quadratic polynomial. Since the coefficient of determination (R2) for models obtained for all rheology and sensory characteristics were more than 0.8, lack of fit for all above character were not significant at the 5% level, the model were approved for fitting information. Finally, based on the rheological characteristics of the cream cheese determined the optimal production production.

Response surface designs optimization showed that desired rheological properties for cream cheese, transglutaminase concentration of 3.01%, gelatin concentration of 0.38%, were identified as optimal, Leading to a low-fat product with rheological and texture properties would be desirable similar to the full-fat control sample, and also the sensory properties evaluation revealed that the optimized sample was considerably more appreciated by consumers counterpart. Keywords: Cream cheese, Rheological properties, Low-fat, Transglutaminase, Gelatin

Pumpkin is a good source of carotene, water-soluble vitamins and amino acids. Pumpkin can be processed into flour which has a longer shelf-life. Pumpkin flour is used because of its highly-desirable flavour, sweetness and deep yellow orange –red colour. In this study, kinetic modeling of pumpkin drying in an infrared-hot air dryer was investigated. Malting is one of the biotechnological processes that includes steeping, germination and killing of cereal in controlled environment in which hydrolytic enzymes are synthesized and cell wall, protein and starch of endosperm are largely digested. Cakes by appropriate organoleptic characteristics are considered the most commonly used flour products all over the world. According to the role of dietary fiber on health and prevent some types of cancer and diabetes, fans of high-fiber foods is increasing.

In this study pumpkin and malt powder at four levels of 0, 10, 20 and 30 % as substitute of wheat flour was used in the cake formulation. The effect of pumpkin and malt powder replacement with wheat flour on physico chemical and sensory properties of sponge cake including pH, fat, protein, moisture, ash, β-carotene, mineral, carbohydrate and texture were evaluated. Textural properties were evaluated by texture analyser (TA XT PLUS model, Stable Micro systems, U k).

The results showed that treatments didn’t have significant difference effect on pH. With increasing of pumpkin and malt powder on sponge cake formulation no significant difference was observed between the fat and protein contents of cakes and sample fat and protein contents were in the range of 24.34-27.23 and 8.40-8.75 %. But moisture, ash and carbohydrate contents results show significant difference (P<0.05). It was observed with addition pumpkin and malt powder on the flour the texture of sponge cake was softer. With increasing in pumpkin and malt powder significant difference was observed between the β carotene contents of cakes and β-carotene content was between 0.40-1.98 mg/100 gr. With increasing of pumpkin and malt powder on sponge cake formulation significant difference was observed between the calcium and iron contents of cakes and sample calcium and iron contents were in the range of 500-700 mg/100 gr and 40.75-59.70 mg/100 gr With increasing of pumpkin and malt powder significant difference was observed between the textural properties of cakes.

Sensory evaluation of treatments showed that manufacturing sponge cake with 10% of pumpkin and malt powder is the best cake formulation

Soy has long been a great source of high quality vegetable proteins rich in lysine amino acid, which the most cereals are deficient, is known. The nutritional value of soybean increases by germination, because as the result of sprouting stage, plant enzymes are activated and in consequence of enzyme activation its anti nutritional factors are diminished and digestibility of proteins and carbohydrates is increased. The aim of this study is increasing the nutritional value of bread while maintaining or even improving its quality using germinated soy flour.

In this study, effect of adding germinated and non-germinated soy flour at concentration of % 10 (based on flour weight) on dough properties and barbari bread quality was studied. After bread making; moisture content, symmetry index, dough properties such as: water absorption, dough development time, stability time, degree of softening and quality number were measured by a Farinograph.

The results of this study showed that adding germinated and non germinated soybean flour to bread formulation have not adverse effect on bread quality properties and even in some of its characteristics were improved. Moisture content analysis results showed that bread crumb including germinated soy flour had the most moisture content and it was significant different from bread including non germinated soy flour and control bread (P>0.05). According to symmetry index there was no significant difference between control bread and bread including non germinated soy flour (P>0.05), and bread sample having non-germinated soy had the most symmetry index. Moreover, based on Farinograph results, both bread samples containing soy flour were better than control sample except for stability time factor which significant difference was not seen between control bread and germinated soy bread. By addition of germinated and non germinated soy flour to bread formulation, the microstructure of bread samples improved in comparison with control bread. According to sensory evaluation, there was no significant difference among samples except for color value. The bread sample containing germinated was significantly lower than the control bread and bread including germinated soy flour based on color value.

Totally , according to quality properties such as moisture content of dough and bread and symmetry index, bread including germinated soy was superior than non-germinated soy but based on dough stability, bread color and microstructure, the bread containing non-germinated was enhanced. According to these findings, adding soy flour to the bread formulation, specially for non-germinated soy flour can be used as an inexpensive way to improve the nutritional quality of the community.

Oxidation is main causes of oils and fats rancidity. Oil oxidation changes the organoleptic properties of food and also reduces nutrition value and shelf life of oils. Synthetic antioxidant is added to oils and fats to preventing off-flavour that occur by oxidation. Due to the adverse effects of synthetic antioxidants such as TBHQ ،BHT ،BHA and GA on human body including mutagenic and carcinogenic effects, production of natural antioxidant as alternative for synthetic antioxidants it is necessary. The aim of this study was to evaluate the effects of extraction techniques on phenolic compounds and antioxidant activity of white mulberry leaves extract as natural antioxidant.

The white mulberry leaves after drying were milled and extracts were extracted using maceration (ethanol solvent – water, 50:50), ultrasound assisted and supercritical fluid extraction methods. Total phenolic compounds (TPC) and tocopherol (TC) were measured using Folin–Ciocalteu method and colorimetric assay and antioxidant activity of extract in 500, 1000, 1500 and 2000 ppm concentrations were measured using 1, 1-Diphenyl-2-picryl-hydrazyl)DPPH (radical scavenging, β-caroten/linoleic bleaching assays. Antioxidant activity of extracts was compared with synthetic antioxidant (TBHQ).

The TPC and TC in ultrasonic extract were higher than other extracts due to extraction conditions. The DPPH radical scavenging activity of extracts at different concentrations showed that free radical scavenging of the all samples increased with increasing of concentration of extracts and statistically significant difference was between different concentrations. Free radical scavenging value was varied from 40. 98% to 77. 46%. In β-Caroten/linoleic acid method was observed antioxidant activity of all extracts examined increased with increasing of concentration of extracts. In all concentrations examined, samples with ultrasound-assist extraction had the highest antioxidant activity and extracts with maceration extraction method showed the lowest antioxidant activity. By increasing in extract concentration from 100 to 2000 ppm, antioxidant activity increased and 2000 ppm of extract had not statistically significant difference with TBHQ.

Generally, the results of the present study indicated that the ultrasound-assist extraction was more effective in antioxidant activity of white mulberry leaf extracts in the DPPH free radical assay and β-carotene/linoleic bleachin. The high antioxidant activity of the extracts appeared to be attributed to its high tocopherol and phenolics content. Therefore, white mulberry leaf extract can be used as a natural antioxidant to replace the synthetic antioxidants in food industry

The problems of drying in the paddy factory is lack of unuiformity drying in the paddy rice that creates stress temperature and moisture and thus will cause fractures in the later stages. The purpose of this research was to develop a performance history rice healthy white paddy drying in the shortest time.

The problems of drying in the paddy factory is lack of unuiformity drying in the paddy rice that creates stress temperature and moisture and thus will cause fractures in the later stages. The purpose of this research was to develop a performance history rice healthy white paddy drying in the shortest time.

The problems of drying in the paddy factory is lack of unuiformity drying in the paddy rice that creates stress temperature and moisture and thus will cause fractures in the later stages. The purpose of this research was to develop a performance history rice healthy white paddy drying in the shortest time.

In this study, to reduce losses and increase the drying rate of a rotary dryer machine utilizing the innovative laboratory. Response surface methods and central composite design software for modeling and design expert was used to obtain the optimum condition. Independent variables include temperature (40 to 80 °C), rotating cylinder rotation speed (2 to 10 rpm) and the full cylinder (25 to 66%) was rotary dryer. The quality parameters percentage of breakage, percentage of crack and drying time were used as response parameters to develop predictive models and optimize the drying process.

The results showed significant effects of the variables of interest on the amount of waste and the temperature has the greatest impact on the amount of waste and drying times, also decreased with increasing rotation speed drying time. The results of the optimization process with a minimum amount of waste (percentage of breakage and percentage of crack) and drying time in the inlet air temperature 56.53 °C, the speed of rotation of the cylinder 10 rpm and the full cylinder 54.20% was found.

The condition of drying process have important rule in final quality properties and waste of paddy rice. The study revealed that RSM could be used to develop adequate prediction models for describing quality changes in paddy rice during drying. The changes in the quality parameters were adequately described by quadratic model. Successful optimization for the paddy rice drying process can also be made using desirability functions in RSM