مجله علوم و صنایع غذایی ایران
سال یازدهم شماره 4 (پیاپی 45، زمستان 1393)

In order to investigate the effect of different levels of temperature، velocity and pretreatment on the drying time of thin layer of Barberries (berberis vulgaris)، an experiment using a factorial experiment conducted carried out based on completely randomized block design with three levels of temperature and three levels of velocity for untreated berries and treated berries with heat shocking and «6% k2co3 + 3% olive oil» emulsion with three replicates. Drying times were affected by temperature and pretreatment at the probability level of 99%. The maximum drying time was recorded 2920 minutes for untreated berries at the temperature and velocity of 60 ºC and 0. 3 m/s respectively and the minimum drying time was recorded 70 minutes for treated berries with k2co3 and olive oil emulsion. In our study multi layer perceptron (mlp) Neural Network with an adjustment learning algorithm of Levenberg-Marquardt with sigmoid logarithm and sigmoid tangent functions were used. The best topology of MLP with LM learning algorithm and Tansig threshold function can predict the moisture content was 4-30-16-1 with correlation coefficient of 0. 9992 and actual error of 0. 00025. Besides the best topology of this neural structure with Logsig threshold function can predict the moisture content was 4-25-5-1 with correlation coefficient of 0. 9991 and actual error of 0. 00032. These results indicate ability of artificial neural network to model and predict drying process.

Three coatings، Carnoba wax، Chitosan and naocomposite، were used to prevent postharvest losses of Golden Delicious apple. The effect of three coatings was compared with uncoated samples on quality and physical properties of apples during storage. These properties were pH، soluble solids (TSS)، color intensity (a، b، L and E coefficients) and density. The variations of quality properties of apples during six months at two conditions of cold storage (2 °C and 95% RH) and environmental storage (20 °C and 45% RH) were evaluated. The results showed that pH، brix and color intensity for three coatings had an ascending trend but density and L had a descending trend in environmental condition. In the environmental condition، the highest color intensity losses were found for the without coating samples and the lowest losses for the wax coating samples. In opposite، color intensity for the wax coating samples had lowest losses. There was no more change in brix trend for nanocomposite coating.

Grape seed oil is the vegetable oil which has essential fatty acids such as linoleic acid and antioxidant compounds such as tocopherols and polyphenols. Production and consumption of this oil has gained attention in recent years. Using this oil in diet due to its nutritional properties can have a significant role in health. Therefore، in this research، the effect of frying on some qualitative properties of grape seed oil has been investigated. For this purpose، grape seed oil was heated at 180 ºC for 0 (control)، 30، 60 and 90 minutes. Then chemical analysis such as acidic value، peroxide، anizidin value، the amount of tocopherol، polyphenols، carotenoides، chlorophyll and oxidation stability were carried out on the oil. The results showed that the acidic value was increased significantly by heating. The peroxide value first was increased and then was decreased significantly by heating. The anizidin value increased significantly as the peroxide value was decreased. The amount of tocopherols، polyphenols، carotenoids and chlorophyll were decreased significantly during the heating process. The results of oxidation stability showed that the grape seed oil has not high oxidation stability against heating.

Growth of Pathogenic microorganisms is one of the major obstacles in the food industry. An innovative method has been introduced for impregnating porcelain pots with antimicrobial silver nanoparticles. Silver nanoparticles have been produced by reducing silver nitrate with hydrazine. Particles have then been impregnated in porcelain pottery using a pervaporation technique. Samples of the pots have been analysed by SEM، EDX، XRD and AFM. Antibacterial properties of the pottery have been confirmed by exposing them in broths containing Escherichia coli and Staphylococcus aureus while the destructive effects have more profoundly been detected on gram negative Escherichia coli as compared to gram positive Staphylococcus aureus. The finding is attributed to the thicker Staphylococcus aureus membrane as compared to thinner membrane of Escherichia coli. It is also found out that a higher silver particle content of the samples results in a stronger antibacterial property.

In this study the effect of microwave power on drying behavior، effective moisture diffusion، the best mathematical model of drying، activation energy values and energy consumption of the herb thyme was investigated. Results of regression analysis of mathematical models in MATLAB software points that the Midili model has the best described to the data. Effective diffusion coefficient of herb thyme was found to be between 15. 416 and 213. 802m2/s. Also the activation energy was determined to be 84. 86 W/g for constant drying rate and 100 W/g for effective moisture diffusion. In addition، the minimum and maximum value of specific energy consumption drying of herb thyme was 6. 994 to 19. 607 kW/kg، respectively.

Milk fat is one of the most important components used in ice cream mix formulation، which affects textural and rheological properties of the final product. According to the definitions released by FDA، ice cream products are categorized in several groups (non-fat، low-fat، light، reduced fat and full fat). In this research reduced fat، light، low fat and full fat vanilla ice cream samples were produced with 2، 5، 7. 5 and 10% milk fat respectively، and the rheological properties of the ice cream mix and some physical properties of the ice cream product were evaluated. The results showed that the freezing point and the draw temperatures of the samples were increased with decreasing of fat content. All the ice cream mix samples showed pseudoplastic behaviour and their apparent viscosity tended to decrease with increasing of shear rate. Increasing of fat content made the ice cream mixes to have lower flow behaviour index and thus increased the pseudoplasticity in the mix. The consistency coefficient and the apparent viscosity of the samples also increased significantly with increasing of fat in the samples.

Apple fruit as horticultural products is considered very valuable in terms of food production and employment and exchange technology in Iran. Due to increasing industrial production methods and significant public demand of dried apple layer as an apple product، qualitative separation methods for long time lasting of this product becomes more important. In microscopic scale of fast chilling method، internal surface of dried apple layers consist of Crystal-like beads which are different in size and shape. Finally، arrangements make unique structure before and after of reduction lasting quality. In this research، a technique was presented to fast sorting during constant time process using machine vision technology. At first، the encryption operation for identification of Defined parameters using two methods of Wavelet decomposition and Wavelet packets was done and finally pictures sorting for identification of dried desirable layers from inferior layers using energy values in images after encryption operation were done. Results showed that the Wavelet packets method was more capable in images encryption than the other method. Energy interval detection threshold in images was found quite effective which can identify images of 2600×2600 pixels desirable layers in 0. 86 second.

Investigation of chemical، sensory and microbial characteristics of flours in Khuzestan Bread consumption in most countries is too high، and it supplies a large part of people''s daily calorie and protein requirements. Since the production of suitable bread requires the use of flour with specific features. The flour produced in Khuzestan province to determine quality characteristics were evaluated for their use. Chemical، microbiological and sensory properties of Flours from 13 factories in cities Andimeshk، Ahvaz، Ize، Behbehan، Khorramshahr، Dezful، Shosh، Shoshtar، Mahshahr and Masjed Soleiman، were determined using standard methods. The results of chemical characteristics show significant differences (p ≤ 0. 05) of the flour. So that Protein، ash and moisture content and pH value Flours is the limit. Characteristics of microbial contamination of wheat flours showed that the mean total count، yeast and mold them into compliance with national standards in Iran. The evaluation shows that in different types of flour color، smell and taste are normal and there are no live pests and foreign impurities. Overall، this study shows that although flours have the minimum protein and wet gluten for bread production. However، according to low Zeleny index، they cannot produced bread with good quality، therefore it has better adding additives or mixing them with flours from other areas.

In this reasearch، optimal condition on oil and arachidonic acid production by mortierella alpina CBS 754. 68 was investigated using response surface methodology. Tow factors which influencing arachidonic acid and oil production; including carbon source (glucose) in five levels (45. 8، 50، 60، 70 and 74. 14 gl) and nitrogen source (soybean meal) in five levels (7. 92، 10، 15، 20 and 22. 07 gl) were studied. Arachidonic acid and oil yield varied msignificantly in response to changes in concentration of soybean meal and glucose. The model predicted that، maximum production of AA (that is، up to %56. 40) and oil (that is، up to %50. 13) could be achieved using the medium containing (glucose 50. 35 and soybean 18. 30 gl) and (glucose 70 and soybean 10 gl)، respectively. In the next stage change the medium composition and biomass during fermentation was investigated in two medium optimized. The results showed that oil and arachidonic acid production significant increase with fungi and storage oil stopped respectively. Phenolic compounds are directly related with cell growth rate and the amount of fungi oil. Keywords Keyword: Mortierella alpine; fermentation; Arachidonic acid; Oil; Response surface methodology

In recent years، following the mechanization of life، people tend to have products with higher quality and longer shelf life. Following this demand، studies have been introduced different technologies to the food industry; the part baked and frozen bread has been more attention. Although freezing، frozen storage and thawing have detrimental effect on bread properties. Use a variety breads improvement such as emulsifiers، oxidants and hydrocolloids can be used to reduce this impact without any negative effect. The aim of this study produce semi volume Barbari bread as part baked and frozen storage، in order to increase their shelf life and adding guar gum and lipase to formulation for improve quality، rheological and sensory characteristics in cycle freezing، storage and thawing. Bread prepared as part baked، freezing in -18ċ and storage for 15 day، after this time samples were thawing and full baked. Then volume، porosity، texture، index image and sensory properties were measured. For Data Analysis used Statistica software and Duncan test، for mean comparisons. The result showed guar gum in 0. 4 concentrations can be improvement volume، porosity، texture، index image and sensory properties، lipase at 0. 05 level influenced on volume، porosity، texture in sensory properties and index image.

A lot of reasons are effective on growth of microorganisms during the storage of sugar beet in the silos. In this study، effect of the size of sugar beet (in 4 levels) and height of storage them (in 4 levels) in silos، in duration of 18 days، on growth changes of microorganism are investigated. In our study we observed that maximum activity microorganism growth (bacteria، mould، yeast and total count) in smallest sugar beets and minimum activity in biggest sugar beets. Also، maximum activity of microorganism growth belongs to the sugar beets that stored on 3 meter height and minimum activity belongs to stored on 5 meter height.

Sugar beet press water is one of the main wastewater in the sugar industry، which presently returned to the diffuser with no further treatment. Some form of treatment، such as pretreatment with membrane may however، improved the output efficiency of sugar plants. In this study، nanofiltration membrane (AFC80) were used to investigate the permeate flux، fouling percent and rejection percent of most important molassogenic ions (sodium and potassium) and sucrose. Sugar beet press water was provided by Abkoh sugar beet factory. The effect of operating parameters such as temperature (at levels of 25،40and 55ºC)، trans membrane pressure (at levels of 10،15and 20 bar) on nanofiltration performance (permeate flux، fouling and rejection) were investigated. The results show that maximum permeate flux is obtained at 55 ºC and 20 bar، while the average value is 49. 27 kgm-2h-1. The minimum permeate flux is obtained at 25 ºC and 10 bar، and the average value in this conditions is 14. 63 kgm-2h-1. Maximum and minimum fouling are reached at 55 ºC and 20 bar and 25 ºC and 15 bar، respectively. Furthermore maximum rejection of sodium and potassium (84. 3% and 72. 5% respectively) is obtained at 25 ºC and 20 bar، and minimum of rejection of sodium and potassium (74. 3% and 69. 05% respectively) is obtained on 55 ºC and 10 bar. For all operating conditions، sucrose rejection was exceeded 95%. Variation in operating conditions had no significant effect on sucrose rejection.

In this research modified corn starch (pregelatinisation) was used at levels of 3،5،7،10% levels to substitute wheat flour and production of barbary bread. Chemical analysis (moisture،ahe،insoluble ash، protien، fat، fibre، pH، particle size، moisture and dry gluten zeleny test، falling number was determined on corn modified starch، blank and treated flour. The rheological properties of dough were also evaluated by farino،extenso amylographs. Staling analysis was done in days of 1،3and 5 by 6 trained panel. Moisture، ash، acid insoluble ash، moisture and dry gluten، protein،fat، zeleny number، pH was descreased by corn modified starch(pregelatinisation). falling number increased by corn modified starch (pregelatinisation). But fibre content was not changed. The results of rheological tests showed،That water absorption and softening degree was increased but stability،development time and quality number was reduced in farinogram and resistence to extention، extensibility and area under curves was improved in extensogram. The results of amylograph test showed that gelatinization tempretur was reduced،and peak viscosity of blank speciment was not significantly different with pregelatinization starch speciment (5%). The results of sensory test showed that treated breads quality were acceptable and were retareded staling.

In this research drying kinetics، moisture diffusivity، determination of most appropriate mathematical modeling and activation energy of white mulberry were studied under microwave oven. For determination of most appropriate model، the highest value of R2 and the lowest values of c2and RMSE were used. For mathematical modeling، nine empirical models were fitted on experimental data and the best model was selected. The result of regression analysis showed that Midilli model has the best fitting with data. Moreover، the highest and lowest values of moisture diffusivity were obtained as 5. 3×10-6 and 1. 42×10-6 at power of 500 W and 200 W، respectively. Also the values of activation energy and moisture diffusivity in the drying of white mulberry were obtained as 10. 83 and 1E-5 respectively، based on an exponential relationship. Finally، the value of specific energy consumption for drying of white mulberry was found between 0. 7 to 2. 58.

Gliadin is one of the gluten constituents، with unique functional properties. In this study، gliadin was extracted from commercial gluten by solubilization in ethanol then functional properties of gliadin including water absorption، water holding capacity، foaming capacity and stability، emulsifying capacity and stability at various pH values of 3، 6 and 9 and two protein concentrations (1 and 2%) were investigated. By determination of the gliadin functional properties، as a plant protein، it is possible to extent its food and non food applications. The lowest water holding capacity، water absorption، emulsifying and foaming capacity of gliadin were obtained at pH 6 and the highest values were obtained at pH 3. pH changes had no significant effect on electrophoretic pattern of the gliadin. It was concluded that gliadin is suitable to use in acidic foods.

The aim of this study was production of chitosan from chitin of local shrimp shell and comparison its qualitative properties with commercial chitosan which has been produced by crab shell. In the first step، the shells of Persian Gulf shrimps were prepared and chitin was produced from them by demineralization، deproteinization and discoloration treatments. Then، chitosan was obtained by deacetylation of the chitin. Film samples were prepared by the chitosan and their thickness and water vapor permeability (WVP) were determined and compared with the commercial chitosan. Also، chemical composition (moisture، ash and protein)، degree of deacetylation، water binding capacity، fat binding capacity and color of the produced chitosan samples were determined and compared with the commercial chitosan. The results showed that the chitosan production yield was acceptable (%19. 43). In view of the chemical properties، the produced chitosan had lower protein and ash impurites، lower degree of deacetylation، higher water binding capacity and higher fat binding capacity than the commercial chitosan. The prepared film samples of the produced chitosan showed lower water vapor permeability (WVP) than the commercial ones. Also، the produced chitosan had more color lightness than the commercial chitosan. Overall، it can be concluded that it is possible to produce suitable quality chitosan by shells and waste of local shrimp، therefore، the shrimp production and shrimp packaging factories of Iran can be proposed to produce chitosan.

The shrimps and fishes provide good food sources of protein and contain good fat and calories and are as a healthy food. This study analyzed biochemical composition of the Persian Gulf selected processed shrimps such as pink shrimp (peanaeus sewisulcatus)، white (Metapenaeus affinis) and glassy shrimp from families pana lirus homareus and Two fish species of tuna for evaluation of nutritional values in before and after processing for control of the nutrients process during process and after it. Protein، fat، ash and moisture contents of the shrimps and fishes were analyzed using AOAC methods. The carbohydrate percent of white shrimp was (41/4) g that in comparison with others was high. Total energy of the glassy shrimp (393/5324) was higher than others. The comparison of protein، fat and ash contents of samples showed that the glassy shrimp contain high fat، protein and ash contents، while ash content in pink shrimp was highest value. Results showed fat contents of all samples increased after processing while ash and protein contents decreased for Katsuwonus. Moisture content decreased for Euthynus after processing and during in storage time while it was not clear in Katsuwonus. pHlevel was little acidic in fresh fish in comparison to canned fish. It is concluded that the Pana lirus homareus shrimp because of high protein، fat and energetic values، was suitable for processing in the future and we can proposed it for next processing.

Walnut green husk is waste of walnut that can be valuable source of natural compounds with antioxidant properties. In this study, the effect of regions (Shahrood, Bandar Gaz and Hzargarib), solvent (ethanol 96%, Water and ethanol - water (1:1 v/v)) and extraction time (6 to 24 hours) on the yield of extracted phenolic compounds from walnut green husk has been analyzed. Immersion method at room temperature in a factorial experiment with three replications in a completely randomized design has been used. Then, bioactive properties of walnut green husk extract in a completely randomized design have been compared. The total phenol content of the extract was determined by the method of Folin- ciocalteau. Antioxidant activity of the extract by the reducing power of Iron III and DPPH free radical scavenging ability was evaluated. The results of this study showed that, the solvent polarity, time extraction and plant habitat are effective on amount of extracted phenolic compounds; and also antioxidant activity of the extract depends on the concentration of phenolic compounds. The highest phenolic compounds with 49.66 mg/g (based on Galic acid) were achieved from Hezar jerib walnut green husks with water - ethanol solvent (1:1 v/v) for 24 hours. Also, the most antioxidant properties of the extracts were shown in this extract.