JOURNAL OF FOOD RESEARCH (UNIVERSITY OF TABRIZ)
Year:2016 | Volume:26 | Issue:1|Papers Count:17

Pasta is produced from semolina flour usually and it possess the good quality and market friendly. The functional foods, in addition to nutritional value, have at least one specific property and proven health promotion and prevention some diseases like, cardiovascular disease, diabetes, and cancer of the gastrointestinal tract. Wheat bran is a cheap food, nutritious and full of fiber. Nowadays, the role of dietary fiber and its effects on human health and the prevention of chronic diseases such as obesity, cardiovascular disease, diabetes, and cancers of the gastrointestinal tract are important. The purpose of this research was producing of wheat pasta enriched with good quality and high nutritional value. In this study, the effect of adding wheat bran on Picolli pasta chemical properties and quality, at levels 10%, 20%, and 30 compared with the control. Effect of wheat bran on the chemical properties and quality of pasta (moisture, ash, color, cooking time, cooking loss number, weight after cooking and sensory evaluation) was evaluated. Results showed that with the increase in wheat bran, moisture, ash, time, and weight increased compared to control after cooking, but the cooking loss number was reduced and color was darker. The results showed superiority of chemical properties, and sensory quality of pasta up to 20% wheat bran compared to the other levels.

Degumming is the first step of oil refining. The aim of this study is using Ultrasonic waves in degumming process with presence of water in order to reduce the time and temperature of process in regard to conventional Water Degumming. Soybean and Sunflower oils were added 3% W-W water and were placed in Ultrasonic Bath (150w, 20 KHz) treatments times were 10,20,30 min in temperatures of 30oC and 60oC . Conventional Water Degumming of Oils (T 60oC, t 30 min) were done in order to compare with Ultrasonic Water Degumming. Primary Phosphorus content of soybean and sunflower oils were respectively 508 ppm and 329 ppm that reduce to 24.5 ppm and 31.8 ppm after Conventional Water Degumming and reduce to least Phosphorus content of 9.7 ppm and10.8 ppm in Ultrasonic Water Degumming. A composition of FAs was not change after degumming by Ultrasonic waves and there were not also a considerable change in peroxide values. Usage of Ultrasonic Waves in Degumming process was so efficient. Ultrasonic Waves can reduce phospholipids content of oils in lower Times and Temperatures in regard to conventional Degumming and do this without any destructive influence on FA composition.

In this study, the effect of zedo, commercial stabilizer CHO, arabic and xanthan gum on the stability and qualitative properties doogh were investigated using response surface method (RSM). The amount of zedo and commercial stabilizer CHO were in the range of 0-0.4%, Arabic gum and xanthan gum were in the range of 0-1.8 and 0-0.2% respectively and storage time was 7-59 days. The statistical analysis of results showed that serum separation decreased with increasing the levels of gums and it increased during storage (P<0.05). Also Apparent viscosity was significantly increased with increasing the levels gums (P<0.05). According to the results obtained from color analysis, L* value increased during storage time but it decreased under the interaction of xanthan gum and commercial stabilizer CHO. At lower levels of Xanthan gum and Arabic gum a* value decrease and at higher levels of a* value increased. Both zedo gum and Arabic gum resulted in b* value improvement. According to the sensory evaluation, with increasing concentration xanthan gum and commercial stabilizer CHO the score of flavor and with increasing concentration any of four types of stabilizers the score of consistency decreased. The amounts of xanthan gum 0.17%, zedo gum 0.16%, commercial stabilizer CHO 0.36%, Arabic gum 0.97% and 56 days storage were obtained as optimum conditions.

Nowadays, trend of producing and consuming functional foods has increased dramatically due to the adverse consequences of dietary imbalances and impaired in human societies. Wheat germ is unique source of highly concentrated nutrients that makes it ideally functional additive for fortification of food products to improve human health and prevent or reduce the risk of disease. The aim of this study was to investigate effect of oven drying on physicochemical and nutritional properties of wheat germ. For this purpose, raw and processed (160oC for 20 min) wheat germ were evaluated for their proximate composition, mineral profile, fatty acids profile, total phenols, flavonoids and antioxidant activity. Results indicated that the raw and roasted wheat germ contain protein (29.5, 30.58%), fat (9.03, 9.16%), fiber (7.21, 7.44%), unsaturated fatty acids consist of 15.86% oleic (15.86, 15.88%), linoleic (55.75, 56.13%), linolenic (8.13, 8.03%) and palmitic acid (20.26, 20.22%), respectively. Minerals analysis was demonstrated that raw and roasted germ had values of iron (166.82, 164.08 ppm), potassium (11083.33, 10750 ppm), calcium (2450, 2441.67 ppm), phosphorus (8316.67, 8333.33 ppm), magnesium (1977, 2011ppm) zinc (203, 204.5 ppm). Besides, it has been shown that during heat processing phenolic and flavonoid contents decreased while, antioxidant activity increased significantly. Based on the obtained results, it can be concluded that application of this nutritious by-product in food industry can be effective in increasing public health.

In this research, the treatment of ozone gas and chitosan edible coating in different treatments were used during palm date storage in order to evaluate the palm date shelf life and decrease it's microbial load. In doing so, the studied dates were treated by ozone in three levels (0, 2.5, 5ppm) for 1 hours, then they were coated by chitosan in three levels (1, 2%) in the form of response surface design.afterwards the packaging was performed by available commercial methods and until the end of experiment, they were kept in three temperatures (5, 15, 25oc).the results of growth of yeast, molds and coliform and total number of bacteria showed that their number is inversely related to increasing the concentration of ozone gas and used chitosan percentage and it is directly related to temperature and storage time with due attention to economic problems, there is tendency to use less concentrations of ozone gas and chitosan edible coating and also palm date storage in room temperature for long periods and based on this, the data were optimized and the values of ozone, chitosan, temperature and time were suggested for 29% humidity date in order 2.01ppm, 0.84%, 22.4oc, and 33.99 days.

Consumption of synbiotic products has beneficial effects on the health of the consumers. The aim of this study was to investigate the effect of Arabic gum (0.1 %), Tragacanth gum (0.1 %) and mixture of them (each at a concentration of 0.05 %) on the properties of yogurt containingLactobacillus casei. The samples of probiotic yogurt were dried by freeze- drier. Water was added to produce powders (The ratio of powder to water was 1: 5). Then, samples were kept at 4 ˚C for three weeks. Physicochemical properties, viability of probiotic bacteria and sensory characteristics of probiotic reconstituted yogurt samples were analyzed on first, 7th, 14th and 21st days. The sample containing mixture of two gums on the first day had the highest count of probiotic bacteria. pH and viscosity of the samples significantly (p<0.05) decreased during storage. Acidity of the samples significantly (p<0.05) increased during storage. There were no significant changes in dried matter and syneresis of the samples during storage. Counts of probiotic bacteria in the samples except sample containing mixture of two gums significantly (p<0.05) reduced. The sample containing Arabic gum had the highest sensory quality. There were no significant changes in flavor, texture (mouthfeel and non-oral sense), color and general acceptability of probiotic reconstituted yogurt samples. The results of this study show that the production of probiotic reconstituted yogurt with desirable sensory quality was possible and use of Arabic gum and Tragacanth gum increases viability of probiotic bacteria in reconstituted yogurt samples.

Nowadays, consumers are applicant to usage of natural replacements causing to side effects of synthetic preservatives such as carcinogenicity and teratogenicity. This experiment was carried out to introduce a new product resulting from dipping of chicken breast meat in pomegranate fruit juice and chitosan coating enriched withZataria multiflora Boiss essential oil. Treatments of the present study were the following: control, samples containing pomegranate juice, samples containing chitosan, samples containing pomegranate juice and chitosan, samples containing pomegranate juice and chitosan enriched with essence 1%, samples containing pomegranate juice and chitosan enriched with essence 2%. The samples were stored at -18±1oC for 6 months and microbial analyzed at 0, 2, 4 and 6 months. Population of mesophilic total plate counts, Pseudomonas spp., lactic acid bacteria (LAB), Enterobacteriaceae, Psychrotrophic bacteria and yeasts-molds were significantly (P<0.05) lower in all of treatments than control until second months of storage. Also chitosan coating enriched with essence significantly (P<0.05) improved all of these effects. Furthermore, the results indicated that the frozen storage deteriorated bioactive compounds of pomegranate fruit juice and therefore dis appeared its antimicrobial effects after fourth months. The results of this study showed that the freezing storage (-18±1oC) can be destroyed the antimicrobial effects of pomegranate juice.

Aerated desserts have shown a great market potential. Mousse is an airy dessert had stable foamy structure. In this study the effect of different concentrations of albumin, sodium caseinate, whey protein concentrate and gelatin on texture feature (stiffness and fractal force), and microstructure (bubble size distribution and equivalent bubble diameter) of chocolate mousse were evaluated. Result of bubble size distribution showed at samples including albumin, most of bubble was in smaller 5 pixel part and section of larger than 20 pixel had low effect on microstructure mousse chocolate. Also samples including high amount gelatin had lesser portion in section on more than 20 pixels. Equivalent bubble diameter increased during aging but samples including albumin and high amount gelatin had little increasing. Totally increasing amount of protein caused equivalent bubble diameter decreased. Stiffness was more in sample including high amount gelatin. Fractal force had no significant different.

Because of the importance of meat and meat products, especially sausage and Ham, and the adverse effects of artificial preservatives used in them, in this study has been investigated the effects of natural preservatives chitosan on the shelf life of heated meat Ham and also has been compared with synthetic preservative sodium nitrite. In this study, heated meat Ham in tow treatments, chitosan 1% and Sodium Nitrite 0.01% in conjunction with the control sample, was quality investigated at the temperature of 4°C during sixty days storage. All samples were analyzed in microbiological determinations, lipid oxidation, pH changes and sensory test. Treatments of Chitosan have significant differences (P<0.05) in the preventing of fat oxidation in comparison with the control sample, While the treatment with sodium nitrite could not establish any significant difference (P>0.05) with the control sample. In microbial study, chitosan treatment could make a significant difference (P<0.05) as the same nitrite in the total count of Mesophilic and psychrophilic microorganisms, mold and yeast than the control sample. Chitosan was cause to control pH changes similar to sodium nitrite. The chitosan treatment had the highest acceptability of color. According to the results of this study, chitosan at Concentration of 1% in addition to having anti-oxidative effects on fat, have the same effect on the controlling of microorganisms in heated meat Ham like sodium nitrite. Also chitosan in this concentration can control the pH change and improve the color of the treated samples.

Bioactive compounds such as polyphenols and fibers in plant products are recognized for their health benefits. In this study, antioxidant activity, polyphenol contents, pigments, and total crude fiber of date pit of Mazafati and Kalutah varieties (Kerman, Iran) were investigated. Total crude fiber, phenolic compounds, and pigments were then determined using fiber tester and spectrophotometric method, respectively. The antioxidant activity was also determined by the scavenging of DPPH (2, 2-Diphenyl-1-picryl-hydrazyl) free radical. Date pits of Mazafati and Kalutah had light to dark brown colour. Total phenolic content of Bam Mazafati, Jiroft Mazafati, and Kalutah varieties were 1898.27, 1840.93, and 1952.93 mg gallic acid equivalent/ 100 g, respectively. The antioxidant activity of pit extracts ranged from 194488.6 to 248166.7 mMol Ascorbic acid/ 100 g. The date pits, on the average, contained 11.72 mg/ ml carotenoids, 4.14 mg/ ml chlorophyll a, and 5.85 mg/ ml chlorophyll b. The total crude fiber was also in the range of 26.18-28.56%. The present study indicated that the date pits of Mazafati and Kalutah varieties had high antioxidant activity and also were a good source of fiber and phenolic compounds. Therefore, date pit can be used in different food formulations and also its extract as an antioxidant in preventing food oxidation is recommendable.

The aim of this research was to produce functional cacao milk by the use of sugar substitutes that its sensory characteristics are similar to cacao milk containing sugar. Rebaudioside A, inulin, oligofructose and isomalt have been used as sugar substitutes in functional cacao milk. After producing 36 functional cacao milk samples with different formulations, treatment T1 (containing 65% rebaudioside A, 5%inulin, 10% oligofructose, 20%isomalt) and treatment T2 (containing 65% rebaudioside A, 10%inulin, 10%oligofructose, 15% isomalt were chosen. The other treatments were not accepted due to the bitter after-taste. The results of physicochemicall tests indicated that viscosity and pH of T1 and T2 samples were higher in comparison with control sample. The viscosity of treatments increased significantly during storage time (p<0.05). The results of pH tests revealed that pH decreased during storage time (p<0.05). There was no significant difference between acidity of samples in 1st and 3rd days (p>0.05). Meanwhiles, acidity of treatments increased significantly during storage time (p<0.05). The results of overall acceptability assessment showed that there was no significant difference between T1 and control treatments, while there was a significant difference between T2 and control samples (p<0.05). Also, treatment T1 gained more score in comparison with treatment T2; so, it can be concluded that treatment T1 was very similar to control treatment and it could be used in producing functional cacao milk.

Millet contains several valuable compounds, therefore is used in different food products. To inves-tigate the effect of replacement of wheat flour with millet flour, 0, 25, 50 and 75% of the initial formula was replaced by millet flour and then chemical properties (protein, fat and ash) of flour mixture were determined. Furthermore, sensory (underscores, and loss of porosity, hardness and softness of texture, chewiness, smell and taste) and texture (hardness and elasticity) of bread sam-ples were determined. The level of fat and ash increased significantly (P<0.05) with an increase in the amount of millet flour but differences between protein quantity of samples weren’t significant. By increasing of millet flour incomposite flour, gluten content decreased significantly (P<0.05). The amount of water required to prepare the dough and thickness of bread samples with millet flour, was lower than control sample. Sensory evaluation showed that the sensory properties of bread samples are inversely related to the amount of millet flour. Bread sample with 75% millet flour, had hard and brittle texture and the taste was quite bitter and astringent. Instrumental texture analysis of bread samples showed that by increasing the amount of millet flour, stiffness and elastic-ity of breads increased and reduced respectively. It seems that the use of millet flour bread in the amount of 25% in the flour formula of Barbari bread is possible and using higher amounts of millet flour is required additional researches to modify and improved bread characteristics.

Main objective of this research was production of high fat yoghurt by partial or complete substitution of milk fat with palm oil. Three different types of high fat yoghurts, including yoghurt containing only 8% milk fat (control) yoghurt containing 4% milk fat and 4% palm oil, yoghurt containing 8% palm oil were produced. Samples kept in 4°C for 28 days and their physicochemical properties determined at the interval of 7 days. The results of statistical analysis showed that the treatment and the storage had significant difference (P<0.05) on PH, acidity and syneresis. The lowest and highest pH level respectively belongs to control sample and the sample with 8% palm oil. During storing period pH level of all samples decreased and the amount of syneresis increased during storage. The amount of dry matter, protein and fat of the samples, did not show a significant difference (P>0.05). Substitution of milk fat with palm oil reduced the levels of saturated fatty acids and short chain fatty acids while the amount of saturated fatty acid of Palmitic acid and unsaturated fatty acids of oleic acid and Linoleic acid showed a significant increase (p<0.05). This study showed that substitution of milk fat with palm oil aspect physicochemical is advisable and can reduce harmful effects of high intake of saturated fatty acids and high cholesterol of milk fat.

The biopolymers based packaging materials containing nano-silver are new types of active packaging that are biodegradable and in addition, they can reduce the risk of microbial contamination in fresh and processed foods. In this research, clay (MMT) nanofillers were used for improving the mechanical properties and water vapor permeability (WVP) of the thermoplastic starch (PS) films and producing nanobiocomposites. In addition, nanosilver (AgNP) was applied for producing active antimicrobial film against Escherichia coli. According to the results of the antimicrobial test, the MMT not only did not show any antimicrobial activity but also reduced it in the films containing nano-silver. AgNP and MMT and their mixture improved barrier properties of the PS based films; In comparison to the control film, the water solubility and permeability of the PS-AgNP-MMT films were reduced about30.93 and 75.43 percent, respectively. The results of mechanical tests showed that in the films containing MMT, increasing concentration of AgNP, increased ultimate tensile strength to 5.38 MPa and reduced strain to break to 41.23 percent. Furthermore, increasing concentration of AgNP in the films containing MMT reduced UV light transmittance significantly however, increased yellowness and turbidity.

The effect of blanching, pre-drying and frying conditions on quality of fried potato strip was investigated. For this purpose, strips with a cross-section of 0.8×0.8×8 cm were prepared and immersed fried in hot oil after performing of each pre-treatment. Pre-treatments were included: 1) blank strips (raw potato), 2) blanched strips in hot water at 70oC for 10 minutes, 3) pre-dried strips at 70℃ with air velocity of 1 m/s until mean moisture content of 75% (wet basis) and 4) blanch and pre-dried strips and frying was carried out in three treatments of: 1) at 160℃ for 5 min, 2) at 175oC for 4 min and 3) at 190oC for 3 min. The results of investigates showed that the minimum of oil content was related to blanch and pre-dried strips in all frying treatments. Blanched strips also had the lowest reducing sugar content and therefore the lowest acrylamide content. Blanching and pre-drying treatment were improved the colorimetric parameters significantly (P<0.01) and blanch and dried strips were showed the more favorable texture properties in all treatments of frying. Increasing of frying temperature increased the oil uptake and intensified the generation of acrylamide in final product significantly (P<0.01).

Deep-fat frying process of foods is one of the common cooking methods. The process causes some changes in physical properties of foods such as apparent density. In this study, the effect of process conditions (temperature and time) as well as ultrasound and microwave pretreatments on apparent density of potato strips during deep-fat frying process was investigated. Ultrasound pretreatment was performed at frequencies of 28 and 40 kHz and microwave pretreatment was conducted at powers of 3 and 6 W/g on the potato slices. Then, the frying process was done at 150, 170 and 190°C for 1, 2, 3 and 4 min. Results showed that ultrasound and microwave pretreatments significantly reduce the apparent density of potato strips compared to control samples. In addition, apparent density was significantly decreased by increasing ultrasound frequency, microwave power, process time and temperature. Furthermore, five models were presented in order to predict apparent density considering the process conditions.

The effect of vacuum packaging on the shelf life of white shrimp (Metapenaeus affinis) treated with and without coating green tea extract (1 g/L) during refrigerated storage (4oC) during 10 days was investigated for determine of peroxide value, thiobarbitoric acid, free fatty acids, melanosis (black spot) and sensory properties. The coincidental lowered rate of increase in peroxide value, thiobarbitoric acid and free fatty acid were obtained in shrimp stored under vacuum packaging (P<0.05). Shrimp processing with green tea extract and vacuum packaging decreased chemical changes and melanosis formation in comparison with shrimp of storage in vacuum packaging and control samples (P<0.05). The results of sensory analysis was showed that the texture, odour, flavor, colour and overal likeness properties decreased gradually in all of treatments and control sample and the sample of vacuum packaging with GTE was the best than samples of vacuum packaging without GTE and control. Therefore, shrimp treated with green tea extract prior to vacuum packaging had the highest of time storage during refrigerated storage.