مجله علوم و صنایع غذایی ایران
سال شانزدهم شماره 1 (پیاپی 86، فروردین 1398)

Evaluation of the antimicrobial activity of plant extracts and essential oils has grown dramatically in recent years. In this study, the antimicrobial effect of Cardin extract (Biarum bovei) in vitro and hamburger on Escherichia coli and Staphylococcus aureus bacteria and total countt is investigated. At first, different concentrations of Cardin hydroalcholicextract was prepared. Antibacterial effects of extracts were evaluated by agar method (disc and wells), minimum inhibitory concentration and minimum bactericidal concentration (by dilution method) and time-killing curves. Antimicrobial activity of extract against Escherichia coli, Staphylococcus aureusand its effect on total microbial count in hamburger at -12 °C during storage (0, 15, 30 and 45 days) was studied. In diffusion method, with increasing concentration, the diameter of inhibition increased. MIC of extract for Escherichia coli and Staphylococcus aureus, was 25 and 12.5 mg/ml and MBC was 50 and 50 mg/ml, respectively. After treatment the hamburger samples with different concentrations of the extract, it was found that antimicrobial activity increased with increasing the concentration and decreasing the temperature. Thus, it can be concluded that hydroalcoholic Cardinextract can be replaced by synthetic materials as a natural antimicrobial compoundto improve durability.

Recently, due to healthier and nutritional problems of synthetic antioxidants in food processing, using of herbal medicine and its effective components as a natural resources with antioxidant properties have been evaluated. This study was accomplished in order to examine phytochemical and antioxidant capacity of different small fruits in 15 accessions (Physalis, Solanum luteum, Raspberry, Hawthron, Barberry, Rose and Elderberry). After species identification, extraction of samples was conducted using ultrasonic device. Total phenolic content, total flavonoid content, total carotenoid and chlorophyll and Antioxidant capacity were determined by using Folin–Ciocalteu assays, aluminum chloride method, Lichtentaler method, DPPH respectively. The results showed that significant difference (p≤ 0.01) among small fruits phytochemical properties. Total phenolic content was in its highest value (5.096 mg GAE/g FW) in the genotype of G3 (Rubus ulmifolius sub sp. sanctus), whereas the lowest level (0.315 mg GAE/g FW) was found in the genotype of G1 (Physalis alkekengi). Total flavonoid content was in its highest value (14.433 mg /100g FW) in the genotype of G3 (Rubus ulmifolius sub sp. sanctus), whereas the lowest level (0.8 mg /100g FW) was found in the genotype of G1 (Physalis alkekengi). The highest level of total carotenoid content (20.508 μg/g FW) was found in G13 (sambucus nigra marginata). The highest level of antioxidant capacity in DPPH assays (Rubus ulmifolius sub sp. sanctus) were found in G3 (86.634 %). These results showed that different small fruits especially Rubus promising sources of natural antioxidants and other bioactive compounds beneficial to be used in the food or the pharmaceutical industries.

In this study, the effects of Allium iranicum adding to yogurt were studied to improve the quality and shelf-life of the product. Allium iranicum powder was used in 3 levels of 0.5 %, 1.25% and 2% in the production of stirred yogurt. Two quantitative factors such as concentration of Allium iranicum powder and storage time were investigated using a growing factorial design with central points. After collecting data, analysis of variance and linear regression were used to investigate the effects of factors and their significance. After data modeling, the effects of powder percent and storage time on physicochemical properties (pH, acidity, WHC, antioxidant property, synergistic, dry matter, viscosity, color properties and sensory properties) were investigated. The results showed that with increasing the percent of Allium iranicum powder, the acidity of the samples increased during storage and the dry matter increased with increasing the concentration of Allium iranicum powder. Viscosity, WHC, synergy and sensory and colorimetric properties were desirable in lower levels of Allium iranicum powder. Antioxidant activity increased with increasing powder percent and decreased during storage time. The highest total acceptance of yoghurt samples was for samples containing powder (1.25%) and 2% showed a negative effect on sensory function. According to the results, it was found that the Allium iranicum powder at 1/25% level could improve the properties and durability of yogurt samples.   [1] Water Holding Capacity

In this research, total phenolic content, total flavonoids content and total antioxidant activity of defatted sunflower seeds were evaluated. The antioxidant activity was determined using scavenging capacity of diphenyl-1-picrylhydrazyl. The results showed that the extraction of phenolic compounds, flavonoids and free radical-gathering capacity depends on the type of solvent, temperature, and time of extraction. So that the content of the total phenol content, and antioxidant activity (152.026 mg/g and 97.760 %) of the extract of the seeds were higher at the same conditions (80 , 2h) by methanol, and total flavonoid content (21.5 mg/g) was reported to be higher using acetone as the solvent. According to the obtained results, there was found a linear relationship between the percentage of phenolic compounds and radical scavenging activity and an inverse relationship was observed between the level of flavonoids compounds and total phenol content. The results showed that extraction by methanol at 80 and for 2 hours, resulted in higher amounts of phenolic compounds, therefore; the mentioned extract was applied as the natural antioxidants for comparison with synthetic antioxidants (BHA) in sunflower oil. The results revealed powerful effects of extracted sunflower extracts, in which the samples containing 0.1% of extract, acted similar to 0.01% BHA.

In this study, sesame as a dietary supplement and hydroxypropyl methyl cellulose (HPMC) due to its ability to form a gel network during heating, were added to rice flour for making the flat bread. In order to determine the optimal amounts of sesame paste (in the range of 10-20%) and HPMC (in the range of 0.5-1.5%), in product formulation using response surface methodology (RSM) and central composite design (CCD), five levels of these two variables were selected and 12 baking tests were performed. Three qualitative parameters in the product, including compression stiffness, overall consumer acceptance and penetration hardness, were evaluated as responses. According to the results, sesame paste significantly (P˂0.05) reduced the quality parameters and HPMC only slightly improved them. The mathematical models obtained in this study can accurately predict the responses. Correct matching between predicted responses and the results in optimized bread, containing 10.3% sesame paste and 1.5% HPMC, indicates the high capability of RSM to optimize the formulation of gluten-free products.

Pomegranate seed oil (PSO) is an edible oil extracted from industrial wastes of pomegranate processing presented a wide range of biological effects because of its high punicic acid and polyphenolic compounds. Due to its low solubility and high oxidation sensitivity, nanoemulsion (NE)-based delivery systems are recommended to use this oil in the food and beverage industries.  NEs can be fabricated from high-energy or low-energy methods, which each have advantages and limitations. In this study, we compared a high-energy method (sonication) with a low-energy method (spontaneous emulsification) to form PSO NEs based on mixed non-ionic surfactants (Span 80, Tween 80). The effect of surfactant concentration on NE droplet size showed that both methods were able to produce emulsions with ultrafine droplets (d < 150 nm), but the low energy required higher surfactant. Moreover, the effect of various storage temperatures (4, 25 and 55 ºC) on the physical stability of the selected NEs highlighted the stimulated droplets coalescences at higher temperature (55 ºC) leading to relatively unstable NEs in contrast to complete stable ones achieved at mild condition (4 ºC). Furthermore, the oxidative studying (30 days) showed that NE produced by high energy method was significantly (p<0.05) more sensitive compared to similar counterparts formed by low energy method.

Millet is one of the cereals that used in the preparation of gluten-free products for celiac patients. Physical modification methods such as heat-moisture treatments and microwave can be used to improve the performance of gluten-free flours in the baking industry. Millet seeds have limited shelf life in normal storage condition due to its relatively high fat content and high activity of lipase enzymes. In this study Heat-moisture treatments at different levels of moisture (11,15 and 20%) and two different temperatures (90 and 110°C) for 3 hours in oven and microwave treatment at different levels of moisture (11,15 and 20%) were used at different times (30,60 and 90S) with a constant power of 900 W. Then, in order to ensure the effect of the above treatments, the amount of free fatty acids of the treated flours was measured every 10 days as well as the level of lipase activity on the first day and after 30 days. In the heat-moisture treatment, the rate of inactivation of the lipase enzyme increased with simultaneous increase of moisture and temperature of the oven as well as in the microwave treatment with simultaneous increase of moisture and microwave time and the amount of free fatty acid flour during 30 days of storage was reduced. The highest rate of inactivation of lipase enzyme and the least change in the free fatty acid content of flour in heat-moisture and microwave treatments were observed in treatment with 20% moisture content and 110°C, and treatment with 20% moisture and 90S.

In this research to model the process of extracting oil from Niger seeds using the combinational pretreatment of microwave-pulsed electric field three microwave time levels of (0, 100, and 200 seconds) and three electric field intensity levels of (0, 2.5 and 5 kV/cm) were used and after applying these pretreatments, the oil of seeds were extracted using the screw press with different speeds (11 to 57 rpm) and the efficiency of oil extraction process, density, color, oxidative stability, phenolic compounds and protein amount of meal were considered. The artificial neural network tool was used to predict the variations process. Through studying and examining various networks, the feed forward back propagation network with 6-9-3 topologies and with correlation coefficient of more than 0.995 and mean squared error less than 0.001 using logarithm sigmoid activation function, resilient learning pattern and learning process of 1000 were determined as the best neural method. On the other hand the results indicated that an increase in the microwave time and also in the electric field intensity at first led to increase in the efficiency of oil extraction process but with more increase in these two parameters the efficiency amount of oil extraction process was decreased. Also with increase in the microwave time, electric field intensity and the rotational speed of screw press the acidity amount of oils was increased too. The results obtained from selected optimized models were evaluated too and these models with high correlation coefficient (over 0.918) were able to predict the variation process of oil samples produced using microwave-pulsed electric field pretreatment.

Recognizing the relations between different variables of fat replacing, modeling could contribute to an optimum control of the process and accordingly improve the quality of the final low fat product such as yogurt. In the present study, the Response Surface Methodology (RSM) and Central Composite Design (CCD) has been applied to investigate the effects of different concentrations of inulin (0, 3 and 6%) as a fat replacer, heat treatment (70, 82.5 and 95°c) and various shear stresses using a stirrer (3000, 6000 and 9000 RPM) on gelling properties of yogurt and also different quality attributes of a low fat yogurt. The equations obtained from the study showed that undependent variables had significant effects on the measured attributes (p<0.05). The most effective factor was inulin concentration that improved the low fat yogurt texture, although higher concentrations had negative effect on sensory properties and color. On the other hand, heat treatment had significant effect on gelling ability of yogurt. In sum, sample with 3% inulin, processed at 82.5°C and stirred at 6000 RPM was selected as optimum condition for prebiotic yogurt processing by inulin.

This study was conducted to investigate the content of phenolic compound and radical scavenging capacity (IC50) of chevil as a replacement for synthetic antioxidants. The extract of chevil leaves powder  was obtained by maceration (12 h)  and microwave (60 s) with ethanol or water  (100: 0, 75: 25 , 50:50) and the amount of  total phenolics and flavonoids was measured by spectrophotometry and antioxidant activity was measured by scavenging free radical 2,2-diphenyl -1- picryl hydrazine (DPPH). Data were analyzed by SPSS versiov 24 as well as variance analysis. The results showed that there was a significant difference between the extracts obtained by two used solvents ethanol and water (p<0.01). The extracts obtained by microwave showed the highest flavonoids content (0/75±0.008 mg Eq. Rutin/g dry sample) and the highest radical scavenging activity (1/04 ± 0/1) at ethanol to water ratio of 0:100 % as comared to maceration method. In contrast, the highest total phenol content (TPC) (3/665±0.09 mg Eq. gallic acid / g dry sample) was obtained by maceration at ethanol to water ratio of 0: 100%. For both methods, the rate of extraction was affected by solvents  ratio and water was more effective than ethanol.

The decay of green and blue molds of Thomson navel oranges is one of the main causes of this product's decay and it can be a limiting factor in storing fruits. The aim of this study was to investigate the effects of wax, hot water, calcium chloride and commercial Tecto 60 fungicide treatments on reducing decay by inducing biosynthesis of flavonoid compounds and maintaining the postharvest quality of Thomson navel orange fruits. Fruits kept for three months in a cold storage at a temperature of 5 to 7 °C and a relative humidity of about 75 to 90%. Weight loss of fruits in waxed fruits was significantly lower than other treatments. The wounded and infected fruits did not have much chance of survival. None of the treatments were significantly effective on control of decay of non-wounded fruits. Total phenol content of fruit peel and flesh  decreased during storage. Hesperidin in the peel was at the highest level in Britex wax treatment. The highest amount of scoparon of fruit peel and flesh was in hot water and calcium + wounded treatments, respectively. Although the amount of scoparon in some treatments inhibited the germination of fungal spores, it did not have the expected effect in controlling decay. The use of Tecto 60™ and hot water can significantly reduce the decay of wounded and infected fruits. The treatments were not effective in controlling the deterioration of intact fruits, which indicates the importance of preventing mechanical damage to the fruit in the pre-harvest stage.

Noughl (sugar coated almond or walnut) is a traditional confectionary sugar-based product which is also produced by addition of spices and dried damask rose in recent years. In spite of its popularity, noughl suffers from dehydration in a short time after being exited from the package. Thereupon, the aim of the present study was to investigate the additives' impact (cinnamon, damask rose and saffron) on physico-mechanical properties (moisture content, texture, surface area, color and aw) of noughls and also the trend of moisture loss during storage. The results indicated that the most moisture loss took place at the first 3 days after opening the package. Based on the rheological tests, the highest and the lowest breakage energy belonged to damask rose (35.48 N.mm) and cinnamon (9.1 N.mm) noughls, respectively. Besides, it was found that storing for 14 days led to increase of vanilla noughl firmness for more than three times. Moreover, mean value of water activity of noughls was lower than 0.56. Comparison of mean value of the color total difference (ΔE*) at 0 and 21st days declared that cinnamon and vanilla noughls had the highest and the lowest color alteration, respectively. According to image processing analyses, suitable indicators to show color changes during time were a* and L* channels for cinnamon and damask rose noughls and b* and L* channels for saffron and vanilla noughls.

Today, Melissa essential oil has been drawn a lot of attention in food researches. This essential oil has good antioxidant and antimicrobial activity, so it is a good candidate to incorporate in the nutritional and biological systems. The aim of this study was to investigate the release of Melissa essential oil (encapsulated via isolated proteins and sodium caseinate) in yoghurt by dispersive liquid-liquid microextraction (DLLME) /gas chromatography technique. In this study, yogurt samples with different percentages of essential oil (0, 0/75, 1/5 g/l) were prepared by sonication method. The effect of two factors, including storage time (1, 11 , 21 days) and the percentage of encapsulated essential oil on the gas chromatography profile were studied based on the central composite design (CCD). 10 grams of yogurt samples containing various percentages of essential oil was centrifuged and the liquid part was passed through a sterilization filter. The released essential in the yogurt was extracted (from the liquid part) by DLLME method and was injected into the gas chromatography and its chromatographic profile (total peak area and total peak height) was investigated. The results show that there is a significant relationship between the total peak area and the amount of essential oil released into the yogurt. By studying total peak area in chromatography, it is possible to estimate the amount of essential oil released into the yogurt sample, and it is possible to study the rate of release.

Synthetic colors are additives which can affect the health and safety of food directly. As a result of the increase of synthetic dyes usage in industry and harmful effects of excessive consumption of synthetic colors on human health, we have attempted to propose a valid method by the simplest laboratory equipment for control dose of synthetic colors in foods. In this study, we have selected ice products as the real sample because of its simple matrix. Here, we have attempted to the determination of all allowed synthetic colors in ice samples as individual and mixtures of them (yellow-red, yellow-blue and red-blue) in one run simultaneously. All validation parameters of the method were calculated for each color and compared with international standards. Obtained results are in accordance with international standards and confirm that this method has a good potential to apply as a valid laboratory method not only for qualitative but also the measurement of synthetic colors in food.

In this research, the effect of microwave pre-treatment on qualitative characteristics and sensory properties of air-dried potato sticks was investigated. Different powers (180-900W) and times (1-5 minutes) of microwave were used before air-drying of samples. The moisture content, rehydration, shrinkage, browning, colour indices and sensory properties (taste, colour, shape, strength, and total acceptance) of potato samples were evaluated after the drying process and the response surface method (RSM) was used to determine the optimal conditions for the microwave pre-treatment. Used for the highest levels of physicochemical and sensory properties. The results showed that, with increasing the power and time of the microwave oven resulted in an increase in the moisture content, shrinkage, rehydration and total colour change of the samples. Sensory evaluation results showed that in the microwave pre-treatment, only the scores of the taste and colour of potato samples were influenced by the microwave power and time. According to the results of optimization by the surface response method, the power of 180 Watts and the time of 3.5 minutes for the microwave pre-treatment were introduced as optimum conditions.

Kefir is a traditional beverage that is produced by fermented milk with kefir grains, Kefir grains are complex mixture of bacteria, yeasts, and polysaccharides produced by this micro flora. The initial amount of kefir grains used to produce kefir drinks affects the quality of the beverage in terms of pH, viscosity and microbial characteristics of the final beverage. In this study, the effects of different levels of starter (4, 6 and 8%, containing Streptococcus thermophilus, Lactobacillus delbrueckii subsp. Bulgaricus, Bifidobacterium), yeast Saccharomyces cerevisiae (2, 3 and 4%) and storage time (24, 48 and 72 hours after inoculation) on the physicochemical and microbiological properties of kefir beverage was studied using a central composite design and response surface methodology, in order to produce a product with higher probiotic bacteria than yeast. Physicochemical properties including acidity, pH, ethanol, apparent viscosity and flow behavior parameters, as well as microbial counting was performed. According to the results of the tests, the amount of yeast had the most effect on apparent viscosity and by increasing the amount of yeast and during of storage time, the apparent viscosity and consistency coefficient decreased. In addition, the viscosity increased with increasing starter rates. Regarding the amount of ethanol, the amount of produced ethanol increased by increasing the amount of yeast and during the storage time due to the increase in the amount of yeast and finally the microbial count decreased during storage. Optimization results showed that the sample containing 2% yeast and 4% starter in time 38 hours after inoculation had the lowest amount of ethanol and was suitable for rheological properties.

Nowadays, cakes play an important role in feeding the people around the world, so that the wide types of cakes with the variety of flavors and nutritional value are produced. In this study, wheat flour was substituted with Phaseolus vulgaris flour at different levels (0, 15, 30 and 45 wt%) in order to enrich the cake. Also, some physical and sensory properties of the dough and cake were evaluated. The results showed that with increasing the level of Phaseolus vulgaris flour, the consistency of the dough and the moisture content of the cake samples were significantly reduced (P <0.05), while the minimum specific volume of the cakes was obtained when 15% of the wheat flour was replaced with Phaseolus vulgaris flour. According to the sensory evaluation results, the highest acceptance points were obtained for the control sample and the sample containing 15% Phaseolus vulgaris flour. Based on the results of this study, the sample containing 15% Phaseolus vulgaris flour had the best qualitative and sensory characteristics. Therefore, by replacing 15% wheat flour with Phaseolus vulgaris flour, a nourishing sponge cake with sensory and physical characteristics similar to the control sample could be produced.

Nowadays, modifying of the functional properties of proteins by proteolytic enzymes is a novel way in order to use the hydrolysates as a natural antioxidant, emulsifier or foaming agent. In this study, TSP was hydrolyzed by commercial trypsin (porcine), trypsin extracted from Caspian Kutum, pepsin, alcalase and papain. The results showed that the highest degree of hydrolysis (DH%) was related to commercial trypsin (19.34 %), Alcalase (16.04%) and Kutum trypsin (14.29%), respectively. The highest emulsifying capacity was obtained by commercial and Kutum trypsin, compared to non-hydrolyzed protein, and Alcalase hydrolysates had the highest emulsion stability (p <0.05). Higher foaming capacity was observed in hydrolysates by commercial trypsin, followed by Kutum trypsin, compared to non-hydrolyzed protein. However, the lowest value was related to Alcalase. In the case of foam stability, the commercial trypsin hydrolysate had the most stable foam, while Kutum trypsin, despite its lower efficiency compared to commercial trypsin, had the second place. Hydrolysates prepared with Kutum trypsin had the highest DPPH-scavenging ability and reducing power but the lowest OH-radical scavenging power. The results of this study show that kutum trypsin can produce soy protein hydrolysates with good functional and antioxidant properties, which are comparable to commercial enzymes.

In this research, the Carum copticum essence (0.25, 0.5 %) and beta-carotene (0.015, 0.03 %) in the film containing citric pectin were used to modify and determine the functional properties of the films. The dependent variables included moisture content, thickness, water vapor permeability, antioxidant properties, color indexes and microbial properties. The results showed that adding Carum copticum essence and beta-carotene reduced the amount of moisture significantly, the lowest amount of moisture was in the film contained the highest amount of essence and beta-carotene. The thickness of the films decreased significantly with the addition of essence and beta-carotene. The water vapor permeability increased and decreased by adding essence and beta-carotene, respectively. Addition of Carum copticum essence and beta-carotene increased the antioxidant properties of the films. The lightness parameter increased in films containing Carum copticum essence. Addition of β-carotene to 0.015% reduced the amount of lightness, but at higher concentrations, the lightness increased significantly, in the other hand Yellowness index was increased by adding beta-carotene and whiteness index decreased. In terms of microbial properties of the antimicrobial effect of Carum copticum essence on B. cereus was more than E. coli. Due to the fact that the beta-carotene pigment in different conditions changes the color of food products, the films will be used in intelligent packaging of food products.

In this research, bioaccumulation of ten metals (As, Fe, Hg, Zn, Pb, Se, Cd, Cu, Mn, Ni) in muscle tissue of 30 Common carp (Cyprinus carpio) Caught with cast net from Siah Darvishan River, Guilan province, Iran in the summer season of 2016 were investigated by Varian Atomic absorption spectroscopy. The lowest and highest mean concentration of metals were found, as follows: Zinc 30.81 - 33.19, Iron 26.47 - 31.33, Copper 3.97 - 4.62, Lead 0.79 - 0.95, Arsenic 0.73 - 0.82, Manganese 0.59 - 0.68, Selenium 0.49 - 0.57, Cadmium 0.17 - 0.18, Nickel 0.16 - 0.18 and Mercury 0.08 - 0.09 microgram per gram dry weight, respectively. According to the results of this study, mean concentrations of all elements in the muscle tissue of Common carp, except for Arsenic (0/774 ± 0/047), Lead (0/852 ± 0/084) and Manganese (0/642 ± 0/045) were observed to be lower than determined threshold limit value of FAO/WHO international standard.

Most of the food packaging materials are produced from nondegradable polymers which has become a serious environmental problem. Natural ingredients based on polysaccharides, offer an alternative for synthetic packagings that minimize the environmental pollution with a relatively low cost. The aim of this study was to evaluate the effect of solid lipid nanoparticles (SLN) on morphology, mechanical and barrier properties of sodium alginate film. For this purpose, the nanoparticles were added at concentrations of 0.025%, 0.5% and 0.1% into the alginate films and optical properties, tensile strength, elongation at break (%), Young’s modulus, water vapor permeability (WVP) and the nano-structured of films were evaluated. As SLN concentration increased,  elongation at break and WVP increased significantly (p<0.05), while no significant differences were found in the tensile strength and Young’s modulus (p>0.05). Films containing a high concentration of SLN (0.1%), were slightly yellowish in color and their opacity value increased significantly (p<0.05). The scaning electron micrographs showed that addition of SLN resulted in a hole-like structure in the film texture, which increased with nano-particles, concentration. Results obtained in the present work exhibited that the incorporation of SLN in alginate film was suitable for increasing the film flexibility but it had no positive effect on the film barrier properties.

​  The aim of this study was to investigate the quantitative and qualitative changes of the canned Fesenjan fatty acid composition during the process and the shelf-life, as well as physicochemical properties of this canned food and the extracted oil during the cannery process and storage. Samples were tested after 23, 45, 68 days at 55 ° C which were equivalent to 6 months, 12 months and 18 months at 25 ° C (reference temperature), respectively. In order to study the effect of heat on canned Fesenjan, samples during the process were also studied.  After sterilization of canned Fesenjan, the amount of acidity, peroxide, moisture, and darkness grew and phenolic compounds and vitamin A decreased but no significant difference was found between the secondary products of lipid degradation and pH (p> 0.05). During the maintenance period, the initial products of lipid rancidity increased significantly and the phenolic compounds decreased. Other qualitative parameters of fat did not show any significant difference (p>0.05). The best sample in terms of organoleptic indexes was for the sample after 23 days of storage at 55 ° C (equivalent to 6 months of storage at 25 ° C).The results showed that the sterilization process increased the ratio of omega-6 to omega-3 which is not good for health.  According to the research, the best date for using canned Fesenjan, based on the parameters studied, was reported 6 months at ambient temperature, but preserving the canned Fesenjan for 18 months is also possible.

In this research, the effect of whey protein concentrate (WPC) in the concentrations of 13, 16 and 19 percent with some of stabilizers including carboxymethyl cellulose (CMC), pectin and chitosan on the physicochemical properties such as acidity, pH, viscosity, overrun and melting resistance, as well as sensory properties such as taste, texture and overall acceptability in frozen yogurt were investigated. The results of statistical analysis showed that the effect of experimental treatments was significant (P<0.01) on all characteristics evaluated. By increasing the concentrations of WPC, increased the acidity and viscosity of the samples containing all three types of stabilizers, but decreased the pH, overrun and melting resistance percentage of frozen yogurt samples. The samples of frozen yogurt that enriched with carboxymethyl cellulose showed higher viscosity value than samples containing pectin and chitosan, but maximum percentage of overrun and melting resistance was observed in samples containing pectin. In evaluating the sensory characteristics, frozen yogurt containing 13% WPC and pectin had the highest score. According to the results of the physicochemical and sensory properties of frozen yogurt samples, the combination of whey protein concentrate with a concentration of 13% and pectin stabilizer was selected as the superior treatment.

The aim of this study was to investigate the effect of Aloe vera gel (50 and 100% w / w), salicylic acid (0 and 2 mM) and thyme extract (0, 0.1 and 0.5% v / v) on shelf life of fresh pistachios. Disk diffusion test was done in a completely randomized design and the percentage of Aspergillus development, microbial count, sensory evaluation and color tests were assessed in a factorial based on a completely randomized design. The results showed that the mold growth development (in disk diffusion test) and total counts of mold, yeast and aerobic mesophilic bacteria were lower in the samples containing Aloe vera gel, salicylic acid and thyme extract. Also, the highest score and color parameters in color and sensory evaluation tests were found for the samples with above mentioned coating, which had a significant difference with the control (P <0.05). Control and treatment with Aloe vera gel of 50% concentration (a) were identified as the worst coatings, and Aloe vera gel coating containing thyme extract and salicylic acid at high concentrations (AST) were found to be the best treatment with the ability to improve the shelf life of fresh pistachios.

Today one of the most important concerns of the world is the significant volume of waste accumulation associated with the synthetic polymers used in food packaging. Therefore, biodegradable edible films are the best alternative for synthetic polymers and plastics. In this study, biodegradable films of corn zein containing two levels of olive leaf extract (10 and 15% w/w) are produced and their physical, mechanical, colorimetric and micro straucture properties were investigated. The results showed that the effect of treatment on physical, mechanical and colorimetric properties was significant (p <0.05). The results showed that by adding 15% extract, the thickness and moisture absorption increased compared to the control sample. Also, by increasing the percentage of olive leaf extract, there was a significant decrease in solubility and vapor permeability in all three relative humidity (33, 50 and 75%) compared to the control sample. In conclusion, it can be concluded from the results of this study that the combination of olive leaf extract with polymeric zein improves some physical and mechanical properties of edible film

Industrial lemon juice may contain unauthorized additives that can lead to various diseases in society. As a result, it is highly important to use effective methods to identify the fake lemon juice. In this study, for the first time in our country, detection of cheating in industrial lemon juice in Golestan province is presented by analyzing organic acids, including citric acid, isocytic acid, malic acid, and also determining the ratio between citric acid and isocytic acid using liquid chromatography-mass spectrometry. The accuracy of the proposed method was confirmed by analyzing natural lemon juice samples. The limits of detection and quantification were 2 and 5, 0.02 and 0.05, 0.2 and 0.5 mg L-1 for citric acid, isocytic acid, malic acid, respectively. Industrial lemon juice samples were selected from commercially available brands, and fake samples were detected by comparison of the amounts of organic acids with the authorized values set by the European Standard. The results showed that the proposed method is very effective and sensitive in detecting cheating samples of industrial lemon juice.

According to various reported problems, consumers' interest for using natural food additive and preservative agents instead of synthetic ones has become inevitable. In this paper, after determining the total phenolic compound, antioxidant activity of samples was investigated using three various methods of DPPH, FRAP and B-carotene bleaching power, and then, total tocopherol of the samples was measured. Results proved that ultrasound was able to extract more phenolic compounds than subcritical fluid extraction. As the result of that, US-extract expressed more antioxidant power than SFE-extract in all three antioxidant assays. Comparing antioxidant power of both extracts with synthetic antioxidant (TBHQ) proved various results in different concentrations. A part from antioxidant activity, antimicrobial activity (MIC-MBC) of extracts examined on four various bacteria of both gram positive and negative pathogenic ones. Results detected that 500ppm (the lowest concentration of this work) was the same concentration for both MIC and MBC assays.

Essential of replacing natural compounds with synthetic ones has become more important. Participation of phenolic compounds in natural plant sources in antioxidant and antimicrobial activities caused to determine not only total phenolic and tocopherol compounds, but also antiradical capacity via three various methods such as free radical scavenging DPPH, ferric reducing power FRAP and beta carotene bleaching power of maceration (SO) and subcritical water extraction (SWE) methods of cinnamon extract further than antimicrobial properties of it on both gram negative and positive bacterium. Results proved various amounts with significant difference of total phenolic and tocopherol compounds of two various extraction methods. While SO-extract contained higher phenolic compounds, higher total tocopherol compounds were measured in SWE-extract. Results of all three antioxidant assays indicated that both extracts proved different antioxidant power comparing with TBHQ. The lowest concentration of SO-extract (500ppm) had a bactericide effect on all investigated bacterium in this work. Whereas, 500 ppm of SWE-extract was able to effect only Staphylococcusaureus as a gram positive bacteria, but not others.

A kinetic analysis was performed to evaluate the antioxidant behaviour of luteolin in the triacylglycerols of olive (TGO) and canola (TGC) oils. The process was performed at high (kinetic regime) oxygen concentrations at at 60, 80, and 100 °C in the dark. Different kinetic parameters were determined, including the stabilization factor F, the oxidation rate ratio ORR, the antioxidant activity (A) and the mean rate of inhibitor consumption WInH. The oxidative stability measures of the bulk olive and canola oils dramatically improved by the antioxidant added. Luteolin due to its increased partitioning at water-oil interface exerted a highest activity at 60°C and a concentration of 0.02%. Also, the rate of olive triacylglycerols oxidation increased significantly with increasing luteolin concentration at the corresponding temperature. This behaviour was explained in terms of a more participation of antioxidant molecules and radicals in side reactions, i.e. 10 and 11 ( and , respectively). The rate constant of antioxidant consumption in side reaction(s) (Keff) and mean rate of initiation (Wi/f) values revealed that luteolin takes part in chain propagation and initiation reactions to a higher extent during TGC oxidation. Generally, the activity of luteolin increased and decreased, respectively, in TGO and TGC with rising temperature. This behavior was attributed to the change in the mechanism of inhibitory action with prevailing the reactions 7 ( , 8 ( ), and 9 ( ) for olive oil, and pro-oxidative side reactions to a higher degree in TGC.

Carrot PomacePowder(CPP) is one of the wastes that will be obtained during carrot processing so because of desired nutritional composition (especially fiber and salts); it can be used to increase the nutritional value of gluten-free bread. The purpose of this study was to investigate the effect of CPP(0- 30%) on the physico-chemical, textural and sensory properties of gluten free bread based on the replacement of gluten-free flours(chickpea flour, Rice flour and corn starch) for celiac diseases. The results showed that the water activity, moisture, ash, a* value, fiber, protein and antioxidant capacity of samples containing CPP was significantly higher than the controlones(P<0.05). Increasing of CPP decreased carbohydrate, calorie, L* value, specific volume and fat of gluten-free bread samples. With replacement of CPP in bread formulation, cohesiveness increased but firmness, springiness, gumminess, chewiness and resilience of samples decreased. According to the sensory evaluation, substitution of CPP up to 30% increased the overall acceptance of samples. Generally the results showed that the sample containing 30% CPP had better quality than others, and CPP is suitable factor to increase the nutritional value of gluten-free bread.