IRANIAN JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
Year:2020 | Volume:17 | Issue:100 |Papers Count:19

Nowadays, due to some problems, such as allergic reactions and high fat content, the partial replacement of cow's milk with milk of other animals, such as goat's milk, is so crucial by proper techniques to improve the quality with the aim of yogurt production. The aim of this study was to evaluate the effect of Zataria multifliora and Mentha longifolia L extract (0, 0/02, 0/03, 0/05 ) on the qualitative characteristics of probiotic yogurt produced from the cow-goat milk in proportions 10: 90, 30: 70, 50: 50 and 0: 100. After one day of storage by sensory evaluation, superior samples were selected and qualitative tests were performed within 28 days. The results showed that, over time, acidity and syneresis values increased and pH value, viscosity and probiotic count decreased. The highest viscosity was related to the equal ratio of cow-goat milk and 0/05% of Zataria multifliora extract. The antioxidant activity (AA) trend was irregular but descending and extracts had a significant effect on AA. The treatment of cow-goat milk (10: 90%) and 0/03% of Zataria multifliora extract had the highest probiotic count. The treatment of cow's milk (100%) containing the equal concentrations of two extract (0/02%), showed the highest color, taste, consistency and overall acceptance scores by panelist. As a conclusion, it can be concluded that in order to achieve the best quality of probiotic yogurt, various concentrations of extracts and optimal ratios of cow-goat milk should be used.

The purpose of this study was to evaluate the image processing technique in rice blast disease detection in field and controlled conditions. Using MATLAB software, images taken from field and controlled conditions were processed in three RGB, HSI and LAB color spaces. Then it was extracted by the gray area intensity profile, color properties, and threshold value for background image removal. After removing background in RGB, HSI and LAB color spaces, disease spots on rice leaf were determined. In RGB color space, by subtracting arrays by test and error, the blast patches on the leaf were separated from the rest of the image pixels. Hue was used in the HSI color space because this component was independent of light intensity variations, so blast blot identification was performed more accurately than the S and I components. In the LAB color space, the Kmeans clustering algorithm was used to segment the images into three clusters and was displayed in an independent cluster after labeling the image of blast disease spots. Finally, in order to determine the performance of the algorithms designed in three color spaces, the sensitivity factor, specificity and total accuracy were tested on the basis of the perturbation matrix for 500 image samples. In field and controlled conditions, the highest accuracy in detecting blast blots in the LAB color space was 94% and 98%, respectively. Overall, the results showed that the image processing method can be used to detect rice blast disease.

The most important post harvesting factors that limiting grape berries after post harvesting are water losing and fungal decay. In this study, effect of titanium dioxide (TiO2) and soy protein isolate edible coating against postharvest decay and increasing the storage life of table grape cultivar was investigated. Uniform clusters with no disease and physical damage were packed with coated and uncoated (control) TiO2 nanoparticles. Then clusters were maintained for 31 days in cold storage at 0 ± 1 ° C and RH 90 ± 5%. Grape berries abscission rate, total soluble solids (TSS), titratable acidity (TA), total phenolic content, color and clarity of grape berries, pH, antioxidant activity and total sugar characteristics were measured at intervals 6 days. The statistical analysis of results showed that the TiO2 nanoparticles treatment had significant effects in cluster and grape berries weight losing, fungal infection, TA, total phenol content and coefficient of ripening. This treatment had best flavor, quality, appearance and marketability compared with the samples without TiO2 nanoparticles treatment. In addition, the samples that treated with TiO2 nanoparticles showed higher TSS, TA, antioxidant activity, total sugar and total phenolic content. In the present study, two varieties of grapes treated with TiO2 nanoparticles in the comparison of control samples had higher quality at the end of the storage period.

Ostrich fillets is highly edible and one of most healthy and the least fat red meat samples. Due to carcass contamination along the slaughter chain, it becomes corrupted by the growth of meat microorganisms during storage. Being biodegradable, edible and efficient have caused edible films to be widely investigated and used as a good replacement for synthetic materials in packaging of food products. In this study a gelatin/frankincense (G/F) bilayer film was produced from gelatin and frankincense monolayers using the casting method in two phases. This research investigated antimicrobial activity of various concentrations of acid ascorbic (0, 1% and 2%) and Hyssopus officinalis oil (0, 0. 75% and 1. 5%) in edible bilayer gelatin/frankincense against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeroginosa. on the other hand, effect of edible film was evaluated on microbial and chemical properties of ostrich meat for 12 day at refrigerator temperature. Diameter of inhibition zone showed that Staphylococcus aureus and Pseudomonas aeroginosa were most sensitive and resistant bacteria respectively. Compared with control sample, two treatments (G/F+2%AA+0. 75%HO and G/F+2%AA+1. 5%HO) decreased total viable count, psychrophilic and lactic acid bacteria significantly (p<0. 05). The result also showed with addition Hyssop oil and ascorbic acid, pH and peroxide values notably reduced compared with pure edible film (without oil and acid)( (p<0. 05). The gelatin/frankincense films enriched with essential oil and vitamin C delayed tissue breakdown, and increases the pH by reducing the bacterial growth. Therefore, antimicrobial edible film containing Hyssop oil and vitamin C as an economical and biodegradable coating has a good potential for increasing the shelf-life of ostrich meat at the refrigerator (4Ċ ) temperature.

Free radicals cause many diseases in human. Antioxidants reduce the risk of cardiovascular disease and stroke by neutralizing free radicals and on the other hand, prevent progression of cancer. The natural antioxidant enhances antioxidant properties of plasma to prevent diseases such as heart disease, cancer, and stroke. Plants are a rich source of secondary compounds, which are the most important natural antioxidants. In this study, Fumaria vaillanti aqueous, methanol and ethanol extracts were used to determine the anticancer effect of extracts on Breast Cancer Cells Lines BT-474, MDA-MB_231 after 24, 48 and 72h. The highest percentage of cell death, according to the MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) technique, has been reported in the aqueous extract on MDA-MB-231 cells after 72 hours at with IC50 of 2 μ g / ml. The results of this study indicate that Fumaria vaillanti shows a significant antioxidant and cell toxicity effect and full potential of extracts can be realized by further studies on animal models and subsequent trials.

To meet the consumer's interests for natural remedies, food and pharmaceutical industries calls for a safe and green methods for food aims extraction. Besides, carrot juice industry, possess high potential for processing the less expensive by-products to extract high-value ingredients named carotenoids. The purpose of the present study was therefore to extract beta-carotene from carrot pomace using green solvent (distilled water containing 2% ethanol and 4% surfactant). Results showed that among the used solvents for one-cycle extraction, 1-propanol and ethanol without significant differences (P> 0. 05) were the most efficient with respectively 0. 56 and 0. 51 mg/g of CP beta-carotene content. Whiles, for four-cycle extraction the ethanol was the most capable (0. 92 mg/g of CP). In addition, the poor ability of 2% ethanol containing distilled water (0. 04 mg/g of CP) was significantly increased in the expense of enzyme hydrolysis via Endozym ® Pectofruit(61 U as pectinase activity). Moreover, the 4% of all of the surfactants (soy lecithin, span 20, tween 20 and tween 80) were significantly increased the extraction capability of the green solvent, wherein, the highest beta-carotene content was extracted with tween 80 (0. 29 mg/g of CP). As well, all surfactants showed synergistic effect with enzyme pretreatment resulting up to 62% efficiency for tween 80 compared to four-cycle extraction with ethanol. All in all, the composed of distilled water: ethanol: tween 80: span 20 (94: 2: 2: 2) led to a green extraction of beta-carotene from carrot pomace with 0. 84 mg/ g of CP beta-carotene content and 90% extraction yield.

In this study, omega-3 fatty acid nanoemulsions were prepared by spontaneous emulsification using Iranian shallot essential oil. The aim of this study was to investigate the optimum conditions for the production of probiotic yogurt enriched with nanoemulsions of essential oil of omega3 fatty acids by using a D-optmal design. Nanoemulsions containing omega3 fatty acids were first produced by Iranian shallot essential oil (25% omega3, 35-day storage time, SOR (263/39) % and surfactant type of tween80), then the probiotic yogurt enrichment with the produced nanoemulsions, the effect of two independent variables of nanoemulsion concentration and storage time on physicochemical characteristics, population growth Probiotics and sensory properties of yogurt were investigated. the results showed that droplet size was highly influenced by surfactant concentration and surfactant type and increasing surfactant content, mean droplet diameter decreased significantly. In fact, increasing surfactant concentration caused to increased surfactant adsorption to W / O level and due to further reduction in surface tension and ultimately reduced the particle size, turbidity index, creaming index and increase coating efficiency, as well as the addition of nanoemulsions in probiotic yogurt on properties such as peroxide index, synersis rate, Population of probiotics and Sensory evaluation were significant, population growth of probiotic microorganisms in yogurt increased in the presence of vegetable nanoemulsions of essential oil due to nutrient availability. Finally, 15 days storage time and 1. 4% nanoemulsions were determined as an optimum formulation by numerical optimization.

During the last decade, application of edible coatings as efficient carriers for the transfer of bioactive compounds including probiotic microorganisms has become more prominent for production of food products with stressful condition for these bacteria. In this study, the effect of optimizing a coating formulation based on carboxymethylcellulose and sucrose as carrier of probiotic strain for rock candy coating was evaluated. Response surface method based on the central composite design was applied to evaluate the coating movement on the rock candy, the amount of coating remaining on the product after immersion and texture characteristics of the coating, such as adhesion. In addition, the textural and rheological properties of the coating solution under different concentrations of carboxymethyl cellulose and sucrose were investigated. The optimized formulation for rock candy coating was obtained with 97. 9% carboxymethyl cellulose and 46. 5% sucrose. The results showed that by increasing carboxymethyl cellulose concentration (from 0. 8 to 1. 2%) and sucrose (from 40 to 50%), the viscosity of the coating solution ranged from 9. 27 to 82. 62 Pa. s. Also, the flow behavior index of the coating solution confirmed the pseudoplastic behavior of the coating at carboxymethyl cellulose concentrations of 0. 8 and higher. While, increasing the concentration of sucrose at a constant concentration of carboxymethyl cellulose had a greater effect on the textural parameters of the coating solution. In addition, the use of Bacillus coagulans spores in this product showed high viability of this strain (more than 90%) under product storage conditions (ambient temperature and dry place).

The plant Stachys schtschegleevii is used in the Iranian traditional medicine for the treatment of bacterial infections, rheumatism fever, and inflammatory diseases. In this study, the maceration extraction method with ethanol and water was used to obtain S. schtschegleevii extract, and extraction yield, total phenol content, and antioxidant and antimicrobial activity of the obtained extracts were evaluated. The extraction yield of S. schtschegleevii ethanolic extract was higher than that of aqueous extract (8. 8± 0. 27 vs. 6. 9± 0. 33%), and its total phenol content was also higher compared to the aqueous one (55. 35± 0. 28 vs. 49. 4± 0. 62 mg gallic acid/g dried extract). Antioxidant activity based on IC50 showed that the ethanolic extract, due to its higher total phenol content, has the ability to deactive and neutralize free radicals more efficiently in comparison to the aqueous extract. Antimicrobial results (disk diffusion agar, minimum inhibitory concentration and minimum bactericidal concentration) indicated that bacteria Staphylococcus aureus, Listeria innocua, Escherichia coliand Pseudomonas aeruginosa were more sensitive to the ethanolic extract, and at the same concentration of ethanolic and aqueous extracts, gram-positive bacteria (Staphylococcus aureus and Listeria innocua) had higher sensitivity than the gram-negative ones (Escherichia coli and Pseudomonas aeruginosa). Thus, S. schtschegleevii extract rich in phenolic compounds with appreciable antimicrobial and antioxidant activity could be used as an ingredient to increase nutritional value and shelf-life of food products.

The aim of this study was to extract and identify the volatile constituents of the essential oils of two species of citrus named Clementine and Mandarin and to investigate their antioxidant and antimicrobial potential. The compounds of the essential oils prepared by steam distillation were identified by gas chromatography-mass spectrometry (GC/MS). The antioxidant abilities of the essential oils were evaluated by DPPH and ABTS assays. The antimicrobial activities of the essential oils were investigated using the disc diffusion method against three Gram-positive (Staphylococcus aureus, Bacillus ceruse, and Bacillus subtilis) and two Gram-negative (Escherichia coli and Salmonella typhi) bacteria, a yeast (Candida albicans) and a fungus (Aspergillus niger) in comparison with the synthetic antibiotics. The both essential oils were rich in hydrogenated monoterpens and limonene was the main compound in both essential oils. The highest percentage of DPPH and ABTS free radical scavenging was shown about 34. 38% and 48. 44%, respectively for Clementine essential oil and for Mandarin essential oil was 67. 53% and 96. 44%, respectively, at 900 ppm. The results showed that both essential oils inhibited the growth of the studied microorganisms and increasing the essential oil concentration, increased the zone of inhibition. The highest diameter of inhibition zone was observed in Candida albicans in both essential oils. The lowest inhibition zone for Clementine and Mandarin essential oils was also observed in Escherichia coli and Aspergillus niger, respectively. In general, the antifungal effect of both essential oils was more than their antibacterial effect. Based on these findings, citrus peel essential oil could be suggested as a natural preservative substance for use in food products.

Biodegradable polymers have supplied most of common packaging materials because they present several desired features. The purpose of this study was to prepare and investigate the physicochemical properties of carboxymethyl cellulose based nanocomposite film containing inulin with three different concentrations (0, 10 and 20%) and cellulose nanofiber in three levels (0, 2. 5 and 5%). Thickness, Water vapor permeability (WVP), Water contact angle, mechanical properties, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction were evaluated for film samples. WVP decreased with adding cellulose nanofiber and inulin and water contact angle increased significantly (p <0. 05). The mechanical properties were also improved by adding the cellulose nanofibers. Whereas inulin had a negative effect on mechanical properties by decreasing tensile strength (UTS) and increasing elongation to break (ETB), this effect of inulin was compensated by cellulose nanofiber in the composite films containing inulin and cellulose nanofiber. The FE-SEM and X-ray diffraction results showed that the cellulose nanofiber and inulin were dispersed in the polymeric matrix and formed a dense and compact structure in compared to the control film. Results showed that cellulose nanofiber and inulin improve the properties of carboxymethyl cellulose based nanocomposites and the obtained film can be used as a new choice in food packaging.

Date Plum (Diospyros Lotus) has high health-promoting properties which they are mainly attributed to its available bioactive compounds. In present study, antioxidant and antibacterial properties of the date plum syrup was investigated and the extract compounds identified by Gas Chromatography Mass Spectrometry (GC-MS). Total phenolic and flavonoid contents and antioxidant activity of the extracts were measured. Antimicrobial activity was performed on four bacteria by disc diffusion method. The research results indicated high total phenolic and flavonoid contents of the date plum extracts. Surveying antioxidant properties of date plum extract also implicate its high antioxidant properties. DPPH radical scavenging activity of date plum extract at concentrations of 800, 400, 200, 100 and 50 micrograms/milliliter has been 82%, 61. 53%, 53. 51%, 32. 52%, 18. 31%, respectively. In investigation of antibacterial properties, the date plum syrup had high inhibiting effects on growth of different types such as Escherichia coli, Salmonella, Staphylococcus aureus and Bacillus cereus in high dilutions (50 and 100 mg/ml). . The date plum extract includes high amounts of sugar and functional components such as 5, 5-Epoxymethano-2, 2, 6-trimethyl-7-oxabicyclo (17/77%), 2-Furancarboxaldehyde (17/01%) and 1-allyl-3-methylindole-2-carbaldehyde (11/2%).

In this study, we try to evaluate the effect of ionic strength, pH and temperature of washing solutions on nitrate percentage in many leafy and root vegetable. For this purpose three edible solutions including NaCl as high ionic strength solution, baking soda (NaHCO3) as basic solution and vinegar as acidic solution selected as nitrate losing agents for leafy vegetables (mint, basil, savory, tarragon, parsley, coriander, cress, radish and chives) and the effect of temperature evaluated using warm water (70-100 ˚ C) on nitrate percentage in root vegetables (potato and onion). Nitrate percentage in vegetables changed with different patterns. High ionic strength increased leafy vegetable nitrate percentage in wide rang (20. 25-85 %(w/w)), pH increasing by baking soda solution increased nitrate percentage of group 1(Mint & Basil) leafy vegetables (33 %(w/w)) and decreased it in other groups partially (0. 22-6. 2 %(w/w)). However, pH decreasing by vinegar solution decreased nitrate percentage in all cases (14. 6-41 %(w/w)). Optimum concentration of vinegar solution and treatment time in this solution, for maximum nitrate losing were 20 % (w/w) and 10 minutes, respectively. In the second part of this study, effect of solution temperature on nitrate percentage of root vegetables (potato and onion) was evaluated. Results show by this pretreatment nitrate percentage decreased 68. 6 %(w/w) about potato and 26. 6% (w/w) about onion. The important advantage of this study is vegetables nitrate percentage decrease, while the freshness and safety of these products preserved.

Walnut Butter is a very valuable product in terms of nutrition that comes from walnut. One of the main problems in the production of such products is the separation of the oil phase in the product. In this research, the amount of water activity and physical stability of walnut (in the presence of 0. 5, 1, 1. 5 and 2% concentrations of monoglycurids, lecithin, spin 80 and tween 20) in 75 days of storage at 25 ° C Reviewed. The results indicated a slight decrease in wold walnut samples containing lecithin, span 80 and monoglyciride until the 15th day, and then showed a roughly constant trend. Lecithin was more effective in reducing the percentage of oil removal during the maintenance period than other emulsifiers, while spin 80 had no significant effect on the stability of walnut emulsion, and tween 20 had a negative effect on the oil removal percentage from walnut during storage.

Drying is one of the ways of storing of persimmon. In this study, to increasing shelf life of persimmon and producing high-quality products, infrared dryer was used and mass transfer kinetics, density, rehydration and color of samples were measured. The results showed that radiation lamp power and distance of lamp from sample had significant effect on the moisture loss kinetics and drying time (P<0. 05). With increasing in radiation power, as well as reducing the distance of samples from the source of radiation, drying time decreased. The average density and rehydration for the dried samples in infrared were 639 kg /m3 and 270 %, respectively. The average calculated color changes (Δ E) for the power of 200, 300 and 400 w were 14. 43, 10. 09 and 20. 04, respectively. The results of modeling by genetic algorithm-artificial neural network showed that artificial neural network combined with genetic algorithm provides better results and with combine them the speed of analysis and accuracy of modeling process increases. Using a network with 15 neurons in the hidden layer and using the hyperbolic tangent activation function and percentage data used to training/validation/testing equal 20/20/60 may be predicted drying kinetics of persimmon.