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Yogurt contains various health‐promoting components such as beneficial bacteria and bioactive peptides. However, plain yogurt is regarded as a poor source of phenolic compounds, vitamin C, and other substances that give a high antioxidant property to the product. Since the objective of this study was to evaluate the impact of the addition of different concentrated sweet pepper extracts (CSPE) to the yogurt milk formulation on some quality parameters of the probiotic set yogurt during 21 days of cold storage. For the production of probiotic yogurt samples, Lactobacillus acidophilus LA‐5 was used as probiotic bacteria. The functional set yogurts containing 5% of yellow, orange, or red CSPE were prepared and compared with probiotic control yogurt (without CSPE). With incorporation of CSPE, a functional yogurt with high viable cell counts of probiotics (>108 cfu/g), appropriate acceptability (acceptance scores more than 7, i.e., good acceptability), and textural quality produced. Fortified CSPE yogurt displayed large flakes with irregular surface and more compact texture as compared to the control sample. Based on the results of the study, the yogurt sample having orange CSPE was selected as the best functional product. After 21 days of storage, orange CSPE had the highest hardness (173.33 mg), consistency (1183.33 mg/s), and probiotic counts (8.3 log cfu/g) than other yogurt samples. [ABSTRACT FROM AUTHOR]

Bell pepper fruits (Capsicum annuum L.) are prone to both physiological and pathological deterioration following harvest, primarily due to their high metabolic activity and water content. The storage of bell peppers presents several challenges, including weight loss, softening, alterations in fruit metabolites and color, increased decay, and a decline in marketability. The application of edible coatings (ECs) is one of the environmentally friendly technologies that improves many post‐harvest quantitative and qualitative characteristics of products. This research investigated the impact of different levels of gum tragacanth (GT) coating (0, 0.25, 0.5, 1, and 2%) on the physiological and biochemical traits of stored bell pepper fruits (BPFs) (8 ± 1°C, 90–95% RH) for 28 days. The results showed the positive effect of coating treatments with higher concentrations of GT, up to 1%. Increasing the concentration of GT to 2% decreased the marketability and quality characteristics of fruits compared to 1% GT. After storage, the physiological weight loss of the fruits treated with 1% GT (10.46%) was lower than that of the uncoated fruits (18.92%). Furthermore, the coated fruits (1% GT) had more firmness, total phenol content, ascorbic acid, and titratable acidity content than uncoated fruits during storage. At the end of storage, the coated BPFs with 1% GT showed higher SOD (97.02 U g−1), CAT (24.38 U g−1) and POD (0.11 U g−1) activities and antioxidant capacity (81.74%) as compared to other treatments. Total soluble solids, total carbohydrates, total carotenoids, pH, malondialdehyde, and electrolyte leakage content increased in coated fruit during storage but were significantly lower than in uncoated fruits. Moreover, the samples coated with GT (1%) maintained good marketability (about 75%), while the marketability of the control (about 40%) was unacceptable. The study shows that GT (1%) coating can be a promising novel treatment option for increasing the storage quality of BPFs. [ABSTRACT FROM AUTHOR]

This study is aimed to develop a novel edible coating based on Plantago major seed mucilage (PMSM) and Citrus limon essential oil (CLEO) to increase the shelf‐life of buffalo meat during cold storage. The CLEO was firstly isolated by the hydrodistillation method, and it contained mainly limonene (40.5%) and carene (15.4%) with remarkable antioxidant activity (55.7%, 63.8%, and 51.85% based on the DPPH‐radical scavenging, ABTS‐radical scavenging, and carotene‐linoleic acid bleaching tests, respectively) and antibacterial effect against some pathogenic and spoilage microorganisms. The CLEO (0%, 0.5%, 1%, 1.5%, and 2%) was then incorporated into PMSM solution to develop a novel CLEO‐loaded PMSM edible coating for improving the shelf‐life of buffalo meat. The edible coating was able to significantly reduce the progression of lipid oxidation (peroxide value) and microbial growth (total viable count, psychrotrophic bacteria, Escherichia coli, Staphylococcus aureus, and fungi) in buffalo meat during storage period of 10 days at 4°C in comparison with the control (noncoated sample). The meat hardness and sensory properties (i.e., odor, color, appearance, texture, and overall acceptability) were also maintained better upon edible coating applications. Based on the results, the CLEO‐rich PMSM edible coating could be applied as a new and effective preservative to improve the stability of meat products to lipid oxidation and microbial spoilage. [ABSTRACT FROM AUTHOR]

Today, food consumers prefer to use the foods that contain natural preservatives. The purpose of this study was to investigate the effect of Qodume Shirazi seed mucilage (QSSM) and lavender essential oil (LO) on the preservation of ostrich meat during cold storage. The chemical compounds of LO were identified through gas chromatography–mass spectrometry (GC/MS). The ostrich meat samples were coated with the mucilage containing the essential oil at concentrations of 0%, 0.5%, 1%, 1.5%, and 2%, v/v. The control and the coated ostrich meat samples were kept at 4°C and analyzed for microbiological (total viable count, psychrotrophic count, Escherichia coli, Staphylococcus aureus, coliforms, and fungi), physicochemical (moisture content, pH, texture, and color parameters), and sensorial (odor, color, and total acceptance) characteristics during 9 days of storage. GC/MS identified 12 compounds in the essential oil, among which linalool was the major one (43.3%). The lightness (L* value) and hardness of all the ostrich meat samples were reduced during the storage. From a microbiological point of view, the cold storage duration for the control and the coated sample without the essential oil was only 3 days, while for coated samples containing 0.5%, 1%, 1.5%, and 2% essential oil, it was 3, 3, 6, and 9 days, respectively. The coated ostrich meat containing 2% LO had an appropriate quality with an expanded shelf life. The results showed that neural network with 10 neurons in the hidden layer had the lowest mean squared error and mean absolute error and the highest correlation coefficient for predicting the quality and microbial properties of the coated meat samples during storage. [ABSTRACT FROM AUTHOR]

In this study, whey powder was used as the basic compound for fermentation culture and the production of bioactive gamma‐aminobutyric acid (GABA) compound. GABA is a nonprotein four‐carbon amino acid that inhibits stress signals by preventing brain signals, reducing stress, and being effective in treating neurological disorders and decreasing the growth of cancer cells. Due to the side effects caused by the chemical type of GABA, the biological production of GABA has attracted. Three levels of whey powder (5%, 10%, and 15%), and monosodium glutamate (MSG) (1%, 3%, and 5%) were selected at temperatures (25, 30, and 37°C) and after fermentation, the presence of GABA in the culture medium was examined by thin‐layer chromatography. The optimal amount of GABA was measured by using high‐performance liquid chromatography. The results of the central composite design of the response surface methodology at a significant level of 95% showed that the optimal treatment was 14.96% whey powder, 4.95% MSG at temperature of 37°C and fermentation for 48 hr and under these conditions, GABA production was 553.5 ppm. The results of the fermented extract tests showed that the highest antimicrobial activity was on Escherichia coli and the highest free radical scavenging was 59.67%. The IC50 level in the Caco‐2 cancer cell cytotoxicity test was 39.5 mg/ml. According to the results, the combination of whey with MSG can be used as a cheap substrate to produce a valuable bioactive GABA product, and the cellular extract of this fermentation can also be used as an antimicrobial and antioxidant compound in food and pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

The effect of Persian and almond gums (0, 0.1 and 0.2% (w/w)) as fat replacers and milk fat (0.4, 0.9, and 1.4% (w/w)) on physicochemical and rheological characteristics and microstructure of low-fat Iranian White cheese was studied. Persian and almond gums both effectively increased moisture-to-protein (M:P) ratio of low-fat cheese samples which in turn led to a significant reduction in the hardness parameters fracture stress and Young's and storage (G') moduli ( p < .05); however, the effect of Persian gum was more pronounced ( p < .01). Gum addition promoted cheese yield and proteolysis rate ( p < .05). Response surface optimization described that supplementation of cheese milk containing 0.9% fat with 0.2% Persian gum and 0.12% almond gum would result in a low-fat cheese with textural properties similar to its full-fat counterpart. Scanning electron microscopy revealed that the fat replacers produced full-fat-like structure in the low-fat Iranian White cheese, when incorporated at the optimum levels. [ABSTRACT FROM AUTHOR]

The influence of fermented whey protein concentrate (FWPC) added before and after formation of cheese curd on the textural characteristics of Iranian white cheese was studied. The FWPC, prepared from whey obtained during cheese making, was added at different levels 5, 10, 15 and 20% (v/v) after (A) or before (B) cheese curdling. The changes in rheological parameters of cheeses were determined before and after 1 month of ripening. It was found that both incorporation level and stage of addition of FWPC (A and B) caused significant effects on texture profile analysis of cheeses. Increasing the level of FWPC in B group, except samples containing 10% FWPC, in contrast with A cheeses led to considerable increase in moisture and decrease in hardness and chewiness. Samples containing more than 15% FWPC had undesirable texture and were too soft. All experimental cheeses exhibited a decline in values for each rheological parameter after 1 month of ripening. PRACTICAL APPLICATIONS Perhaps the biggest story in the dairy industry in the past couple of decades has been the rise of new applications for whey and whey proteins. Once considered a waste product in the cheese manufacturing process, whey and whey protein products today are used for a wide range of functional and nutritional properties. In the cheese industry, particularly in soft cheese varieties, whey proteins have shown good applications to replace caseins as they act as fat replacer and bind more water than caseins, which results in softer cheeses. Therefore, this study was attempted to investigate the impact of fermented whey protein concentrate on textural attributes of Iranian white cheese. [ABSTRACT FROM AUTHOR]

Microemulsions based on their formation mechanism comparing to kinetically stable nanoemulsions are thermodynamically stable. Moreover, water in oil microemulsions could be used for encapsulation of water soluble compounds or preparing low fat products. In this research, we investigated the effects of preparation and formulation conditions on the formation and physical properties of water in sesame oil microemulsions using spontaneous method. Results showed that PGPR comparing to Span 80 formed transparent nanoemulsion with 67 nm droplet size. To investigate PGPR ability for emulsifying higher amounts of dispersed phase, water content increased in fixed concentration of PGPR. Increasing water content (%WOR) from 10 to 50% increased droplet size and viscosity from 53 to 722 nm and from 115 to 183 mPa.s, respectively. By increasing stirring speed to 900 rpm, droplet size decreased to 45 nm, but increasing stirring time to 2.5 hr, droplet size increased to 72 nm comparing to standard conditions. Comparing to pure water dissolving Vitamin C in inner aqueous phase increased droplet size to 171 nm. Practical applications: Water in oil microemulsions fabricated using spontaneous method due to their high stability could be used for preparing low fat products such as seasonings and sauces. In this study, internal aqueous phase increased as much as possible at a fixed concentration of surfactant and factors affecting the emulsion droplet size and consequently their stability were evaluated. Moreover, such emulsions could be used for encapsulating water soluble ingredients such as Vitamin C in aqueous phase. [ABSTRACT FROM AUTHOR]