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The antimicrobial and antioxidant effects of C itrus aurantium L. flowers (Bahar narang) extract ( BE; 500, 1,000 and 2,000 ppm) were studied in traditional yoghurt stew during storage at 4C for 28 days. The contents of total phenolics and flavonoids in BE were 81 ± 1.8 and 46 ± 2.4 mg/g, respectively. I n vitro antibacterial activity of BE showed that BE had a strong antimicrobial activity against E scherichia coli O157:H7, P seudomonas aeruginosa, S taphylococcus aureus and B acillus cereus. Application of BE in traditional yoghurt stew decreased the growth rate of all tested pathogens and P . aeruginosa was the most resistant pathogen. The ferric reducing-antioxidant power and free radical 2,2-diphenyl-1-picrylhydrazyl indicated that BE had a good antioxidant activity. Peroxide value, anisidine value, conjugated diene value and protein carbonyls value indicated that BE decreased lipid and protein oxidation products in traditional yoghurt stew during storage. The antimicrobial and antioxidant effects of BE were concentration dependent and BE at 2,000 ppm was the most active. Sensory evaluation showed the addition of BE in traditional yoghurt stew was organoleptically acceptable and it can therefore be used as a natural additive in food industries. Practical Applications Concerns over the safety of some chemical antioxidant and antimicrobial additives have led to increased interest in more natural alternatives in food products. Gram-negative and gram-positive bacteria show different sensitivities against plant extracts due to differences in their cell wall compositions. Phenolic compounds could reduce the growth rate of native and contaminant bacteria. Bahar narang extract, a plant having a high phenolic content and strong antimicrobial and antioxidant properties, could be used in food products as a cheap and natural alternative for the maintenance or extension of product's shelf life. [ABSTRACT FROM AUTHOR]

Antioxidant activity, reaction mechanisms, and kinetics ofMatricaria recutitacrude extract (CE; total phenolics: 41 ± 2.5 mg/g, total flavonoids: 26 ± 1.4 mg/g, IC50: 82.3 ± 2.8 µg/mL and reducing power: 10.45 ± 0.56 mmol Fe2+/mass) in comparison totert-Butylhydroquinone during oxidation of blended vegetable oil (sunflower, soybean, and palm oil) at 120, 130, and 140°C were studied. Good correlations existed between the Rancimat oil stability index and stability indices (induction period) calculated from peroxide value, conjugated diene value, and anisidine value with no significant differences in kinetic parameters calculated from them. The temperature acceleration(Q10), activation energy (Ea), frequency factor (A), enthalpy (ΔH++), entropy (ΔS++), and free energy of activation (ΔG++) for oils containing crude extract were lower than for oils containingtert-Butylhydroquinone (0.0025, 0.005, 0.01, and 0.02%). Values were independent of crude extract ortert-Butylhydroquinone concentration. For crude extract andtert-Butylhydroquinone,EaandAwere well correlated with ΔH++and ΔS++values, respectively, but correlation betweenEaandQ10for crude extract compared totert-Butylhydroquinone was poor. Furthermore, the rate of Monounsaturated:Polyunsaturated fatty acids formation did not differ significantly between crude extract andtert-Butylhydroquinone, but concentrations of them did affect Monounsaturated:Polyunsaturated ratio. Based on the results obtained, crude extract decreased the rate of the oxidation reaction due to the decrease in the concentration of the activated complex and reduction in the rate at which the activated complex dissociated into oxidation products. [ABSTRACT FROM AUTHOR]

This work aimed to develop innovative dietary fiber‐enriched biscuits using resistant starch (RS Type III) from corn (CRS) and wheat (WRS) as wheat‐flour replacers at several ratios (0, 20, 40, 60, 80, and 100%). The effect of replacement on the physicochemical properties of dough and biscuits (moisture content, protein, amylose, resistant starch, specific volume), and their color, textural properties, microstructure, and sensory acceptability was investigated. The potential of multiple linear regression (MLR) to predict dough and biscuit properties was also assessed. Results showed that total resistant starch content was higher in biscuits containing WRS than in CRS samples, and that the chemical properties of flour had an important role in the formation of resistant starch after baking. Moisture content, protein, density, and textural characteristics reduced on increasing the resistant starch levels in both CRS and WRS samples compared with the control, while the sensory acceptability improved. Results also showed that MLR was suitable for modeling the response variables and predicting the effect of moisture and RS (before and after baking) content on texture, color, and overall liking of biscuits. Practical applications: Industries and researchers have long investigated the manufacture of dietary biscuits with low sugar content and no unfavorable aftertaste. Replacement of sugar with other sweeteners would lead to a vast effect on the sensory and structural properties of biscuits. Due to high starch content in flour, and starch hydrolysis into glucose in the human body, replacement of sugar with sugar replacers would not lead to a dietary product. Therefore, one of the suitable techniques for making biscuits with the most favorable dietary properties is the replacement of flour with resistant starch. The results of this study will be used to evaluate production methods of dietary fiber‐enriched biscuits using resistant starch. [ABSTRACT FROM AUTHOR]

The effect of ultrasound (100 W, 30 kHz, 25% amplitude for 5, 10, and 15 min; US) on growth, carbohydrate metabolism, and antioxidant activity of probiotic Lactobacillus plantarum AF1 was investigated during milk fermentation. The antioxidant activity of L. plantarum AF1 was measured by 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonate) (ABTS), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), inhibition of the autoxidation of ascorbate, reducing ability, and superoxide anion radical scavenging activity tests. The results indicated that the cell membrane permeability of sonicated samples was increased 88–94% compared to control. Additionally, β‐galactosidase activity and population of Lactobacillus strain increased with increasing ultrasound treatment time during the fermentation after the treatment. However, no significant differences were observed in the final counts of the control and the sonicated samples at the end of fermentation (24 hr). Although the lactose content was decreased significantly (p ≤ .05) by extending sonication time, the amounts of glucose, galactose, and lactic acid enhanced significantly (p ≤ .05) as the time of fermentation and sonication proceeded. The antioxidant activity was also enhanced significantly (p ≤ .05) with increase in sonication time during 24 hr fermentation after the treatment. Therefore, the lowest and the highest antioxidant activities were seen in the control sample and the US‐15 min sonicated milk at the end of fermentation, respectively. Practical applications: The dairy industry is seeking methods to increase nutritional and quality of dairy products. Recently, the ultrasound has attracted significant attention in food processing generally because of the recent consumers' trend toward functional foods. The present study provides an investigation about the efficiency of ultrasound to improve the metabolism and growth of Lactobacillus plantarum during fermentation of milk and therefore increase the quality and antioxidant activity of milk. The results show that ultrasound is a potential technique for improve metabolism of Lactobacillus strain and thus increase antioxidant activity and quality of fermented milk. Consequently, the use of ultrasound will increase the health promoting effects and quality of fermented dairy products. These results will assist in designing ultrasound procedures for optimizing the general quality of fermented milk. [ABSTRACT FROM AUTHOR]

Background: The lipase enzyme (EC: 3.1.1.3) is one of the most important catalysts in food, dairy, detergent, and textile industries., Objective: This study was performed to identify, isolate and characterize of lipase producing bacterial strain from agrifood wastes and to identify and characterize of their lipase genes., Materials and Methods: In the present study, two lipase-producing isolates were identified from the effluent of Golbahar meat products and Soveyda vegetable oil factories using in silico and in vitro approaches., Results: The results of morphological, biochemical, and molecular characterizations showed that both lipase-producing isolates belong to the Bacillus amyloliquefaciens species. Phylogenetic analysis confirmed the results of phenotypic, biochemical, and molecular characterizations. The results showed differences between LipA and LipB in the Golbahar and Soveyda isolates. Three different amino acids (residues 14, 100, and 165) were observed in LipA and one different amino acid (residue 102) was detected in LipB extracellular lipases. The protein molecular weight of the two extracted lipases ranged from 20 to 25 kDa. The identified extracellular lipases also had different physicochemical features. The maximum lipase activity of the Golbahar and Soveyda isolates was observed at 45 °C and at the pH of 8, but the Golbahar isolates exhibited higher lipase activity compared to the Soveyda isolates. The Golbahar and Soveyda isolates exhibited different activities in the presence of some ions, inhibitors, denaturing agents, and organic solvents and the Golbahar isolates showed better lipase activity than the Soveyda isolates., Conclusions: In this study, two extracellular lipase-producing isolates of B. amyloliquefaciens were identified from different food industries, and their characteristics were investigated. The results of various investigations showed that the lipases produced by the Golbahar isolate have better characteristics than the lipases of the Soveyda isolate. The Golbahar lipases have a suitable temperature and pH activity range and maintain their activity in the presence of some ions, inhibitors, denaturing agents, and organic solvents. After further investigation, the Golbahar isolate lipase can be used in various industries. In addition, this lipase can be used enzyme engineering processes and its activity can be arbitrarily changed by targeted mutations. The results of this study can increase our knowledge of extracellular lipases and may turn out to have industrial applications., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright: © 2021 The Author(s); Published by Iranian Journal of Biotechnology.)

Wheat is the most important crops worldwide, providing about one-fifth of the daily protein and calories for human consumption. The quality of cereal-based products is principally governed by the genetic basis of gluten (glutenin and gliadin proteins), which exists in a wide range of variable alleles and is controlled by clusters of genes. There are certain limitations associated with gluten characteristics, which can be genetically manipulated. The present review aimed to investigate the correlation between the genetic characteristics of gluten protein components and wheat-based product's quality. According to various references, Glu-B1d (6 + 8) , Glu-B1h (14 + 15) and Glu-B1b (7 + 8) are related to higher gluten strength and pasta quality, while, subunits Dx2 + Dy12 and Dx5 + Dy10, are usually present at the Glu-D1 locus in bread wheat, resulted in lower cooked firmness in pasta. Moreover, introducing Gli-D1/Glu-D3 and Glu-D1 loci into durum wheat genomes, causing to provide the maximum values of gluten index in pasta products. 1Dx5 + 1Dy10 alleles determine the level of increase in dough's consistency, elasticity, viscosity, and extensibility quality of baking and appropriate bread loaf volume, while 1Dx2 + 1Dy12 as the alleles associated with poor baking quality, being more suitable for soft wheat/pastry end uses. Bx7, Bx7 OE , 1Bx17 + 1By18, 1Bx13 + 1By16, Bx7 + By9 and 1Bx7 + 1By8 at Glu-B1 alleles and 1Ax2* found on Glu-A1, augmented dough strength and has positive effects on consistency, extensibility, viscosity, and elasticity of bread dough. Breeding programs by genome editing have made gluten a promoting component for improving cereal-based products., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

In the present research, the impact of fermentation with two strains of Lactiplantibacillus plantarum subsp. plantarum (PTCC 1896 and PTCC 1745) on physicochemical properties, antioxidant bioactive compounds, and some health-promoting features of guava juice was investigated. Results showed a significant ( p <  .05) decrease in pH, total soluble solids, glucose and fructose residues, vitamin C, and total carotenoids after 32 h of fermentation. Total phenolic content, free radical scavenging abilities, and ferrous reducing power were markedly enhanced during the fermentation process. Moreover, fermented juice represented good enzyme inhibition abilities (α-amylase and α-glucosidase) and anti-inflammatory activities. The initial amount of angiotensin-converting enzyme inhibitory activity (26.5%) increased to 72.1% and 66.4% in L. plantarum subsp. plantarum 1896 and L. plantarum subsp. plantarum 1745 treatments, respectively. These findings reveal that guava juice fermentation with the studied Lactobacillus strains can be a promising strategy to augment the functional properties of the fruit-based beverage., Competing Interests: The authors declare that they have no conflict of interest., (© 2023 The Authors. Food Science & Nutrition published by Wiley Periodicals LLC.)

The high water and nutritional contents of meat and fish products make them susceptible to spoilage. Thus, one of the most important challenges faced by the meat industry is extending the shelf life of meat and fish products. In recent years, increasing concerns associated with synthetic compounds on health have limited their application in food formulations. Thus, there is a great need for natural bioactive compounds. Direct use of these compounds in the food industry has faced different obstacles due to their hydrophobic nature, high volatility, and sensitivity to processing and environmental conditions. Nanotechnology is a promising method for overcoming these challenges. Thus, this article aims to review the recent knowledge about the effect of biopolymer-based edible films or coatings on the shelf life of meat and fish products. This study begins by discussing the effect of biopolymer (pectin, alginate, and chitosan) based edible films or coatings on the oxidation stability and microbial growth of meat products. This is followed by an overview of the nano-encapsulation systems (nano-emulsions and nanoliposomes) and the effect of edible films or coatings incorporated with nanosystems on the shelf life of meat and fish products.

This study examined the effect of beef fermentation with Lactiplantibacillus paraplantarum ( L ) PTCC 1965, Lactiplantibacillus ( L ) plantarum subsp. plantarum PTCC 1745, and Lactiplantibacillus ( L ) pentosus PTCC 1872 bacteria on the growth of pathogenic bacteria, including Salmonella (S) Typhi PTCC 1609 and Staphylococcus ( S ) aureus PTCC 1826. The growth of lactic acid bacteria (LAB) and the effect of fermentation on pathogenic bacteria were studied using Weibull: biphasic linear and competitive models. The results showed that the rate of pH reduction was lower in the early stages and increased as the microbial population grew. The α parameter was lower for L. plantarum subsp. plantarum compared to L. paraplantarum and L. pentosus . The comparison of the α parameter for bacterial growth and pH data showed that the time interval required to initiate the rapid growth phase of the bacteria was much shorter than that for the rapid pH reduction phase. The pH value had a 50% greater effect on the inactivation of S. Typhi when compared to the samples containing L. plantarum subsp. plantarum and L. pentosus . The same parameter was reported to be 72% for the inactivation of St. aureus . In general, during the fermentation process, LAB strains caused a decrease in pH, and as a result, reduced the growth of pathogens, which improves consumer health and increases the food safety of fermented meat.

Lactic acid is an organic compound produced via fermentation by different microorganisms that are able to use different carbohydrate sources. Lactic acid bacteria are the main bacteria used to produce lactic acid and among these, Lactobacillus spp. have been showing interesting fermentation capacities. The use of Bacillus spp. revealed good possibilities to reduce the fermentative costs. Interestingly, lactic acid high productivity was achieved by Corynebacterium glutamicum and E. coli, mainly after engineering genetic modification. Fungi, like Rhizopus spp. can metabolize different renewable carbon resources, with advantageously amylolytic properties to produce lactic acid. Additionally, yeasts can tolerate environmental restrictions (for example acidic conditions), being the wild-type low lactic acid producers that have been improved by genetic manipulation. Microalgae and cyanobacteria, as photosynthetic microorganisms can be an alternative lactic acid producer without carbohydrate feed costs. For lactic acid production, it is necessary to have substrates in the fermentation medium. Different carbohydrate sources can be used, from plant waste as molasses, starchy, lignocellulosic materials as agricultural and forestry residues. Dairy waste also can be used by the addition of supplementary components with a nitrogen source., (© 2020 The Author(s).)

This study investigated the effect of different levels (4, 8 and 12%) of sucrose, isomalt and maltodextrin on the microstructural, water absorption, physico-chemical, thermal and textural characteristics of wheat and cassava starch gels, by scanning electron microscopy (SEM), rapid visco analysis (RVA), differential scanning calorimetry (DSC) and texture profile analysis. According to SEM analysis, cassava granules were more impressed than wheat starch in the presence of isomalt > sucrose > maltodextrin. Results showed that water absorption decreased when the amount of sucrose, isomalt and maltodextrin increased. In contrast, onset (T o ), peak (T p ) and conclusion (T c ) temperature, and enthalpy (ΔH) of wheat and cassava starch gels, increased as the level of addition increased. With increasing the sugar concentration, T o , T p , T c and ΔH gel enhanced significantly relative to the native starch. The polyols had more remarkable effects on the thermal properties of cassava starch than wheat starch. The texture of wheat and cassava starch gels incorporated with polyol sugars had solid-like properties. The gelatinization of starch was delayed more by isomalt than sucrose and maltodextrin. Moreover, the combination of principal component analysis and cluster analysis proved to be a suitable statistical approach to highlight the effect of adding varying levels of polyols to starch., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The oxidative stability, as well as the chemical composition of Amygdalus reuteri kernel oil (ARKO), were evaluated and compared to those of Amygdalus scoparia kernel oil (ASKO) and extra virgin olive oil (EVOO) during and after holding in the oven (170 °C for 8 h). The oxidative stability analysis was carried out by measuring the changes in conjugated dienes, carbonyl and acid values as well as oil/oxidative stability index and their correlation with the antioxidant compounds (tocopherol, polyphenols, and sterol compounds). The oleic acid was determined as the predominant fatty acid of ARKO (65.5%). Calculated oxidizability value and an iodine value of ARKO, ASKO and EVOO were reported as 3.29 and 3.24, 2.00 and 100.0, 101.4 and 81.9, respectively. Due to the high wax content (4.5% and 3.3%, respectively), the saponification number of ARKO and ASKO (96.4 and 99.8, respectively) was lower than that of EVOO (169.7). ARKO had the highest oxidative stability, followed by ASKO and EVOO. Therefore, ARKO can be introduced as a new source of edible oil with high oxidative stability., (Copyright © 2018. Published by Elsevier Ltd.)

The aim of this work was to investigate the effect of various microwave heating times (1, 3, 5, 10, and 15min) on the chemical properties of novel edible oil sources, including Mashhadi melon (Cucumis melo var. Iranians cv. Mashhadi), Iranian watermelon (Citrullus lanatus cv. Fire Fon), pumpkin (Cucurbita pepo subsp. pepo var. Styriaca), and yellow apple (Malus domestica cv. Golden Delicious) seed oils. The evaluated parameters were peroxide value (PV), conjugated diene (CD) and triene (CT) values, carbonyl value (CV), p-anisidine value (AnV), oil stability index (OSI), radical scavenging activity (RSA), total tocopherols, total phenolics, as well as chlorophyll and carotenoid contents. Results showed that extended microwave heating involves decreased quality of the seed oils, mainly due to the formation of primary and secondary oxidation products. Microwave heating time also affects the total contents of chlorophylls, carotenoids, phenolics and tocopherols, which clearly decrease by increasing the exposure time. The order of oxidative stability of the analyzed edible oils was pumpkin>Mashhadi melon>Iranian watermelon>yellow apple. The obtained results demonstrated the promising potential of these novel edible oils for different food applications., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In this study, in order to introduce natural antioxidative vegetable oil in food industry, the kolkhoung hull oil and kernel oil were extracted. To evaluate their antioxidant efficiency, gas chromatography analysis of the composition of kolkhoung hull and kernel oil fatty acids and high-performance liquid chromatography analysis of tocopherols were done. Also, the oxidative stability of the oil was considered based on the peroxide value and anisidine value during heating at 100, 110 and 120 °C. Gas chromatography analysis showed that oleic acid was the major fatty acid of both types of oil (hull and kernel) and based on a low content of saturated fatty acids, high content of monounsaturated fatty acids, and the ratio of ω-6 and ω-3 polyunsaturated fatty acids, they were nutritionally well--balanced. Moreover, both hull and kernel oil showed high oxidative stability during heating, which can be attributed to high content of tocotrienols. Based on the results, kolkhoung hull oil acted slightly better than its kernel oil. However, both of them can be added to oxidation-sensitive oils to improve their shelf life.