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Oxidation of fats in food greatly reduces their shelf life and causes food of unacceptable quality to be presented to the customer. In this regard, this research was conducted with the aim of increasing the oxidative stability of sesame oil with nanoliposomes containing the antioxidant extract of yarrow plant. In this study, 6 concentrations of nanoliposomes containing yarrow plant extract (0, 50, 100, 200, 500 and 1000 ppm) were used in sesame oil, and tests such as acidity, peroxide, thiobarbituric acid index, conjugate diene were performed on those oils. And after finding the best concentration of nanoliposome containing yarrow extract, this sample was compared with the sample containing the same amount of free yarrow extract and also the sample with 200 ppm BHT after 7 days of storage at 63 degrees Celsius. The results showed that with increasing storage time, acidity level, thiobarbituric acid index and conjugate diene increased, but with the increase of nanoliposome containing 500 ppm of yarrow extract, these characteristics decreased and then increased. Unlike other characteristics, the peroxide content of the samples decreased from the 5th day onwards. On the other hand, it was found that the sample containing 500 ppm of free yarrow extract had the highest level of acidity, peroxide, thiobarbituric acid index and conjugate diene. The highest oxidative stability (14.21 hours) belonged to the oil with nanoliposome containing 500 ppm of yarrow extract. The dominant fatty acid in sesame oil containing nanoliposome as well as control was linoleic acid, and the use of antioxidants did not significantly change the fatty acid profile of sesame oil. Finally, it can be stated that the use of nanoliposome containing yarrow plant extract is a suitable alternative for synthetic antioxidants available in the market [ABSTRACT FROM AUTHOR]

Gamma-amino butyric acid (GABA) as a non-protein amino acid has a widespread application in the body's various organs and inhibition of many physiologic diseases. Lactic acid bacteria are able to GABA synthesis in many foods. The purpose of this study was to ferment the soymilk by a new lactic acid bacterium called Lactobacillus sp. Makhdzir Naser-1 (GQ451633). At first, optimum conditions for maximum GABA production were obtained with regard to effective factors such as inoculation time, pH, soy milk concentration and ambient temperature. The optimum conditions are: fermentation time 48 hours, pH 5.3, 12% soy milk and warming temperature 37 ° C. At optimum point, with three repeats of treatment, the produced GABA was 4.17, which has not very significant difference with the predicted value (4.188). Therefore, the accuracy of the proposed equation for predicting GABA value was confirmed. [ABSTRACT FROM AUTHOR]

Regarding the antioxidant properties of Adiantum capillus-veneris, identification of phytochemical compounds, extraction of phenolic compounds, and determination of inhibitory activity of free radicals of this plant seem necessary. Therefore, in this study, the structure of fatty acids, tocopherols, sterols, and phenols was identified. Then, the effect of methanol and ethanol solvents on extraction of polyphenolic compounds and antioxidant activity of Adiantum capillus-veneris leaf extract were investigated. The results of identification of the chemical compounds of the extract showed that palmitic acid was the predominant saturated fatty acid, gamma and beta tocopherols were the most abundant tocopherols, cytosterol the most abundant sterol, and syringic acid and hydroxytyrosol the main phenol of the leaf extract. Measurement of phenolic compounds showed that by increasing the concentration of extract up to 1000 ppm, the amount of polyphenolic extracted in methanol and ethanol solvents increased to 240.65 and 142.4 mg GA/g, respectively, but the extraction percentage of these antioxidants by methanol was significantly higher than ethanol. In the next step, the inhibitory activity of free radicals was measured at different concentrations of methanol and ethanol and compared with the synthetic antioxidant BHT at 200 ppm; it was found that increasing the antioxidant properties of methanolic and ethanolic extracts depend on concentration, meaning that by increasing the concentration of extracts from 200 ppm to 1000 ppm, the antioxidant activity increased significantly and at a constant concentration, the methanol-extracted extract had more radical scavenging activity than the ethanol-extracted extract and both extracts had more antioxidant activity than synthetic antioxidant BHT. Generally, the results of this study showed that methanol is a more effective solvent in extraction of phenolic compounds from Adiantum capillus-veneris leaves. There was also a positive correlation between the amount of phenols and antioxidant activity. [ABSTRACT FROM AUTHOR]

Millets are gaining attention due to their many advantages in cultivation and overall nutritional benefits. Research has been carried out to explore the nutritional properties of various millets. However, the use of millets in today’s food processing is minimal as compared to wheat. Three minor millets, namely foxtail, proso, and pearl millets grown in Iran were used in this study. The water absorption characteristics and hardness of these millets have been investigated. The effect that millet flours incorporated in dough have on its rheology has been studied and compared with the effect of wheat on dough rheology. The moisture content of millets increased with an increase in the water temperature, and a regular increase in the water absorption capacity, too, was observed as the temperature rose. The hardness of the millet decreased with an increase in the moisture content of the grains. Pearl millet has been found to have the lowest hardness irrespective of the steeping time and temperature. Incorporation of millet in the dough adversely affected the dough rheology in terms of workability and baking quality. Proso millet highly negatively affected the dough rheology in terms of dough hardness, stability, and dynamic rheological properties. This research highlights the possibility to predict the water absorption characteristics of millet grains to be used to optimise the conditions under which millets are steeped in various bioprocessing operations. It is supposed that on performing proper baking trials to compare the properties of composite flours made from these millets, the results of the rheological studies will prove beneficial and the rheological properties and behaviour will be accurately correlated when the food is applied practically. [ABSTRACT FROM AUTHOR]