The effect of roasting conditions on some physicochemical characteristics of coffee beans as color, browning index, hydroxymethylfurfural (HMF), caffeine, phenolic acids, and antioxidant capacity were investigated. The thermostability of chlorogenic acid and caffeine was investigated using Arrhenius equation. Furthermore, principal component analysis (PCA) was applied to reveal the relationship between the phenolic profiles, browning index, and the antioxidant capacity of coffee. Chlorogenic acid was the main phenolic compounds in coffee beans. It gradually decreased from 34.181 to 2.584 mg/g of sample during roasting at 220 C for 40 min. Gallic acid, caffeic acid and HMF increased at the beginning of roasting time and decreased afterward. The antioxidant capacity of green coffee showed the highest antioxidant capacity. Two principal components, (PC1 and PC2) with eigenvalues 5.89 and 2.5 respectively, which demonstrated 93.35% of the total variance in the data set. Therefore, the paramount way to reserve a good level of phenolic compounds in parallel with a good taste is the roasting of coffee at 180 C for 20 min or 220 C at 10 min.

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This study was designed to prepare and evaluate low-phenylalanine toast bread made from gliadin-free wheat flour and hydrocolloids. Wheat protein fraction (gliadin) rich in phenylalanine was extracted using aqueous alcohol solution for the production of low-phenylalanine wheat flour. Pectin, gum arabic and carboxymethylcellulose (CMC) were used separately to improve the quality of bread at levels of 1, 2 and 3%. Chemical, rheological, organoleptic, baking, staling and microstructure of bread were studied. Phenylalanine content of gliadin-free bread samples reduced by 43.2% compared with control. Separation of gliadin negatively affected the rheological properties of dough and baking quality of bread, while rheological properties, baking quality and staling were improved upon hydrocolloids addition. Microscopic examination of crumb structure revealed remarkable differences in control and treated breads. It was found that acceptable bread could be produced using gliadin-free wheat flour with the addition of pectin or CMC up to 2 and 3%, respectively.

Metabolic syndrome (MetS) is characterized as a gathering of various metabolic disorders, for example, hyperglycemia, dyslipidemia, and obesity. The present research was conducted to prepare fortified almond milk as functional beverages and evaluate their protective effect against MetS and associated hepatic and vascular complications. Three beverages (I, II, and III) were prepared by fortification almond milk with carrot juice or powder of quinoa seeds and carrot juice or oat powder and banana juice. The sensory attributes, physicochemical properties, bioactive compounds (total phenolic, beta-carotene, tocopherols) and B-complex vitamins were determined in the beverages. In-vitro antioxidant activity of the beverages was assessed. MetS was induced in rats via feeding on high-fat high-fructose diet (HFHF). The biochemical (lipid profile, oxidative stress, liver, and kidney functions), nutritional and histopathological parameters were assessed in rats. The beverage I recorded the highest sensory attributes' scores. The physicochemical properties of the beverages revealed that acidity and viscosity of all beverages ranged from 4.55 to 4.88 and from 40 to 59, respectively. The beverage I showed the highest content of alpha-tocopherol (14.994 μg/g) and beta-carotene (104.541 μg/g), while the beverage II showed the highest content of gamma-tocopherol (0.557 μg/g), folic acid (0.806 μg/g), and total phenols (147.43 μg GAE/g). The results of animals revealed that the beverage II was the most promising in attenuation levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, malondialdehyde, and tumor necrosis factor-alpha. Also, the beverage II was the superior in the protection of the liver and heart tissues as reflected by the histopathological examination findings. So, it can be concluded that the newly prepared almond milk with quinoa seeds and carrot juice could be used as an effective functional beverage for the prevention of MetS and its complications.

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