Various phenolic and flavonoid compounds that are secondary plant metabolites are known to contribute to physiological wellbeing. Extraction efficiency of such compounds from plant sources is dependent on the extracti...Various phenolic and flavonoid compounds that are secondary plant metabolites are known to contribute to physiological wellbeing. Extraction efficiency of such compounds from plant sources is dependent on the extraction solvent type and composition, and its pH. In this study, different extraction variables were examined: heating time (20 to 180 min), temperature (60°C, 75°C and 90°C) and pH (2.5, 3.0, 4.0, 5.0, 6.0 and 7.0). Hot water was used in the extraction of dry samples. For phenolics, the most efficient extraction was by using water at 60°C for 180 min, whereby 5.95 mg GA equivalent/dry extract was achieved. The most efficient extraction of flavonoids was achieved with water at 60°C for 150 min, whereby 43 μg Quercetin equivalent/dry extract was obtained. Adjusting the solvent to pH 2.5 increased the yield to 45.3 μg Quercetin equivalent/dry extract.展开更多
Fox nut (Euryale ferox) is categorized among superior quality foods because of its highly nutritious profile. It also serves as a good protein source for vegetarian diets. However, it is not widely consumed, due to so...Fox nut (Euryale ferox) is categorized among superior quality foods because of its highly nutritious profile. It also serves as a good protein source for vegetarian diets. However, it is not widely consumed, due to soggy texture and bland flavor as compared to other nuts. In this study, we used roasting and seasoning to enhance its consumer acceptance. Furthermore, we have also compared biochemical, nutritional and physical properties of the roasted and unroasted fox nuts;and their Glycemic Index (GI) in human subjects. Results showed that roasting significantly (P ≤ 0.05) improved the minerals content (from 0.58 to 0.66%), protein content (from 11.40 to 14.57%), total phenolics (from 346.02 to 470.62 mg GAE/100 g), flavonoids (from 4.15 to 4.43 mg CE/g), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (from 48.54 to 79.13% inhibition) and Ferric Reducing Antioxidant Power (from 662.46 to 957.14 μmol FeSO4/g). Consumer acceptance was evaluated with and without seasoning;both salt and spice seasoned roasted nuts had greater overall acceptability as compared to plain roasted and unroasted nuts. Fox nuts also reported low GI (37%) in human subjects (ethical approval #1772/01-06-2020). Thus, roasted fox nuts can be consumed as nutrient rich and low GI snack;not only as a component of healthy diet but can also be served to patients with metabolic disorders like obesity and diabetes.展开更多
文摘Various phenolic and flavonoid compounds that are secondary plant metabolites are known to contribute to physiological wellbeing. Extraction efficiency of such compounds from plant sources is dependent on the extraction solvent type and composition, and its pH. In this study, different extraction variables were examined: heating time (20 to 180 min), temperature (60°C, 75°C and 90°C) and pH (2.5, 3.0, 4.0, 5.0, 6.0 and 7.0). Hot water was used in the extraction of dry samples. For phenolics, the most efficient extraction was by using water at 60°C for 180 min, whereby 5.95 mg GA equivalent/dry extract was achieved. The most efficient extraction of flavonoids was achieved with water at 60°C for 150 min, whereby 43 μg Quercetin equivalent/dry extract was obtained. Adjusting the solvent to pH 2.5 increased the yield to 45.3 μg Quercetin equivalent/dry extract.
文摘Fox nut (Euryale ferox) is categorized among superior quality foods because of its highly nutritious profile. It also serves as a good protein source for vegetarian diets. However, it is not widely consumed, due to soggy texture and bland flavor as compared to other nuts. In this study, we used roasting and seasoning to enhance its consumer acceptance. Furthermore, we have also compared biochemical, nutritional and physical properties of the roasted and unroasted fox nuts;and their Glycemic Index (GI) in human subjects. Results showed that roasting significantly (P ≤ 0.05) improved the minerals content (from 0.58 to 0.66%), protein content (from 11.40 to 14.57%), total phenolics (from 346.02 to 470.62 mg GAE/100 g), flavonoids (from 4.15 to 4.43 mg CE/g), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (from 48.54 to 79.13% inhibition) and Ferric Reducing Antioxidant Power (from 662.46 to 957.14 μmol FeSO4/g). Consumer acceptance was evaluated with and without seasoning;both salt and spice seasoned roasted nuts had greater overall acceptability as compared to plain roasted and unroasted nuts. Fox nuts also reported low GI (37%) in human subjects (ethical approval #1772/01-06-2020). Thus, roasted fox nuts can be consumed as nutrient rich and low GI snack;not only as a component of healthy diet but can also be served to patients with metabolic disorders like obesity and diabetes.
