The effect of kappa-carrageenan and gum Arabic on the production of guava-banana fruit leather.

Guava-banana fruit leather was made by heat-drying a mixture of guava puree, banana puree, sorbitol, kappa-carrageenan or gum Arabic, and water at 60 °C for 8 h in various formulations (F1 to F6). Each formulation was evaluated for its effect on water activity, texture, surface color, proximate composition, pH, ascorbic acid content, antioxidant activity, and sensory properties. Hydrocolloid kappa-carrageenan was found to be the most significant independent variable affecting the desired properties. However, using gum Arabic was more effective at maintaining both water activity and ascorbic acid levels, as well as improving starch digestibility in vitro. In general, there was no discernible effect of the guava to banana ratio in any formulation. While hydrocolloids have no effect on the texture of guava-banana fruit leather, they do affect other sensory characteristics such as color, aroma, taste, and overall. In general, panelists preferred fruit leather made with a 50:50 (F1), 40:60 (F3), or 30:70 (F6) guava-banana ratio and containing kappa-carrageenan.

Protective Effects of Anthocyanin Extract from Purple Sweet Potato (Ipomoea batatas L.) on Blood MDA Levels, Liver and Renal Activity, and Blood Pressure of Hyperglycemic Rats.

There has been a dynamic progression in the study of purple sweet potatoes, particularly in regard to their antioxidant compounds, such as anthocyanins. Antioxidants can reduce oxidative stress due to hyperglycemia, therefore research into the protective effects of hyperglycemia is essential. This study was conducted to investigate the protective effects of anthocyanin extracts from purple sweet potatoes on blood malondialdehyde (MDA) levels, liver and renal activity, and blood pressure in hyperglycemic rats. Anthocyanin from purple sweet potato (APSP) was extracted with ethanol-citric acid 3% solvent. Twenty-four rats were split into four experimental groups: (i) healthy rats; (ii) hyperglycemic rats without anthocyanin treatment; (iii) hyperglycemic rats treated with APSP extract at a dose of 50 mg/kg; and (iv) hyperglycemic rats treated with APSP extract at a dose of 100 mg/kg. Rats received treatment for 35 days. The results showed that consumption of APSP significantly reduced levels of MDA in the blood, and liver and renal systems. APSP could reduce the urea and creatinine levels, which are indicative of improved renal function. In addition, APSP could decrease serum glutamate oxalacetate transaminase and serum glutamate pyruvate transaminase levels, indicative of protective activity of the extract on liver, and decrease systolic blood pressure. Accordingly, it was concluded that APSP could be developed as a functional food for treatment of diabetes.