Improving Phenolic Bioactive-Linked Functional Qualities of Sweet Potatoes Using Beneficial Lactic Acid Bacteria-Based Biotransformation Strategy

Development of low-fat and anthocyanin-rich purple sweet potato vacuum fried chips

Vacuum frying technology has proven to be one of the best methods to produce snack products with higher retention of health-promoting/protecting nutraceuticals with reduced-fat content. In this work, application and optimization of vacuum frying process for purple sweet potato have used response surface methodology-based Box-Behnken design to produce low-fat and anthocyanin-rich purple sweet potato vacuum fried chips. The study showed the significant impact of frying temperature, vacuum pressure, and frying time on the chip's moisture and oil content, level of anthocyanin, visual impressions like color and texture. The selection of optimized frying parameters was carried out using a numerical optimizer and found to be 105°C for 7.08 min at a reduced pressure of 14.79 kPa. Compared to the atmospheric deep-fried chips, the vacuum fried chips showed 86% retention of anthocyanin content and a 35.6% decline in oil content with a lower breaking force of 0.69 N. Overall, the study confirmed that vacuum fried purple sweet potato chips could be a viable option to produce snacks with high functional value to meet the current consumer demands. PRACTICAL APPLICATION: Purple sweet potatoes have the potential to produce healthy snack chips with lower fat content and higher functional characteristics when vacuum frying technology is used with optimized processing variables.

Sweet Potato (Ipomoea batatas L.) Phenotypes: From Agroindustry to Health Effects

Sweet potato (SP; Ipomoea batatas (L.) Lam) is an edible tuber native to America and the sixth most important food crop worldwide. China leads its production in a global market of USD 45 trillion. SP domesticated varieties differ in specific phenotypic/genotypic traits, yet all of them are rich in sugars, slow digestible/resistant starch, vitamins, minerals, bioactive proteins and lipids, carotenoids, polyphenols, ascorbic acid, alkaloids, coumarins, and saponins, in a genotype-dependent manner. Individually or synergistically, SP’s phytochemicals help to prevent many illnesses, including certain types of cancers and cardiovascular disorders. These and other topics, including the production and market diversification of raw SP and its products, and SP’s starch as a functional ingredient, are briefly discussed in this review.

Phenolic Bioactives From Plant-Based Foods for Glycemic Control

Plant-based foods containing phenolic bioactives have human health protective functions relevant for combating diet and lifestyle-influenced chronic diseases, including type 2 diabetes (T2D). The molecular structural features of dietary phenolic bioactives allow antioxidant functions relevant for countering chronic oxidative stress-induced metabolic breakdown commonly associated with T2D. In addition to antioxidant properties, phenolic bioactives of diverse plant foods have therapeutic functional activities such as improving insulin sensitivity, reducing hepatic glucose output, inhibiting activity of key carbohydrate digestive enzymes, and modulating absorption of glucose in the bloodstream, thereby subsequently improving post-prandial glycemic control. These therapeutic functional properties have direct implications and benefits in the dietary management of T2D. Therefore, plant-based foods that are rich in phenolic bioactives are excellent dietary sources of therapeutic targets to improve overall glycemic control by managing chronic hyperglycemia and chronic oxidative stress, which are major contributing factors to T2D pathogenesis. However, in studies with diverse array of plant-based foods, concentration and composition of phenolic bioactives and their glycemic control relevant bioactivity can vary widely between different plant species, plant parts, and among different varieties/genotypes due to the different environmental and growing conditions, post-harvest storage, and food processing steps. This has allowed advances in innovative strategies to screen and optimize whole and processed plant derived foods and their ingredients based on their phenolic bioactive linked antioxidant and anti-hyperglycemic properties for their effective integration into T2D focused dietary solutions. In this review, different pre-harvest and post-harvest strategies and factors that influence phenolic bioactive-linked antioxidant and anti-hyperglycemic properties in diverse plant derived foods and derivation of extracts with therapeutic potential are highlighted and discussed. Additionally, novel bioprocessing strategies to enhance bioavailability and bioactivity of phenolics in plant-derived foods targeting optimum glycemic control and associated T2D therapeutic benefits are also advanced.