The Effects of Different Roasting Methods on the Phenolic Contents, Antioxidant Potential, and In Vitro Inhibitory Activities of Sacha Inchi Seeds

Roasted sacha inchi seeds are now commercialized as a health food product, but the influence of roasting methods on their proclaimed health effects has yet to be explored. This study investigated the total phenolic contents (TPCs), antioxidant potential, and inhibitory activities of raw and roasted sacha inchi seeds in vitro. Individual phenolics in raw seeds were also identified in an attempt to explain the bioactivities of the seeds. The results suggested that roasting in a cooking pan, vacuum oven, and tray dryer had distinct impact on TPC in sacha inchi seeds, and thus differentially altered their antioxidant and inhibitory properties. Seeds that underwent roasting exhibited 1.5-2.7-fold higher antioxidant potentials than raw seeds. Certain roasting methods provided the products with anti-alpha-amylase and anti-cholinesterase activities, while inhibitions of these enzymes were not detected in raw seeds. Roasted seeds also possessed superior anti-lipase and anti-glycation activities when compared with raw seeds (up to 1.7- and 4.8-fold, respectively). The inhibitory properties observed in the seed samples might be attributed to their p-coumaric acid, ferulic acid, and quercetin, as these potential enzyme inhibitors were predominant in raw seeds. The overall results showed that pan-roasting could be used to obtain relatively high health benefits from the antioxidant and inhibitory activities of sacha inchi seeds. The information obtained from this study may serve as the basis for the proper processing of sacha inchi seeds to optimize their functional food and nutraceutical applications.