Apple Tepache fermented with tibicos: Changes in chemical profiles, antioxidant activity and inhibition of digestive enzymes

Abstract

The effect of adding tibicos in traditional beverage (Tepache) made from apple nectar fermentation on microbial populations, phenolic profile, antioxidant activities, and inhibition of digestive enzymes was evaluated. Apple nectar was obtained from fresh apples and fermented at 25°C for 168 hr without initiator inoculum (Te/s) and with tibicos as initiator inoculum (Te/ti). The obtained results of bacterial growth indicate 120 hr to growth without inoculum (tibicos), in comparison with 96 hr in fermentations added with tibicos. The addition of tibicos impacted on the phenolic profile of the beverage, during the fermentation process. In general, levels of protocatechuic acid, chlorogenic acid, 4-O-caffeoylquinic acid, catechin, epicatechin, quercetin 3-O-glucoside, kaempferol 3-O-glucoside, and phlorizin were the predominant phenolic compounds in the beverage. Principal component analysis demonstrated that quercetin 3-O-glucoside, quercetin, taxifolin, and phlorizin have the highest reducing power and are closely related to the ability to inhibit α-glucosidase, while the epicatechin and chlorogenic acid levels are related to the highest response on oxygen radical absorbance capacity. Novelty impact statement The use of tibicos to obtain a traditional fermented beverage (Tepache) from apple nectar showed increased level of quercetin 3-O-glucose, quercetin, taxifolin, and phlorizin; in comparison with spontaneous fermented beverages, these phenolic compounds have highest reducing power. Also, epicatechin and chlorogenic acids show higher values in Tepache obtained with starter cultures, and they were related to the high oxygen radical absorbance capacity. On the other hand, important increase in catechin, eriodyctiol, naringenin, and 4-hydroxybenzoic acid related with tibicos fermentation showed a positive relationship with free radical scavenging activity.