Glycemic potential of Philippine grains during co-digestion with bignay[Antidesma bunius (L.) Spreng] pomace: an in vitro study

There has been increased demand for functional foods nowadays as people move towards a healthier lifestyle. Underutilized fruits, such as bignay [Antidesma bunius (L.) Spreng], are currently being investigated because of their high amounts of bioactive substances with health-promoting effects, particularly in addressing non-communicable diseases such as obesity and diabetes mellitus. Hence, this study evaluated the effect of bignay pomace on the estimated glycemic index (eGI) when co-digested with locally consumed grains. Results showed that upon addition of 1% freeze-dried bignay pomace, significant reductions in the estimated glycemic index [eGI] (7–17%) and hydrolysis index (15–32%) occurred during the two-stage simulated in vitro digestion of rice, adlai, white corn grits (WCG), 50:50 rice: adlai mix, and 70:30 rice: WCG mix. Further analysis revealed that the total dietary fiber and resistant starch contents in the grains affected the eGI of the grains, such that the amounts present retarded the rate of starch digestion. Bignay pomace significantly lowered the rate of the in vitro digestion of local grains, suggesting its potential to improve glycemic index. The study serves as relevant baseline data for the possible valorization of bignay pomace as a food supplement for the prevention of noncommunicable diseases.