Effect of drying temperature on physicochemical properties and resistant starch in unripe banana flour obtained from Kluai Khai Pratabong (Musa acuminata, AAA Group) and its application in a soup product

Abstract

Bananas are one of the lowest cost fruits, mostly grown in tropical/subtropical countries. They are a significant source of nutrients that aid in digestion, weight loss, and heart health. Unripe banana flour (UBF) is a complex carbohydrate source, with a high resistant starch (RS) content, and can be used as a functional ingredient. This study evaluated the effects of drying temperature (40, 50, or 60 C) on RS content and physicochemical properties of UBF from Kluai Khai Pratabong. Application of UBF as a thickener in soup products was also assessed. The highest RS contents were found in flour samples dried at 40 ˚C or 50 ˚C (41% RS). Nonetheless, a minor difference in physicochemical properties of UBF was observed when it was dried at different temperatures. The optimization of the soup formula based on viscosity, RS content, and overall liking scores revealed that the optimum amounts of chicken broth (CB), boiled Nile tilapia (NF), and UBF in the soup product were 85.06 %, 9.97 %, and 4.97 %, respectively. Increasing the amount of UBF in soup products resulted in increased RS and fiber contents. As such, Kluai Khai Pratabong flour can be employed as a functional ingredient in health food products.

Keywords

• resistant starch
• unripe banana flour
• physicochemical properties
• kluai khai pratabong
• soup product