[4-1330-C] Functional/Wellness Foods & Nutrition (1)

[4-1330-C-04] Utilization of Banana Agricultural Waste: Effects of Processing Conditions on Properties of Unripe Banana (Musa Cavendish) Pulp and Peel Flours

*Natthawuddhi Donlao^1,2, Asia Perin¹, Nasuha Bunyameen¹ (1. School of Agro-Industry, Mae Fah Luang University, Chiang Rai, Thailand(Thailand), 2. Innovative Food Packaging and Biomaterials Unit (IFP), Mae Fah Luang University, Thailand(Thailand))

Keywords:Antioxidant capacity, Banana peel flour, Banana pulp flour, Citric acid, Drying temperature, Resistant starch

Banana is one of the most important tropical fruits. Flour from green bananas contains a high amount of resistant starch that can reduce constipation, prevent colon cancer and provide benefit to the digestive system. Banana peel is an underused by-product which is known as a potential source of high dietary fiber, protein, essential amino acids, and total phenolic compounds. The objective of this study was to investigate the effects of citric acid pretreatments and drying temperatures on physical, chemical, and functional properties of unripe banana pulp and peel flours. Rejected green bananas (Musa cavendish) at the 2^nd stage of maturity were obtained from Phaya Meng Rai Agricultural Limited Partnership in Phaya Meng Rai District, Chiang Rai, Thailand. Unripe bananas were washed with clean water and drained. Banana pulps and peels were then separated. The banana pulps and peels were pretreated with citric acid solution at different concentrations (i.e., 0.5, 0.7, and 1.0% w/v) and dried at different temperatures (i.e., 40, 60, and 80 °C). Moisture content, color, water holding capacity, and pasting properties of two flours were determined. Resistant starch of banana pulp flour and total polyphenol content and antioxidant activity of banana peel flour were also determined. In banana pulp flour, higher citric acid concentration and drying temperature resulted in a lower level of moisture content and water holding capacity. The resistant starch increased with increasing drying temperature. Highest peak viscosity was found at the condition of 0.7% citric acid pretreatment. In banana peel flours, total polyphenol content increased with increasing drying temperature. A higher concentration of the citric acid solution and lower drying temperature resulted in increasing L* value. The highest value of antioxidant capacity was found in the sample dried at 60 °C. It is recommended that pretreating with 1.0% citric acid solution and drying at 80 °C can produce good quality of banana pulp flour. However, good quality of banana peel flour can be achieved by pretreating with 1.0% citric acid solution, followed by drying at 60 °C.