This Is AuburnElectronic Theses and Dissertations

Physicochemical and Nutritional Properties of Selected Banana (Musa spp.) Cultivated in Southeastern U.S.

Date

2019-08-03

Author

Kargar, Mahnaz

Type of Degree

PhD Dissertation

Department

Horticulture

Restriction Status

EMBARGOED

Restriction Type

Full

Date Available

08-01-2024

Abstract

Globally, banana (Musa spp.) is considered a daily dietary staple food for millions of individuals. This fruit is a source of phytochemicals such as carotenoids and phenolic compounds, with health-promoting effects. There is limited information concerning the effect of ripening pattern involving banana peel and pulp bioactive compounds of diverse cultivars. In most studies bananas are assumed at the fully ripe stage to contain the highest phytochemicals. In addition, despite the great diversity of bananas, limited information is available concerning non-traditional underutilized non-Cavendish cultivars and the nutrient content of bananas cultivated within the continental United States. Thus, it is important to identify banana cultivars with significant levels of phytochemicals and encourage the production and consumption of them to take advantage of their health benefits. Accordingly, banana fruits of different genotypes, including ‘Goldfinger’ (AAAB), ‘Hua Moa’ (AAB), ‘Kandarian’ (ABB), ‘Pisang Raja’ (AAB), ‘Saba’ (ABB) and ‘Williams’ (AAA), were analyzed at four ripening stages: mature green, transition, ripe, and overripe. Total carotenoids, carotenoid composition, total phenolics, antioxidant activity, degree of browning, lipid peroxidation, hydrogen peroxide, polyphenol oxidase (PPO), peroxidase (POD), and phenylalanine ammonia-lyase (PAL) enzyme activities were evaluated. Three extraction solvents (methanol-water 50:50; acetone-water 50:50; acetic acid-acetone-water 1:50:49) were utilized to determine optimal extractability and recovery of total phenolic content in banana fruit. Alpha-carotene, β-carotene, and lutein were identified as the major carotenoids in banana. Carotenoid and phenolic content of peels were higher when compared to the pulp in all studied cultivars. Acetic acid-acetone-water provided the most efficient extraction solvent for recovery of phenolics from banana fruit tissue. Overall, ‘Pisang Raja’, ‘Goldfinger’, and ‘Hua Moa’ had the highest carotenoid content. Additionally, ‘Pisang Raja’, ‘Goldfinger’, and ‘Kandarian’ exhibited highest extractable total phenolic content. In terms of browning, ‘Hua Moa’ was the most susceptible cultivar to browning followed by ‘Pisang Raja’, ‘Williams’, ‘Goldfinger’, ‘Kandarian’, and ‘Saba’. Furthermore, PPO and POD were identified as the key enzymes in the browning reaction in the studied cultivars. Results of this study illustrate the importance of cultivar selection and ripening of banana cultivars adaptable to the southeastern U.S. for potential local niche markets and health enhancement of geographically diverse populations.