Location: Tropical Crop and Commodity Protection Research
Title: Nutritional, physicochemical, and functional properties of Hawaiian taro (Colocasia esculenta) flours: A comparative studyAuthor
SAXBY, SOLANGE - University Of Hawaii | |
DONG, LIANGER - University Of Hawaii | |
HO, KACIE - University Of Hawaii | |
LEE, CHIN - University Of Hawaii | |
Wall, Marisa | |
LI, YONG - University Of Hawaii |
Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/12/2024 Publication Date: 4/5/2024 Citation: Saxby, S., Dong, L., Ho, K., Lee, C.N., Wall, M.M., Li, Y. 2024. Nutritional, physicochemical, and functional properties of Hawaiian taro (Colocasia esculenta) flours: A comparative study. Journal of Food Science. 89(5):2629-2644. https://doi.org/10.1111/1750-3841.17053. DOI: https://doi.org/10.1111/1750-3841.17053 Interpretive Summary: Taro is a nutrient-dense staple food of Asian-Pacific populations. Flours derived from five Hawaiian taro varieties were evaluated for nutritional, physicochemical, and functional properties important for food formulation. The unique starch structure of taro, water and oil absorption indices, foaming capacity, and emulsifying stability were determined. The results show that Hawaiian taro flours possess excellent functional properties, potentially enhancing food quality as an alternative additive during food processing. Technical Abstract: Taro (Colocasia esculenta), a nutrient-dense tuber, is a staple food in Asia, Africa, South America, and the Pacific. Mitigating post-harvest losses through taro processing into flour offers a valuable means of extending shelf-life. Additionally, it serves as a viable carbohydrate substitute and a functional additive for food formulation. However, different taro varieties may possess distinct characteristics that can influence food production. This study aimed to evaluate flours derived from five Hawaiian taro varieties, Bun-Long, Mana Ulu, Moi, Kaua'i Lehua, and Tahitian, for their nutritional, physicochemical, and functional properties. Results showed significant differences among the five taro varieties. Tahitian, Bun-long, and Moi had high total starch content of 40.8, 38.9, and 34.1 g/100 g, respectively. Starch structure of taro demonstrated a Type-A crystallinity pattern, with the diameter of taro starch granules varying from 2.08 µM for Mana Ulu to 2.93 µM for Tahitian. Potassium was an abundant mineral in all tested taro varieties, ranging from 1.29 to 1.75%. Notably, the Hawaiian taro flours exhibited higher water absorption and water solubility indexes when compared to cassava and yam flours, showcasing values of 5.68 g/g for Moi and 33.3 g/100 g for Tahitian. Furthermore, the functional properties of the tested taro flours were assessed, including water absorption capacity (0.93-3.48 g/g), oil absorption capacity (1.25-3.15 g/g), foaming capacity (4.67-28.33 mL/100 mL), emulsifying activity (19.33-36.67%), emulsifying stability (12.67-32.67%), and swelling capacity (1.20-2.07 g/g). Remarkably, Tahitian flour showed the highest values of all these functional properties, as well as superior foaming stability. The bulk density of the five taro flours ranged from 0.59 g/mL for Mana Ulu to 0.66 g/mL for Tahitian. The gelling and boiling points were observed within the temperature ranges of 62.33-68.33'C and 72.33-79.67'C, respectively. To sum up, Hawaiian taro flours possess excellent functional properties, potentially enhancing food quality as an alternative additive during food processing. |