廃棄される皮を利用したレンコン茶の食品学的特性

Characteristics of Lotus Root Tea Made from Discarded Peels

Objective: This study aimed to develop a prototype using lotus root peels, byproducts of lotus root processing, to evaluate their suitability as a healthy tea and elucidate their characteristics.
Methods: The edible portions and peels of Iwakuni lotus root purchased in March, 2024 were used as samples. The sliced samples were dried in a ventilated dryer at 50 ℃ for 20 h. Subsequently, the dried edible portions were roasted in an oven at 150℃ for 10 min or 180℃ for 5 min, whereas the dried peels were roasted at 150℃ for 5 min or 180°C for 5 min. Extracts were prepared by adding 100 mL of boiling water to 4 g of the crushed roasted samples and steeping for 5 min. Using these extracts, color differences (L*, a*, and b* values), potassium and polyphenol levels, and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity were measured, and taste analysis, aroma analysis, and voluntary tasting surveys were conducted.
Results: Notably, no significant color difference was observed between the edible portions and peels at the same roasting temperature and time. The extract made from the peels exhibited higher potassium and polyphenol levels and DPPH radical scavenging activity than the tea made from the edible portions. In taste analysis, compared to commercial barley tea used as a control, the extract made from the edible portions showed higher saltiness and umami flavor, whereas the tea made from the peels showed higher astringency and bitterness. Aroma analysis revealed that aroma components associated with burning increased with increasing roasting temperature and time. Sensory evaluation revealed that the extract made from the edible portions roasted at 180℃ for 5 min was the most preferred, followed by that made from the peels.
Conclusion: Lotus root extract made from the peels exhibited higher potassium and polyphenol levels than that made from the edible portions, consistent with the overall evaluation results of the tasting surveys. Overall, these results suggest that the lotus root peel extract shows potential as a healthy tea.

Creators TAKANO Momoka

Creators HITOMI Eri

[EISSN]2189-4825