Feasibility of rapid brix prediction in sweet potatoes using a handheld near-infrared spectrometer

Sweetness and texture are key factors in determining sweet potato quality, but traditional evaluation methods often permanently destroy the product. In this study, we utilized a cost-effective handheld near-infrared (NIR) spectrometer (operating at 900–1,700 nm) to assess Brix and moisture content of yellow-fleshed Japanese sweet potato cultivars grown in Memuro, Hokkaido. Measurements were taken across the growth and storage stages. Spectral data showed that the tip of the sweet potato root showed consistent patterns, making it effective for Brix prediction, with model ratio of prediction to deviation of 2.5.