Useful tissues in cabbage head for freshness evaluation with visible and near infrared spectroscopy

To determine which cabbage head tissues are useful for evaluating freshness using spectroscopic technology, we stored wrapped and unwrapped cabbage heads for up to 30 d, and measured visible and near infrared spectra (420-2500 nm) of the 1st-10th leaf layers and cores. We found that spectral changes in leaves were affected both by leaf layer and storage conditions, while continuous spectral changes were observed in the cores regardless of storage condition. These spectral changes in the leaves and cores were consistent with color images and water content. While we developed good models for estimating the storage days from the 1st and 2nd leaf layers and the cores of unwrapped cabbages, only core spectra provided a high correlation with storage days in wrapped cabbages. These data demonstrated that the cabbage core is sensitive to storage duration and its spectra are useful for evaluating freshness decline regardless of storage condition.