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Partial least squares regression (PLSR) modeling was performed to predict the moisture content in steamed, dried purple sweet potato based on spectral data obtained from hyperspectral imaging analysis. The PLSR model with a combination of multiplicative scatter correction, Savitzky-Golay, and first derivative exhibited the highest accuracy (R P 2 = 0.9754). The wavelengths found that strongly affected the PLSR model were 961.12, 1065.50, 1083.93, 1173.23, and 1233.89 nm. These wavelengths were associated with the O-H second overtone and the second overtone of C-H, C-H 2 , and C-H 3 . When PLSR modeling was performed using these selected wavelengths, the prediction accuracy of the PLSR model exhibited high accuracy (R P 2 = 0.9521). Therefore, the moisture content could be predicted with high accuracy using only five wavelengths rather than the full spectrum.

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The purpose of this study was to evaluate the quality of fresh-cut lettuce after a washing treatment with differing concentrations of mixed natural extract. Five different treatments were employed: distilled water, sodium hypochlorite (Cl), 20% mixed natural extract (Na-1), 60% mixed natural extract (Na-3), and 100% mixed natural extract (Na-5). Measurements of carbon dioxide concentration, enzymatic activities, total aerobic bacteria, and sensory evaluation were investigated on day 1, 2, 3, and 5 at 5℃. The CO 2 concentration in lettuce treated with Cl was significantly higher than that in other samples on day 5, and it remained generally low during the storage period in that treated with Na-5. The enzymatic activities (POD (peroxidase) and PAL (phenylalanine ammonia lyase) activities) in lettuce treated with Na-5 and Na-3 were low during the storage, and were significantly higher in lettuce treated with Cl than that in other samples on day 5. Total aerobic microbial count increased during storage, specifically on day 5, and was 6.53±0.08 log CFU/g in lettuce treated with Cl, while those in lettuce treated with Na-5 was 6.22±0.18 log CFU/g and significantly different. In case of sensory evaluation, there was no significant difference between the washing treatments in off flavor and smell. Color and overall acceptability in Na-5 was higher than that treated with Cl. The results revealed that the washing treatment of mixed natural extracts primarily containing rosemary extracts could be used to wash fresh-cut lettuce.

The purpose of this study is to present the results as basic data for establishing proper storage conditions and distribution conditions of actual farms at point of increasing concern about hygiene and palatabiltiy of consumers to food. In this study, three farmhouses of dried persimmons prepared using different storage conditions were selected in Sangju (Korea). The dried persimmons were stored for 90 days. Changes in temperature and humidity were measured with a temperature and humidity recorder under each storage condition, and physicochemical analysis and sensory evaluation were performed. The average temperatures of farmhouse A, B and C were approximately-22-23℃,-19-18℃ and-25℃ respectively. The humidities of A, B and C were 62-63%, 59-60%, and 66-67%, respectively, and the moisture contents of all farmhouses increased during the storage period, with farmhouse B showing the most rapid increase. Free sugars increased, except for those from farmhouse C. Persimmons from farmhouse B showed the greatest changes in chewiness and hardness. The values of a * and b * were significantly decreased in persimmons from farmhouse B, and the color difference value of farmhouse B was dramatically increased. Sensory evaluation showed that the color preference tended to decrease compared with the initial value. Only farmhouse B showed decreased overall acceptability. Moreover, farmhouse B had the highest storage temperature and lowest humidity. Therefore, our results showed that storage at a low temperature and high humidity was important for manufacturing high-quality dried persimmons.