Effect of Heat Treatments on the Chemical Compositions of Flesh in Chestnut Processing

밤 가공시(加工時) 열처리(熱處理) 방법(方法)이 과육성분(果肉成分)에 미치는 영향(影響)

The changes in chemical compositions of chestnuts were tested during processing in order to elucidate the effects of heat treatments such as boiling, steaming and roasting on the flesh compositions. The results obtained were as follows. 1. The chemical compositions of raw chestnuts were: moisture, 59-61%; total sugar, 24-27%; crude fat, 0.3%; crude fiber, 0.6-0.9%; ash, 1.0%; amino nitrogen, 0.3%; vitamin C, 20-22 mg%; and tannin, 40-48%. 2. The moisture contents were increased to 63.8% by the boiling and to 70.27% by the peeling and boiling from 59.41% of raw ones respectively, whereas decreased to 54.11% by the roasting. 3. Contents of crude protein were decreased to 8.04% by the peeling and boiling procedure from 8.72% of raw ones, and those of amino nitrogen also revealed a decreasing tendency by the heat treatments. However, no significant change was observed in crude fat content. 4. Total sugar contents were decreased by the peeling and boiling procedure approximately 3.0%, whereas reducing sugars were increased 2 to 3 times in the all treatments. 5. Vitamin C contents were decreased 72.0 to 78.0 % by the boiling procedure, 64.2% by the steaming, 51. 6% by the roasting as compared with the raw ones. Tannin contents were increased 11.0% by the boiling, and 46.0% by the roasting respectively, whereas decreased 22.0% by the peeling and boiling procedure. 6. The color was changed to brown with different degree, during the boiling, steaming and roasting procedure. The 0.1% solution of alum appeared to be effective in reducing the browning reaction during the heat treatments.

밤의 가공시(加工時) 열처리방법(熱處理方法)이 밤의 과육(果肉)성분에 미치는 영향을 규명하기 위하여 수자(水煮), 증자(蒸煮), 배초처리(焙焦處理)에 따른 밤의 화학성분(化學成分) 변화(變化)를 검토하여 다음과 같은 결과를 얻었다. 1. 원료(原料)밤의 화학성분(化學成分)은 수분(水分) 59~61%, 총당(總糖) 24~27%, 환원당(還元糖) 0.3%내외(內外), 조단백질(粗蛋白質) 3% 내외(內外), 조지방(粗脂肪) 0.3~0.4%, 조섬유(粗纖維) 0.6~0.9%, 회분(灰分) 1%, amino 태질소(態窒素) 0.3%, vitamin C 20~22mg%, tannin 40~48mg%이었다. 2. 생(生)밤의 수분함량(水分含量)은 59.41%, 수자처리(水煮處理)한 밤은 63.80%, 박피(剝皮)하여 수자처리(水煮處理)한 밤은 70.27%로 증가하였고 배초처리(焙焦處理)한 빔은 54.11%로 감소하였다. 3. 조단백질(粗蛋白質) 함량(含量)에 있어서 생(生)밤은 8.72%, 박피(剝皮)하여 수자처리(水煮處理)한 밤은 8.04%로 감소하였고 amino태질소(態窒素) 함량(含量)은 모든 처리(處理)에 있어서 감소의 경향을 나타냈으며 조지방(粗脂肪) 함량은 별 변화(變化)가 없었다. 4. 총당함량(總糖含量) 변화(變化)는 박피(剝皮)하여 수자처리(水煮處理)한 밤과 배초처리(焙焦處理) 밤은 생(生)밤보다 3% 정도 감소하였고 환원당(還元糖) 함량에 있어서는 모든 처리에 있어서 2~3배 정도 증가하였다. 5. Vitamin C 함량의 변화(變化)에 있어서는 수자처리(水煮處理)한 밤은 생(生)밤에 비하여 72~78%, 증자(蒸煮) 처리(處理)한 밤은 64.2%, 배초처리(焙焦處理)한 밤은 51.6% 감소하였으며 tannin 함량에 있어서는 수자처리(水煮處理)한 밤이 11.0%, 배초처리(焙焦處理)한 밤은 46.0% 정도 증가하였고 박피(剝皮)하여 수자처리(水煮處理)한 밤에 있어서는 22.0% 정도 감소하였다. 6. 배초(焙焦), 증자(蒸煮), 수자처리(水煮處理)한 밤의 색도(色度)는 심한 갈변(褐變)현상을 나타냈으며 0.1% $K_2Al_2(SO_4){_4}{\cdot}24H_2O$ 용액중(溶液中)에서 수자처리(水煮處理)한 밤은 색도(色度)의 변화(變化)가 없었다.