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)

  • Shin, Doo Ho (Graduate School, Chungnam Natl. Univ.) ;
  • oh, Man Jin (Dept. of Food Science and Technology, Coll. of Agriculture, Chungnam Natl. Univ.) ;
  • Kim, Seung Yeol (Dept. of Food Science and Technology, Coll. of Agriculture, Chungnam Natl. Univ.)
  • Published : 1981.06.30

Abstract

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.

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