A Research on the Changes in Components of Sulnong Soup Stock with Heating Times

설농탕 주재료의 가열시간별 성분변화에 관한 연구

Followings are the obtained results from the experiment of changes in content of proximate composition, free amino acid and nucleotides in soup prepared from beef brisket, leg bone, tripe and small intestine according to the diverse heating times-3, 6, 12, 18, 24, 30 hrs. The content of moisture in each sample is decreased from 97∼99％ in 8 hours heating to 95∼97% after heating 30 hours. On the contrary, the content of crude protein and crude fat are gradually increased in proportion to the length of heating times and it showed a rapid increasement when it was boiled 6∼12 hours long. We can extract the most protein from the soup stock of tripe among all samples ana the most crude fat from the leg bone. The contents of free amino acids is gradually increased in proportion to the length of heating times. Especially after being boiled longer than 18 hours it is increased obviously. In the soup stock prepared from the brisket, the lysine and alanine were contained the most. In leg bone soup stock, glutamic acid and histidine were extracted the most but bone soup stock, glutamic acid contents were decreased a little in longer heating. In the soup stock of tripe, glutamic acid which is contained very little in a raw material was extracted more as increasing times. In the soup stock of small intestine, lysine and glutamic acid were extracted the most. The least content in free amino acid from each sample was cystine which is sulphur-containing amino acid. These result suggest that, in order to get enough extraction of amino acid, crude fat, 18 hours heating is the most useful while 5’-IMP, which is the taste compound of meat, is extracted at 3 hours heating.