頁籤選單縮合
題名 | 保久乳之蛋白質營養價值之分析=Nutritional Values of Protein in Sterilized Milk |
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作者 | 梁逸; 黃素女; Liang, I; Huang, Shu-nie; |
期刊 | 畜產研究 |
出版日期 | 19990600 |
卷期 | 32:2 1999.06[民88.06] |
頁次 | 頁199-210 |
分類號 | 473.7 |
語文 | chi |
關鍵詞 | 保久乳; 必需胺基酸; 蛋白營養; Sterilized milk; Essential amino acid; Nutritional protein; |
中文摘要 | 鮮乳與保久乳之營養價值經分析結果,保久乳蛋白質濃度只有鮮乳的91%。保久 乳蛋白質中胺基酸因高溫長時間加熱後有10至15%被焦化成非蛋白胺基酸。而他們之間乳 蛋白之濃度顯著差異主要原因是保久乳高溫加熱製造過程中有較多乳蛋白質起沈澱及焦化粘 在管路或被過濾掉所致。利用酵素分解法比較它們消化率,結果保久乳只有鮮乳75%。比 起鮮乳,保久乳中有25%蛋白質不被胰蛋白 (trypsin)分解。主要原因是保久乳中乳蛋白 之結構比較緊密,且有更多蛋白質與乳糖或脂肪緊密結合,導致酵素不容易分解。測定乳中 胺基酸,結果同體積之乳量中保久乳所含胺基酸平均約只有鮮乳的85%。分析乳中必需胺 基酸當中對不耐熱性之色胺酸,甲硫胺酸含量,本報告將針對牛乳分別提出另一種胺基酸的 測定法如利用紫外線光譜四次微分法測定色胺酸,利用氣體色層分析法測定甲硫胺酸。分析 結果保久乳中色胺酸只有鮮乳60%,而甲硫胺酸只有34%左右。從上述分析結果由於保久 乳消化率差且必需胺基酸顯著的被破壞,因此保久乳之蛋白營養價值遠比鮮乳低。 |
英文摘要 | The protein concentration of Sterilized milk (SM) was about 90% of fresh milk. Ten to 15% of amino acids of SM's protein was released due to the fact that a part of protein precipitated on the wall of pipe line and part of them became non-protein nitrogen compound. The digestibility of SM's protein with trypsin treatment showed that it was about 75% in respect to fresh milk. This meant that a part of SM's protein became rigid form and can not be digested by trypsin. The quantity of each amino acid of SM was 85% that of fresh milk in average. Methionine content in SM was 0.146 mg/ml while in fresh milk it was 0.46 mg/ml as determined by gas chromatography. Tryptophan contents were 0.28 mg/ml and 0.47 mg/ml for SM and fresh milk, respectively, as determined by derivative spectrophotometry. In summarizing the nutritional and biochemical characteristics of SM, it could be stated that considerable changes in the nutritional value of milk took place in SM. Fresh milk is greatly superior to SM in nutritional values. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。