雞精滴為依古老方法高溫長時間熬製而成，具有提升體內抗氧化能力及延緩老化的功能。雞精成分含有肌肽、牛磺酸及支鏈胺基酸等游離胺基酸。本研究旨在分析不同性別與週齡雞隻製造之雞精中游離胺基酸之組成。分別飼養白羽烏骨雞一批，海蘭蛋雞二批，白羽烏骨雞於週齡10週、20週及30週時取公母各二隻製作滴雞精，海蘭蛋雞取週齡30週及110週各二隻製作滴雞精，另購買五週齡之母白肉雞製作滴雞精，並分析各雞精產量及其游離胺基酸之含量。結果顯示，烏骨雞去內臟脂肪後屠體平均重量公雞較母雞為重，每隻公雞雞精產量有比母雞多約20％之趨勢，並以20週齡之產量最高。烏骨雞雞精中游離胺基酸主要以肌肽及其衍生物甲肌肽為主，合計占約62.4％，其次為牛磺酸約11.5％，麩胺酸占5.8％，丙胺酸3.8％，支鏈胺基酸2.6％。以雞精品質而論，超過80％以上的功能性游離胺基酸(肌肽及支鏈胺基酸合計)在性別及週齡方面均無顯著差異。因此，純粹從雞精的產量來考量，以烏骨雞做為原料來源時，以20週齡的公雞最為有利。
The traditional way of making drop chicken essence is to cook for a long time at high temperature. It can enhance the antioxidant capacity and prolong the aging of the human body. Drop chicken essence contains free amino acids, such as carnosine, taurine and branch-chain amino acids. In this study, we investigated free amino acids profile of drop chinken essence from chicken with different gender and ages. White feathered silky chickens and hyline laying hens were raised using commercial standard diet and protocal. Silky chickens were slaughtered at 10, 20 and 30 weeks-of-age and used to produce drop chicken essence. Laying hens were slaughtered at 30 and 110 weeks-of-age for the same purpose. Broiler chickens (5 wk-of-age) were purchased from local poultry farm. All chicken essenses were analyzed for the yield and free amino acids profile. The results showed that the average carcass weight of male silky chickens was greater than that of female chicken, but the yeild of chicken essence was not significantly different although the male tended to produce 20% more than the female did and was the most at 20 wks-of-age. The main amino acids in chicken essence were carnosine and its derivatives, which accounted for 62.4%, followed by taurine (11.5%), glycine (5.8%), alanine (3.8%) and branch chian amino acids (2.6%). As far as quality is concerned, there is no significant difference in functional amino acids (over 80%) among sexes or ages. Therefore, it is suggested that the male silky chickens at 20 wks of age is the most advantageous for chicken essence production.
