大蒜酒製程及乙醇溶液中Alliin穩定性之研究

Abstract

大蒜一直以來被認為是藥食同源的食材，許多文獻指出，大蒜中含有相當多具有機能性的含硫化合物，對人體有保健功效。大蒜酒是利用酒精浸泡大蒜而製成的傳統大蒜加工產品，但由於其蒜味濃厚，導致消費者不容易接受，加上大蒜酒中的活性物質亦鮮少有人探討，故難以凸顯出大蒜酒的優點及商品價值。 本研究分為兩部分，第一部分為藉由不同的殺菁處理方式 (熱水殺菁、微波殺菁、熱風殺菁及無殺菁)，探討大蒜酒加工過程中產品品質和活性物質蒜胺酸 (alliin) 含量的變化。結果顯示，蒜酒浸漬62天時alliin的含量係以熱水殺菁的處理組別最高，約2584.23±45.21ppm，比未殺菁處理 (1491.29±159.17ppm) 為高，表示殺菁處理確實可以保留大蒜中之alliin。而感官品評結果發現，熱水殺菁處理的蒜酒，雖然蒜味程度最低，但以整體接受性，仍以其他組別的蒜酒較高。 第二部份則進一步探究alliin在不同環境下，包括乙醇濃度 (0-40%)、pH (2-7) 和溫度 (60-80℃) 等對其穩定性的影響，結果顯示，alliin在低酒精濃度 (0-20%) 的環境下，降解的速率較慢，增加酒精濃度至40%，其降解程度為最快。在pH的影響方面，alliin在pH5時保留率最高，提高至pH7或降低至pH2時都會加速alliin的降解，其中又以pH2降解最快。儲藏溫度對溶液中alliin的安定性也有很大的影響，當儲藏溫度提高時，alliin的降解有顯著性的升高趨勢。由以上結果可觀察出alliin在乙醇溶液中可能的變化情形，並提供作為大蒜酒加工製程改善時之參考。

Garlic is always considered as a food with medicinal property. Many reports indicated that garlic contains a lot of functional sulfur-containing components, which are good for human health. Garlic liqueur is a traditional processing product produced by soaking garlic in alcoholic solution. However, garlic is not usually well accepted by consumers due to its odor and pungent flavor. In addition, little is known about the active components in garlic liqueur. The value of this commodity needs more investigation. This study includes two parts, the first part is to study the changes of the product quality and alliin content in different blanching treatments (boiling water; microwave; hot air; non-blanching as control). The results show that after soaking garlic for 62 days, the alliin content of boiling water treatment is 2584±45ppm, which is higher than that of the non-blanching treatment, 1491±159ppm. It reveals that the practice of blanching can reserve alliin in garlic. Sensory evaluation revealed that, the odor of garlic liqueur treated by boiling water is the lowest, but the overall acceptances of the other groups are better. The second part is to study further about the stability of alliin under different circumstances, including the effects of ethanolic concentration (0-40%), pH value (2-7) and temperature (60-80℃). The results show the degradation rates of alliin are slower at low ethanolic concentration (0-20%), and highest as the concentration is raised to 40%. In terms of pH, the retention of alliin is highest at pH5, both increasing and decreasing the pH would accelerate the degradation of alliin. Fastest reduction occurs at pH2. Moreover, the temperature of storage affects alliin’s stability pronouncedly. The degradation of alliin is increased while raising the temperature.