广东河源客家黄酒氨基酸分析

为分析广东客家黄酒关键工艺中的炙酒、贮藏、原料等对客家黄酒氨基酸的组成、含量及呈味特性的影响,采用日立氨基酸自动分析仪分析检测客家黄酒中的氨基酸含量,通过计算氨基酸分值、味道强度值(DoT)等确定各氨基酸对客家黄酒的影响。结果表明,客家娘酒中总氨基酸含量在2658.99mg/L- 5420.632mg/L之间,黑豆娘酒氨基酸含量及总量最高,商品板栗娘酒氨基酸含量最低,客家黄酒中最主要的氨基酸是谷氨酸和天冬氨酸,两者合计占氨基酸总量的20%以上,而胱氨酸、蛋氨酸和苯丙氨酸含量最低,是限制性氨基酸。板栗娘酒氨基酸含量低于传统的糯米娘酒,商品板栗娘酒总氨基酸含量仅为糯米娘酒总氨基酸的49%,必需氨基酸仅为64.69%,脯氨酸和苯丙氨酸含量为糯米娘酒的80%,其余氨基酸仅仅达到50%左右。黑豆娘酒比糯米娘酒总氨基酸含量提高42.6%,必需氨基酸提高23.2%,其中胱氨酸提高1倍,脯氨酸提高92.5%,谷氨酸提高80.7%,甘氨酸和丙氨酸提高40%以上,苏氨酸、丝氨酸、异亮氨酸提高30%以上,天冬氨酸、亮氨酸、酪氨酸提高20%以上。炙酒、贮藏过程能降低氨基酸含量,炙酒后氨基酸总量降低20.3%,炙酒后每一种氨基酸含量都明显降低,其中降低最明显的是蛋氨酸和苯丙氨酸,降低氨基酸含量可达50%,苏氨酸、甘氨酸、胱氨酸、赖氨酸、精氨酸在炙酒过程中降低1/3以上,而亮氨酸、异亮氨酸、组氨酸在炙酒过程中氨基酸降低20%以上；贮藏1年以后氨基酸总量降低12.4%,必需氨基酸降低10.9%,组氨酸和精氨酸降低20%以上,除蛋氨酸和苯丙氨酸以外,其余氨基酸均降低10%以上。计算不同酒样的氨基酸的味道强度即剂量比域因子DoT的排序为Glu ＞ Asp ＞ His ＞ Ala ＞ Lys ＞ Tyr ＞ Ile ＞ Gly,只有谷氨酸(Glu)的DoT 值大于1,说明黄酒中决定口味的氨基酸主要是谷氨酸。本文提出味道指数(Taste Index,TI)作为总体风味的评价指标,其定义为优味氨基酸的味道强度之和与劣味氨基酸的味道强度之和的比值,如果TI > 1,说明风味良好,如果TI<1,则劣味氨基酸占优势,味道不佳。本试验中黄酒的TI指数排序为：商品黑豆娘酒 ＞ 绍兴古越龙山花雕酒 ＞ 商品板栗糯米酒 ＞ 贮藏1年的板栗糯米原酒 ＞ 炙酒后的原酒 ＞ 商品普通糯米酒 ＞ 炙酒前原酒 ＞ 1 。对酒样的氨基酸评价表明,AAS和CS评分排序为炙酒前原酒 > 黑豆商品娘酒> 普通商品糯米酒 > 炙酒后原酒 > 贮藏1年的原酒 > 古越龙山花雕酒 > 商品板栗糯米酒,说明炙酒前酒样和黑豆酒样氨基酸的营养价值较好。

Analysis of amino acids for Hakka rice wines from Guangdong Heyuan

To comparatively analyze the composition, contents and taste characteristics of amino acids in 7 kinds of Hakka rice wines from Heyuan city of the Guangdong province, automatic amino acid analyzer was used to detect the amino acids. Moreover, the Dose-over-threshold factor,DoT was calculated to determine the contribution rate of amino acids to the taste of Hakka rice wines. The total amino acid contents of Hakka rice wines are from 2658.99mg/L to 5420.632mg/L, the content of total amino acid and amino acids for black soybean wine are highest among all the 7 rice wines, the chestnut rice wine stored for 2 years is the lowest in content, the main amino acids in Hakka rice wine are glutamic acid and aspartic acid, both of which account for more than 20% of the total amino acids in every rice wine, while cystine, methionine and phenylalanine are the lowest in 17 amino acids for test,, which are limiting amino acids. The contents of amino acids in chestnut rice wine is lower than that in traditional rice wine, the total amino acid content in commercial chestnut rice wine are only 49% of the total amino acids, 64.69% of the essential amino acids, 80% of the proline , 80% of the phenylalanine, and only 50% of the rest amino acids compared with traditional rice wine. While compare with traditional rice wine, the content of total amino acids in black soybean wine rose by 42.6%, and the essential amino acids increased by 23.2% , cysteine was doubled, proline was increased by 92.5%, glutamic acid was increased by 80.7%, glycine and alanine were increased by more than 40% respectively, the threonine, serine and isoleucine were increased by more than 30% respectively, aspartic acid, leucine and tyrosine were increased by more than 20% respectively. The content of total amino acid in wine was reduced by 20.3% in the process of heating, all amino acids were reduced in the heating, especially the contents were reduced by 50% in methionine and phenylalanine respectively, and the content of threonine, glycine, cysteine, lysine and arginine can be reduced by more than 1 / 3 in the process of heating, while leucine and isoleucine can be reduced by more than 20.3%, the contents of histidine decreased by more than 20% in the process of heating wine. After storage for one year, the total amino acids decreased by 12.4%, essential amino acids decreased by 10.9%, histidine and arginine decreased by more than 20%, and all amino acids except methionine and phenylalanine decreased by more than 10%. The taste dose-over-threshold factor (DoT) of amino acids in different wine samples was calculated, the order of DoT was Glu > ASP > His > Ala > Lys > Tyr > Ile > Gly, only the DoT value of Glu was greater than 1, which indicated that the glutamic acid is the most important one in the rice wines, and it determines the taste for rice wines. In this paper, the taste index (TI) is put forward, and the concept of taste index is defined as the ratio of the sum of the DoT for the Umami taste plus Sweet amino acids to the sum of the DoT for the Bitter taste plus Salty amino acids, if TI > 1, the flavor is good, if TI < 1, the inferior amino acids are dominant and the taste is not good. The order of TI is , black soybean rice wine > Shaoxing Guyue Longshan Huadiao rice wine > chestnut rice wine > chestnut rice wine stored for one year > raw rice wine after heat > traditional Hakka rice wine > raw rice wine before heat > 1. The evaluation of amino acids and the order of AAS and CS was as follows for wine samples, raw wine before heating > black soybean rice wine > traditional Hakka rice wine > raw wine after heating > raw wine stored for one year > guyuelongshan Huadiao wine > chestnut rice rice wine, which indicated that the nutritional value of amino acids for raw wine before heating and black soybean rice wine was better than others.