苹果渣发酵过程中游离氨基酸和挥发性香气成分分析

Analysis of Free Amino Acids and Aroma Components in Fermented Apple Pomace

为提高苹果渣的利用价值,采用固态发酵法发酵苹果渣制备单细胞蛋白,并通过氨基酸自动分析仪及气相色谱-质谱联用技术对苹果渣制备单细胞蛋白的营养及风味进行分析。结果表明:苹果渣发酵前后游离氨基酸含量由3.25 mg/mL增加至15.68 mg/mL,呈味氨基酸含量由2.73 mg/mL增加至11.45 mg/mL,7种必需氨基酸含量由0.87 mg/mL增加至5.33 mg/mL;苹果渣经过发酵后挥发性香气成分由发酵前的17种增加到38种,芳香族化合物的种类及含量有所增加,并新产生了酯类、呋喃类、含氮类化合物;发酵后苹果渣香气浓郁,风味得到显著改善。

The contents and kinds of free amino acids(FAAs) in apple pomace and fermented apple pomace were determined by amino acid analyzer. The aroma components in the unfermented and fermented samples were identified by gas chromatography-mass spectrometry(GC-MS). Results showed that the content of FAAs was increased from 3.25 to 15.68 mg/mL, and the content of flavor amino acids was increased from 2.73 to 11.45 mg/mL after fermentation. Fermented apple pomace contained 7 essential amino acids and their total content was increased from 0.87 to 5.33 mg/mL. Seventeen and thirty eight volatile compounds were identified in the unfermented and fermented apple pomace, respectively. The types and contents of aromatic substances were increased. In the fermented apple pomace, esters, furans, and nitrogen-containing substances were produced. Fermentation improved the flavor of apple pomace.