刺梨中键合态香气物质的释放、活性评价及其前体体内合成-释放机制

Aroma is one of important quality of roxburgh rose fruits and its processing products. The characteristic aroma of roxburgh rose fruits is easy to loss during storage and processing. This will greatly reduce the quality of roxburgh rose fruits and its processing products. Bound aroma precursor can release bound aroma compounds by hydrolysis, and significantly enhance overall aroma of roxburgh rose fruits and its processing products. In this study of bound aroma precursor and its key hydrolysis- synthesis enzymes in wild roxburgh rose fruits as the research objects, using modern food separation and detection technology, releasing control of bound aroma compounds is studied in roxburgh rose fruits. And the composition of glycosyl and aglycone in bound aroma precursors is studied. And releasing effect of glycosidically bound aroma compounds in processing of roxburgh rose fruits and its evaluation of active aroma are studied. And accumulation of bound aroma precursors in growing process of roxburgh rose fruits and change rule of glycoside hydrolases and transferase activity are studied. These are in order to analysis the influence factors in micro balance of synthesis - release of bound aroma precursor in wild roxburgh rose fruits, and to make clear the contribution of overall aroma quality of bound aroma precursor to roxburgh rose fruits, and to clarify synthesis-releasing mechanism of bound aroma precursor in roxburgh rose fruit bodies. This will provide theoretical basis for anabolism control of bound aroma precursor in roxburgh rose fruits, effective release and control of increasing aroma in processing of roxburgh rose fruits.

香气是刺梨果实及其加工制品的重要品质之一。刺梨的特征香气在其加工和贮藏过程中容易损失，极大地降低了刺梨果实及其加工制品的品质。据报道，键合态香气前体经水解可释放出键合态香气物质，能显著增强水果及其加工品的整体香气。本研究以野生刺梨中键合态香气前体及其水解合成关键酶为研究对象，采用现代食品分离和检测技术，通过研究刺梨果实中键合态香气物质的调控释放及其香气前体中糖基与配基的组成，刺梨果加工过程中键合态香气物质的释放效果与活性评价，刺梨果实在生长过程中键合态香气前体物的积累及糖苷水解酶和转移酶活性变化规律，分析刺梨果实中键合态香气前体合成-释放微平衡的影响因素，以明确刺梨中键合态香气前体对刺梨果实整体香气品质的贡献，阐明刺梨果实中键合态香气前体体内合成-释放机制，为刺梨中键合态香气前体合成代谢的调控、有效释放及其刺梨果在加工中的增香调控奠定理论基础。

香气是刺梨果实及其加工制品的重要品质之一。刺梨的特征香气在其加工和贮藏过程中容易损失，极大地降低了刺梨果实及其加工制品的品质。据报道，键合态香气前体经水解可释放出键合态香气物质，能显著增强水果及其加工品的整体香气。采用现代食品分离和检测技术，主要研究了刺梨皮渣和籽仁中的游离态和键合态香气物质，刺梨果加工过程中键合态香气物质的释放效果与活性评价，刺梨果实中键合态香气物质的调控释放及其香气前体中糖基与配基的组成，刺梨果醋醋酸发酵过程中挥发性成分和有机酸的变化规律，电子鼻和电子舌用于刺梨汁整体风味的分析与评价，刺梨果实在生长过程中键合态香气前体物的积累及糖苷水解酶和转移酶活性变化规律等。结果表明：（1）刺梨皮渣中游离态香气物质有21种，萜烯类物质最丰富，其次是酯类物质和酮类物质；检出的键合态香气物质也有23种，其中酸类物质最为丰富，其次是酚类物质和醇类物质。（2）刺梨汁中游离态和O-糖苷键合态香气活性物质分别有23 种和17 种。构成刺梨汁游离态香气活性物质主要有丁酸乙酯（青草）、正己醇（酒香）、正辛醇（甜香）、异戊酸乙酯（菠萝香）、叶醇（茶香）、苯乙烯（果香）、月桂烯（甜香脂）和芳樟醇（柠檬香）等。而构成刺梨汁O-糖苷键合态香气活性物质有3-羟基己酸乙酯（水果香）、2-庚醇（柠檬香）、3-羟基丁酸乙酯（果香）、叶醇（茶香）、正辛醇（甜香）、苯乙醇（玫瑰香）和2′-羟基-4′,5′-二甲基苯乙酮（花香、甜香）等。（3）刺梨果汁和皮渣中糖苷键合态香气前体物的糖基为甘露糖和半乳糖。刺梨籽仁中糖苷键合态香气前体物的糖基为甘露糖、半乳糖和阿拉伯糖。（4）电子鼻和电子舌能准确区分不同品种、不同成熟度、不同贮藏期和不同浓度刺梨样品的整体气味和味道，并能识别和判定未知样品的浓度。此研究成果为刺梨中键合态香气前体合成代谢的调控、有效释放及其刺梨果在加工中的增香调控奠定了理论和实践基础。