新鲜和陈化莲籽化学成分和功能特性的比较

莲籽在贮藏过程中,其蒸煮特性及食味均会发生明显变化,导致莲籽陈化变质。为了解这一变化的内在原因,以新鲜和陈化的广昌通心白莲为试验材料,对2种莲籽的吸水性和吸油性、乳化性和乳化稳定性、发泡性和泡沫稳定性、胶凝性等功能特性和化学成分变化进行了对比研究。研究结果表明,新鲜和陈化莲籽的水分、粗脂肪、蛋白质含量及醇提取物HPLC图谱相似度差异都不显著,但其他化学成分有显著差异,且各种功能特性存在较大差异,陈化莲籽的脂肪酸值、直链淀粉含量显著增加,支链淀粉和巯基含量显著降低,吸水性和吸油性、乳化性、发泡性、胶凝性等方面都有所降低。贮藏导致莲籽蛋白质、脂类和淀粉等化学成分的结构发生变化,从而使其功能特性发生了相应的改变。

Comparative Study on Chemical Composition and Functional Characteristics of Fresh and Aging Lotus Seeds

The cooking properties and taste values of lotus seeds will significant change during storage due to deterioration. To understand the causes of the change,fresh and aging lotus seeds from Guangchang were used as material to investigate their functional characteristics. The results indicated that the difference between contents of moisture,protein,crude lipid and HPLC fingerprint of 80% methanol extracts in fresh and aging lotus seeds were not significant. But the other chemical composition and the functional characteristics were significantly different between them. The fatty acid value and amylose content increased,the amylopectin and sulfhydryl content were significantly reduced. The capacity,including water absorption,oil absorption,emulsion activity,foaming capacity and gelation properties of aging lotus seeds were decrease remarkably compared with fresh seeds. Aging could lead the change of composition and structure which affect the lotus seeds functional characteristics.