甘薯地上部的营养分析及评价

Nutritional Analysis and Evaluation of the Aerial Parts of Sweet Potato

摘要:

为了充分利用甘薯地上部并提高甘薯的附加值，该研究对甘薯叶、柄和茎进行了营养成分分析，并利用主成分分析法及隶属函数法进行了综合评价。研究结果表明，甘薯地上部富含矿质，蛋白质和膳食纤维营养素，约70%的氨基酸属于药用氨基酸和味觉氨基酸，其中，叶中药用氨基酸占总氨基酸的68.15%、柄部占71.48%、茎部占71.64%；叶部中味觉氨基酸占总氨基酸的67.25%、柄部占72.17%、茎部占72.64%。此外，甘薯叶中蛋白质含量为3.8%、锰含量为134 mg/kg、镁含量为4 509 mg/kg、钼含量为0.24 mg/kg。叶中还富含多酚（33.6 mg GAE/g，其中黄酮20.9 mg CE/g）、叶绿素（叶绿素a含量为91.8 mg/100 g、叶绿素b含量为33.14 mg/100 g）以及类胡萝卜素（14.5 mg /100 g）。茎部以膳食纤维（10.6%）、锌（41.8 mg/kg）、硒（0.16 mg/kg）、铬（3.0 mg/kg）以及铁（376.0 mg/kg）含量最高。柄部则富含钙（27 648 mg/kg）、镁（4 376 mg/kg）、钾（26 152 mg/kg）、钼（0.21 mg/kg）。综合营养品质评价结果显示，甘薯地上部不同部位营养品质排序为叶（0.92）>茎部（0.31）>柄部（0.19）（P<0.05）。该研究结果为甘薯地上部叶、柄和茎的有效开发和综合利用提供了重要的理论数据，为未来甘薯地上部的开发指明了方向。

Abstract:

In order to make full use of the aerial parts of sweet potato and increase their added value, in this study, the nutritional components of sweet potato’s leaves, stems and stalks were analyzed, and comprehensive evaluation via principal component analysis and membership function analysis was performed. The results showed that the aerial parts of sweet potatoes were rich in nutrients like minerals, proteins, and dietary fibers, with about 70% of the amino acids belonging to medicinal and taste-active amino acids. Among them, the amino acids used in traditional Chinese medicine accounted for 68.15% of the total amino acids for the leaves, 71.48% for the stalks, and 71.64% for the stems. The taste amino acids accounted for 67.25% of the total amino acids for the leaves, 72.17% for the stalks, and 72.64% for the stems. Sweet potato leaves contained 3.8% protein, 134 mg/kg manganese, 4 509 mg/kg magnesium, and 0.24 mg/kg molybdenum while having abundant polyphenols (33.6 mg GAE/g; including flavonoids 20.9 mg CE/g), chlorophyll (91.8 mg/100 g chlorophyll-a, 33.14 mg/100 g chlorophyll-b), and carotenoids (14.5 mg/100 g). The stem contained the highest levels of dietary fiber (10.6%), zinc (41.8 mg/kg), selenium (0.16 mg/kg), chromium (3.0 mg/kg), and iron (376.0 mg/kg). The stalk was rich in calcium (27 648 mg/kg), magnesium (4 376 mg/kg), potassium (26 152 mg/kg), and molybdenum (0.21 mg/kg). The results of the comprehensive nutritional quality evaluation showed that the nutritional quality of different aerial parts of sweet potato was in this order leaf (0.92) > stem (0.31) > stalk (0.19) (P<0.05). This study provides important theoretical data for the effective development and comprehensive utilization of the aerial parts, leaves, stalks, and stems of sweet potato, and points out the direction for future development of the aerial parts of sweet potato.