五种魔芋中主要营养成分及重金属元素分析

采用分光光度法、全自动凯氏定氮法、索氏抽提法和电感耦合等离子体质谱(ICP-MS)检测技术对白魔芋(Amorphophallus albus)、黑魔芋(Amorphophallus nigrum)、滇魔芋(Amorphophallus yunnanensis Engl)、珠芽魔芋(Amorphophallus bulbifer)和汀盛1号魔芋中葡甘露聚糖、蛋白质、脂肪、粗纤维和重金属元素进行测定分析。结果表明,魔芋中的葡甘露聚糖含量较为丰富,可达干质量的60%左右,脂肪含量较少为0.06%~0.54%之间,蛋白质含量为4.16%~7.86%,粗纤维含量为3.10%~4.70%,重金属元素中Mn含量最高,为8.170~53.290 mg/kg,其中黑魔芋中最高为53.290 mg/kg,且不同品种的魔芋中葡甘露聚糖、脂肪、蛋白质、粗纤维、微量元素的含量均有显著差异,但白魔芋整体营养价值最高。本研究可为当前发展林下特色产业,选择魔芋种植品种、魔芋市场价值定位和精深加工等产业链提供理论依据。

Analysis of Main Nutrients and Heavy Metal in Five Konjac

The contents of glucomannan, protein, fat, crude fiber and heavy metal was determined and analyzed by detection techniques of spectrophotometry, automatic Kjeldahl method, Soxhlet extraction and inductively coupled plasma mass spectrometry (ICP-MS) in the Amorphophallus albus, Amorphophallus nigrum, Amorphophallus yunnanensis Engl, Amorphophallus bulbifer and Tingsheng 1.The results showed that the glucomannan content in konjac was the most abundant, reaching about 60% of dry weight, the fat content was at least 0.06%~0.54%, the protein content was 4.16%~7.86%, and the crude fiber content was 3.10%~4.70%, the content of manganese (Mn) in heavy metal was 8.170~53.290 mg/kg, it was the highest up to 53.290 mg/kg in A.nigrum and the content of glucomannan, fat, protein, crude fiber and trace elements in different varieties of konjac was significantly different. On the whole, Amorphophallus albus had the highest nutritional value. This research can provide data support for the current development of under-forest specialty industries, the selection of konjac planting varieties, konjac market value positioning and intensive processing industries.