紫肉甘薯部分营养成分与食味的关联分析

【目的】明确紫肉甘薯的食用品质指标,为食用紫肉甘薯选育提供依据。【方法】测定276份紫肉甘薯品系的花青素含量、干物质含量、熟薯可溶性糖和还原糖含量、食味指标,分析研究紫肉甘薯营养成分与蒸熟后的食味关系。【结果】花青素含量变异系数大,高花青素育种并不困难;‘绫紫’与高糖非紫肉亲本杂交是改良‘绫紫’紫肉F1代食味的最好方法。降低花青素含量群体水平有利于提高食用紫肉甘薯育种效率,花青素含量在90mg·100g-1FW以下仍有较好的高花青素食用甘薯育种效率;干物质含量在27.5%—38%有较好的食用紫肉甘薯育种效率,而最佳育种效率的干物质含量在32%—36.5%;提高熟薯可溶性糖含量群体水平可以有效提高食用紫肉甘薯育种效率。花青素给紫肉甘薯的甜度、香味带来极显著的不利影响,它对食味的不利影响达到熟薯可溶性糖对食味增量贡献的51.30%。干物质含量虽然与紫肉甘薯的质地、香味、粗纤维有极显著正相关,但与黏度呈极显著负相关,与甜度呈接近显著的负相关,因此,干物质含量对紫肉甘薯食味总评的影响很有限。熟薯可溶性糖对紫薯甘薯食味极其重要,它与甜度、黏度、质地存在极显著的正相关,其中的非还原糖与还原糖相比,在甜度、香味、质地上有较多的贡献,熟薯非还原糖对紫肉甘薯食味增量贡献是还原糖的2.3倍。甜度在紫肉甘薯食味评价中占据极其重要的地位,对食味增量的贡献率达到55.38%。【结论】花青素含量和熟薯可溶性糖含量是紫肉甘薯的重要食用品质指标。在食用紫肉甘薯育种上应兼顾营养与食用品质,控制花青素含量在90 mg·100g-1FW以下;在亲本选择上,紫肉亲本与高糖非紫肉亲本杂交是食用紫肉甘薯常规杂交育种的最好方法。

Association Analysis Between Part Nutritional Compositions and Taste of Purple-Fleshed Sweetpotato

【Objective】 The aim of this research is to define the edible quality index and to provide a basis for edible purple-fleshed sweetpotato breeding. 【Method】 The content of anthocyanin, dry matter, soluble sugar and reducing sugar in steamed root, and taste index were measured from 276 purple sweetpotato strains. In addition, the relationships between nutritional compositions and taste of steamed purple sweetpotato were analyzed. 【Result】 As the great variation coefficient of anthocyanin content, it is easy to screen high anthocyanin content varieties in purple sweetpotato breeding. It is the best method that ayamurasaki was crossed with non-purple-fleshed parents containing high sugar to improve the taste of filial purple-fleshed F1 generation of ayamurasaki. Reducing the group level of anthocyanin content would benefit to improve the breeding efficiency of edible purple-flesh sweetpotato. Even thoughanthocyanin content leass than 90 mg·100g^-1FW, there was still a good breeding efficiency of edible purple-flesh sweetpotato with high anthocyanin content. There was a better efficiency of edible purple-fleshed breeding when dry matter content ranged from 27.5% to 38%, whereas the best breeding efficiency for dry matter content was ranged from 32% to 36.5%. Moreover, increasing the group level of soluble sugar content in steamed root would help to improve the efficiency of edible purple-fleshed breeding. Anthocyanin content showed highly significant negative effects on sweetness and fragrance of purple sweetpotato, and its negative effects on taste up to 51.30% of taste incremental contribution from soluble sugar. Dry matter content was highly significantly positively correlated with texture, fragrance, and coarse fiber of purple sweetpotato, but it was highly significantly negativelycorrelated with viscosity, and was closely significantly negatively correlated with sweetness. Therefore, dry matter content was little influence on total taste. On the other hand, soluble sugar in steamed root showed a significant effect on taste of purple sweetpotato, in which soluble sugar content had a highly significantpositive correlationwithsweetness,viscosity and texture. Furthermore, non-reducing sugar content had more contribution to sweetness, fragrance, and texture than reducing sugar content, and the contribution to taste incremental from non-reducing sugar was 2.3 times than that of the reducing sugar content. Sweetnessoccupiedan extremely important positionin the taste evaluation ofpurple sweetpotato, and its contributionrate of taste increment was up to 55.38%.【Conclusion】The content of anthocyanin and soluble sugar in steamed root is an important index for edible purple-fleshed varieties.In conclusion, it should take into account both nutrition andfood quality in edible purple-fleshed breeding, and anthocyanin content should be controlledless than90 mg·100g^-1FW. The best way for traditional edible purple-fleshed sweetpotato breeding is to select purple-fleshed parent hybrid with high sugar-containing non-purple-fleshed parent.