不同品种萝卜品质及挥发性物质研究

Study on quality and volatile substances of different varieties of Raphanus sativus L.

目的探究不同品种萝卜理化品质及挥发性物质间的差异。方法采用生理生化测定方法和气相色谱-离子迁移谱法(gas chromatography-ion mobility spectrometry,GC-IMS)对6个品种萝卜的营养成分及挥发性组分进行检测,并建立综合评价萝卜品质的评价模型。结果“青峰”含水量最高,为94.61%;“心里美”的可溶性固形物(6.50%)、可溶性糖(3.17%)、可滴定酸(0.12%)、维生素C(22.67 mg/100 g)含量均最高;采用GC-IMS共定性出45种挥发性物质,其中醛类、酯类、酮类是萝卜特征性香气的主要成分,利用偏最小二乘判别分析法(partial least square-discriminant analysis,PLS-DA)共筛选出10种标志挥发性物质。建立综合评价模型,其中“水果萝卜”“心里美”的综合得分较高,均在1以上,综合评价效果较好。结论结合营养成分和挥发性成分进行综合评价,筛选出在宁南山区适应性良好的品种有“水果萝卜”“心里美”,可考虑作为新品种选育及定向育种的优良品种。经聚类分析,为6个品种萝卜后续开发利用提供了方向。

Objective To explore the differences in physicochemical quality and volatile substances of different varieties of Raphanus sativus L..Methods The nutritional components and volatile components of 6 varieties of Raphanus sativus L.were detected by physiological and biochemical methods and gas chromatography-ion mobility spectrometry(GC-IMS),and the calculation equation for comprehensive evaluation of Raphanus sativus L.quality was established.Results The water content of‘Qingfeng’was the highest(94.61%).The content of soluble solids(6.50%),soluble sugar(3.17%),titratable acid(0.12%)and vitamin C(22.67 mg/100 g)in‘Xinlimei’were the highest.A total of 45 volatile substances were identified by GC-IMS,among which aldehydes,esters and ketones were the main components of the characteristic aroma of Raphanus sativus L..A total of 10 marker volatile substances were screened by partial least square-discriminant analysis(PLS-DA).The calculation equation of comprehensive evaluation was established,in which the comprehensive scores of‘Fruit Radish’and‘Heart Beauty’were higher,all above 1,and the comprehensive evaluation effect was better.Conclusion Combining the comprehensive evaluation of nutritional components and volatile components,‘Fruit Radish’and‘Xinlimei’with good adaptability in the mountainous area of southern Ningxia have been screened out,which can be considered as excellent varieties for new variety breeding and directional breeding.The cluster analysis provides a direction for the subsequent development and utilization of 6 kinds of Raphanus sativus L..