烤烟上部烟叶中非挥发性有机酸及高级脂肪酸与烟叶内在品质的关系

Relationships between non-volatile organic acids,higher fatty acids and intrinsic quality of upper flue-cured tobacco leaves

为明确非挥发性有机酸、高级脂肪酸在上部烟叶原料品质评价中的作用,采用气相色谱-质谱联用仪对我国12个省(直辖市)27个产烟市的111份B2F等级烟叶样品进行检测,结合多元统计方法,分析了不同种植区域上部烟叶非挥发性有机酸和高级脂肪酸含量的差异及其与烟叶常规化学成分、感官评价指标之间的关系,并采用积分球漫反射技术建立了近红外速测模型。结果表明:①不同种植区域上部烟叶中非挥发性有机酸和高级脂肪酸含量的差异及分布规律均不一致。②棕榈酸含量与常规化学成分关系密切,与总糖和还原糖的相关性较高,相关系数分别为0.6507和0.6414。③棕榈酸含量对10项感官评价指标均有显著影响,苹果酸含量主要影响细腻感、清晰度、香气量、杂气和评价总分,富马酸含量主要影响细腻感、清晰度、余味和评价总分。棕榈酸含量大于3.00 mg/g、苹果酸含量小于等于65.00 mg/g、富马酸含量大于0.07 mg/g时,烟叶感官评价得分显著提高。④在所建近红外速测模型中,棕榈酸、苹果酸和富马酸含量的校正模型及交叉验证模型的相关系数均在89%以上。通过所建近红外速测模型可以快速检测上部烟叶中棕榈酸、苹果酸和富马酸的含量。棕榈酸、苹果酸和富马酸可以作为上部烟叶原料质量的重要评价指标。

To clarify the roles of non-volatile organic acids and higher fatty acids in the quality evaluation of upper leaves of flue-cured tobacco,111 samples of grade B2F from 27 tobacco planting regions in 12 provinces of China were measured by gas chromatography-mass spectrometry.The differences in the contents of non-volatile organic acids and higher fatty acids in the leaf samples and their relationships with the routine chemical indexes as well as sensory quality were analyzed with multivariate statistical methods.The near-infrared rapid measurement models were established by the integrating-sphere diffuse-reflection technique.The results showed that:1)Both the contents and distribution patterns of the measured non-volatile organic acids and higher fatty acids in the tested upper flue-cured leaf samples were different.2)Palmitic acid content was closely correlated to the routine chemical indexes,and there was a high correlation between palmitic acid content and the contents of total sugar and reducing sugar,with correlation coefficients of 0.6507 and 0.6414 respectively.3)Palmitic acid had significant effects on 10 sensory evaluation indexes,malic acid mainly affected the smoothness,clarity,aroma quantity,offensive odor and total sensory score,and fumaric acid mainly affected smoothness,clarity,aftertaste and total sensory score.The sensory scores of tobacco leaves with palmitic acid content higher than 3.00 mg/g,malic acid content less than or equal to 65.00 mg/g,and fumaric acid content higher than 0.07 mg/g were significantly higher.4)The correlation coefficients of the near-infrared-corrected and cross-validated models for palmitic acid,malic acid,and fumaric acid were above 89%.These models could be used to rapidly detect the palmitic acid,malic acid,and fumaric acid contents in upper flue-cured leaves.In conclusion,palmitic acid,malic acid,and fumaric acid could be used as important quality evaluation indexes for upper flue-cured tobacco leaves.