注水肉糜的低场核磁弛豫特性及判别分析

LF-NMR Relaxation Characteristics and Discriminant Analysis of Water-injected Ground Meat

摘要:

在对不同注水比例肉糜的低场核磁弛豫特性系统分析的基础上，进一步探索了肉糜注水程度定性、定量判别的可行性。结果发现：肉糜注水后，弛豫特性发生显著改变；随注水比例的增大，T2w呈线性增加（R2＝0.9118）；T22、T22m在注入比例为2% ~ 14%、16% ~ 30%、32% ~ 40%内呈阶梯型增大，且各范围间T22、T22m差异显著（p＜0.05）；S22相对增大，S23相对减小。LF-NMR结合判别分析发现，相同注水程度肉糜相对集中，不同注水程度（原料肉、轻度、中度、重度注水肉）组质心差别明显。注水程度分组正确率、交叉验证正确率分别为85.70% ~ 100%、81.00% ~ 100%。研究表明，可借助LF-NMR的T2w对肉糜注水比例进行有效预测，亦可通过多组分弛豫特性结合判别分析实现对肉糜注水程度的判别。

Abstract:

The low-field nuclear magnetic resonance (LF-NMR) relaxation characteristics of ground meat samples injected with different proportions of water were systemically evaluated in this study, and the feasibility of qualitative and quantitative discrimination analysis for examining the extent of water injection was explored. The results showed that injecting water into meat significantly changed the relaxation properties. With an increasing proportion of injected water, the T2w value was increased linearly (R2 = 0.9118), while T22 and T22m showed a stepped increase with increasing proportion of injected water, in the ranges of 2~14%, 16~0%, and 32~40%, respectively. T22 and T22m showed significant differences in all ranges (p<0.05). The values of T22 and S22 were increased, while that of S23 was decreased. LF-NMR combined with discriminant analysis showed that the samples with the same proportion of injected water were clustered, and significant differences were found in the group centroids among the samples with different proportions of injected water (raw meat and meat with small, medium, and large proportions of injected water). The rates of correct grouping based on the extent of water injection, and the rates of cross-validation accuracy were 85.70~100% and 81.00~100%, respectively. The results indicate that the proportion of injected water can be effectively predicted using T2w in LF-NMR, as well as by discriminant analysis combined with the multicomponent LF-NMR relaxation properties of the samples.