Analytical Sciences Unit, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK.
Oxford Instruments Industrial Analysis, Tubney Woods, Abingdon, Oxfordshire OX13 5QX, UK.
Food Chem. 2015 May 15;175:1-9. doi: 10.1016/j.foodchem.2014.11.110. Epub 2014 Nov 26.
This work reports a candidate screening protocol to distinguish beef from horse meat based upon comparison of triglyceride signatures obtained by 60 MHz (1)H NMR spectroscopy. Using a simple chloroform-based extraction, we obtained classic low-field triglyceride spectra from typically a 10 min acquisition time. Peak integration was sufficient to differentiate samples of fresh beef (76 extractions) and horse (62 extractions) using Naïve Bayes classification. Principal component analysis gave a two-dimensional "authentic" beef region (p=0.001) against which further spectra could be compared. This model was challenged using a subset of 23 freeze-thawed training samples. The outcomes indicated that storing samples by freezing does not adversely affect the analysis. Of a further collection of extractions from previously unseen samples, 90/91 beef spectra were classified as authentic, and 16/16 horse spectra as non-authentic. We conclude that 60 MHz (1)H NMR represents a feasible high-throughput approach for screening raw meat.
本研究报告了一种基于 60MHz (1)H NMR 光谱比较甘油三酯特征来区分牛肉和马肉的候选筛选方案。通过简单的氯仿提取,我们在通常 10 分钟的采集时间内获得了典型的低场甘油三酯谱。使用朴素贝叶斯分类,峰积分足以区分新鲜牛肉(76 个提取物)和马肉(62 个提取物)样品。主成分分析给出了二维“真实”牛肉区域(p=0.001),可以进一步比较其他光谱。该模型使用 23 个冷冻-解冻训练样本的子集进行了挑战。结果表明,冷冻储存样品不会对分析产生不利影响。在进一步收集来自先前未见样本的提取物中,90/91 份牛肉光谱被分类为真实,16/16 份马肉光谱被分类为非真实。我们得出结论,60MHz (1)H NMR 代表一种可行的高通量筛选生肉的方法。