Department of Chemistry and Material Science, Faculty of Experimental Science, University of Huelva, 21007, Huelva, Spain.
Rapid Commun Mass Spectrom. 2012 Apr 15;26(7):835-44. doi: 10.1002/rcm.6155.
Iberian ham is a product of high commercial value whose quality mainly depends on breeding and feeding of pigs in an authorized way. Simple, fast, simple, reliable and high-throughput analytical methods are necessary to assure the quality of ham and for fraud prevention. Tandem mass spectrometry (MS/MS) is proposed as an advantageous alternative over other analytical techniques commonly used in this industry for product authentication.
The analytical approach is based on direct infusion electrospray mass spectrometry (ESI(+)-MS) of dichloromethane/methanol (60:40) extracts of ham intramuscular fat. Similarly, atmospheric pressure photoionization ionization mass spectrometry (APPI(+)-MS) was used with a flow injection analysis system for sample introduction with methanol/water (50%) as the mobile phase and toluene as the dopant. All experiments were performed on an API QSTAR® XL Hybrid system using both ESI and APPI sources.
The ESI(+)-MS mass spectra present several clusters of peaks attributed to ammonium adducts [M + NH(4) (+) ] of lipid compounds (mono-, di- and triacylglycerols - MGs, DGs, TGs, and free fatty acids - FFAs), that can be identified by MS/MS spectra. On the other hand, the APPI(+)-MS spectra present [M + H(+) ] ions and reflect a higher fragmentation of the sample. Five different types of Iberian ham samples were successfully classified using partial least-squares discriminant analysis (PLS-DA) of data from these samples.
The application of direct infusion tandem mass spectrometry to dichloromethane/methanol extracts from intramuscular fat ham allows the simple, fast and reliable fingerprinting typification of different Iberian ham samples from pigs with different diets. With the proposed method, sample handling is minimal and chromatographic separation is not necessary, which represents an evident advantage over other analytical procedures usually used for this purpose.
伊比利亚火腿是一种具有高商业价值的产品，其质量主要取决于以授权方式饲养和喂养的猪。简单、快速、简单、可靠和高通量的分析方法对于保证火腿的质量和防止欺诈是必要的。串联质谱（MS/MS）被提议作为一种优于该行业中常用的其他分析技术的有利替代方法，用于产品认证。
该分析方法基于肌肉脂肪的二氯甲烷/甲醇（60:40）提取物的直接进样电喷雾质谱（ESI(+)-MS）。同样，大气压光致电离电离质谱（APPI(+)-MS）与流动注射分析系统一起使用，以甲醇/水（50%）作为流动相，甲苯作为掺杂剂进行样品引入。所有实验均在 API QSTAR®XL 混合系统上使用 ESI 和 APPI 源进行。
ESI(+)-MS 质谱呈现出几个峰簇，归因于脂质化合物（单、二和三酰基甘油 - MGs、DG、TG 和游离脂肪酸 - FFA）的铵加合物 [M + NH(4) (+) ]，可以通过 MS/MS 光谱进行识别。另一方面，APPI(+)-MS 光谱呈现出 [M + H(+) ]离子，反映出样品的更高片段化。使用来自这些样品的数据的偏最小二乘判别分析（PLS-DA）成功地对五种不同类型的伊比利亚火腿样品进行了分类。
直接进样串联质谱在肌肉脂肪的二氯甲烷/甲醇提取物中的应用允许对不同饮食的猪的不同伊比利亚火腿样品进行简单、快速和可靠的指纹特征分析。与提议的方法相比，样品处理最小化，不需要色谱分离，这与通常用于此目的的其他分析程序相比具有明显的优势。
