Determination of Residues of 26 β2-Agonists in Pork Liver by Reversed Phase High Performance Liquid Chromatography-Tandem Mass Spectrometry / 分析化学

A method for determination of residues of 26 β2-agonists in pork liver was developed using high performance liquid chromatography with tandem mass spectrometric ( HPLC-MS/MS ) . After enzymatic hydrolysis with β-Glucuronidase/Arylsulfatase for 12 hours, the pH of sample solution was adjusted to 1 using perchloric acid for protein precipitation. The precipitate was extracted with 0. 1mol/L perchloric acid aqueous. The extracts in the above two steps were combined and adjusted to pH 4 for the solid phase extraction ( MCX) . And then the 26 β2-agonists residues in the extracts were separated on a reversed phase HPLC column using a gradient elution program of 0. 1% formic acid aqueous solution (A) and 0. 1% formic acid in acetonitrile solution ( B) . Multiple reaction monitoring ( MRM) with positive polarity was selected to monitor qualitative and quantitative ion. Based on the optimized method, 26 β2-agonists could be analyzed in 15 min. The recoveries ranged from 64 . 0% to 112 . 7% for the 26 kinds ofβ2-agonists residues with three spiked levels of 5, 10 and 20 μg/kg. The relative standard deviations ( RSDs) were less than 15. 2%. The limits of detection (LOD) for the 26 kinds of β2-agonists were 0. 15-1. 35 μg/kg.

The Study on Acceptability of Liver Sausage by Proportions of Liver and Processings

Objectives of this study were to investigate the acceptability of liver sausages, one of the most favorite product of meats, and to examine the applicability of pork liver in manufacturing sausages. Sausages containing different proportions of pork liver were manufactured with various processes and were tested and analysed by means of sensory evaluation. Based on th basic recipe for manufacturing sausages, fifteen recipies were proposed with different combinations of ingredients, followed by evaluations on their physicochemical and nutritional properties. Sausages manufactured with different methods (sliceable, spreadable, smoked spreadable) and different proportions of liver were also evaluated. The Findings from these experiments are summarized as follows: 1. As the percentage of the liver was incresed, outer color of experimental sausages were significantly decreased. 2. The hardness, gumminess, chewiness were significantly decreased as the amount of liver increased. 3. Sausages containing 30% pork liver had best acceptability after swallowing. 4. The flavor and taste of liver in experimental sausages were significantly increased by adding liver. In summary, sausages containing 30% pork liver had best acceptability for consumption in terms of the indices measured in this study.