Sequential hydrolysis of swine carcass samples and determination of amino acid concentrations using pre-column derivatization with phenyl isothiocyanate

✍ Scribed by Wubben, Jennifer E; Albin, David M; Gabert, Vince M

• Book ID: 101226329
• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 110 KB
• Volume: 80
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/(sici)1097-0010(20000501)80:6<757::aid-jsfa621>3.0.co;2-z

✦ Synopsis

Comparing amino acid (AA) retention levels in pig carcass to true ileal digestible AA intake provides an estimate of the marginal ef®ciency of AA utilization. Accurate analysis of AA levels in the carcass samples is critical. However, the standard 24 h of hydrolysis does not always provide maximum AA values. A study was carried out to investigate the effect of hydrolysis time on AA measurements in pig carcass. Correction factors to standardize AA levels to 24 h of hydrolysis were also determined. Ground carcass samples were hydrolysed with 6 mol litre À1 hydrochloric acid (HCl) in a 110 °C oven for nine different time periods. Pre-column derivatization with phenyl isothiocyanate (PITC) was used to determine AA concentrations in all of the samples. Hydrolysis time signi®cantly affected (P `0.001) AA levels. The highest levels (P b 0.05) of valine, isoleucine, serine, glycine, threonine, alanine, arginine, proline, histidine and phenylalanine were not observed with 24 h hydrolysis. Therefore, correction factors and sequential hydrolysis curves are important for these amino acids. In conclusion, the effect of hydrolysis time should be considered in amino acids analysis.