演題概要

1P-36

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MALDI-TOF MSを用いたA1/A2ミルクの識別～トリプシン消化法の最適化～

(¹島津・ ²Shimadzu Scientific Instruments・ ³Consolidated Lab Services)
^o山口久美子¹・ Thirukumaran, Milaan²・ Yanchik-Slade, Francine²・ Christensen, Daniel³・ 西風隆司¹・ Boutaghou, Mohamed²

The milk market has seen various changes over time, about 20 years ago A2-only cow milk was introduced into the market as an alternative to traditional cow milk (mixed A1/A2). A2-only cow milk claims better digestibility and lower risk of other ailments while keeping the same nutrition facts as mixed A1/A2 cow milk. The terms ‘A1’ and ‘A2’ refer to the variant of β-casein that is present in cow milk. A1 and A2 β-casein vary by a single amino acid at position 67. The current standard practice for determining if a cow will produce A2-only milk or mixed A1/A2 milk is through a genetic test to determine which alleles the cow carries. This can be a long and expensive process to have a full understanding of the genetic makeup of the herd. In this study, we suggest that the use of trypsin digestion combined with MALDI-TOF-MS can be used to provide a fast method of determining which β-casein is present in the final product.