Comparison of the quality of yoghurt produced from milk containing A1 and A2 β-casein

Abstract

Abstract A2 milk, characterised by the presence of only the A2 β-casein genotype, has recently been of great interest due to its potential health benefits, which are the subject of intensive scientific research. From the dairy industry standpoint, it is crucial to ascertain its functional and technological attributes. The objective of this study was to compare two types of yoghurt (A1 and A2 yoghurts), produced respectively from cows’ milk containing exclusively β-casein (β-CN) A1 (A1/A1) or A2 (A2/A2) genotypes, in terms of basic chemical composition, protein profile, amino acid composition, antioxidant capacity, sensory quality, acidity, instrumental texture and colour profiles, as well as rheological characteristics. The obtained results indicate that the β-CN polymorphism had no significant impact on the basic chemical composition, acidity, DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) or colour properties of the yoghurts. Nonetheless, the β-CN genotype did affect the textural, rheological, and sensory qualities of the acidic gels, with A2 yoghurt yielding gels exhibiting higher hardness, gumminess, improved consistency and viscosity, and overall sensory quality compared to the corresponding A1 treatment. These results indicate that A2 milk serves as a good raw material for fermented milk production, warranting further investigation.