摘要:Increase in the density of protein matrices i n yoghurt samples conta ining 10 to 30% total milk sol ids was studied by scanning electron micros copy and was corr e lated with a decrease in syneresis. Casein particles which formed chains and clusters in the protein matrix were largest in the 10% total solids yoghurt and their dimensions were decreased as the total solids contents were increased. This observation was confirmed by transmission electron microscopy of thin sections. An attempt has been made to explain the discrepancy between results on syneresis obtained by a drainage and a centrifugation method applied to yoghur t samples made at pi! 3.85 and 4.5. The explanation is based on a difference in rigidity of t he yoghurts under study and in t he forces affecting t he protein matrix during tests for syneresis.
关键词:Casein particles; Centrifugation test; Drainage test; Milk gels; Milk solids; Protein matrix; Scanning electron microscopy; Syneresis; Yoghurt