Preliminary Studies on the Gelation Processes of Fermented and GDL‐acidified Bovine and Caprine Milk Systems

Bovine and caprine milk gels were made by GDL‐acidification and yogurt fermentation (using ‘ropy’ and ‘non‐ropy’ starter cultures). The respective gelation processes were monitored rheologically using dynamic oscillatory testing. The bovine fermented systems produced gel structures with about half the strength of the equivalent chemically acidified gels. The fermented caprine milk systems produced gel structures some eight to 10 times weaker than the equivalent acidified systems. In all cases the caprine systems were weaker than the bovine gels despite having higher protein contents. In all cases the ‘ropy’ milk systems followed somewhat different gelation patterns and formed weaker gels than the equivalent ‘non‐ropy’ and GDL‐acidified systems. These data suggested that the starter culture material (biomass and extracellular polysaccharides) may have interfered with the protein–protein interactions during yogurt fermentation. This produced weaker gel structures, possibly by a modified gelation mechanism.