Characterization of Caseinophosphopeptides (CPPS) produced from α and β-casein fractions using yoghurt cultures

The α-sand β-casein fractions were fractionated from whole casein obtained from cow milk. 10% dispersions of α and β casein were fermented using purified 1% Streptococcus thermophilus (ST) & Lactobacillus bulgaricus (LB) cultures separately. Conditions were optimized by varying lactose concentration. (2,3 & 4%) and incubation time (12-48h). Caseinophosphopeptides were isolated by adjusting pH at 4.6, in presence of ethanol and 1% CaCl₂. CPPs from α casein fermented with LB showed higher yield (8% at 12h), mineral binding (0.45mg/mg of CPPs) and solubilizing ability (12.2mg/mg of CPPs) compared to other types indicating more hydrophilic peptides which was confirmed by RP-HPLC analysis. SDS-PAGE of the CPPs revealed molecular weight ranging between 3000-6500Da. The study concluded that LB has higher proteolytic activity than ST and may be used in the cost effective production of CPPs.