DEGRADATION OF CASEINS FROM MILK OF DIFFERENT SPECIES BY EXTRACTS OF CENTAUREA-CALCITRAPA

Two purified aqueous extracts of Centaurea calcitrapa, a plant from th e Compositae family, were shown to degrade bovine, ovine, and caprine milk caseinates. The corresponding hydrolysis patterns were monitored by urea-polyacrylamide gel electrophoresis and compared with those of a commercial mixture of chymosin and pepsin. The plant proteases degra ded both alpha(s)- and beta-caseins more extensively than the commerci al rennet, thus yielding proteolytic patterns where different specific ities toward such substrates are apparent. The animal rennet was found to display the greatest clotting power per milligram of protein but t he least specificity toward ovine and caprine caseins. It is, therefor e, suggested that the said plant extracts be used as an alternative to commercial animal rennets especially in the manufacture of caprine an d ovine milk cheeses.