Characterization of the milk-clotting properties of extracts from artichoke (Cynara scolymus, L.) flowers

Extract of artichoke (Cynara scolymus  , L.) flowers have been investigated as a source of enzymes to be used in cheese making as an alternative or in addition to calf rennet. Coagulation activity was highly dependent upon milk pH and temperature. The rennet strength (RS) of this extract increased hyperbolically with increasing concentrations of calcium, and the concentration was saturated at 50mm. However, the effect of sodium chloride on RS was not significant. Additionally, the properties of individual cynarases obtained from artichoke flowers were also studied. Purification led to a decrease in the specific coagulant activity relative to that of the crude extract in the case of cynarases A and C, whereas cynarase B increased its specific clotting activity. Moreover, whereas the cynarases A and C showed a slight increase in specific peptidase activity relative to the initial extract, the specific peptidase activity of cynarase B was much higher.