Physico-chemical characterization of a milk-clotting fraction extracted from turkey (Meleagris gallopavo) proventriculus. (August 2018)

• Record Type: Journal Article
• Authors: Mekhaneg, B.; Girardet, J.-M.; Humbert, G.; Saulnier, F.; Poirson, C.; Bellal, M.-M.
• Is Part Of: Innovative food science & emerging technologies. Volume 48(2018)
• Page Start: 172
• Page End: 178
• Publication Date: 2018-08
• Subjects: Clotting activity -- Meleagris gallopavo -- Pepsin-like -- Proventriculus -- Turkey; Food -- Biotechnology -- Periodicals; Food industry and trade -- Technological innovations -- Periodicals; Aliments -- Biotechnologie -- Périodiques; Food -- Biotechnology; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.ifset.2018.06.006
• Languages: English
• ISSNs: 1466-8564

Abstract

Abstract: Valorization of avian by-products such as turkey ( Meleagris gallopavo ) proventriculus in the preparation of milk clotting enzymes constitutes an alternative to commercial rennet. The clotting enzyme of Meleagris gallopavo has been prepared by ammonium sulfate at 50% saturation followed by purification by cation-exchange fast protein liquid chromatography (FPLC), and determination of the clotting protease activity performed on milk incubated at 35 °C. The clotting fractions are concentrated and dialyzed against Tris/HCl pH 7.0 through a membrane with cutoff 8000 Da, and separated by anion-exchange FPLC. The coagulating fractions obtained by cation-exchange chromatography are also separated by reversed-phase high-performance liquid chromatography, which revealed only one fraction able to coagulate milk. Electrophoresis analysis revealed a band with apparent molecular mass of 36.5 kDa and seemed to correspond to pepsin-like enzyme according to primary sequence alignment analyses. Maximal clotting activity was obtained for optimal conditions of temperature of 55 °C and pH 5.4. Highlights: An enzyme fraction from turkey proventriculus was purified by chromatography FPLC and HPLC. The proventriculus turkey enzyme displayed a milk-clotting activity. The turkey enzyme is a pepsin-like enzyme of 36.5 kDa according to sequence alignments. The turkey enzyme can advantageously replace calf rennet.