Pengaruh Variasi Konsentrasi Sodium Klorida terhadap Hidrolisis Protein Ikan Lemuru (Sardinella lemuru Bleeker, 1853) oleh Protease Ekstrak Nanas (Ananas comosus [L.] Merr. var. Dulcis)

Abstract

The research about the effects of variation of sodium chloride (NaCl) concentration on the hydrolysis product of lemuru fish protein (Sardinella lemuru Bleeker, 1853) by use pineapple (Ananas comosus [L.] Merr. variety of Dulcis) extract protease has been carried out. The aims of this research were to evaluate the effects of variation of NaCl concentration on the soluble protein contents, protein cleavage characteristics, and the degree of hydrolysis (DH) on protein hydrolysate of lemuru fish. Fish protein hydrolysate obtained by hydrolysis reaction of lemuru fish slurry protein by pineapple extract protease at incubation temperature of 37oC for five days. Soluble protein contents determined based on Formol Titration method, while cleavage characteristics evaluate based on application of SDS-PAGE electrophoresis. Degree of hydrolysis of fish protein hydrolysate estimated by TNBS method. The variation of NaCl concentration were 0.0%, 5.0%, 10.0%, 15.0%, and 20.0% w/w resulted in soluble protein content were 2.98%, 3.23%, 3.39%, 4.23%, and 3.40%, respectively; whereas the value of degree of hydrolysis (DH) reach for 4.13%, 5.37%, 6.52%, 33.48%, and 24.09%, respectively. Pineapple extract protease causes hydrolysis of slurry protein of lemuru fish at all variation of NaCl concentration. It is supported by electrophoretogram which not provide of protein bands at molecular weight over 14.2 x 103 Da. Maximum hydrolysis process occured on NaCl concentration of 15.0% w/w with soluble protein content and degree of hydrolysis (DH) optimum. This phenomena indicating the same trend between soluble protein content and degree of hydrolysis.