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Abstract
In this study, the protease producing microorganisms were in the fermented pine apple rinds
which were the waste materials that easy to find in the markets. There are 3 mixtures of fermenting
formula which different in the ratio of pine apple rinds (g) and sugar (g) (1:3, 3:1 and 1:1). The protease
activity were after fermented for 30 days. When compared the protease activity from the 3 mixtures the
results showed that 1:3 had a highest protease activity 28.39 unit/ml. Then selected the microorganisms
from fermented juice which had the highest protease activity were isolated and used as the starter to
ferment with sterilized pine apple rinds. The result demonstrated that mixture 3:1 added with N31-1
was 1.37 fold more protease activity (19.57 Unit/ml) than no starter fermentation (14.25 Unit/ml), 1:1
added with M11-2 had nearly the same protease activity (18.53 Unit/ml) as no starter fermentation
(17.6 Unit/ml). But 1:3 added with N13-2 had less protease activity (20.45 Unit/ml) than no starter
fermentation (28.39 Unit/ml) 0.72 folds. Furthermore, protease from fermented pineapple rinds juice had
optimum activity at temperature 50 °C and pH 7.0. This protease shown to be stable at alkaline
pH range and still active unless temperature was up to 60 °C.
Keywords :
Protease; Pine apple rinds fermented juice
