A study has been conducted on the potential of hydrolysate protein from Etawa goat milk protein which is hydrolysed by bromelain crude extract enzyme. The bromelain enzyme is extracted from the leaf of honey pineapple fruit. The research steps are: bromelain extraction, bromelain characterization, preparation of goat milk protein, hydrolysis of goat milk protein with bromelain and antibacterial activity test of protein hydrolysate fractions against Escherichia coli and Staphylococcus aureus bacteria by diffusion method. The bromelain crude extract enzyme has the following characteristics: optimum pH is 6, optimum temperature is 55 °C, activity is inhibited by EDTA metal chelating compound and Cu²⁺ and Zn²⁺ metal ions, whereas Ca²⁺ and Mg²⁺ metal ions increase activity. Inhibition of activity by EDTA shows that the bromelain enzyme is a metalloenzyme. Ca²⁺ and Mg²⁺ metal ions act as activators, while Cu²⁺ and Zn²⁺ metal ions are inhibitors. Protein preparation of goat milk produces two types of protein namely casein and whey. The result of hydrolysis of both protein types with characterized bromelain enzymes are hydrolysate proteins, which are then tested for their antibacterial activity. The results showed that the hydrolysate protein was able to inhibit the growth of Escherichia coli and Staphylococcus aureus bacteria.

http://doi.org/10.1088/1757-899X/509/1/012111