Bromelain is distributed to all parts of pineapple (Ananas comusus (L.) Merr), including the peel, core, and crown, which are agricultural waste that has not been utilized properly.
Aims:

The purpose of this study was to determine the character and protease activity of crude bromelain from the Indonesian pineapple peel, core, and crown. The pineapple was collected from Subang district, West Java Province, Indonesia.
Methods and Material:

The three crude bromelains were obtained through the precipitation process with ethanol, then a protein qualitative and quantitative analysis was performed. Protease activity was determined by measuring the tyrosine produced from casein hydrolysis. The characters of crude bromelains were determined by evaluating the protease activity in various pH, temperature, and substrate concentration.
Statistical Analysis Used:

One-way analysis of variance was conducted to analyze the data statistically.
Results:

The three crude bromelains can be isolated from the peel, core, and crown of pineapple fruit with protease activity in the range of 38.32-46.78 units. Crude bromelains have an optimum temperature of 55°C for the peel and core and 35°C for the crown. All crude bromelains have an optimum pH of pH 7. The three crude bromelains have Vmax in the range of 140.85 to 285.71 units and KM in the range of 15298.59 to 18370.86 ppm.
Conclusions:

It concluded that the three crude bromelains have protease activity with the specific character and kinetic parameter.