# Turning Agricultural Waste Into Enzymatic Treasure: Bromelain Stability in Pineapple Crown and Peel Waste From Subang District, Indonesia

## TL;DR

This study shows pineapple crown and peel waste can be stored to preserve bromelain, a useful enzyme, for up to 20 days under specific conditions.

## Contribution

The study identifies optimal storage conditions for preserving bromelain in pineapple crown and peel waste.

## Key findings

- Pineapple crown and peel waste can be stored for 7 days at 29 ± 1°C and 20 days at 4 ± 0.5°C.
- Crown bromelain had higher protease activity compared to peel bromelain.
- Pineapple crown waste shows potential as a bromelain source.

## Abstract

Bromelain is one of the protease enzymes found in all parts of pineapple (Ananas comosus (L.) Merr.), including the crown and peel. This enzyme has been widely used in various fields of life, including the food industry, health, pharmaceuticals, and cosmetics. However, pineapple processing often focuses on the flesh of the fruit, leaving behind substantial agricultural waste, such as crown and peel waste. The waste is often collected and stored before being used, causing the bromelain enzyme to decrease or even dissipate. Therefore, this study aims to determine the effect of time and the condition of storage of pineapple crown and peel waste on total protein content and protease activity. The extracted bromelain was precipitated with ethanol and then dried, and total protein content and protease activity were determined. The results showed that pineapple crown and peel waste can be stored for 7 days at 29 ± 1°C and humidity of 70 ± 2% and 20 days at 4 ± 0.5°C and humidity of 40 ± 2%, respectively. The total protein content and protease activity were 169.94 ± 2.68 μg/mL and 46.35 ± 0.69 IU/mg for crown bromelain, while those for peel bromelain were 229.75 ± 15.61 μg/mL and 29.10 ± 1.98 IU/mg, respectively. In conclusion, pineapple crown waste has the potential to be developed as a source of bromelain.