Waste from pineapple processing could provide a range of value added ingredients for the food industry, including a new source of the enzyme bromelain, say researchers.
The study – published in the journal Food and Bioproducts Processing – reports that waste products from pineapple processing, including the peel and stem of plants, could provide a valuable source of expensive bromelain extract.
Bromelain is an enzyme that is usually extracted from the stems or juice of pineapples. It has been used commercially in the food industry, dietary supplements, and the cosmetics industry – where it is known for meat tenderising, brewing, baking, and for the production of protein hydrolysates, among other things.
“Because of this very wide range of applications, commercial bromelain is very expensive costing up to 2400 USD/kg. The objectives of this study were to extract bromelain from the pineapple wastes ... to investigate some biochemical characteristics of the extracts,” said the research team, led by Dr Saroat Rawdkuen of Mae Fah Luang University, Thailand.
Rawdkuen and his team found waste portions including the peel, core, stem and crown, contained high levels of the valuable enzyme. They reported that peel gave the highest yield of the enzyme (providing up to 40% by weight) whilst the crown provided enzymes with the highest protease activity.
The Thai research group isolated and characterised bromelain extracts from the wastes from fruits grown in Chiang Rai province (Nang Laeand Phu Lae pineapple cultivars).
Waste portions provided a significant yield of the enzyme with peel supplying between 29 and 40% by weight. Core, stem and crown waste products were found to yield 9–10%, 2–5% and 2–4% respectively.
Rawdkuen and his colleagues concluded that with increasing pineapple production – and thus proportionally increasing wastes – the process of bromelain extraction from such waste could provide “much added value.”
They added that the use of wastes in such a way would not only provide added revenue through increased bromelain supply, but would also reduce the impact of waste disposal – which “represents a growing problem since it is usually prone to microbial spoilage and it causes serious environmental problems.”
Source: Food and Bioproducts Processing
Published online ahead of print, doi: 10.1016/j.fbp.2011.12.006
“Pineapple wastes: A potential source for bromelain extraction”
Authors: S. Ketnawa, P. Chaiwut, S. Rawdkuen