Cocoa waste may become valuable source of pectin, suggest researchers

Cacao pod husks – a major by-product of cocoa processing – could provide industry with a new, environmentally friendly source of pectin, say researchers.

Writing in LWT - Food Science and Technology a team of Brazilian researchers suggest that cacao husk waste from the production of cocoa could be used to extract pectin using citric acid.

The utilisation of such waste – which accounts for as much as 76% of cacao fruit by weight – for the extraction of value added ingredients such as pectin would help to improve waste disposal. The team, led by Lúcia Cristina Vriesmann of the Universidade Federal do Paraná, Brazil, investigated the main parameters influencing pectin yield from cocoa husks – finding that yield depends on extraction conditions, including time, pH, and temperature.

The authors revealed that an average of 10 grams of pectin could be extracted from every 100 grams of husk by-product. When put into the perspective that each ton of dry cocoa bean produces ten tonnes of cacao pod husk waste, then the ability produce pectin and at the same time manage waste levels could be attractive for the industry.

Estimates of cocoa husk waste based on this are around 40 million tonnes per year, with the burden continuing to increase – and representing a serious challenge for waste management, said Vriesmann and his team.

“In cocoa producer countries, the processing of this cacao waste may offer economic advantages and decrease the extent of the associated environmental problems,” they added.

“Extraction of pectins from the main by-product of cocoa production would not only help to reduce the costs of the production of cocoa products but would also manage the disposal of this waste in an environmental friendly manner through the use of a natural and safe food additive.”

Study details

Vriesmann and colleagues examined the variables that influence the extraction of pectins from cacao pod husk using citric acid.

“From the fitted model, extraction conditions with aqueous citric acid at pH 3.0 for 95 minutes at 95°C provided a predicted yield of approximately 9.0 g/100g dry cacao pod husks.”

“The increasing industrial demand for pectins with varying ability to gel or stabilize products increases the need for pectins of different types or derivatives with tailored properties.”

Source: LWT - Food Science and Technology

Published online ahead of print, doi: 10.1016/j.lwt.2012.04.018

“Extraction and characterization of pectin from cacao pod husks (Theobroma cacao L.) with citric acid”

Authors: L.C. Vriesmann, R.F. Teófilo, C.L. de Oliveira Petkowicz