To extract pectin in food industry, HCl is generally used as the major extracting solvent for releasing the pectin from the plant tissues, however it has an environmental issue to use. In this study, food-grade tartaric-, malic, and citric acids were used to produce apple peel pectin as an eco-friendly protocol instead of HCl. Finely-ground lyophilized apple peel was applied as the raw material, and the pectin was extracted by organic acids at 85 °C. The pectin extracted with citric acid displayed greater molecular weight and apparent viscosity compared to other organic acid treatments. Analysis of degree of methyl esterification revealed that the pectins extracted with organic acids were highly methoxylated. From these results, it was suggested that organic acids could be utilized to extract apple peel pectin effectively as a green process. Especially, the extraction process with citric acid as the solvent showed great potential to produce high-viscosity apple peel pectin.
Bibliographical noteFunding Information:
This research was supported by High Value-added Food Technology Development Program (# 315063-3 ) of IPET (Korea Institute of Planning & Evaluation for Technology in Food, Agricultural, Forestry and Fisheries) in Ministry for Food, Agriculture, Forestry and Fisheries (MAFRA), Republic of Korea.
© 2018 Elsevier Ltd
- Apple peel waste
- Green process
- Molecular mass
- Organic acids
- Pectin extraction