Extraction and characterization of pectin from waste of fruit peels

Abstract

In this study; pectin was extracted using traditional acid extraction method using fruit peel waste such as mandarin, pomegranate and pumpkin peels. The pectins obtained by using different fruit peels and changing the extraction conditions were characterized and compared with commercial pectin. Pectin extractions were carried out with varying parameters such as three different fruit peels as raw materials, two different acid types (citric acid and hydrochloric acid) for the extraction medium and two different extraction temperatures (80 degrees C and 90 degrees C). The effects of these parameters on the pectin yield and properties of pectin were investigated. Moisture and ash content, FTIR analysis, esterification degree, equivalent weight, methoxyl content and anhydrouronic acid content were determined for the characterisation of the extracted pectin samples. The pectin yields were found to be; 4.70-14.50% for mandarin peel, 4.40-9.25% for pomegranate peel and 2.10-4.80% for pumpkin peel. Among the fruit peels used in the study for pectin extraction, the highest pectin yield was obtained as 14.50% from the mandarin peel, which is a citrus fruit. The results of the analysis and characterization show that the samples are mainly composed of high methoxy pectins. Considering the yields of extracted pectins from different fruit peels, their properties and environmental effects, it was concluded that it is more appropriate to use citric acid as the extraction medium and to select the extraction temperature of 90 degrees C.