Determination of Pectin Yield and Their Characters of Some Local Apple Varieties in Kurdistan Region

Abstract

Pectin, a naturally occurring heteropolysaccharide, has in recent years gained increasingly in importance. The benefits of natural pectin are also more and more appreciated by scientists and consumer due to its biodegradability. Industrial pectins are extracted from by-products of the fruit juice industry apple pomace or citrus peels. They are extracted in acidic conditions and chemically modified to give High Methoxy (HM) pectins and Low Methoxy (LM) pectins. The properties of these two main types of differ widely. In this study, six variety of apple was selected as a representative of the apple fruit family to extract pectin. After removing seeds, the sliced pieces were dried at 65◦C for about 20hrs until the weight of samples become constant. Then the dry apple samples were crushed by an electric grinded. The grinder apple was sieved to remove the uncrushed particles, in a sieve of 60 mesh 250um and stored at a temperature 6-10^◦C. Pectin was extracted from sieved apple samples of each sample (A-F), the extraction was performed by using 500ml of hot deionized water which was acidified with 1N hydrochloric acid to pH value 1.8. 45ml of acidified water solvent was added to 1.5g of dry apple powder in conical flask and stirred for about 2 min until the homogenize mixture was appeared. Then the conical flask was transferred to the hot water bath and heated to 90^◦C for 2hrs with continuous stirring for 30min. The pectin yield and its equivalent weight, methoxyl contents, anhydrouronic acid (AUA) and degree of esterification (DE) of extracted pectin of each apple fruit samples (A-F) were determined.