Pectin grading weight

Christensen, P.E. 1953. Methods of grading pectin in relation to the molecular weight (Intrinsic Viscosity) of pectin, Pectin Symposium of the New York Preservers Association, pp. 163-172. 

Citrus pectin (MexPec 1400) with the molecular weight (M.W.) of 1.8 x 105 dalton and the degree of esterification of 82 and Nisaplin (2.5% Nisin) were purchased from Danisco-Cultor (Kansas City, KS). Soybean flour protein (SFP), poly(ethylene oxide) (PEO, M.W. 900,000), and glycerol (reagent grade, < 99.5%) were obtained from Aldrich Chemical Corp. (Milwaukee, WI). 

Figure 1 shows the relationship between grade measured by elastic deformation (grade is 65, the per cent of soluble solids, divided by concentration of pectin in per cent) and number average molecular weight (Af ). All of the points fall on a smooth curve similar to that found for fibers of cellulose derivatives (28) when their physical properties are determined as a function of Mn. 

Materials-. PVC pellets, extrusion medical-grade RB1/T3M of 1.25 g cm density, were obtained from ModerrPlast (Italy) and used as received. Pectin from apple, (BioChemika, with esterification of 70-75%), acrylic acid (AA) (99.0%, anhydrons), and V-(3-dimethyl aminopropyl)-V -ethyl carbodiimide hydrochloride (EDAC, 98.0%) were supplied by Fluka (USA). Chitosan from crab shells with meditun molecttlar weight and deacetylation degree of 75-85%. 

Three different varieties of Papaya peels (Cor/co papaya L.) were analyzed as a source of pectin wild variety, a domesticated variety, and the "Solo" variety [43]. Papaya peels are discarded into the environment, causing organic pollution. Sometimes it is used as animal feed, not receiving any treatment or use. The results indicated that pectins of both varieties had a low grade of esterification and high molecular weight Although pectins were characterized structurally, functionality studies are needed in order to consider their optimal application within food systems. 

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