Comparison to Commercial Pectin

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e. Galacturonic content Rungrodnimitchaia 2011

5 mL of sulfuric acid 98 was added to 5 mL of 100 ppm of pectin solution. Then 200 μL of 0.1 vv carbazol solution was added to the sample. The sample was heated at 58-60 o C for 1 hour and cooled down to room temperature. The absorbance was measured at 525 nm against reagent blank. The total galacturonic acid unit content was derived from the calibration curve using standard solution of galacturonic acid at the same condition.

f. Degree of esterification Schultz 1965

Degree of esterification could be calculated by resulted methoxyl content and galacturonic content. Degree of Esterification = Methoxyl content x Galacturonic content x 3 x

g. Statistical analysis

Data were analyzed by one way ANOVA using the application of SPSS software. Mean value were compared using The Duncan’s Multiple Range Test.

C. Comparison to Commercial Pectin

First of all, the characteristic of low methoxyl commercial pectin was investigated. The parameters that were investigated were moisture content, ash content, equivalent weight, methoxyl content, galacturonic content, and degree of esterification. Then the value of each characteristic of extracted pectin and commercial pectin were considered and compared each other with standard value. 13

IV. RESULTS AND DISCUSSIONS

A. Extraction of Pectin

In this pectin extraction, two factors were used, which were microwave power and heating time. Microwave power used was 600 W and 800 W. Trial and error were done prior to the determination of these two values of microwave power. At trial and error, the use of microwave power above 800 W which was 1000 W resulted in overheating and very aqueous solution, so the solution could not be filtered using a cheesecloth. Therefore, this research was only used two power alone which was 600 W and 800 W. While another factor, heating time used was 3 minutes, 5 minutes, and 7 minutes. Various studies on the extraction of pectin by microwave heating was using the average time between 2-10 minutes. Therefore, this study used 3, 5, and 7 minutes for the range which was not too narrow and fairly evenly. In the first step of extraction, sugar palm seed was weighed and crushed using blender for 2 min by adding 600 mL of distilled water Figure 8a. Adjustment of pH was done by adding hydrochloride acid 0.25 N until pH reaches 1.5 Figure 8b. Extraction was performed on microwave oven with microwave power and time varies as treatments Figure 8c. After heating in the microwave, solution then filtrated using cheesecloth. The waste of this solution was separated and was not used for further step Figure 8d. The filtrate then concentrated using a rotary evaporator. Concentration process was done until the volume of solution became half of the initial volume Figure 8e. This was necessary because the ethanol would be able to precipitate the polysaccharide inside solution when the solution had a concentration over 80. Ethanol used also must have a concentration above 85. Therefore, this study used 95 ethanol solution, and the ratio between solution and ethanol was 1:2. The addition of ethanol could precipitate the polysaccharide inside solution because the ethanol would bind water so that the stability of the water- polysaccharide binding could be disrupted and polysaccharids eventually settled. After addition of ethanol, all types of polysaccharides inside solution would precipitate into fibrous-like clumps Figure 8f. The precipitate was then filtered, dried, and blended to produce a powdered polysaccharide Figure 8g. This powder contained various polysaccharide components such as pectin, starch, cellulose, and others. Extraction of pectin was conducted according to the flowchart on previous section. These are the documentation of pectin extraction. a Sugar palm seed blend with water b After adjustment pH into 1.5 c After microwave treatment d After filtration using cheesecloth