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III. RESEARCH METHODOLOGY
A. Materials and Instruments
1. Materials
Main ingredient that used in this research was sugar palm seed Arenga westerhoutii Griff. that stored under -20
o
C. Chemical that used in the extraction of pectin were HCl 0.25 N, distilled water, and ethanol 95. Chemical that used in the characterization of extracted pectin were ethanol 95, NaCl,
NaOH 0.25 N, NaOH 0.1 N, phenol red indicator, sulphuric acid 98, carbazol solution, HCl 0.25 N, phenolphtalein, methyl red.
2. Instruments
Instruments that used in this research were blender, pH meter, microwave oven, cheesecloth, vacuum evaporator, Whatman 41 paper, oven, buret, electric furnace, crucible, dessicator, burner,
spectrophotometer, beaker glass, flask, volumetric pippet, and viscometer
.
B. Experimental Design
This research was divided into two parts. The first part was extraction of pectin from raw material young endosperm of sugar palm seed using microwave-assisted extraction. The second parts were
characterization of pectin including determination of moisture content, ash content, equivalent weight, galacturonic acid content, degree of esterification, and comparison of extracted pectin to commercial
pectin.
1. Extraction of pectin
Extraction of pectin conducted in order to get pectin for characterization and to determine the combination effect of microwave power and extraction time on the resulting pectin. The stages on pectin
production consist of:
a. Sample preparation
Sugar palm seed that stored under -20
o
C was thawed using running water. This process usually took time around 2 hours until the ice was completely gone.
b. Extraction
Sugar palm seed was weighed and crushed using blender for 2 min with addition 600 mL of distilled water. Adjustment of pH was done by adding hydrochloride acid 0.25 N until pH
reaches 1.5. Extraction was performed on microwave oven with microwave power and time varies as treatments.
Microwave power used in this study was 600 W and 800 W. While the extraction time used in this study was 3 min, 5 min, and 7 min. Extracted solution was filtered by using a thick
cheesecloth and was squeezed to separate the filtrate from the pulp. Then the solution was concentrated on rotary evaporator until the volume became half of its original volume by heating
at 80
o
C.
c. Precipitation isolation
The evaporated filtrate was cooled in the room temperature then pectin precipitation was performed by adding 95 ethanol that had been acidified adding 2 mL concentrated
hydrochloride acid per one liter of ethanol. The ratio of filtrate with ethanol added is 1:1.5. Precipitation process was done for 12 hours. Pectin precipitate was filtered using Whatman 41
paper to separate the precipitated pectin from ethanol solution.
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d. Washing
Pectin sediment was washed by using 95 ethanol until the sediment was free from chloride. Separation of precipitated pectin with ethanol was done using thick filter cloth then squeezed.
Determination the presence of chloride was done by adding a few drops of a solution of silver nitrate AgNO
3
in the used washed solution. If chloride was still there, it will form a white precipitate AgCl.
e. Drying
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