ANALYSIS OF SAP SUGAR AND STARCH CONTENT OF FELLED OIL PALM TRUNKS AT DIFFERENT STORAGE TIME
Loading...
Date
2011-02
Authors
ABDUL HAMID, ZUBAIDAH AIMI
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
This research investigated the potential use of oil palm sap as a feedstock for
bioethanol production. Sap from squeezed oil palm trunks was investigated. The sugar
and starch content were further analyzed based on various cultivars, storage time, age
and location.
Four types of cultivars were used for the study that include; Dura x Pisifera
mix (Dura x URT) , Dumpy x Yangambi x AVROS, Deli Dura x Yangambi (D3D x
L236T) and Deli Dura x Pisifera x H&C. The felled oil palm trunks were stored at a
different duration of storage time; 0, 15, 30, 45, 60 and 75 days, before they were cut
into discs. The disc was divided into 3 parts: inner (A), middle (B), and peripheral (C)
parts, respectively. Each parts of the OPT was squeezed to obtain the fresh sap. High
Performance Liquid Chromatography (HPLC) and phenol sulphuric acid method were
used to determine the total sugar and individual sugar content of the sap. Starch in oil
palm samples was analyzed using the method by Humphrey and Kelly. The anatomy
structure of oil palm trunks was conducted through the Scanning Electronic Microscopy
(SEM) and taken from the transverse section. The physical properties of the sample;
moisture content and density, were investigated in accordance to American Society for
Testing and Materials (ASTM) standard.
Microscopic investigation result showed that oil palm trunks contain
abundant amount of starch especially in the upper part of oil palm tree. Based on the
finding of this study on physical prope11ies showed that moisture content for all cultivars
are from 147% to 1022% and gradually increased from inner to peripheral zone. In this
study, cultivar Deli Dura x Yangambi (D3D x L236T) was identified to contain highest
moisture among others samples. The density is higher from peripheral part and
progressively lower in the inner part. Cultivar Dumpy x Yangambi x AVROS has been
found to be the highest density among to the other cultivars.
Sugar analysis showed the amount of sugar in the oil palm sap
approximately more than 60% of the whole tree. Sugars exist in the sap and were found
to increase as the storage time extended after felling especially after 30 to 60 storage
days. The inner and middle parts (part A and B) were identified to contain highest total
sugar content with presence of three main sugars glucose, sucrose and fructose and
others sugars. Cultivar Dura x Pisifera mix (dura x URT) shows the highest total sugar
in the sap with the concentration from 43.82 to 18l.89 mg/ml obtained by HPLC and
38.94 to 18l.74 mg/ml obtained by Colometric method.
The starch content started to be high at the initial storage time and decreases
around day 30 to 60 of storage. The average amount of starch content was found about
0.8% and the highest starch content was found in the inner part (A) and middle part (B).
Cultivar Dumpy x Yangambi x AVROS was recognized to contain highest starch level
about 0.07% and 3.21% and Deli Dura x Yangambi (D3D x L236T) type contain lower
starch content, around 0.06% and 1.55% .
Investigation on relationship of moisture content and sugar content found
that higher moisture content will give lowest sugar content. Study on relationship of
sugar content and starch content also showed that degradation of starch content is
significant wi th the increases of the sugar content.
Oil palm trunks were indicated as a promising feedstock that is suitable for
the production of bioethanol with the appropriate storage time and type of cultivar. In
this study, cultivars Dumpy x Yangambi x AVROS was found to be the most potential
cultivar to be used to achieve this target.
Description
Keywords
SAP SUGAR , STARCH CONTENT