Proximate Composition
After it was cut into a uniform size, the sample was then
analyzed for moisture, protein, fat, ash, crude fiber by the
AOAC method [12] and carbohydrate was calculated as:
% carbohydrate =
100 – (% moisture + % protein
C.Dilute-acid Hydrolysis
The 10% (w/v) of durian peel was hydrolyzed in autoclave
at 121 °C, 15-60 min at 0.5 - 2 % (v/v) of HCl. The
hydrolysis sample was centrifuged at 3,000 rpm for 20 min.
D. Analysis of Hydrolysate
The solid fraction was washed with distilled water and
dried in a hot oven at 70°C until the constant weight was
obtained. Then the percentage of weight determination for
acid hydrolysis efficiency (AHE) was calculated using the
following equation (2). The supernatant was collected and
determined for reducing sugar using 3,5-dinitrosalicylic acid
[13] and total sugar using phenol sulfuric acid [14]. The
Matura Unhasirikul, Nuanphan Naranong, Woatthichai Narkrugsa
Reducing Sugar Production from Durian Peel
by Hydrochloric Acid Hydrolysis
A
+ %fat + %fiber + %ash)