Abstract:
Liquid glucose is an essential ingredient used in confectionery and other food preparation industries mainly to prevent crystallization of sugar and consequence hardening. Over 3, 000 Mt of liquid glucose are imported to Sri Lanka annually and it is cost about Rest. 100,000,000/=. The purpose of this study is to see the feasibility of the production of liquid glucose for cottage and medium scale industries by acid hydrolysis and reduce the importation cost.
In this study starch of cassava, which has bulk production in Sri Lanka is used as the
raw material. Hydrolysis of starch to glucose is achieved using hydrochloric acid.(Acid hydrolysis) After neutralization with sodium carbonate, the hydrolysis is decolorized, filtered and concentrated to obtain a product containing 80-85% total solids.
The starch samples were acidified with 2M, 4M and 6M of hydrochloric acid. The samples treated with one acid concentration were autoclaved at three different pressure levels 68.94x103 Nm'2, 103.41 x103 Nm'2 and 137.88x103 Nm'2 and the hydrolyzing time was measured at 120 °C. The TSS, Dextrose Equivalent, color,moisture content and ash content of the prepared liquid glucose sample were analyzed.
A sensory evaluation was carried out for two jujubes samples, which were prepared
using market liquid glucose and prepared liquid glucose and compared the organoleptic properties of both products.
From the findings of this study, it can be concluded that the best combination of acid
concentration and pressure level for the optimum hydrolysis of cassava starch at 120
°C is 6M and 137.88x103 Nm'2 respectively. The prepared liquid glucose is grayish
yellow in colour, Dextrose Equivalent value is 37.9 and the TSS is 82%. Also the moisture content and the total ash content of the prepared liquid glucose sample are 16.52% and 2.73% respectively.
The results of the sensory evaluation reveal that there is no significant difference of organoleptic properties i.e. colour, smell, texture, taste, appearance and acceptability
between the two jujubes samples. It implies that there is no significant difference of
functional properties between liquid glucose available in the market and prepared liquid glucose using cassava starch.
