Biodegradable film is defined as a film that can be recycled and can be
destroyed naturally. One of the polysaccharides that can be made biodegradable
films is glucomannan. Porang tuber flour has a hydrocolloid component
(glucomannan), which lacks the ability to protect the product against oxygen, carbon
dioxide and lipids and lacks the desired mechanical properties such as less elastic
and easy to tear, it is necessary to add Na Alginate which functions to increase
elasticity, reduce risk of breaking, tearing and destroying the formed biodegradable
film. The purpose of this study was to determine the results of using glucomannan
from porang tubers as a biodegradable film with the addition of 2.5% and 3% Na
Alginate variations.
The research method was carried out by starting with graded washing of
porang flour with ethanol 50% and 80%. Washing process with graded ethanol to
increase glucomannan content and decrease calcium oxalate content. The basic
ingredients of the film used are glucomannan and sodium alginate 2,5% and 3%.
Alginate is a natural polysaccharide that is viscous and soluble in water. The
conditions are very potential to be used as bioplastics. The property of alginate is its
ability to form films.
The results show from the tests that have been carried out on samples in the
manufacture of biodegradable films based on glucomannan and alginate. The results
of stratified washing obtained yield of 63.30%, for glucomannan content obtained an
average of 48.51, the resulting biodegradable film is pretty good and elastic.
Thickness test on glucomannan film with the addition of 2.5% Alginate concentration
obtained an average result of 0.23mm and 3% Alginate obtained an average result
of 0.25mm. The resulting swelling test is quite large, namely for glucomannan films
with the addition of 2.5% Alginate concentration on average 183.72% and Na
alginate with 3% concentration on average 102.93%. For biodegradation results,
glucomannan with a concentration of 2.5% Alginate was degraded on days 6, while
3% Alginate was degraded on days 9.
Key words : Biodegradable film, Glucomannan, Na Alginate