physicochemical and functional properties of crawfish chitosan as ...
physicochemical and functional properties of crawfish chitosan as ...
physicochemical and functional properties of crawfish chitosan as ...
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The w<strong>as</strong>tewater rele<strong>as</strong>ed from food processing plants typically seafood, dairy or meat<br />
processing industries contains appreciable amount <strong>of</strong> protein which can be recovered with the<br />
use <strong>of</strong> <strong>chitosan</strong>; this protein, after drying <strong>and</strong> sterilization, makes a great source <strong>of</strong> feed additives<br />
for farm animals (Rout, 2001).<br />
The removal <strong>of</strong> dyes is difficult to achieve because <strong>of</strong> their high resistance to degradation<br />
by light, chemical, biological, <strong>and</strong> other exposures. However, chitin <strong>and</strong> <strong>chitosan</strong> have been<br />
found to have extremely high affinity for dyes which may contribute to aquatic toxicity (Rout,<br />
2001). Asano et al. (1978) found that <strong>chitosan</strong> is effective for conditioning municipal <strong>and</strong><br />
industrial sludge due mainly to their effectiveness in sludge conditioning, rapid biodegradability<br />
in soil environments, <strong>and</strong> economic advantages in centrifugal sludge dewatering.<br />
2.6.2 In the Food Industry<br />
The food processing industry extensively uses polysaccharides in food product<br />
development <strong>and</strong> processing for the purpose <strong>of</strong> imparting desirable <strong>functional</strong> <strong>properties</strong> such <strong>as</strong><br />
thickening, gelling, emulsifying, <strong>and</strong> whipping. Without exception, <strong>chitosan</strong> have been<br />
documented to possess several distinctive <strong>properties</strong> (Knorr, 1984). The good water uptake <strong>of</strong><br />
<strong>chitosan</strong> h<strong>as</strong> been found to be significantly higher than that <strong>of</strong> microcrystalline cellulose (Knorr,<br />
1982).<br />
Several studies have also demonstrated the effectiveness <strong>of</strong> <strong>chitosan</strong> for coagulation <strong>and</strong><br />
recovery <strong>of</strong> suspended solids in processing w<strong>as</strong>tes from poultry (Bough et al., 1975), eggs<br />
(Bough, 1976), seafood (Bough, 1976) <strong>and</strong> vegetable operations (Bough, 1975). These studies<br />
indicate that <strong>chitosan</strong> can reduce the suspended solids <strong>of</strong> various food processing w<strong>as</strong>tes by 70 to<br />
98%. Chitosan also is effective for dewatering activated sludge suspensions resulting from<br />
biological treatment <strong>of</strong> brewing <strong>and</strong> vegetable canning w<strong>as</strong>tes (Bough, 1976)<br />
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