physicochemical and functional properties of crawfish chitosan as ...

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