Production of High Viscosity Chitosan from Biologically Purified Chitin Isolated by Microbial Fermentation and Deproteinization

Table 4

Properties of chitin flakes obtained from chemical and two-step biological processes.

Properties	Shrimp chitin flake products
	Chemical process	Biological process
pH	7	7
Appearance	White	White and light yellow
Crude protein (%, w/w)	0.3±0.1	3.8±1.3
Ash (%, w/w)	0.6±0.1	1.7±0.4
Deproteination efficacy (%)	99.7±0.1	96.8±0.7
Decalcification efficacy (%)	99.0±0.1	98.1±0.3
Color properties
𝐿^∗	87.3±1.6	84.7±1.2
𝑎^∗	0.3±0.1	0.7±0.2
𝑏^∗	7.0±0.1	7.2±1.4
WI^a	85.5	83.1
Degree of acetylation (%)	96.5±0.3	98.2±0.5
Viscosity^b (mPa·s)	82.0±13.6	110.0±15.1
Yield (%)	20.0±0.5	25.4±1.2

awhiteness index, by calculation.
^bviscosity determined at shear rate of 20 s⁻¹ (25°C).