Extraction and characterization of chitin and chitosan from Nile tilapia scale in Lake Chamo, Arba Minch and their application in clarification of apple juice

Abstract

Fish and seafood processing industries generate large quantities of waste, which are at the origin of several environmental, economic and social problems. However, fish waste contains high value-added substances such as collagen, gelatin, chitin and chitosan. In Ethiopia, Arba Minch is one of the leading areas of fish production zone, and hence, everyday lot of fish waste has been generated due to this. This work has focused on the extraction and characterization of chitin and chitosan from fish wastes (Nile tilapia). The chitin and chitosan extracted were characterized by analyzing parameters such as percentage yield, moisture and ash content, solubility, degree of deacetylation, water binding capacity, fat binding capacity, intrinsic viscosity and Molecular weight (M w ). The results obtained from this study show that the yield of chitin and chitosan was 29.88 ± 0.01% and 15.87 ± 0.14%, respectively. The moisture and ash content, DD, solubility, FBC, WBC, intrinsic viscosity and M w of the extracted chitosan were found to be 6.79 ± 0.40%, 1.22 ± 0.16%, 85.25 ± 0.28%, 94.3 ± 0.99%, 391.17 ± 0.13%, 461.34 ± 0.42%, 6.832 ± 0.0101 and 3514.730 ± 1.1 g/mol, respectively. The chitosan was then employed for apple juice clarification and the reduction in total soluble solids value from (12.67 to 9.20), titratable acidity (2.38 to 1.61) and turbidity (320.2 to 86.6) after treatments have confirmed their effectiveness on apple juice clarification. The reduction in titratable acidity has been supported by increase in pH value (3.19 to 4.29). The sensory evaluation of control juice and chitosan-added juice samples was performed, and it has been observed that chitosan concentration of up to 0.25 g/L was well accepted by the consumers. Novelty impact statement:• The current study is the first kind of attempt to analyze the different physicochemical properties of chitin and chitosan obtained from Nile tilapia fish scale wastes, from Lake Chamo, Arba Minch.• It also throws light on how fish scale wastes can be converted into useful products like chitin and chitosan.• The application of extracted chitosan in apple juice clarification has been successfully demonstrated in the study.

Application of natural fining agents to clarify fruit juices

“…Lare et al. (2022) applied chitosan obtained from fish wastes (Nile tilapia) for apple juice clarification. The juice turbidity decreased with increasing chitosan concentration and flocculation time.…”