Evaluation of a clean fermentation-organic acid method for processing shrimp waste from six major cultivated shrimp species in China

Abstract The present study aimed to discuss the applicability of a clean fermentation-organic acid method for various sources of shrimp waste (shrimp head and shell). Six major cultivated shrimp species in China, including Penaeus vannamei, Penaeus monodon, Fenneropenaeus chinensis, Penaeus japonicus, Macrobrachium rosenbergii, and Procambarus clarkii, were selected as the sources of shrimp waste. The numerical ranges of the corresponding characteristic biochemical indicators were as follows: moisture, 69.47%–79.44%; ash, 21.01%–39.11%; crude protein, 29.65%–46.04%; and crude lipid, 3.18%–9.64%; the data indicated that these types of shrimp waste were good sources for the extraction of chitin, protein and elemental calcium. The traditional chemical method and fermentation-organic acid method were used, and the results of processing the shrimp waste were compared. The results indicated that the purity of the chitin extracted by the fermentation-organic method was as good as the purity of the extracted by the chemical method. Moreover, chitin extracted by the fermentation-organic method had lower acetylation rate, crystallinity index and thermal stability compared with that of chitin extracted by the chemical method. These characteristics indicate that chitin extracted by the fermentation-organic method could be easily deacetylated or degraded leading to easier production of chitin derivatives, such as chitosan or chitooligosaccharides, from this type of chitin. Protein and calcium could be efficiently recycled during the chitin extraction process producing high nutrition protein raw material and high purity calcium citrate. These results suggest a cleaner method for the treatment of the shrimp waste generated from the major cultivated shrimp species in China.