Changes in the microstructure and enzymatic hydrolysis performance of chitin treated by steam explosion, high‐pressure homogenization, and γ radiation

Abstract

This research intends to reduce the crystallinity of chitin with physical methods so as to improve the enzymatic hydrolysis efficiency of chitin. Scanning electron microscopy showed that both steam explosion and high‐pressure homogenization significantly enlarged the pores in shrimp shells, which are made up of chitin, but γ radiation did not. X‐ray diffraction showed that the crystallinity index of chitin decreased by 23.2% in the (110) plane and 24.7% in the (020) plane after three rounds of steam explosion and decreased by 12.4% in the (110) plane and 28.7% in the (020) plane after three rounds of high‐pressure homogenization. After γ radiation, however, there was no significant change. The corresponding deacetylation degrees of the chitin treated with steam explosion and high‐pressure homogenization increased by 13.2 and 5.7%, respectively. The natural, steam‐exploded and high‐pressure homogenized chitins respectively produced 0.251, 0.145, and 0.407 mg/ml reducing sugars with the hydrolysis of Streptomyces griseus chitinase. However, when hydrolyzed by Paenibacillus sp. A1 chitinase the steam‐exploded and the high‐pressure homogenized chitin respectively released 40 and 300% more reducing sugars than the natural chitin. The results found that steam explosion and high‐pressure homogenization can reduce the crystallinity of chitin, and make it prone to enzymatic hydrolysis.

Effects of high hydrostatic pressure on peelability and quality of crayfish(Procambarus clarkii)

“…Crayfish are one of the most important raw materials for commercial chitin 25 . High‐pressure treatment can reduce the crystallinity of chitin, thereby leading to easier crayfish peeling 26 …”

“…25 High-pressure treatment can reduce the crystallinity of chitin, thereby leading to easier crayfish peeling. 26…”

Chitin oligosaccharides for the food industry: production and applications

“…Studies have shown that ultrasound can enhance the binding ability of chitinase and chitin, with the maximum binding force of 105.33 ± 23.51 pN and the loading speed at 0.3 μm/s [59]. In addition, steam explosion was also used for the pretreatment of chitin, which reduced the crystallinity of chitin through the generated pressure and thermal effects, thus improving the efficiency of enzymatic degradation [60,61].…”

“…The final products hydrolyzed from 1 g of treated chitin were 0.1 g (GlcNAc) 2 and (Glc-NAc) 3 . Ultrasonic treatment, steam explosion, and ball milling were also used for the pretreatment of chitin to assist in enzymatic degradation [56,[59][60][61]. In addition, microbial fermentation is also an effective way to pretreat chitin, which can greatly reduce the crystallinity and MW of chitin and is more conducive to the hydrolysis of chitinase [78].…”

Effect of Combined High-Pressure Homogenization and Biotechnological Processes on Chitin, Protein, and Antioxidant Activity of Cricket Powder-Based Ingredients

“…Since cricket powder contains chitin, the impact of HPH on this constituent is also very important. In fact, HPH treatment (60-80 MPa) can reduce the crystallinity and improve enzymatic hydrolysis efficiency of chitin increasing the concentration of N-Acetyl-glucosamine [19,20].…”