For residents of Zhanjiang, Guangdong province, few pleasures examine to savoring recent seafood year-round. And for Liu Kaidong and Liang Fengyan, the native delicacies have yielded excess of culinary delight.
Liu, dean of the School of Life Science and Technology at Zhanjiang”s Lingnan Normal University, and Liang, a trainer on the college, helmed a analysis workforce to develop a chitosan-based high-value utilization technology for shrimp and crab shell waste, turning the discarded byproducts into invaluable sources.
The progressive technology has emerged as a technical cornerstone for fruit and vegetable preservation, in addition to aquaculture illness management and aquaculture wastewater therapy.
“We extract chitin from shrimp and crab shells to obtain a natural polysaccharide called chitosan through deacetylation. Chitosan is naturally degradable and possesses antibacterial properties,” Liu stated in an interview with China Daily.
“With chitosan as the core material, we integrate physical, chemical and composite technologies to develop preservation materials, shrimp pathogen control agents and adsorption materials for marine aquaculture wastewater. The core goal of this technology is to cut losses and boost revenues.”
By adopting the built-in strategy of “functional modification plus forming processing”, the answer incorporates technical pathways for dip-coating/spray-coating movie formation, ionic-covalent cross-linking, and microencapsulation technology.
These applied sciences take full benefit of chitosan’s pure film-forming properties, in addition to the antimicrobial and antioxidant capabilities of pure plant extracts, enabling focused customization to satisfy the preservation necessities of various vegatables and fruits.
“Through dipping/spraying coating, aerogel pad and microencapsulation methods, we can extend the shelf life of fruits and vegetables by two to three times, inhibit more than 80 percent of common pathogenic bacteria, and reduce moisture and nutrient loss significantly,” Liu stated.
“For instance, the ambient-temperature freshness preservation period for lychee can be extended to six to eight days, while the decay rate of papaya can be lowered to below 5 percent. Given that the preservation material is derived from natural biodegradable substances, it is fully degradable.”
Liu stated that in comparison with conventional chemical preservatives, chitosan is greener, safer, non-toxic and extra eco-friendly, whereas delivering higher preservation outcomes. The technology can minimize annual fruit and vegetable losses in Zhanjiang by 300,000 to 750,000 metric tons, translating to further income of 600 million ($87 million) to 1.5 billion yuan.
“What’s more, it helps high-quality produce command a price premium of 10 percent to 20 percent, boosting the region’s total annual revenue by 8 million to 2 billion yuan and fueling industrial transformation,” he stated.
When it involves stopping and controlling shrimp and crab pathogens, the technology is utilized in two methods: water dispersion and feed supplementation. “This can inhibit over 90 percent of pathogens like Vibrio parahaemolyticus, lowering the incidence of shrimp vibriosis to below 5 percent and increasing survival rates by 15 percent to 25 percent. It is highly versatile, with strong compatibility for crustaceans, fish and shellfish,” Liu stated.
But for delicate seedlings akin to sea cucumber fry and abalone fry, the focus have to be strictly managed or low-irritation modified merchandise ought to be adopted, whereas method concentrations have to be adjusted primarily based on whether or not the applying state of affairs is a marine or freshwater aquaculture system, he added.
The technology has additionally introduced substantial financial advantages to Zhanjiang’s shrimp farming trade. Liu identified that it could actually increase the town’s annual shrimp output by 80,000 to 240,000 tons, straight including 2.4 billion to 7.2 billion yuan in income.
In addition, it cuts prices by 500 to 1,000 yuan per mu (about 0.067 hectares) and helps shrimp fetch a ten % to fifteen % worth premium, creating complete annual direct advantages starting from 3 billion to eight.5 billion yuan.
Located on Leizhou peninsula, Zhanjiang, the southernmost coastal metropolis on the Chinese mainland, has been dubbed the nation’s “seafood capital”. It boasts plentiful shrimp and crab sources and a well-developed aquaculture and processing trade. Large portions of shrimp and crab shells are discarded by native eating places and inns yearly, and if not correctly dealt with, such marine strong waste may simply result in useful resource waste and environmental strain, stated Liu.
Liu stated his workforce will proceed to advertise the mixing of scientific analysis with native industrial improvement, driving future inexperienced progress of the marine financial system.
Xie Ruiqi contributed to this story.