Microbial diversity and antibacterial mechanism of slightly acidic electrolyzed water against Pseudomonas fluorescens in razor clam during storage

Razor clam (Sinonovacula constricta), as an economically important bivalve species, is widely distributed in the eastern coastal area, especially Ningbo of Zhejiang province. The harvest season for razor clams of each year is April-June, and its quality and flavor is the best at this time. Fresh razor clam is highly appreciated during this period due to its unique flavor, reasonable nutritional structure (low fat with high protein) and some medicinal values (etc. anti-inflammatory, anti-inebriation). However, highly perishability and challenges in storage are notable problems for razor clam industry due to its high Aw, rich nutrients, and moderated pH. Thus far, low-temperature storage with mud packing is the most common preservation method of razor clam since its high efficiency, low cost and mature technology. But this method still has inevitable problems including fluid loss, fat rancidity, microstructure disarrangement and growth of microorganisms. Attention should be paid to microbial growth during the storage of razor clam, especially the specific spoilage or dominant spoilage bacteria (SSOs). SSOs are specific microbial flora with high spoilage potential and rapid growth rate and its proportion will increase rapidly with the extension of storage time. It has been published that the SSOs affects the corruption process and deterioration of quality of aquatic products. Most SSOs in aquatic products are Gram-negative bacteria, such as Pseudomonas, Shewanella, Aeromonas, Lactobacillus and so on. And the type, quantity proportion and corruption potential of the SSOs are influenced by the types of aquatic products, breeding mode, storage environment and so on. At present, the most commonly used method for the identification of SSOs is 16S rRNA gene sequencing technology.