Kinetic modeling of polyphenoloxidase inactivation during thermal-assisted high pressure processing in black tiger shrimp (Penaeus monodon)

Effects of Ultra-High Pressure on Endogenous Enzyme Activities, Protein Properties, and Quality Characteristics of Shrimp (Litopenaeus vannamei) during Iced Storage

The present study aimed to explore the effects of ultra-high pressure (UHP) on the cathepsin (B, D, H, and L) activities, protein oxidation, and degradation properties as well as quality characteristics of iced shrimp (Litopenaeus vannamei). Fresh shrimps were vacuum-packed, treated with UHP (100–500 MPa for 5 min), and stored at 0 °C for 15 days. The results showed that the L* (luminance), b* (yellowness), W (whiteness), ΔE (color difference), hardness, shear force, gumminess, chewiness, and resilience of shrimp were significantly improved by UHP treatment. Moreover, the contents of surface hydrophobicity, myofibril fragmentation index (MFI), trichloroacetic acid (TCA)-soluble peptides, carbonyl, dityrosine, and free sulfhydryl of myofibrillar protein (MP) were significantly promoted by UHP treatment. In addition, UHP (above 300 MPa) treatment enhanced the mitochondrial membrane permeability but inhibited the lysosomal membrane stability, and the cathepsin (B, D, H, and L) activities. UHP treatment notably inhibited the activities of cathepsins, delayed protein oxidation and degradation, as well as texture softening of shrimp during storage. Generally, UHP treatment at 300 MPa for 5 min effectively delayed the protein and quality deterioration caused by endogenous enzymes and prolonged the shelf life of shrimp by 8 days.

High-pressure processing of fish and shellfish products: Safety, quality, and research prospects

Seafood products have been one of the main drivers behind the popularity of high-pressure processing (HPP) in the food industry owing to a high demand for fresh ready-to-eat seafood products and food safety. This review provides an overview of the advanced knowledge available on the use of HPP for production of wholesome and highly nutritive clean label fish and shellfish products. Out of 653 explored items, 65 articles published during 2016-2021 were used. Analysis of the literature showed that most of the earlier work evaluated the HPP effect on physicochemical and sensorial properties, and limited information is available on nutritional aspects. HPP has several applications in the seafood industry. Application of HPP (400-600 MPa) eliminates common seafood pathogens, such as Vibrio and Listeria spp., and slows the growth of spoilage microorganisms. Use of cold water as a pressure medium induces minimal changes in sensory and nutritional properties and helps in the development of clean label seafood products. This technology (200-350 MPa) is also useful to shuck oysters, lobsters, crabs, mussels, clams, and scallops to increase recovery of the edible meat. High-pressure helps to preserve organoleptic and functional properties for an extended time during refrigerated storage. Overall, HPP helps seafood manufacturers to maintain a balance between safety, quality, processing efficiency, and regulatory compliance. Further research is required to understand the mechanisms of pressure-induced modifications and clean label strategies to minimize these modifications.

Effects of combined ultrasound and low-temperature short-time heating pretreatment on proteases inactivation and textural quality of meat of yellow-feathered chickens

This study aimed to investigate the effect of combined ultrasound and low-temperature short-time heating (ULTSTH) (40 kHz, 0.2 W/cm² at 55 °C for 15 min) as pretreatment on proteases inactivation and textural quality of yellow-feathered chicken (YFC). Results showed ultrasound and low-temperature heating synergistically improved the inactivation of the most important meat proteases, calpain, cathepsin B and total proteases, with kinetics following the first order decay(s). Degradation of meat proteins was effectively reduced by ULTSTH compared to the pretreatment of chilling. Importantly, ULTSTH increased the firmness of breast meat and led to improved texture and microstructure. Lipid and protein oxidation of meat pretreated with ULTSTH were reduced during refrigerated storage period. Additionally, microorganisms in meat were inactivated by ULTSTH, which resulted in an obvious increase in the shelf life of meat. These findings suggested that ULTSTH is promising as an alternative pretreatment to obtain a favorable textural quality of YFC.