Effect of High Hydrostatic Pressure Treatment on Urease Activity and Inhibition of Fishy Smell in Mackerel (Scomber japonicus) during Storage

Abstract

affecting the nutritional properties and flavor [5][6][7]. Consequently, the application of HHP treatment technology has been increasing recently, and various effects of HHP treatment on fish have been reported depending on different factors, such as the nature of the species and its size and chemical composition [8,9].Products studied by introducing HHP treatment technology include fruits, salad dressings, yogurt, juice, andthis study, the physicochemical changes related to fishy smell were determined by storing high hydrostatic pressure (HHP)-treated mackerel (Scomber japonicus) meat in a refrigerator for 20 days. The inhibition of crude urease activity from Vibrio parahaemolyticus using HHP treatment was also investigated. The mackerel meat storage experiment demonstrated that production of trimethylamine (TMA) and volatile basic nitrogen (VBN), the main components of fishy smell, was significantly reduced on the 20th day of storage after the HHP treatment compared to the untreated mackerels. The results demonstrated that the increased ammonia nitrogen rates in the 2000, 3000, and 4000 bar, HHP-treated groups decreased by 23.8%, 23.8%, and 31.0%, respectively, compared to the untreated groups. The enzyme activity of crude urease was significantly reduced in the HHPtreated group compared to that in the untreated group. Measurement of the volatile organic compounds (VOCs) in mackerel meat during storage indicated that the content of ethanol, 2butanone, 3-methylbutanal, and trans-2-pentenal, which are known to cause off-flavor due to spoilage, were significantly reduced by HHP treatment. Collectively, our results suggested that HHP treatment would be useful for inhibiting the activity of urease, thereby reducing the fishy smells from fish and shellfish.

Improving the microbiological safety and quality of aquatic products using nonthermal processing

“…Figure 4a illustrates the proposed mechanism. (Kim et al, 2021;Lin et al, 2021;Liu et al, 2022). The efficacy of UHP on microbiota was confirmed in tuna (Tsai et al, 2022), scallop (Mizuhopecten yessoensis) (Chen et al, 2021), and grass carp (Yu et al, 2018).…”

“…After death, the TMAO in fish and shellfish is reduced by bacteria or enzymes to TMA, producing a fishy odor. Kim et al (2021) applied UHP (200, 300, and 400 MPa for 3 min) to mackerel meat and monitored changes in TMA levels during storage at 4 • C. On day 20 of storage, compared to the control group, TMA levels decreased by 12%, 36%, and 70% in the 200, 300, and 400 MPa treated groups, respectively. The 400 MPa treatment maintained consistent freshness over the course of 20 days of storage.…”

“…Color (L*, a*, b*) is an essential freshness indicator. Multiple studies have shown that UHP treatment can enhance the brightness (L*) of seafood (Chen et al, 2021;de Alba et al, 2019;Kim et al, 2021;Suemitsu & Cristianini, 2019;Tsai et al, 2022). Tsai et al (2022) observed that the yellowness (b*), whiteness (W*), and color difference (ΔE*) of tuna increased with higher UHP pressures.…”

“…(particularly S. putrefaciens ), and Pseudomonas spp. in various seafoods, such as oyster ( Crassostrea ariakensis ), mackerel ( Scomber japonicus ), and red claw crayfish ( Cherax quadricarinatus ) (Kim et al., 2021; Lin et al., 2021; Liu et al., 2022). The efficacy of UHP on microbiota was confirmed in tuna (Tsai et al., 2022), scallop ( Mizuhopecten yessoensis ) (Chen et al., 2021), and grass carp (Yu et al., 2018).…”

“…Color ( L *, a *, b *) is an essential freshness indicator. Multiple studies have shown that UHP treatment can enhance the brightness ( L *) of seafood (Chen et al., 2021; de Alba et al., 2019; Kim et al., 2021; Suemitsu & Cristianini, 2019; Tsai et al., 2022). Tsai et al.…”