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.

Chemical-Based Methodologies to Extend the Shelf Life of Fresh Fish-A Review.

Due to its characteristics, fresh fish is a highly perishable food with a very short shelf-life under refrigeration. Several methods have been introduced to slow down its deterioration, such as by means of oxygen depletion of the food package (vacuum packaging), or by changing the natural atmosphere that is in contact with the fresh fish (modified atmosphere packaging), or by the use of chemicals generally recognized as safe: such compounds can be directly applied (by dipping or spraying) or incorporated into packaging materials and slowly migrate to the product, exerting a hurdle effect against microbial development and lipid oxidation (active packaging). This review aims to cover the most recent advances in chemical-based approaches for fresh fish preservation, applied either singly or in combination.

Fresh Fish Degradation and Advances in Preservation Using Physical Emerging Technologies.

Fresh fish is a highly perishable food characterized by a short shelf-life, and for this reason, it must be properly handled and stored to slow down its deterioration and to ensure microbial safety and marketable shelf-life. Modern consumers seek fresh-like, minimally processed foods due to the raising concerns regarding the use of preservatives in foods, as is the case of fresh fish. Given this, emergent preservation techniques are being evaluated as a complement or even replacement of conventional preservation methodologies, to assure food safety and extend shelf-life without compromising food safety.

Enhanced preservation of vacuum-packaged Atlantic salmon by hyperbaric storage at room temperature versus refrigeration.

Hyperbaric storage at room temperature (HS/RT: 75 MPa/25 °C) of vacuum-packaged fresh Atlantic salmon (Salmo salar) loins was studied for 30 days and compared to atmospheric pressure at refrigerated temperatures (AP/5 °C, 30 days) and RT (AP/25 °C, 5 days). Most of the fatty acids were not affected by storage conditions, with only a slight decrease of docosahexaenoic acid (DHA) content (n-3 polyunsaturated fatty acid) for AP samples, reflected in the lower polyene index values obtained and higher oxidation extent. For HS, a lower lipid oxidation extension and a slower increase of myofibrillar fragmentation index values were observed, when compared to AP samples.

Effects of high-pressure processing on fungi spores: Factors affecting spore germination and inactivation and impact on ultrastructure.

Food contamination with heat-resistant fungi (HRF), and their spores, is a major issue among fruit processors, being frequently found in fruit juices and concentrates, among other products, leading to considerable economic losses and food safety issues. Several strategies were developed to minimize the contamination with HRF, with improvements from harvesting to the final product, including sanitizers and new processing techniques. Considering consumers' demands for minimally processed, fresh-like food products, nonthermal food-processing technologies, such as high-pressure processing (HPP), among others, are emerging as alternatives to the conventional thermal processing techniques.

Hyperbaric storage at room like temperatures as a possible alternative to refrigeration: evolution and recent advances.

From 2012, the preservation of food products under pressure has been increasingly studied and the knowledge acquired has enlarged since several food products have been studied at different storage conditions. This new food preservation methodology concept called Hyperbaric Storage (HS) has gain relevance due to its potential as a replacement or an improvement to the conventional cold storage processes, such as the traditional refrigeration (RF), or even frosting, from the energetic savings to the reduction of the carbon foot-print. Briefly, HS is capable to inhibit the microbial proliferation or its inactivation which results in the extension of the shelf-life of several food products when compared to RF.

Comparative effect of a previous 150-MPa treatment on the quality loss of frozen hake stored at different temperatures.

Background: This study addresses the quality loss of European hake (Merluccius merluccius) during frozen storage. Its objective was to comparatively analyse the effect of a previous high-pressure processing (HPP) (150 MPa for 2 min) when different storage temperatures (-10, -18 and -30 °C) were employed.

Results: Most chemical quality indices (trimethylamine, TMA; dimethylamine, DMA, formaldehyde, FA; free fatty acids, FFAs) provided a marked content increase with freezing and frozen storage time, values being higher by increasing the storage temperature.

Physicochemical parameters, lipids stability, and volatiles profile of vacuum-packaged fresh Atlantic salmon (Salmo salar) loins preserved by hyperbaric storage at 10 °C.

Lipid stability, physical properties and volatiles profile of vacuum-packaged fresh Atlantic salmon (Salmo salar) loins were evaluated after hyperbaric storage at low temperature (HS/LT: 60 MPa/10 °C) and compared to atmospheric pressure and conventional refrigeration (AP/5 °C) after 5, 15 and 30 days, and at low temperature (AP/10 °C), after 5 and 15 days. No variations in drip loss and water holding capacity were observed for HS/LT samples. Compared to AP, HS/LT caused lower changes on muscle fibres, visible by scanning electron micrographs, and a decrease of resilience property (only after 30 days).

Long-Term Effect on Bioactive Components and Antioxidant Activity of Thermal and High-Pressure Pasteurization of Orange Juice.

The long-term effect of thermal pasteurization (TP) and high-pressure processing (HPP) of orange juices stored under refrigeration, on the bioactive components and antioxidant activity, was compared. Total phenolic content (TPC), flavonoid, anthocyanin, and carotenoid contents, the individual content of major phenolic components, and the antioxidant activity, were evaluated in TP- and HPP-treated juices over a 36-day period. At day 0, no significant differences in TPC, and a decrease in carotenoid content after both treatments, were observed.

Enhanced control of Bacillus subtilis endospores development by hyperbaric storage at variable/uncontrolled room temperature compared to refrigeration.

The effect of hyperbaric storage on Bacillus subtilis endospores, as a new food preservation methodology with potential to replace the conventional refrigeration processes, was assessed and compared to refrigeration. To do so, three different matrices (McIlvaine buffer, carrot juice and brain-heart infusion broth, BHI-broth) were inoculated with B. subtilis endospores and stored at 25, 50 and 100 MPa at variable/uncontrolled room temperature (18-23 °C), under refrigeration (4 °C), and room temperature at atmospheric pressure (0.

Effects of High-Pressure Treatment on the Muscle Proteome of Hake by Bottom-Up Proteomics.

A bottom-up proteomics approach was applied for the study of the effects of high-pressure (HP) treatment on the muscle proteome of fish. The performance of the approach was established for a previous HP treatment (150-450 MPa for 2 min) on frozen (up to 5 months at -10 °C) European hake ( Merluccius merluccius). Concerning possible protein biomarkers of quality changes, a significant degradation after applying a pressure ≥430 MPa could be observed for phosphoglycerate mutase-1, enolase, creatine kinase, fructose bisphosphate aldolase, triosephosphate isomerase, and nucleoside diphosphate kinase; contrary, electrophoretic bands assigned to tropomyosin, glyceraldehyde-3-phosphate dehydrogenase, and beta parvalbumin increased their intensity after applying a pressure ≥430 MPa.

Impact of different hyperbaric storage conditions on microbial, physicochemical and enzymatic parameters of watermelon juice.

Hyperbaric storage (HS) of raw watermelon juice, up to 10days at 50, 75, and 100MPa at variable/uncontrolled room temperature (18-23°C, RT) was studied and compared with storage at atmospheric pressure (AP) under refrigeration (4°C, RF) and RT, being evaluated microbiological (endogenous and inoculated), physicochemical parameters, and enzymatic activities. Ten days of storage at 50MPa resulted in a microbial growth evolution similar to RF, while at 75/100MPa were observed microbial load reductions on endogenous and inoculated microorganisms (Escherichia coli and Listeria innocua, whose counts were reduced to below the detection limit of 1.00 log CFU/mL), resulting in a shelf-life extension compared to RF.

Extension of raw watermelon juice shelf-life up to 58days by hyperbaric storage.

Hyperbaric storage (HS) of raw watermelon juice, at 50, 62.5 and 75MPa, at temperatures of 10, 15 and ≈25°C (room temperature, RT), was studied to evaluate shelf-life comparatively to refrigeration (RF, 4°C). Generally, RF caused an increase of microbial loads to values ≥6.

A first study comparing preservation of a ready-to-eat soup under pressure (hyperbaric storage) at 25°C and 30°C with refrigeration.

Hyperbaric storage (HS), storage under pressure at 25°C and 30°C, of a ready-to-eat (RTE) soup was studied and compared with refrigeration. Soup was stored at different time (4 and 8 h), temperature (4°C, 25°C, and 30°C), and pressure (0.1, 100, and 150 MPa) conditions, to compare microbial loads and physicochemical parameters.

Hyperbaric storage of melon juice at and above room temperature and comparison with storage at atmospheric pressure and refrigeration.

Hyperbaric storage (8h) of melon juice (a highly perishable food) at 25, 30 and 37°C, under pressure at 25-150 MPa was compared with atmospheric pressure storage (0.1 MPa) at the same temperatures and under refrigeration (4°C). Comparatively to the refrigerated condition, hyperbaric storage at 50/75 MPa resulted in similar or lower microbial counts (total aerobic mesophiles, enterobacteriaceae, and yeasts/moulds) while at 100/150 MPa, the counts were lower for all the tested temperatures, indicating in the latter case, in addition to microbial growth inhibition, a microbial inactivation effect.

Effect of ionic liquids alkyl chain length on horseradish peroxidase thermal inactivation kinetics and activity recovery after inactivation.

The effects of different alkyl chain lengths of ionic liquids 1-ethyl-, 1-butyl- and 1-hexyl-3-methylimidazolium chloride, on the catalytic activity, thermal stability and deactivation kinetics of horseradish peroxidase were studied in the temperature range of 45-85 °C. The presence of 1-ethyl- and 1-butyl-ionic liquids up to 25% (w/v) did not affect significantly the enzyme activity at 25 °C, whereas the addition of 1-hexyl-solvent resulted in lower activity of enzyme. Typical biphasic deactivation profiles were obtained and adequately fitted by a bi-exponential equation.