Physicochemical changes induced in carp (Cyprinus carpio) fillets by high pressure processing at low temperature

Migration of Nutrient Substances and Characteristic Changes of Chicken White Soup Emulsion from Chicken Skeleton during Cooking

The protein and fat in chicken skeleton can be emulsified in a boiling state to form milky white chicken soup. White chicken soup has a delicious taste, good nutritional value, a beautiful color, and volatile flavor compounds. However, cooking time significantly impacts the quality of white chicken soup. Herein, we investigated the influence of cooking time (30, 60, 90, 120, 150, 180, and 210 min) on the migration of nutrient substances and characteristics changes in white chicken soup from chicken skeletons. The results showed that nutrients such as total lipids, water-soluble protein, total sugars, solid matter, and oligopeptides in the chicken skeletons' tissue continuously migrated into the soup during the cooking process. The total nutrient content in the chicken soup was highest after cooking for 180 min. Simultaneously, the white chicken soup obtained after cooking for 180 min had low interfacial tension and high whiteness, viscosity, and storage stability. The high stability index was associated with increased ζ potential and decreased particle size. The contact angle analysis results also indicated that the stability of the white chicken soup was improved when the cooking time reached 180 min. This research provides basic information for the production of high-quality white chicken soup.

Combining high pressure and electric fields towards Nannochloropsis oculata eicosapentaenoic acid-rich extracts

Nannochloropsis oculata is naturally rich in eicosapentaenoic acid (EPA). To turn this microalga into an economically viable source for commercial applications, extraction efficiency must be achieved. Pursuing this goal, emerging technologies such as high hydrostatic pressure (HHP) and moderate electric fields (MEF) were tested, aiming to increase EPA accessibility and subsequent extraction yields. The innovative approach used in this study combined these technologies and associated tailored, less hazardous different solvent mixtures (SM) with distinct polarity indexes. Although the classical Folch SM with chloroform: methanol (PI 4.4) provided the highest yield concerning total lipids (166.4 mg_lipid/g_biomass), diethyl ether: ethanol (PI 3.6) presented statistically higher values in terms of EPA per biomass, corresponding to 1.3-fold increase. When SM were used in HHP and MEF, neither technology independently improved EPA extraction yields, although the sequential combination of technologies did result in 62% increment in EPA extraction. Overall, the SM and extraction methodologies tested (HHP-200 MPa, 21 °C, 15 min, followed by MEF processing at 40 °C, 15 min) enabled increased EPA extraction yields from wet N. oculata biomass. These findings are of high relevance for the food and pharmaceutical industries, providing viable alternatives to the "classical" extraction methodologies and solvents, with increased yields and lower environmental impact. KEY POINTS: • Et₂O: EtOH is a less toxic and more efficient alternative to Folch solvent mixture • HHP or MEF per se was not able to significantly increase EPA extraction yield • Combinations of HHP and MEF technologies increased both lipids and EPA yields.

Effect of lipid oxidation on quality attributes and control technologies in dried aquatic animal products: a critical review

Aquatic animals are viewed as a good source of healthy lipids. Although drying is an effective method for the preservation of aquatic animal products (AAPs), the whole process is accompanied by lipid oxidation. This article reviews the main mechanism of lipid oxidation in the drying process. It also summarizes the effects of lipid oxidation on the quality of dried aquatic animal products (DAAPs), including nutrients, color, flavor, and hazard components, especially for those harmful aldehydes and heterocyclic amines. In addition, it concluded that moderate lipid oxidation contributes to improving the quality of products. Still, excessive lipid oxidation produces hazardous substances and induces health risks. Hence, to obtain high-quality DAAPs, some effective control technologies to promote/prevent lipid oxidation are introduced and deeply discussed, including salting, high-pressure processing, irradiation, non-thermal plasma technology, defatting treatments, antioxidants, and edible coating. A systematic review of the effect of lipid oxidation on quality attributes and control technologies in DAAPs is presented, and some perspectives are made for future research.

Process optimization and evaluation of the effects of different time-temperature sous vide cooking on physicochemical, textural, and sensory characteristics of whiteleg shrimp (Litopenaeusvannamei)

The objective of the current study was to optimize the cook-chill conditions of high-value whiteleg shrimp (Litopenaeus vannamei) processed using the sous vide (SV) technique and to assess the effects of various time-temperature combinations on the physicochemical, textural, and sensory qualities. For optimization, a Response Surface Methodology (RSM) approach utilizing a Central Composite Design (CCD) was adopted. Optimum SV cooking conditions to acquire minimum texture (hardness) of 7235 g was 13.48 min and 81.87 °C, expressible moisture of 18.48% was 14.5 min and 84.5 °C, and cook loss of 5.58% was 5 min and 75 °C. Texture (hardness) and expressible moisture decreased while cooking loss increased with increasing time-temperature treatment. Redness and yellowness values increased (p < 0.05) with increasing SV cooking time-temperature, but lightness values were nearly consistent in all treatments. With increasing time and temperature, TBARs and total carotenoid content increased (p < 0.05). However, the TBARs values were within accepted limits and ranged from 0.05 to 0.08 mg malonaldehyde/kg. Sensory evaluation indicated that all SV cooked samples were well accepted, with overall scores ≥7. These results suggest that the SV cooking temperature and time had a substantial impact on the textural, physicochemical, and sensory characteristics of shrimp. In addition, increasing time-temperature increased cooking and moisture loss, but decreased hardness and higher sensory scores made the product more acceptable to consumers.

Using OPLS-DA to Fingerprint Key Free Amino and Fatty Acids in Understanding the Influence of High Pressure Processing in New Zealand Clams

This study investigated the effect of high pressure processing (HPP) on the fatty acids and amino acids content in New Zealand Diamond Shell (Spisula aequilatera), Storm Shell (Mactra murchisoni), and Tua Tua (Paphies donacina) clams. The clam samples were subjected to HPP with varying levels of pressure (100, 200, 300, 400, 500, and 600 MPa) and holding times (5 and 600 s) at 20 °C. Partial Least Squares Discriminant Analysis (PLS-DA) and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) were deployed to fingerprint the discriminating amino and fatty acids post-HPP processing while considering their inherent biological variation. Aspartic acid (ASP), isoleucine (ILE), leucine (LEU), lysine (LYS), methionine (MET), serine (SER), threonine (THR), and valine (VAL) were identified as discriminating amino acids, while C18:0, C22:1n9, C24:0, and C25:5n3 were identified as discriminating fatty acids. These amino and fatty acids were then subjected to mixed model ANOVA. Mixed model ANOVA was employed to investigate the influence of HPP pressure and holding times on amino acids and fatty acids in New Zealand clams. A significant effect of pressure levels was reported for all three clam species for both amino and fatty acids composition. Additionally, holding time was a significant factor that mainly influenced amino acid content. butnot fatty acids, suggesting that hydrostatic pressure hardly causes hydrolysis of triglycerides. This study demonstrates the applicability of OPLS-DA in identifying the key discriminating chemical components prior to traditional ANOVA analysis. Results from this research indicate that lower pressure and shorter holding time (100 MPa and 5 s) resulted in the least changes in amino and fatty acids content of clams.

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.

High hydrostatic pressure combined with moisture regulators improves the tenderness and quality of beef jerky

The influence of high hydrostatic pressure (HHP) at different pressure levels (0.1, 100, 200, and 300 MPa) combined with moisture regulators (MR) on the tenderness, water content, and quality of beef jerky was investigated. HHP treatment reduced the shear force (SF) of beef jerky (P < 0.05). The beef jerky treated with MR+HHP exhibited higher tenderness than the beef jerky treated only with HHP (P < 0.05). The MR+HHP samples had significantly higher moisture content than the HHP samples (P > 0.05) when the water activity was maintained at approximately 0.7. MR+HHP contributed to a shorter T₂₁ value and a higher P₂₁ value, which indicated an improvement in the water-binding ability of the beef muscle. Analysis of the microstructure showed that MR+HHP led to the fracture of the Z-line and destruction of the sarcomere structure. Sensory analysis showed that MR+HHP-200 samples had significantly higher tenderness and overall acceptable scores than other samples (P < 0.05).

Non-Thermal Methods for Ensuring the Microbiological Quality and Safety of Seafood

A literature search and systematic review were conducted to present and discuss the most recent research studies for the past twenty years on the application of non-thermal methods for ensuring the microbiological safety and quality of fish and seafood. This review presents the principles and reveals the potential benefits of high hydrostatic pressure processing (HHP), ultrasounds (US), non-thermal atmospheric plasma (NTAP), pulsed electric fields (PEF), and electrolyzed water (EW) as alternative methods to conventional heat treatments. Some of these methods have already been adopted by the seafood industry, while others show promising results in inactivating microbial contaminants or spoilage bacteria from solid or liquid seafood products without affecting the biochemical or sensory quality. The main applications and mechanisms of action for each emerging technology are being discussed. Each of these technologies has a specific mode of microbial inactivation and a specific range of use. Thus, their knowledge is important to design a practical application plan focusing on producing safer, qualitative seafood products with added value following today’s consumers’ needs.

Innovative Seafood Preservation Technologies: Recent Developments

Fish and fishery products are among the food commodities of high commercial value, high-quality protein content, vitamins, minerals and unsaturated fatty acids, which are beneficial to health. However, seafood products are highly perishable and thus require proper processing to maintain their quality and safety. On the other hand, consumers, nowadays, demand fresh or fresh-like, minimally processed fishery products that do not alter their natural quality attributes. The present article reviews the results of studies published over the last 15 years in the literature on: (i) the main spoilage mechanisms of seafood including contamination with pathogens and (ii) innovative processing technologies applied for the preservation and shelf life extension of seafood products. These primarily include: high hydrostatic pressure, natural preservatives, ozonation, irradiation, pulse light technology and retort pouch processing.

Supercritical carbon dioxide pasteurization to reduce the activity of muscle protease and its impact on physicochemical properties of Nile tilapia

The studies of the effect of supercritical carbon dioxide (scCO2) pasteurization on solid food from fish origin are scarcely available. This study was intended to address that gap by investigating the effect of scCO2 on the reduction of muscle protease activity and its impact on physicochemical properties of the Nile tilapia. Tilapia were exposed to CO2 pressure at 70, 75, 80, 85, and 90 bar; temperature at 40 °C; and holding time for 15 min. This study discovered that 80 bar was the minimum pressure to achieve half residual activity of muscle protease and two logs reductions of microbial counts. The applications of 80 and 85 bar were found to achieve significant reduction of tilapia muscle protease activity while still maintained acceptable textural properties. Both 80 and 85 bar were found to be effective to inhibit softening development of tilapia fillet during 14 days of chilled storage. Eighty-five bar and 15 min CO2 pasteurization was considered as maximum level of CO2 pressure that tilapia could withstand without degrading its texture significantly.

Physicochemical Properties and Consumer Acceptance of High-Pressure Processed, Sous Vide-Cooked Lobster Tails

Sous vide (SV) and high-pressure processing (HPP) are promising techniques in the development of high-quality seafood products. The objectives of this study were to evaluate the impacts of HPP on the physicochemical quality and consumer acceptance of subsequently SV-cooked lobster tails. Raw shucked lobster tails were processed at 150 or 350 MPa for 5 or 10 min. Subsequently, half were SV cooked to a core temperature of 65 °C/10 min. Texture profile analysis, shear force, color, salt soluble protein content, water-holding capacity (WHC), moisture content, and weight loss were analyzed. Pressurization at 150 MPa/10 min decreased (P < 0.05) the hardness of raw lobsters compared to non-HPP-treated controls. However, 350 MPa for 5 or 10 min increased (P < 0.05) the shear force in raw and SV-cooked samples. HPP increased (P < 0.05) the L^* values but did not affect moisture content, WHC, or weight loss of raw or SV-cooked lobsters. Lobsters were subjected to consumer acceptability testing using a 9-point hedonic scale. Although panelists rated the flavor, texture, and overall liking of the 350 MPa/10 min samples higher than the control and 150 MPa/10 min samples, there were no significant differences among treatment means, indicating that physicochemical changes induced by HPP did not affect consumer acceptance. In addition, approximately 84% of panelists reported that the 350 MPa product met their expectations compared to approximately 75% for the control and 150 MPa treatments. These results suggest that HPP has the potential to be applied in combination with SV cooking to produce consumer-acceptable, value-added lobster products. PRACTICAL APPLICATION: Lobsters are an expensive menu item in restaurants. However, they are susceptible to being overcooked using conventional methods, producing a tough and rubbery texture. Sous vide cooking is reported to provide evenly cooked lobsters with a succulent and juicy texture. In this study, lobsters were sous vide cooked to reach a core temperature of 65 °C, and then maintained at that temperature for 10 min. The application of moderate processing pressures to vacuum-packaged raw lobsters prior to SV cooking altered some physicochemical attributes but has the potential to increase the availability of high-quality, minimally processed seafood with good consumer acceptability.

Effect of chitosan on shelf life of restructured fish products from pangasius (pangasianodon hypophthalmus) surimi during chilled storage

In the present study, restructured products were prepared from pangasius surimi and their qualities were analysed under chilled storage. Pangasius surimi had 75.82 % moisture, 16.91 % protein, 2.76 % fat and 0.95 % ash. Restructured products were prepared in three different formulations by incorporating corn starch (10 %) and chitosan (0.75 %). Formulation containing only corn starch (10 %) was served as control. In all the formulations, mono unsaturated fatty acids were higher (45.14 %). The total volatile base nitrogen (TVB-N) showed an increasing trend and it was found to be higher in control (4.8 mg/100 g) on 10(th) day than the chitosan incorporated sample (3.5-4.2 mg/100 g) on 17(th) day during chill storage. Similarly, peroxide value (PV) was found to higher (8.85 milliequivalent of O2/kg) in control than the chitosan incorporated sample (4.5-6.8 milliequivalent of O2/kg) on 10(th) day. All the three formulations had an acceptable level of thiobarbituric acid (TBA) value that ranged between 0.023-0.098 mg of malanoldehyde/kg during chilled storage. Based on the sensory and microbiological analysis, products prepared without chitosan had a shelf life of 10 day whereas, products incorporated with chitosan had an extended shelf life of 17 day.

Changes in the Content of Biogenic Amines and Fatty Acids in High Pressure-Processed Carp Flesh (Cyprinus carpio)

Biogenic amine and fatty acid contents were determined in vacuum-packed fillets of common carp (Cyprinus carpio). Samples were pressure treated at 300 and 500 MPa and were stored at 3.5 and 12°C for up to 28 days (control, 0 MPa) and 70 days (pressure-treated). The content of eight biogenic amines (putrescine, cadaverine, spermidine, spermine, histamine, tyramine, tryptamine, and phenylethylamine) were determined. Putrescine and cadaverine were influenced by all factors (temperature, pressurization level, and time of storage). Tyramine content was the most sensitive indicator of the improper status of sample; levels exceeding 10 mg/kg indicated both the loss of meat freshness and temperature abuse, in spite of persisting good sensory indices. Neither storage temperature nor pressurization level had a statistically important effect on the contents of fatty acids. Only polyunsaturated fatty acids decreased slightly if the storage time exceeded 42 days.