Extractability Of Myofibrillar Proteins Research Articles

Physicochemical characteristics and microbial diversity of sous vide scallops (Chlamys farreri) during chilled storage

This study investigated the impact of sous vide (SV) cooking methods on the physical and chemical characteristics as well as the microbial composition of scallops (Chlamys farreri) over a 30 days period of refrigerated storage. Scallop treatments were divided into two groups: CS (scallops vacuum-packed and then steamed for 30 min at 75 °C) and CK (scallops steamed for 15 min at 100 °C). With the increase in refrigeration time, the total volatile basic nitrogen (TVBN), pH, cooking loss, microbial content, and malondialdehyde (MDA) content gradually increased, while the water-soluble protein extraction rate and the myofibrillar protein (MP) extraction rate of the CS and CK samples significantly decreased. Notably, the SV steaming treatment effectively reduced microbial degradation of proteins, improved water retention of scallop samples, and maintained high MP extraction as compared to CK samples (MP content ranged from 1.09% to 2.50% in the CK group and 1.75%–3.33% in the CS group). During the late stages of refrigeration, conventionally cooked scallops (CK) were dominated by Pseudomonas and Psychrobacter, with the ability to produce biogenic amines, while SV steamed scallops were dominated by Psychrobacillus. Furthermore, a link was discovered between the microbial community and the physicochemical parameters.

Myofibrillar proteins’ intermolecular interaction weakening and degradation: Are they mainly responsible for the tenderization of meat containing l–arginine, l–lysine, or/and NaCl?

This study explored the effects of l–arginine, l–lysine, and NaCl alone and in combination on the tenderness of porcine meat. Arg, Lys, and NaCl alone improved the tenderness, decreased the cooking loss, and increased the myofibrillar fragmentation index (MFI) of porcine meat; Both Arg and Lys cooperated with NaCl to better achieve this effect. Furthermore, Arg/Lys collaborated with NaCl to increase muscle fiber swelling and moisture content of the meat and promoted the extraction of main myofibrillar proteins. FT–IR revealed that Arg, Lys, or NaCl alone or in combination caused changes in protein–water interactions. Western blotting revealed varying degrees of meat protein degradation in all cases, but the results did not well coincide with those of shear force and the MFI. Therefore, the weakening of intermolecular forces between myofibrillar proteins was considered the main reason for meat tenderization under the present study conditions.

Effect of processing (cutter versus continuous emulsifier) and sodium reduction on the physicochemical properties of bologna sausages.

Overcoming the impact of sodium reduction in the properties of emulsified sausages is a current challenge in the production of healthier meat products. Because the emulsifying process play a key role in the stability of sausages, the present study aimed to evaluate the effects of two mechanical emulsifying systems (cutter versus continuous emulsifier) and two levels of sodium chloride (2.50 and 1.25%) on the physicochemical characteristics of bologna sausages. A reduction of sodium increased the L* value and reduced the a* value, and also decreased the protein extraction yield in sausages produced in the cutter system. Moreover, the emulsion stability of reduced sodium batter was increased by cutter emulsification (F50C). On the other hand, the continuous emulsifier process did not decrease the extraction of myofibrillar proteins in F50E (sodium reduced treatment), resulting in minimal impact on emulsion stability and an increase in hardness in reduced-sodium sausages. Therefore, to produce low-sodium sausages, the continuous emulsifier was more effective producing batters with increased extracted myofibrillar proteins, improving the structure and functionality of myofibrillar proteins compared to the cutter process. © 2023 Society of Chemical Industry.

Functional and physicochemical properties of protein from giant squid (Dosidicus gigas) extracted using foam-aided pH-shift processing.

Jumbo squid (Dosidicus gigas) is a commercially valuable mollusk in Mexico; 80% of its body is edible. Despite the high protein content (∼18%) and low cholesterol content of this species, its high proteolytic activity (microbial and endogenous enzymes) induces protein degradation and consequent reduction in functional properties from a structural viewpoint. Gelation capacity (texture profile of the gels obtained), solubility, water holding capacity, foaming capacity, emulsification capacity, and emulsion stability were evaluated in protein concentrates obtained by foam-aided pH-shift processing: (A) myofibrillar protein extraction with distilled water and no pH-shifting; (B) alkaline solubilization and isoelectric precipitation; (C) acidic solubilization and isoelectric precipitation; and (D) process A and isoelectric precipitation. Process B showed superior gelation capacity, D had high emulsion stability across a wide range of pH values (4.0-8.0) and C lower plate counts of aerobic mesophilic. Therefore, all three alternative extraction processes showed techno-functional advantages. PRACTICAL APPLICATION: Jumbo squid is an abundant protein source in México, most of which is exported. Functional and physicochemical properties of muscle protein were improved by pH-shift processing. The recovered protein showed modifications of technological properties, using one of the methods described can lead to produce a protein extract with the most desirable attributes, such as foaming, emulsifying, or gelling capacities. The functional and physicochemical properties of protein from squid can be enhanced by selecting a certain pH-shift processing, depending on the desirable use. There is a broad perspective on the use of these protein extracts as ingredients or additives.

Effects of Sous Vide Cooking on the Physicochemical and Volatile Flavor Properties of Half-Shell Scallop (Chlamys farreri) during Chilled Storage

This study explored the effects of sous vide (SV) cooking treatments on the physicochemical quality and volatile flavor of half-shell scallop (Chlamys farreri) during 30 d of chilled storage. The vacuum-packed scallop samples were cooked at 70 °C (SV-70) and 75 °C (SV-75) and maintained for 30 min. The samples were compared with the positive control (cooked at 100 °C for 10 min, CK). The results indicate that the total volatile basic nitrogen (TVBN), pH, texture, and malondialdehyde (MDA) content gradually increased, while the myofibrillar protein (MP) extraction rate of the CK, SV-70, and SV-75 samples significantly decreased with increasing chilled storage time. Significantly, the SV cooking treatments maintained a much higher water-holding capacity of scallop muscle, compared with the conventional cooking process at 100 °C. Additionally, the SV-75 cooking treatment maintained relatively stable TVBN, pH, and MDA content, springiness, and shearing force properties of scallop samples, especially during 0-20 d of storage. Volatile flavor analysis showed that a total of 42 volatile organic compounds (VOCs) were detected in the scallop samples, and there were no considerable differences in these VOCs between the CK and SV-75 cooked samples (0 d). Overall, the SV cooking treatments effectively maintained acceptable and stable physicochemical and volatile flavor properties of half-shell scallop samples during chilled storage.

Extraction and Characterization of Myofibrillar Proteins from Different Meat Sources: A Comparative Study

In the present study, myofibrillar proteins were extracted from the meat proteins of beef, lamb, chicken, tuna and emperor fish using non-denaturation method, and their physico-chemical and rheological properties were assessed. The myofibrillar proteins of beef, emperor and lamb samples had higher percentage of protein extractability than tuna and chicken samples. The tuna sample showed significantly higher bound bromophenol blue (BPB) value while lamb samples showed lower value (P < 0.05). The myofibrillar protein of chicken sample was found to have more ionic and hydrogen bonds than all other myofibrillar samples. The disulphide bonds in tuna and lamb myofibrillar protein samples were significantly higher than other three samples (P < 0.05). The myofibrillar protein samples showed major bands myosin heavy chain, α-actinin, desimin, actin, troponin, tropomyosin and myosin light chain with wider molecular weight distribution in the range of 20–200 ku. The myofibrillar proteins exhibited Newtonian and shear thickening nature behaviour at lower protein concentration (1 mg/mL) as revealed by flow profile and visco-elastic analysis using rheometer.

Influence of pH, ionic strength and isoascorbic acid on the gel-forming ability of Jumbo squid muscle (Dosidicus gigas)

The effect of pH and ionic strength (μ) on the extraction capacity of myofibrillar proteins from Jumbo squid mantle muscle along with the addition of isoascorbic acid (IA) in its gel-forming ability (GFA) were evaluated. The results indicate that μ had a greater impact (p < 0.05) than pH on the extraction of muscle myofibrillar proteins. The effectiveness of IA, as the precursor of dehydro-isoascorbic acid (DIA), on the oxidation of sulfhydryl groups (–SH) to disulfide bonds (–SS–) of extracted proteins at 0.6 μ was also evaluated. During the sol–gel transition the –SH groups initially present in the protein system decreased (p < 0.05) due to the combined effect of heat treatment (90 °C/30 min) and the addition of IA; however, the oxidative effect of IA reduced (p < 0.05) the GFA of Jumbo squid muscle proteins. Results also indicated that NaCl at 2.8% rather than at 2.5% during gel preparation significantly (p < 0.05) improves its GFA.

Technological Properties of Biodegradable Films Produced with Myofibrillar Proteins Extracted from Gilded cat-fish (Brachyplatystoma rousseauxii) Carcasses and Parings

ABSTRACT This paper aimed to investigate whether the type of fish residue used for extraction of myofibrillar proteins (MP) impacts the technological properties of biodegradable films. The MPs were extracted from two types of Gilded cat-fish (Brachyplatystoma rousseauxii) residues: (1) carcass with muscle attached from the production of mechanically separated meat (MSM) and (2) parings from fillet trimming (PAR). The percentage composition and color of the MPs from MSM (P-MSM) and parings (P-PAR) significantly differed, mainly regarding the ash and lipid contents. The presence of these non-protein compounds in P-MSM led to the formation of films with inferior technological and thermal properties, which indicates the type of residue used impacted the film properties.

The Effect of Specialty Salts on Cooking Loss, Texture Properties, and Instrumental Color of Beef Emulsion Modeling Systems

ObjectivesSalt plays an integral role in meat processing, and reduction or exclusion will have negative impacts on water holding capacity and binding function of protein and fat. Specific to meat emulsions, NaCl is used in the formulation due to its effect on the solubilization (extraction) of myofibrillar meat proteins, which allow the formation and stabilization of the interfacial matrix during manufacture and preparation. While previous research has addressed preservation (shelf-life and oxidation attributes) and flavor (sensory attributes) when using specialty salts in meat products, the application of specialty salts in meat emulsions has never been addressed in a scientific manner. Therefore, the purpose here was to evaluate the incorporation of different levels and types of specialty salts on the physicochemical and textural characteristics of beef emulsions.Materials and MethodsThree specialty NaCl salts (premium sea salt, pink sea salt, and gray sea salt) were added to beef emulsion modeling systems at three different inclusion levels (0.70, 1.00, and 1.30%) and then compared with commercially sourced white salt. Salt (NaCl) purity levels for commercially sourced white salt, premium sea salt, pink sea salt, and gray sea salt were 99.8, 99.8, 95.2, and 94.9%, respectively. Cooking loss, emulsion stability, proximate composition, pH, texture profile analysis, and instrumental color of the emulsions were evaluated with three independent replications from one batch of ground beef. One batch of ground beef was used to properly control for confounding factors such as beef source and day of manufacture. Treatment was applied to one of twelve 500-g base emulsions (without artificial food dyes, preservatives, spices, and seasonings) containing beef (according to the level of salt added), water (28.14%), oil (8.00%), starch (2.00%), and phosphate (0.35%) for each replication (36 total experimental units). Data were analyzed with PROC GLIMMIX of SAS with fixed effects of salt type, salt inclusion level, and their interaction, and the random effect of replication. Least square means were separated using the PDIFF option with a Tukey-Kramer adjustment, and was further separated using an orthogonal set of estimate statements to analyze linear and quadratic effects for salt inclusion level. Differences were considered different at P ≤ 0.05.ResultsEmulsion stability and cooking loss were primarily affected (P &lt; 0.01) by salt inclusion level rather than salt type (P ≥ 0.13). Stability increased and cooking loss decreased as salt inclusion level increased (linear P &lt; 0.01). Proximate composition of cooked meat emulsions trended differently as salt increased from 0.70% to 1.30% salt inclusion level for the different salt types. Moisture increased and lipid decreased for commercial white salt, while moisture decreased, and lipid increased for all three of the specialty salts. Hardness, springiness, gumminess, and chewiness of emulsions increased as the level of salt increased for all the treatments and were greatest (P &lt; 0.0001) in all treatments at the 1.30% salt inclusion level, however, no differences were observed between the salt types.ConclusionOverall, salt inclusion level, rather than salt type, had significant effects on the solubilization of protein and dispersion interactions of the emulsions, which affected physicochemical and functional properties.

Effects of high pressure on biochemical properties and structure of myofibrillar protein from Tegillarca granosa

SummaryThe effects of high‐pressure (HP) treatment parameters (300 MPa for 5 min, 350 MPa for 3 or 5 min and 400 MPa for 1 min) on the biochemical properties and structure of myofibrillar protein (MP) from Tegillarca granosa were investigated. The results showed that HP significantly affected the biochemical properties of MP. Under the HP treatment at 400 MPa for 1 min, the MP extraction yield was reduced from 32.21 to 18.34 mg g−1, and its surface hydrophobicity was increased from 89.29 to 104.69 µg. Ca2+‐ATPase activity of MP decreased from 0.019 to 0.011 µmol (pi) mg−1 (pro) min−1, and both total and reactive sulfhydryl contents significantly declined. Furthermore, HP caused MP to undergo conformational changes. This study provides a reference data for the processing of T. granosa using HP treatment.

Shrimp tropomyosin retains antibody reactivity after exposure to acidic condition.

Although shrimp can be found in certain high acid food matrices, the allergenic capacity of shrimp tropomyosin exposed to low pH condition has not been fully clarified. Thus, a model marinade comprising white vinegar adjusted to different pH was used to determine the effects of acid-induced denaturation on the immunoreactivity of tropomyosin. Whole shrimp experienced either swelling or shrinkage after marination depending on the vinegar pH and the final muscle pH. The extractability of soluble myofibrillar proteins was reduced significantly among shrimp marinated in vinegar at pH 1.0-3.5, and a substantial amount of tropomyosin was retained in the insoluble pellets. Consequently, the immunoglobulin E (IgE)-binding capacity of tropomyosin was significantly lower in the soluble protein fraction of shrimp marinated at pH 1.0-3.5 compared with samples marinated at pH 4.8 and control. However, tropomyosin in the insoluble protein fraction of all marinated shrimp showed strong IgE-binding capacity at all marinating conditions. Thus, tropomyosin in shrimp exposed to low pH condition retained its allergenic capacity owing to the conservation of its linear epitopes. Analysis of the insoluble protein fraction was crucial for the accurate determination of the effect of low pH condition on the immunoreactivity of this allergen. © 2017 Society of Chemical Industry.

Towards generation of bioactive peptides from meat industry waste proteins: Generation of peptides using commercial microbial proteases

Five commercially available food-grade microbial protease preparations were evaluated for their ability to hydrolyse meat myofibrillar and connective tissue protein extracts to produce bioactive peptides. A bacterial-derived protease (HT) extensively hydrolysed both meat protein extracts, producing peptide hydrolysates with significant in vitro antioxidant and ACE inhibitor activities. The hydrolysates retained bioactivity after simulated gastrointestinal hydrolysis challenge. Gel permeation chromatography sub-fractionation of the crude protein hydrolysates showed that the smaller peptide fractions exhibited the highest antioxidant and ACE inhibitor activities. OFFGEL electrophoresis of the small peptides of both hydrolysates showed that low isoelectric point peptides had antioxidant activity; however, no consistent relationship was observed between isoelectric point and ACE inhibition. Cell-based assays indicated that the hydrolysates present no significant cytotoxicity towards Vero cells. The results indicate that HT protease hydrolysis of meat myofibrillar and connective tissue protein extracts produces bioactive peptides that are non-cytotoxic, should be stable in the gastrointestinal tract and may contain novel bioactive peptide sequences.

Understanding tenderness variability and ageing changes in buffalo meat: biochemical, ultrastructural and proteome characterization

Understanding of biological impact of proteome profile on meat quality is vital for developing different approaches to improve meat quality. Present study was conducted to unravel the differences in biochemical, ultrastructural and proteome profile of longissimus dorsi muscle between buffaloes (Bubalus bubalis) of different age groups (young v. old). Higher (P<0.05) myofibrillar and total protein extractability, muscle fibre diameter, and Warner-Bratzler shear force (WBSF) values was observed in old buffalo meat relative to meat from young buffaloes. Scanning electron microscopy photographs revealed reduced fibre size with increased inter-myofibrillar space in young compared with old buffalo meat. Transmission electron microscopy results revealed longer sarcomeres in young buffalo meat relative to meat from old buffaloes. Proteomic characterization using two-dimensional gel electrophoresis (2DE) found 93 differentially expressed proteins between old and young buffalo meat. Proteome analysis using 2DE revealed 191 and 95 differentially expressed protein spots after 6 days of ageing in young and old buffalo meat, respectively. The matrix assisted laser desorption ionization time-of flight/time-of flight mass spectrometry (MALDI-TOF/TOF MS) analysis of selected gel spots helped in identifying molecular markers of tenderness mainly consisting of structural proteins. Protein biomarkers identified in the present study have the potential to differentiate meat from young and old buffaloes and pave the way for optimizing strategies for improved buffalo meat quality.

Rheological and Textural Properties of Sodium Reduced Salt Soluble Myofibrillar Protein Gels Containing Sodium Tri‐Polyphosphate

AbstractThe effect of partial replacement of NaCl (50%) with KCl in the presence of sodium tri‐polyphosphate (STPP) on the cooking loss (CL), water‐holding capacity (WHC), rheological and textural properties of salt soluble myofibrillar proteins (SSMP) gels was investigated. KCl substitution, either alone or in combination with STPP, was found worse than NaCl alone in terms of elasticity of the gels (G′). Both KCl and STPP reduced the CL of the gels. While the gels with replacement of NaCl with KCl had lower (P &lt; 0.05) WHC, addition of STPP to this gels gave rise to similar (P &gt; 0.05) WHC to only NaCl added gels. Substitution of NaCl with KCl resulted in a decrease in hardness of gels whereas STPP addition improved the hardness. Results obtained from the present study suggest that substitution 50% of NaCl with KCl in presence of STPP would be a sound salt reduction alternative in meat systems.Practical ApplicationsSalt is one of the most crucial ingredients affecting meat products functionality. However, recent research has focused on reducing salt in meat products due to its association with some health problems such as hypertension. Reducing sodium chloride (NaCl) decreases extractability of salt soluble myofibrillar proteins (SSMP), thus, negatively affects functional properties of the meat systems. One of the approaches in reducing salt is to replace NaCl with other chloride salts, the most common of which is potassium chloride (KCl). This study focused on determining the effect of partially substituting of NaCl with KCl in the presence of sodium tri‐polyphosphate (STPP) on some functional characteristics of meat SSMP gels. Results indicated that 50% NaCl reduction using KCl and STPP could be achieved with an improvement of textural and functional properties in meat gels. Future research should focus on combined effects of salt substitutes on the rheological and textural characteristics of meat gel systems.

Muscle‐Specific Variation in Buffalo (Bubalus bubalis) Meat Texture: Biochemical, Ultrastructural and Proteome Characterization

AbstractThis study was conducted to unravel the variation in meat quality between tender (psoas major, PM) and less tender (longissimus lumborum, LL) muscles of Indian water buffaloes (Bubalus bubalis). PM and LL were subjected to physicochemical analysis, ultrastructural study and proteome characterization using two‐dimensional gel electrophoresis (2‐DE) and mass spectrometry. Higher (P &lt; 0.05) muscle fiber diameter and Warner–Bratzler shear force was observed in LL, whereas higher (P &lt; 0.05) water‐holding capacity and myofibrillar protein extractability was observed in PM. Transmission electron microscopy revealed higher (P &lt; 0.05) sarcomere length in PM compared with LL. Proteome analysis using 2‐DE revealed 123 differentially abundant proteins in PM and LL. The MALDI‐TOF‐TOF MS analysis of selected protein spots from LL and PM with significant (P &lt; 0.05) differences identified the proteins mainly consisting of calcium‐transporting ATPase.Practical ApplicationsOwing to its low fat, low cholesterol and other healthier attributes, meat produced from water buffaloes has gained increased popularity in several Asian and African countries. Tenderness, which is considered to be the most important attribute of meat quality and a trait highly valued by consumers, varies substantially between muscles. In spite of advancements in optimizing tenderness, an unacceptable level of variation does exist. Findings from the present study illustrate the basis of tenderness variability in psoas major and longissimus lumborum muscles of Indian water buffaloes. Our results indicated complex nature of tenderness development and demonstrated a significant variation in biochemical parameters, ultrastructure and proteome expression. Understanding the variation in texture between muscles is a logical first step to develop strategies for better utilization and for delivering highly palatable product to consumers. This study suggests the necessity to develop muscle‐specific tenderization strategies to minimize the variation between tender and less tender muscles.

Effect of Aging on the Physicochemical, Textural, Microbial and Proteome Changes in Emu (D romaius novaehollandiae ) Meat Under Different Packaging Conditions

The effect of aging on the physicochemical, textural, microbial and proteome characteristics of emu (Dromaius novaehollandiae) meat was studied under aerobic packaging (AP) and vacuum packaging (VP) conditions at 4 ± 1C for 9 and 15 days, respectively. Improvement (P < 0.05) in water-holding capacity, myofibrillar fragmentation index and protein extractability with aging was observed in emu meat cubes under both AP and VP conditions. Reduction (P < 0.05) in Warner-Bratzler shear force values was observed on the 6th and 15th day of aging compared with the 0th day in the AP and VP samples, respectively. The sodium dodecyl sulfate–polyacrylamide gel electrophoresis analysis revealed the appearance of 30-kDa protein bands, indicating extensive proteolysis on the 6th day and 9th day of aging in the AP and VP samples, respectively. Proteome analysis using two-dimensional gel electrophoresis revealed significant (P < 0.01) changes in the number of differentially expressed protein spots in the AP and VP samples during aging. Practical Applications Emus are classified as ratites along with ostriches and rheas and are becoming increasingly popular as a source of low-fat, low-cholesterol, iron-rich red meat alternative. The emu industry is looking for science-based information in order to successfully produce and market emu meat. The present work provides information on emu meat quality, aging process, ultrastructure, proteome characteristics and microbial changes. This paper also discusses about the different packaging methods and the shelf life of emu meat. Considering the increasing demand for new source of animal proteins around the world, this paper provides significant information to all ostrich, rhea and emu meat processors.

Characterization of Myofibrillar Chicken Breast Proteins for Obtain Protein Films and Biodegradable Coatings Generation

Abstract The present work contains studys of extraction and characterization of myofibrillar proteins from chicken breast meat. There were used several methods of extraction of myofibrillar proteins and the protein concentrat myofibrillar was analysed physico-chemical. The current study refers to myofibrillar protein extraction and their characterization, from chicken breast meat. Acid pH dissolution, followed by precipitation at isoelectric pH was used as extraction method. The myofibrillar protein chemical characterization was made by taking into account the functional and rheological properties. Also we study functional properties of concentrate myofibrillar proteins: solubility.,foam capacity and emulsion capacity The results showed that the best method for extraction and characterization of chicken breast myofibrillar proteins is the alkaline pH method. The protein concentrates/isolates, studied by their functional properties, protein solubility and gelling characteristics, can be suitable raw materials for protein films and biodegradable coatings generation

Solubilidad proteica, contenido de mioglobina, color y pH de la carne de pollo, gallina y codorniz

The meat proteins are responsible for diverse characteristics of their derived products. The solubility of the meat proteins can be an index of other important functional properties for the meat processing (as the emulsification), while the myoglobin content influences the meat color. In order to evaluate the solubility of the sarcoplasmic and myofibrillar proteins as well as the myoglobin content in poultry meat, there were obtained chicken, hen and quail carcasses from commercial slaughterhouses; it was applied a completely random design with factorial arrangement 3x2: type of poultry (chicken, hen and quail) and body portion (breast and leg meat), with six treatments, three repetitions in each treatment. There was found interaction in the factors: lightness (L), redness (a), pH, extractability of sarcoplasmic and myofibrillar proteins. The myoglobin content was affected by the body portion and the type of poultry, being higher in the leg than in the breast (0.99 and 0.47 mg/g meat, respectively), the quail had the highest value (1.13 mg/g) and the chicken the lowest value (0.37 mg/g). In all the cases the leg pH was higher than the breast pH. There was a tendency to obtain a higher extractability of the sarcoplasmic proteins from the breast meat, while the myofibrillar proteins were obtained in a higher proportion from the leg portion. The information generated about the characteristics of these poultry meat is novel in Venezuela and can contribute to explain the behavior of these raw materials during the processing activities.

Combined Effect of Ozonized Water Pretreatment and Ozonized Flake Ice on Maintaining Quality of Japanese Sea Bass (Lateolabrax japonicus)

The effect of the combined application of ozonized water pretreatment and ozonized flake ice (O+OIce) as compared with traditional flake ice (CK), ozonized flake ice (OIce), and ozonized water pretreatment and traditional flake ice (O) was investigated for the storage of Japanese sea bass. Microbiological, chemical, and sensory analysis and moisture content were carried out throughout a storage period of 18 days. A slower increase of total viable mesophilic count (TVC), total volatile base nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) was observed for O+OIce as compared with OIce, O, and CK. Treatment of O+OIce also allowed a better control of pH as compared with OIce, O, and CK. None of the treatments resulted in a significant difference in myofibrillar protein extractability and moisture content. The shelf life of Japanese sea bass treated with CK, OIce, O, and O+OIce, determined by sensory evaluation, was 9, 15, 12, and more than 18 days, respectively. Principal component analysis results showed that the treatments significantly affected the fish quality during storage, and the sensory attributes had a significant correlation with TVB-N, TVC, and TBARS. In conclusion, the combined application of ozonized water and ozonized flake ice had the best effect on fish quality maintenance.

Proteomic Analysis and Differential Expression in Protein Extracted from Chicken with a Varying Growth Rate and Water-Holding Capacity

Chickens from a randomly bred genetic line were segregated into high and low growth rates and high and low water-holding capacities (WHCs). The objective of this study was to identify protein markers associated with slow and fast growth rates and low and high WHCs from water-soluble protein (WSP) and crude myofibrillar protein (CMP) extracts of chicken breast muscle. Proteins were fractionated using two-dimensional electrophoresis, and a total of 22 protein spots were selected, excised, and analyzed by in-gel tryptic digestion and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Proteins expressed in extracts from slow and fast growth rates and low and high WHCs included metabolic enzymes, such as creatine kinase, pyruvate kinase, triosephosphate isomerase, and ubiqitin; housekeeping proteins, such as heat shock protein; contractile proteins, such as myosin heavy chain; actin; and also MHC isoforms and actin isoforms. The mass spectra of 20 protein spots significantly matched (protein score >83; P < 0.05) an online database. In CMP, there were unique proteins that were present only in the fast-growth population: gi|118099530 , gi|20664362 , gi|71895043 , gi|114794125 , gi|297343122 , and gi|71895043 . This information identified protein markers associated with growth rate and water holding capacity. Some of those protein markers could be added to the chicken database.