Ultrasound and meat quality: A review

The positive contribution of ultrasound technology in muscle food key processing and its mechanism-a review

Traditional processing methods can no longer meet the demands of consumers for high-quality muscle food. As a green and non-thermal processing technology, ultrasound has the advantage of improving processing efficiency and reducing processing costs. Of these, the positive effect of power ultrasound in the processing of muscle foods is noticeable. Based on the action mechanism of ultrasound, the factors affecting the action of ultrasound are analyzed. On this basis, the effect of ultrasound technology on muscle food quality and its action mechanism and application status in processing operations (freezing-thawing, tenderization, marination, sterilization, drying, and extraction) is discussed. The transient and steady-state effects, mechanical effects, thermal effects, and chemical effects can have an impact on processing operations through complex correlations, such as improving the efficiency of mass and heat transfer. Ultrasound technology has been proven to be valuable in muscle food processing, but inappropriate ultrasound treatment can also have adverse effects on muscle foods. In the future, kinetic models are expected to be an effective tool for investigating the application effects of ultrasound in food processing. Additionally, the combination with other processing technologies can facilitate their intensive application on an industrial level to overcome the disadvantages of using ultrasound technology alone.

Ultrasound promoted green synthesis, anticancer evaluation, and molecular docking studies of hydrazines: a pilot trial

We reported herein an efficient, environmentally friendly synthesis of hydrazine carboxamides (6a-l) in a water-glycerol (6:4) solvent system using ultrasonic irradiation. Ultrasonicated reactions were found to be much faster and more productive than conventional synthesis. The prepared compounds (6a-l) were tested against nine panels of 60 cancer cell lines according to the National Cancer Institute (NCI US) protocol. N-(4-Chlorophenyl)-2-(2-oxoindolin-3-ylidene)hydrazine-1-carboxamide (6b) was discovered to be promising anticancer agents with higher sensitivity against CCRF-CEM, HOP-92, UO-31, RMPI-8226, HL-60(TB), and MDA-MB-468 with percent growth inhibitions (%GIs) of 143.44, 33.46, 33.21, 33.09, 29.81, and 29.55 respectively. Compounds (6a-l) tested showed greater anticancer activity than Imatinib, except for compound 6k. Compounds 6b and 6c were found to be lethal on the CCRF-CEM leukaemia cell line, with %GIs of 143.44 and 108.91, respectively. Furthermore, molecular docking analysis was performed to investigate ligand binding affinity at the active site of epidermal growth factor (EGFR).

Bacterial nitric oxide synthase in colorizing meat products: Current development and future directions

Nitrite has been widely used in meat products for its abilities including color formation, antimicrobial properties, flavor formation and preventing lipid oxidation. However, the possible generation of N-nitrosamines through reaction of nitrite with secondary amines arises many concerns in the usage of nitrite. For a long time, nitrite substitution is unsettled issue in the meat industry. Many attempts have been tried, however, the alternative solutions are often ephemeral and palliative. In recent years, bacterial nitric oxide synthase (bNOS) has received attention for its critical roles, especially in reddening meat products. This comprehensive background study summarizes the application of bNOS in colorizing meat products, its functions in bacteria, and methods of regulating the bNOS pathway. Based on this information, some strategies for promoting the nitric oxide yield for effectively substituting nitrite are presented, such as changing the environmental conditions for bacterial survival and adding substrate. Thus, bNOS is a promising nitrite substitute for color formation, and further research on its other roles in meat needs to be carried out to obtain the complete picture.

Effects of ultrasound-assisted thawing on lamb meat quality and oxidative stability during refrigerated storage using non-targeted metabolomics

The aim of this study was to evaluate the changes of ultrasound-assisted thawing on lamb meat quality and differential metabolite profiles during refrigerated storage. Compared with flow water thawing (FW), pH, a*, C*, and sulfhydryl content of lamb were significantly increased, while L*, drip loss and cooking loss were significantly decreased after ultrasound-assisted thawing (UT). On day 1 (UT1 and FW1) and day 7 (UT7 and FW7) in the UT and FW groups, principal component analysis explained 42.22% and 39.25% of the total variance. In this study, 44 (UT1 and FW1) and 47 (UT7 and FW7) differentially expressed metabolites were identified, including amino acids, carbohydrates and their conjugates, nucleic acids, carbonyl compounds and others. The results of this study provide data to clarify the differences between UT and FW, and lay a foundation for the application of ultrasound-assisted thawing in the meat industry.

Physicochemical Properties and Young Adult Consumer Preference of Dry-Aged Beef after High-Intensity Ultrasonication

This study aimed to determine the effect of high-intensity ultrasound (HIU. F = 37 kHz, I = 28W/cm2, bath for 30 min, 5 °C) on physicochemical characteristics and sensorial preference of seven aged (23 d ageing) bovine muscles (L. dorsi lumborum, L. dorsi thoracis, Psoas major, Semimembranosus, Biceps femoris, Rectus femoris, and Gluteus medius). Muscles were randomly distributed in two treatments: with and without ultrasonication. Colour (L*, a*, b* and C*), water-holding capacity (WHC), and shear force (N) were determined before and after simulated retail display (SRD) in modified atmosphere packing (MAP; 75% O2: 25% CO2, 3 °C, 13 h led light exposition) for 5 d. Sensorial toughness was also evaluated at the end of the SRD. Ultrasonication slightly reduces 6–9% WHC of beef. HIU did not affect (p ˃ 0.05) water loss, meat colour, shear force and sensorial toughness of the meat. The Semimembranosus was the toughest muscle. Ultrasonication of 23-day-aged beef did not show improvements on quality characteristics, and despite minor changes in water loss and slight increase in shear force, consumers did not detect differences.

Insights into ultrasonic treatment on the mechanism of proteolysis and taste improvement of defective dry-cured ham

To investigate the effects of ultrasonic treatment on proteolysis and taste development of defective dry-cured ham, sensory attributes, enzyme activities, protein degradation and free amino acids were evaluated after different ultrasonic treatments. The ultrasonic treatment of 1000 W & 50 °C significantly increased the intensities of overall taste, umami, sweetness and richness, and decreased bitterness values compared with other groups. The residual activities of DPP I and cathepsin B + L in 1000 W & 50 °C maintained 48.71% and 24.94% of control group, respectively; the intense degradation of structural proteins was observed by label-free proteomics, accordingly. The contents of total free amino acids from 4522.64 mg/100 g muscles in control group increased to 5838.75 mg/100 g muscles in 1000 W & 50 °C; the largest increase of sweet and umami amino acids observed in 1000 W & 50 °C was responsible for the improvement of taste quality of defective dry-cured ham.

Effect of ultrasound-assisted sodium bicarbonate treatment on gel characteristics and water migration of reduced-salt pork batters

To study the potential usefulness of ultrasound (0, 30, and 60 min) and sodium bicarbonate (0 % and 0.2 %) combination on the reduced-salt pork batters, the changes in water holding capacity, gel properties, and microstructure were investigated. The pH, salt-soluble proteins solubility, cooking yield, and b* values of reduced-salt pork batters significantly increased (P < 0.05) with the increase in ultrasound time and the addition of sodium bicarbonate, leading to the hardness, springiness, cohesiveness, and chewiness significantly increased (P < 0.05). Furthermore, the use of ultrasound-assisted sodium bicarbonate treatment caused the reduced-salt pork batters to form a typical spongy structure with more evenly cavities. Due to the initial relaxation time of T₂₁ and T₂₂ were shorter, and the peak ratio of P₂₁ was increased and P₂₂ was decreased after ultrasound-assisted sodium bicarbonate treatment, implying that the mobility of water was reduced. Thus, the use of ultrasound-assisted sodium bicarbonate treatment enabled reduced-salt pork batters to have better gel characteristics and higher cooking yield.

Impact of ultrasonication applications on color profile of foods

Food color is a feature that provides preliminary information about their preference or consumption. There are dominant pigments that determine the color of each food; the most important pigments are anthocyanins (red-purple color), chlorophylls (green color), carotenoids (yellow-orange color), and betalains (red color). These pigments can be easily affected by temperature, light, oxygen, or pH, thereby altering their properties. Therefore, while processing, it is necessary to prevent the deterioration of these pigments to the maximum possible extent. Ultrasonication, which is one of the emerging non-thermal methods, has multidimensional applications in the food industry. The present review collates information on various aspects of ultrasonication technology, its mechanism of action, influencing factors, and the competence of different ultrasonication applications (drying, irradiation, extraction, pasteurization, cooking, tempering, etc.) in preserving the color of food. It was concluded that ultrasonication treatments provide low-temperature processing at a short time, which positively influences the color properties. However, selecting optimum ultrasonic processing conditions (frequency, power, time, etc.) is crucial for each food to obtain the best color. The key challenges and limitations of the technique and possible future applications are also covered in the paper, serving as a touchstone for further research in this area.

Advances in application of ultrasound in meat tenderization: A review

Tenderness could measure the eating quality of meat. The mechanism of muscle tenderization is becoming more and more critical in the past decade. Since the transforming of muscle into edible meat requires a complex physiological and biochemical process, the related tenderization of meat can be beneficial to improving the meat quality. As a non-thermal processing technology with energy-saving, environmental protection, and intense penetration, ultrasonic treatment has been widely used in the tenderizing process of meat products. In this paper, the principle of meat tenderization, the ultrasonic technology, and the application of ultrasonic technology in meat tenderization is summarized. The effect of ultrasonic technology on the tenderization of meat products is discussed from different perspectives (muscle fibers and connective tissue properties).

Insight into Ultrasound-Induced Modifications of the Proteome and Flavor-Related Proteins of Unsmoked Bacon by Applying Label-Free Quantitation Technology

The aim of this study was to investigate the modifications of the proteome and flavor-related proteins in unsmoked bacon resulting from ultrasound treatment with the application of label-free quantitation technology together with bioinformatics analysis. Results showed that the expression levels of 137 proteins were markedly affected by ultrasound with most of them being significantly upregulated. The proteins distributed in the cytoplasm and the cytosol, the mitochondrion, and the nucleus were more susceptible to ultrasound treatment. Meanwhile, 20 flavor-related proteins, mostly myofibrillar proteins and metabolic enzymes mainly involved in the metabolic pathways of signaling and cellular processes and environmental information processing, were screened out. In addition, the differential expressions of flavor-related proteins induced by ultrasound were verified by western blotting. This study displayed insightful information from the proteomics perspective for a better understanding of the influential effect of ultrasound treatment on meat flavor.

Effect of high-power ultrasound and bamboo fiber on the technological and oxidative properties of phosphate-free meat emulsions

The combination of high-power ultrasound (HPU) and bamboo fiber (BF) was investigated as a strategy to produce phosphate-free meat emulsions. The samples were made with the addition of 0 and 0.25% of alkaline phosphate and 0, 2.5, and 5% BF. Immediately after filling, the samples were sonicated for 0 or 27 min at normal mode, 25 kHz, 60% amplitude, and 20 °C. The samples made with BF and without phosphate showed higher emulsion stability compared to the control made with phosphate. The addition of 2.5% BF effectively compensated for the texture changes due to the absence of phosphate. HPU improved the effect of BF on the texture of meat emulsions by increasing cohesiveness. No significant impact of HPU and BF was observed on the oxidative quality of the samples. However, the instrumental assays and the sensory evaluation demonstrated that the absence of phosphate increased the lipid oxidation of the samples from the beginning of storage.

Tandem mass tag-based proteomics analysis of protein changes in the freezing and thawing cycles of Trachurus murphyi

We investigated the proteome variations in Trachurus murphyi with different cycles of freezing and thawing (FT) under frozen storage. A total of 2,482 proteins were assessed quantitatively, of which 269 proteins were recognized as differential abundance proteins during the second FT cycle until the eighth FT cycle. Bioinformatics analysis on gene ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway analyses of Differential Analysis of Proteins (DAPs) indicated multiple DAPs engaged with the protein structure, metabolic enzymes, and protein turnover. In addition, some of the observed proteins were probably the underlying markers of protein oxidation (PO). The analysis of PO sites revealed the sites of PO, such as amino adipic semialdehydes, γ-glutamic semialdehydes, and Schiff bases. Bioinformatics analyses demonstrated the involvement of differentially expressed proteins in the Hippo signaling pathway (Ko04390), indicating strong protein degradation with greater numbers of FT cycles under frozen storage. It provides an insight into quality stability from a proteomics quality perspective at the molecular level. The results obtained have deepened our current understandings of the mechanisms that reveal variations in proteomes and quality, as well as help promote quality control of T. murphyi across the cold transportation chain. PRACTICAL APPLICATION: Temperature fluctuation is one of the core issues during frozen food storage and distribution faced by the frozen food industry. Fluctuation may result in microstructural changes, ice recrystallization, and protein change in frozen food products. Tandem mass tag-based methods were adopted to study proteome variations in Trachurus murphyi muscles under different cycles of freezing and thawing under frozen storage conditions in this paper. The results obtained have deepened our current understandings of the mechanisms that reveal variations in proteomes and quality, as well as help promote quality control of T. murphyi across the cold transportation chain.

Application of ultrasound-assisted cryoprotectant impregnation for improving the storage quality of snakehead fish fillets

In aquatic products companies, saccharides and phosphates are often used to impregnate products to improve their quality. Insignificant impregnation effect is a main problem met in the impregnation process. The effect of ultrasonic-assisted impregnation on the storage quality of snakehead fish fillets at -18°C was studied. For all samples, such parameters as water holding capacity, pH value, salt-soluble protein content, whiteness and cooking loss rate were examined periodically. Furthermore, the changes of moisture distribution and migration in snakehead fish fillets during storage were investigated using low-field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI). The results demonstrated that ultrasonic-assisted impregnation showed better anti-freeze and water holding capacity effects than that of cryoprotectant impregnation alone. Therefore, ultrasonic treatment could be used as an effective way to improve the quality of snakehead fish fillets during the frozen process. This study could provide a broad application prospect in aquatic product processing industry.

Natural alternatives for processed meat: Legislation, markets, consumers, opportunities and challenges

Consumers' interest in food with less and/or free from synthetic additives has increased considerably in recent years. In this context, researchers and industries have concentrated efforts on developing alternatives to these compounds. Replacing synthetic additives in meat products is a challenge, given their importance for sensory characteristics and food safety. Complementary technologies combined with the replacement and/or reduction of synthetic additives (hurdle technologies) has been studied focusing on the protection and extension of the shelf life of meat products. This review reports alternatives for replacing and/or reducing the use of synthetic additives in meat derivatives, aiming at the development of more natural and simpler meat products, familiar to consumers and considered clean labels.

Power ultrasound in the meat industry (freezing, cooking and fermentation): Mechanisms, advances and challenges

High intensity ultrasound (HIUS) has a wide range of applications in different sectors of food processing. It is a promising and emerging technology demonstrating the potential to promote food processes without or at least damage to the quality of products. Among the processes of the meat industry, freezing, thawing, cooking and fermentation are very sensitive and important, because they have significant effects on product quality and are also very energy and time consuming. This review paper provides an interpretation of high intensity ultrasound (HIUS) applications, a summary of recent outstanding published research and an overview of the freezing/thawing, cooking/frying and fermentation processes in meat and its products assisted by HIUS. The effects, benefits and drawbacks as well as the challenges ahead in the commercialization of this technology in the meat industry are studied. The research results confirmed that the use of HIUS in the meat freezing/thawing, cooking/frying and fermentation in combination with the corresponding processing methods demonstrates a great potential to promote the process, improve the general quality of the final product and reduce the time and energy required. However, many issues remain that require further research to address these challenges. These challenges and subsequent research that is useful for developing and increasing the efficiency of this technology have been reviewed. After the literature review, it is concluded that HIUS may be a useful technology for meat processing because of its significant effects on the quality factors and related process variables that leads to the preservation of the initial nutritional and sensory properties of meat and its products. Of course, research must be continued to eliminate the disadvantages or minimize the undesirable effects of this technology on the final product and to remove barriers to commercialization and optimization of this method.

Evaluation of effects of ultrasound-assisted saucing on the quality of chicken gizzards

The purpose of this study was to evaluate the effects of ultrasound-assisted saucing on the quality of chicken gizzards. The results showed that with the prolonging of the saucing time, the yield, water holding capacity (WHC), lightness (L*), redness (a*) and springiness of chicken gizzards significantly decreased, while the shear force, hardness and chewiness significantly increased (P < 0.05). When the saucing time was the same, the yield, WHC, springiness and tenderness of the ultrasound group were significantly higher than those of the non-ultrasound group (P < 0.05). In particular, when the saucing time was 30 min, the yield, WHC and springiness of the ultrasound group increased by 2.13%, 0.97% and 10.53%, and the shear force decreased by 21.22% compared with those of the non-ultrasound group, respectively. Besides, ultrasound pretreatment increased the content of aromatic compounds, short-chain alkanes, alcohols, aldehydes and ketones, and the principal component analysis displayed that C-50 (saucing for 50 min without ultrasound pretreatment) and U-30 (saucing for 30 min with ultrasound pretreatment) were similar in flavor. Therefore, ultrasound pretreatment is a potential way to improve the quality of saucing chicken gizzards and shorten the processing time.

Improving the poor texture and technological properties of chicken wooden breast by enzymatic hydrolysis and low-frequency ultrasound

Abstract

Wooden breast (WB) is a recurrent myopathy in fast‐growing birds, which alters the appearance, functionality, and the texture of the breast muscle. The objectives of this study were (i) to evaluate the effect of a combined use of papain enzyme and ultrasound on the texture of WB chicken using response surface methodology and (ii) to assess the effect of marinating on the quality of WB chicken meat. Full factorial experimental design method was used to obtain the ideal conditions to soften the WB meat. The independent variables were the concentration of papain (0.1%–0.3%) and the time in ultrasonic bath (10–30 min); shear force (SF) was the dependent variable. The optimum results were obtained at a concentration of 0.2% papain and 20 min on ultrasound. Papain enzyme had a great influence on the texture of WB meat, reducing its hardness. However, the effect of the ultrasound time on the SF response was not observed. The marinated WB meat showed similar SF values and texture profile than those from normal (N) meat, with reduction in the parameters of protein and lipid oxidation. The use of papain without ultrasound bath proved to be an efficient means for improving the tenderness of WB breasts.

Practical Application

This study shows the efficiency of the application of two technological procedures (enzymatic treatment and ultrasound) to improve the texture profile and technological properties of chicken breasts affected by the wooden breast myopathy. The economic loss caused by the world‐wide occurrence of wooden breast is enormous, and the application of papain has been found to counteract the impaired properties of this abnormal chicken breasts. Since papain is already widely used in the food industry to tenderize meat, its application in improving the quality of WB meat is straightforward.

Effect of Lentinan on Lipid Oxidation and Quality Change in Goose Meatballs during Cold Storage

The effects of different concentrations of lentinan (LNT) (0, 0.5, 1, 2 and 4%) on the oxidation characteristics and physicochemical properties of goose meatballs were investigated during different cold storage (4 °C) stages (3, 7 and 12 days). After adding LNT, the thiobarbituric acid reactive substances (TBARS) and total volatile base nitrogen (TVB-N) of goose meatballs significantly decreased compared to the LNT-free sample during cold storage, which indicated that LNT can inhibit the fat oxidation and the release of nitrogenous substances. Meanwhile, the presence of LNT makes microstructure of the goose meatball samples become denser during the whole storage time. The headspace solid phase microextraction gas chromatography-mass spectrometry (SPME-GC-MC) results showed that the proportion of aldehydes in the 4% LNT group reached 0 during storage, suggesting that high LNT concentration inhibits the formation of oxidized products in meat products. The sensory evaluation showed that the addition of LNT improved the color, appearance, flavor, and overall acceptance of goose meatballs, and the 2% LNT group had the highest score in overall acceptance. In summary, the addition of LNT could delay lipid oxidation and improve the quality of goose meatballs during cold storage.

Comparison of calcium and ultrasonic treatment on fruit firmness, pectin composition and cell wall-related enzymes of postharvest apricot during storage

This study was conducted to examine the effects of calcium treatment (2%, 20 min) and ultrasonic treatment (400 W, 20 min) on postharvest apricot fruit during storage. The results showed that after calcium and ultrasonic treatment, compared with the control, the firmness of apricot fruit increased by 41.53% and 3.83% at 16 d, but juice yield and water-soluble pectin (WSP) content decreased by 8.26% and 3.55%, 28.57% and 4.08%, respectively. Both calcium and ultrasonic treatment were more effective in reducing polygalacturonase (PG), β-Galactosidase (β-Gal), pectin methylesterase (PME), polyphenol oxidase (PPO) and peroxidase (POD) activity. Moreover, fruit firmness was significantly negatively correlated with juice yield, WSP and PPO, and positively correlated with PG and β-Gal, PPO and POD. In contrast, calcium treatment was more effective than ultrasonic treatment in delaying postharvest softening of apricot.

Evaluation of ultrasound-assisted L-histidine marination on beef M. semitendinosus: Insight into meat quality and actomyosin properties

This paper aimed to evaluate the effects of ultrasound-assisted L-histidine marination (UMH) on meat quality and actomyosin properties of beef M. semitendinosus. Our results found that UMH treatment effectively avoided excessive liquid withdrawal, and disrupted myofibril integrity by modifying the water distribution and weakening connection of actin-myosin with increased muscle pH. The ultrasound-treated sample provided more opportunity for the filtration of L-histidine to intervene the isoelectric point and conformation of muscle protein. The activated caspase-3 and changes of ATPase activity in UMH-treated meat accelerated the postmortem ageing, and L-histidine might competitively inhibit the actin-myosin binding by the imidazole group. UMH decreased the surface hydrophobicity by shielding hydrophobic area and unfolding the actomyosin structure. In addition, the increased actomyosin solubility with smaller particle size enhanced the SH content for better cross-linking of myosin tail, and formation of heat-set gelling protein structure. Therefore, UMH treatment manifested the potential to improve beef quality.

New insights into the ultrasound impact on covalent reactions of myofibrillar protein

In this work, two different covalent reactions, namely, alkaline reaction and free radical oxidation, were selected to compare the difference in the strengthening effects of ultrasound treatment (UDT). The grafting effects were verified by protein electrophoresis and bound gallic acid (GA) assay. Furthermore, non-covalent interactions between myofibrillar protein (MPN) aggregates were destroyed by UDT, as proved by the lower particle sizes and higher ζ-potential. Comparatively, the results from tertiary structure index and circular dichroism revealed UDT-assisted free radical oxidation could lead to better conjugates with greater structural properties. The atomic force microscope (AFME) and protein flexibility showed that MPNs appeared to display as irregular spherical particles after alkaline reaction, however, maintained fibrous structure during the free radical oxidation. Consequently, the combination of UDT and free radical oxidation were more effectively for strengthening the influence of acoustic cavitation on MPNs, of which mechanism was the changes in viscosity properties, microstructure and acoustic cavitation radicals.

Effect of Ultrasound Treatment on Barrier Changes of Polymers before and after Exposure to Food Simulants

In this study, we investigated the impact of ultrasound treatment on barrier properties of linear low-density polyethylene (LLDPE) and acrylic/poly(vinylidene chloride) polypropylene (PPAcPVDC)-coated pouches intended for food packaging before and after exposure to food simulants. Packaging pouches were filled with two food simulants, namely ethanol (10% (v/v)) and acetic acid (3% (w/v)), in order to simulate food−packaging interaction and possible compound migration from packaging materials. Samples were subjected to an ultrasound water bath treatment for 5 min, 15 min, and 30 min at 60 °C (±2 °C) and with an amplitude of 100% as an equivalent to the heat-treatment conditions combined with an ultrasound effect. Furthermore, the effect of temperature on the polymer barrier (water vapour and oxygen permeability) properties was tested at 20 °C, 40 °C, and 60 °C. Results showed that PPAcPVDC possessed better properties of water vapour permeability and oxygen permeability properties to LLDPE. Statistical analyses showed a significant (p < 0.001) impact of ultrasound treatment on the overall migration value, regardless of the food simulant used.

Role of Food Hydrocolloids as Antioxidants along with Modern Processing Techniques on the Surimi Protein Gel Textural Properties, Developments, Limitation and Future Perspectives

Texture is an important parameter in determining the quality characteristics and consumer acceptability of seafood and fish protein-based products. The addition of food-based additives as antioxidants (monosaccharides, oilgosaccharides, polysaccharides and protein hydrolysates) in surimi and other seafood products has become a promising trend at an industrial scale. Improvement in gelling, textural and structural attributes of surimi gel could be attained by inhibiting the oxidative changes, protein denaturation and aggregation with these additives along with new emerging processing techniques. Moreover, the intermolecular crosslinking of surimi gel can be improved with the addition of different food hydrocolloid-based antioxidants in combination with modern processing techniques. The high-pressure processing (HPP) technique with polysaccharides can develop surimi gel with better physicochemical, antioxidative, textural attributes and increase the gel matrix than conventional processing methods. The increase in protein oxidation, denaturation, decline in water holding capacity, gel strength and viscoelastic properties of surimi gel can be substantially improved by microwave (MW) processing. The MW, ultrasonication and ultraviolet (UV) treatments can significantly increase the textural properties (hardness, gumminess and cohesiveness) and improve the antioxidative properties of surimi gel produced by different additives. This study will review potential opportunities and primary areas of future exploration for high-quality surimi gel products. Moreover, it also focuses on the influence of different antioxidants as additives and some new production strategies, such as HPP, ultrasonication, UV and MW and ohmic processing. The effects of additives in combination with different modern processing technologies on surimi gel texture are also compared.

Technological and morphological characteristics of acoustically assisted frozen “foie gras” (fattened duck liver)

The aim of this work was to explore the changes in morphology, pH and color characteristics (L*, a*, b*) in AEF (Acoustic Extra Freezing) frozen fatty duck liver “foie gras” (LA) after 18 months of frozen storage (-18°C). The cooled fattened duck liver (0 -4°C) was processed with acoustic assisted pre-massage step for 20 min, followed by AEF freezing at -25°C until reaching -18°C in the center of the product. The conventionally air frozen “foie gras” (air temperature -35°C) were used as control (LK). The type of freezing did not affect significantly on the pH of the tested samples (p ≥ 0.05). The changes in the instrumentally measured color characteristics (L*, a*, b*) in AEF frozen “foie gras” were found lower (p ≤ 0.05) compared to LK. The light microscopy of LK frozen “foie gras” showed large ice crystals formation and significant destructive changes in muscles. After AEF freezing, the cell structure was better preserved, and histologically similar to fresh “foie gras”.

Improvement of gelation properties of silver carp surimi through ultrasound-assisted water bath heating

The present work investigated the effects of water bath heating coupled with different ultrasound treatments on the gel properties, protein conformation, microstructures and chemical interactions of silver carp surimi at low/high salt levels. Results showed that the gel strength, hardness, springiness and water holding capacity (WHC) of surimi gels at low salt concentration were inferior to those at high salt content, regardless of the treatments. Compared with the traditional water bath heating, ultrasonic-assisted treatments significantly improved the gelation properties of surimi at the same salt level. In fact, ultrasound treatment also facilitated the unfolding of α-helix structure of the protein, with the resulting exposure of internal groups further enhancing hydrophobic interactions and hydrogen bonds between protein molecules, thereby leading to the formation of denser microstructures with smaller holes. Furthermore, the most noteworthy ultrasonic treatment group was ultrasound-assisted preheating (U + W) group, whose gelation performance under low salt condition, was comparable with that of the traditional two-stage heating (W + W) group with high salt content. Overall, ultrasound-assisted water bath preheating proved to be a feasible approach to improve the gel properties and microstructures of low-salt surimi gels.

Effect of ultrasound application on the growth of S. xylosus inoculated in by-products from the poultry industry

A wide variety of by-products are produced by the industry when animals are slaughtered. However, the proteins present in these by-products, are not being fully useable, in the elaboration of value-added products. Staphylococcus xylosus is commonly used as a starter culture in meat products subjected to ripening for a long period, as it produces proteolytic and lipolytic enzymes that improve the sensory quality of the products. Ultrasound (US) has been arousing interest in the meat industry, as it reduces processing time and also improves the technological and sensory quality of meat products. However, the stimulate effect of US on the growth of S. xylosus in by-products from the poultry industry is still unknown. Thus, this study aimed to evaluate the stimulate effect of US on the growth of S. xylosus inoculated in by-products from the poultry industry. S. xylosus was inoculated (5.63 log CFU/g) in sterilized by-products from the poultry, which were then sonicated at 37 °C for 0, 15, 30, and 45 min according to the following parameters: frequencies of 130 and 35 kHz, amplitudes of 50% and 80% and normal and degas operating modes. The sonicated samples were incubated at 37 °C for 0, 24, 48, and 72 h. Soon after sonication, no stimulate effect of US was observed on the growth of S. xylosus. However, after 24 h of incubation, the samples sonicated for 15 and 30 min in normal mode, at 35 and 130 kHz, and amplitudes of 50 and 80% exhibited better stimulate effect at the growth S. xylosus counts (p < 0.01) when compared to the Control, with values of 8.23 and 7.77 log CFU/g, respectively. These results can be exploited to obtain new added-value products, having as raw material by-products from the poultry industry.

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We studied the effect of US on the growth of S. xylosus in poultry waste.

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Frequency, amplitude and US time had a great impact on the growth of S. xylosus.

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Constant ultrasonic waves stimulated the growth of S. xylosus.

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This study found a promising new field of application for US in the meat industry.

The Physicochemical, Microbiological, and Structural Changes in Beef Are Dependent on the Ultrasound System, Time, and One-Side Exposition

The effect of high-intensity ultrasound (HIU) system (bath, 37 kHz and 90 W/cm2; or probe, 24 kHz and 400 W) and application time (25 or 50 min, one-side exposition) on the properties of bovine Longissimus lumborum after 7 d of storage at 4 °C was studied. The bath system significantly increased the lightness of the muscle, while other color parameters (a*, b*, hue, and chroma) were not different from the control. The water holding capacity and shear force decreased significantly (3.1-5% and 0.59-0.72 kgf, respectively) in sonicated meat independently of the system, favoring the tenderization of the muscle after storage. Microstructural changes observed in the HIU-exposed surface provided evidence of a higher area of interfibrillar spaces (1813 vs. 705 µm2 in the control), producing tenderization of the muscle, compared with the control. HIU significantly increased counts of total aerobic and coliform bacteria, especially after 50 min of ultrasonication. HIU also increased lactic acid bacterial counts in the bath system. Single-sided muscle exposition to ultrasound may produce sufficient significant changes in muscle properties, which could decrease long treatment times that would be needed for the exposition of both sides. HIU in bath systems increases tenderness by modifying meat ultrastructure, with no significant changes in physicochemical parameters. Nevertheless, microbiological quality may need to be considered during the process due to a slight increase in bacterial counts.

Recent advances in the development of healthier meat products

Meat products are an excellent source of high biological value proteins, in addition to the high content of minerals, vitamins, and bioactive compounds. However, meat products contain compounds that can cause a variety of adverse health effects and pose a serious health threat to humans. In this sense, this chapter will address recent strategies to assist in the development of healthier meat products. The main advances about the reduction of sodium and animal fat in meat products will be presented. In addition, strategies to make the lipid profile of meat products more nutritionally advantageous for human health will also be discussed. Finally, the reduction of substances of safety concern in meat products will be addressed, including phosphates, nitrites, polycyclic aromatic hydrocarbons, heterocyclic aromatic amines, as well as products from lipid and protein oxidation.

Enzymatic probe sonication for quick extraction of total bisphenols from animal-derived foods: Applicability to occurrence and exposure assessment

A high demand exists in bisphenols (BPs) screening studies for quick, reliable and straightforward analytical methods that generate data faster and simultaneously. Herein, we describe a combination of enzymatic probe sonication (EPS) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for quick extraction and simultaneous quantification of eight important BPs in animal-derived foods. Results obtained demonstrated that the ultrasonic probe power could not only enhance the enzymatic hydrolysis efficiency, but also accelerate the liquid-liquid extraction procedure. Under optimized EPS parameters, one sample could be exhaustively extracted within 120 s, as compared with 12 h needed for the conventional enzymatic extraction which is more suitable for high-throughput analysis. The method was successfully applied to analyze residual BPs in animal-derived foods collected from Beijing, China. Widespread occurrence of BPA, BPS, BPF, BPAF, BPP, and BPB were found, with detection frequencies of 65.2%, 42.4%, 33.7%, 29.4%, 28.3%, and 27.2%, respectively. The highest total concentration levels of BPs (sum of the eight BPs analyzed, ΣBPs) were found in chicken liver (mean 12.2 μg/kg), followed by swine liver (6.37 μg/kg), bovine muscle (3.24 μg/kg), egg (2.03 μg/kg), sheep muscle (2.03 μg/kg), chicken muscle (1.45 μg/kg), swine muscle (1.42 μg/kg), and milk (1.17 μg/kg). The estimated daily intake (EDI) of BPs, based on the mean and 95th percentile concentrations and daily food consumptions, was estimated to be 5.687 ng/kg bw/d and 22.71 ng/kg bw/d, respectively. The human health risk assessment in this work suggests that currently BPs do not pose significant risks to the consumers because the hazard index (HI) was <1.

Novel Techniques for Microbiological Safety in Meat and Fish Industries

The consumer tendency towards convenient, minimally processed meat items has placed extreme pressure on processors to certify the safety of meat or meat products without compromising the quality of product and to meet consumer’s demand. This has prompted difficulties in creating and carrying out novel processing advancements, as the utilization of more up-to-date innovations may influence customer decisions and assessments of meat and meat products. Novel advances received by the fish and meat industries for controlling food-borne microbes of huge potential general wellbeing concern, gaps in the advancements, and the requirement for improving technologies that have been demonstrated to be effective in research settings or at the pilot scale shall be discussed. Novel preparing advancements in the meat industries warrant microbiological approval before being named as industrially suitable alternatives and authorizing infra-structural changes. This miniature review presents the novel techniques for the microbiological safety of meat products, including both thermal and non-thermal methods. These technologies are being successfully implemented and rationalized in subsisting processing surroundings.

An overview of tropomyosin as an important seafood allergen: Structure, cross-reactivity, epitopes, allergenicity, and processing modifications

Tropomyosin (TM) is a major allergen in crustaceans, which often causes allergy and is fatal to some consumers. Currently, the most effective treatment is to avoid ingesting TM, although most adverse events occur in accidental ingestion. In this review, the molecular characterization, epitopes, cross-reactivity, and pathogenesis of TM are introduced and elucidated. Modification of TM by traditional processing methods such as heat treatment and enzymatic hydrolysis, and innovative processing technologies including high-pressure treatment, cold plasma (CP), ultrasound, pulsed electric field (PEF), pulsed ultraviolet, microwave and irradiation are discussed in detail. Particularly, enzymolysis, PEF, and CP technologies show great potential for modifying TM and more studies are needed to verify their effectiveness for the seafood industry. Possible mechanisms and the advantages/disadvantages of these technologies for the mitigation of TM allergenicity are also highlighted. Further work should be conducted to investigate the allergenicity caused by protein segments such as epitopes, examine the interaction sites between the allergen and the processing techniques and reveal the reduction mechanism of allergenicity.

Effects of three treatments on protein structure and gel properties of Perccottus glenii myofibrillar protein

In order to improve Perccottus glenii myofibrillar protein (MP) gel properties, three treatments were evaluated: ultrasonic, transglutaminase (TGase) and combined ultrasonic-transglutaminase treatments. Combined ultrasonic-transglutaminase treatment altered protein structure and gel properties most dramatically. As compared with untreated control group protein, treated protein gels possessed decreased sulfhydryl group content and increases in water holding capacity, whiteness value and hydrophobic interactions that increased gel strength value by up to 3.79 times that of untreated protein gel. Protein structural and Differential scanning calorimetry (DSC) analyses revealed that combined ultrasonic-TGase treatment increased both protein thermal denaturation temperature and UV absorbance (as compared to control and other treatment groups) that supported formation of MP gels with desirable characteristics. These results provide a theoretical basis for development of superior MP gels to promote greater utilization of this fish protein resource by the food industry.

Changes in collagen properties and cathepsin activity of beef M. semitendinosus by the application of ultrasound during post-mortem aging

The effects of ultrasound (0, 300 and 600 W for 20 min at the frequency of 20 kHz) followed by postmortem aging (0, 4 and 8 d aging time) on beef quality were evaluated. Ultrasound treatment, aging time and their interaction all significantly affected the pH and tenderness of beef (p < 0.05). Furthermore, ultrasound improved the cathepsin B + L activities and the solubility of collagen compared with the control without ultrasound treatment (p < 0.05). In terms of microstructure, the perimysium was ruptured by the ultrasound treatment which caused the collagen fibers to be disorderly and loosely arranged. In addition, ultrasound could affect the structural stability of collagen resulting in a significant reduction of thermal denaturation temperature (p < 0.05). The results showed that ultrasound could improve beef tenderness during postmortem aging by changing collagen structure and regulating the activities of cathepsin B + L.

Biochemical property and gel-forming ability of mackerel (Auxis thazard) surimi prepared by ultrasonic assisted washing

A low gel-forming ability is needed to be encountered using the dark-fleshed fish as a raw material. Optimal washing process can be a principled way of improving the gelling properties because washing is the most important step for surimi production. This study aimed to investigate the effect of ultrasonic-assisted washing (UAW) on the biochemical properties and gel-forming ability of frigate mackerel (Auxis thazard) surimi. Unwashed mince and conventional washing (CW) with 3-cycle of water (10 min per cycle) were compared to UAW for 5 and 10 min per cycle. UAW tended to improve the lipid removal, reduce the TCA-soluble peptide, and increase the surface hydrophobicity of surimi, but it had no influence on the Ca2+-ATPase activity, reactive sulfhydryl content, haem protein content, and lipid oxidation. UAW for 5 min per cycle rendered the surimi with the highest gel strength, whiteness, and water holding capacity as well as a regular aggregated network. With this method, the washing time can be reduced to 50% compared to the CW. Therefore, UAW for 5 min per cycle was an alternative approach for the production of mackerel surimi.

Post-mortem ultrasound and freezing of rabbit meat: Effects on the physicochemical quality and weight loss

High intensity ultrasound (HIU) is a technique with the potential to improve meat quality, however, more research is needed on its application within the chain of cold storage and freezing. This study evaluates the effect of HIU (40 kHz, 9.6 W/cm2, 20 and 40 min) and post-mortem development on the yield and physicochemical quality of rabbit meat in samples treated with HIU pre- and post-storage in a freezer (120 h at -20 °C). Twenty rabbit carcasses were vacuum packed 12 h post-mortem, placed in a fridge at 4 °C for 24 h, and divided in two groups (HIU application before or after freezing), before assigning the treatments. The results show that HIU before freezing produced intense and bright orange-yellow colours, whereas its application after freezing resulted in pale red tones. HIU application accelerates rigor mortis resolution when it is applied before freezing and causes a significant decrease in pH immediately following the HIU treatment. Post-freezing application of HIU is not recommended because it considerably increased weight loss and toughening of the meat when long exposure times were used (40 min). In contrast, a short treatment duration with HIU mitigated the effects of freezing and produced significant increases in water-holding capacity (WHC) after cold storage. The yield (weight loss) of the rabbit meat was not affected when HIU was applied pre-freezing. The application of HIU pre-freezing constitutes a promising technology because it increased the tenderness and the WHC of rabbit meat. However, more research is needed to improve the appearance before scaling up to industrial levels.

Influence of ultrasound-assisted tumbling on NaCl transport and the quality of pork

The present study aimed to investigate the impact of ultrasound-assisted tumbling (UAT; 20 kHz, 100, 300, 500 and 700 W) with different treatment time (30, 60, 90 and 120 min) on the diffusion and distribution of NaCl as well as the change of pork texture properties during curing. Results showed that in comparison with the single tumbling (ST), the NaCl content and the NaCl diffusion coefficient were increased along with UAT treatment (P < 0.05). The scanning electron microscopy and the energy dispersive X-ray analysis showed that UAT treatment changed the microstructure of pork which may facilitate the NaCl dispersion homogeneously. In addition, the moderate UAT treatment of 300 W with 60 min could significantly improve the tumbling yield, water-holding capacity and textural properties of pork compared with the ST treatment (P < 0.05). Meanwhile, in comparison with the ST group, protein extraction was considerably increased after UAT (300 and 500 W) treated for 120 min (P < 0.05). Our study demonstrated that UAT treatment could effectively promote the penetration and distribution of NaCl and improve pork meat quality via facilitating the extraction of meat protein.

Application of ultrasound treatment in chicken gizzards tenderization: Effects on muscle fiber and connective tissue

The tenderizing effect of different ultrasound treatments on the characteristics of muscle fibers and connective tissue of chicken gizzard was investigated. It could be concluded that the shear force and muscle fiber diameter of the sample treated with ultrasound for 500 W/30 min were decreased by 27.1% and 26.2%, respectively, while the myofibril fragmentation index (MFI) was increased by 238.1% than the control. More importantly, the contents of hydroxylysine pyridinoline and lysine pyridinoline of the samples treated with ultrasound for 500 W/30 min were 23.1% and 40.5% lower than those of the control. Tenderizing effect of 500 W/30 min sample on thermal stability was verified from the decrease in transition temperature (Tmax) (10.7%) and enthalpy (ΔH) (21.7%) of collage compared with the control. In general, proper ultrasound treatment could effectively improve the tenderness of gizzard, and 500 W/30 min had the best tenderization effect. Therefore, the treatment of ultrasound was considered as a promising and efficient technique in meat processing, especially for the meat tenderization.