Ultrasound: A new approach to reduce phosphate content of meat emulsions

A Comprehensive Review of Cured Meat Products in the Irish Market: Opportunities for Reformulation and Processing

Cured meat products constitute one of the meat categories commonly consumed in Ireland and has been part of the Irish cuisine and diet for many years. Ham, gammon, and bacon are some of the products that involve curing as part of the traditional processing methods. Common among these products are high levels of salt and the addition of nitrites. These products undergo processing treatments to create variety, preserve shelf-life, and develop their unique quality and safety characteristics. However, consumers are becoming more conscious of the level of processing involved in these products, and the effects of some components and ingredients might be perceived as unhealthy. Meat product developers have been exploring ways to reduce the amount of ingredients such as salt, saturated fat, and chemical preservatives (e.g., nitrites), which are linked to health concerns. This is a challenging task as these ingredients play an important techno-functional role in the products' quality, safety, and identity. While innovative processing techniques are being introduced and progress has been made in reformulation and packaging technologies, much is still unknown, especially regarding the applicability of many of the proposed interventions to a wide range of meat products and their sustainability at the industrial scale.

Effects of ultrasound-assisted intermittent tumbling on the quality of cooked ham through modifying muscle structure and protein extraction

BACKGROUND

Tumbling treatment is widely used in the production of cooked ham. However, traditional intermittent tumbling (IT) treatment is time-consuming. To enhance the tumbling efficiency, high-intensity ultrasound was used to assist IT treatment (UIT).

RESULTS

UIT treatment reduced the tumbling time and significantly improved the water holding capacity, tenderness, sliceability and texture of cooked ham compared to IT treatment. Furthermore, more violent destruction of meat tissue was exhibited in the UIT treatment. This change facilitated extraction of more salt-soluble protein, which in turn welded meat pieces tightly and improved the quality of the cooked ham.

CONCLUSION

UIT treatment could accelerate the tumbling process and enhance the quality of cooked ham. These results may provide guidance on effective strategies for a high-quality meat production process. © 2023 Society of Chemical Industry.

Effects of ultrasound-assisted curing on the quality and microstructure of low-sodium beef jerky

The effects of ultrasonic brine on the physicochemical properties, sensory quality and microstructure of low-sodium beef jerkies were investigated. Compared with control jerky brined in 1.5% NaCl solution, both of the direct reduction and partial replacement of 50% NaCl by KCl decreased the sodium content. Ultrasonic treatment resulted in sharp reduction in shear force. KCl substitution together with ultrasonic treatment caused the highest yield, a* value and water content, and the water activity of all groups were below 0.85. Only the direct reduction of NaCl had negative effects on the sensory quality. KCl substitution combined with ultrasonic treatment was the most suitable for producing low-sodium beef jerkies with high quality, possibly because the mixed salt had equal total salt content to control. Meanwhile, the cavitation and mechanical effects of ultrasound may unfold protein structure, increase myofibrillar fragmentation index and break the muscle fiber, thus improving the quality of beef jerky.

Effects of Shear Stress Waves on Meat Tenderness: Ultrasonoporation

Meat is an important part of the food pyramid in Mexico, to such an extent that it is included in the basic food basket. In recent years, there has been great interest in the application of so-called emerging technologies, such as high-intensity ultrasound (HIU), to modify the characteristics of meat and meat products. The advantages of the HIU in meat such as pH, increased water-holding capacity, and antimicrobial activity are well documented and conclusive. However, in terms of meat tenderization, the results are confusing and contradictory, mainly when they focus on three HIU parameters: acoustic intensity, frequency, and application time. This study explores via a texturometer the effect of HIU-generated acoustic cavitation and ultrasonoporation in beef (m. Longissimus dorsi). Loin-steak was ultrasonicated with the following parameters: time t_HIU = 30 min/each side; frequency f_HIU = 37 kHz; acoustic intensity I_HIU = ~6, 7, 16, 28, and 90 W/cm². The results showed that acoustic cavitation has a chaotic effect on the loin-steak surface and thickness of the rib-eye due to Bjerknes force, generating shear stress waves, and acoustic radiation transmittance via the internal structure of the meat and the modification of the myofibrils, in addition to the collateral effect in which the collagen and pH generated ultrasonoporation. This means that HIU can be beneficial for the tenderization of meat.

Do ultrasound form spontaneously nitrous pigments in nitrite-free pork meat batter?

The effects of ultrasound (US) on myoglobin modification, nitrous pigment formation, color, and total and free sulfhydryl content in nitrite-free pork meat batter were assessed. Five treatments were elaborated: Control (without US); TUS10'12 and TUS20'12 (sonication at 25 kHz, at 12 °C for 10 and 20 min, respectively); TUS10'18 and TUS20'18 (sonication at 25 kHz, at 18 °C for 10 and 20 min, respectively). Sonication for 20 min at 12 °C increased OxyMb and DeoxyMb pigments while reducing MetMb levels. This US condition also yielded higher red color indices and lower yellow color indices. Moreover, TUS20'12 exhibited enhanced nitrous pigment formation and decreased FerrylMb and free sulfhydryl (SH) values, indicating reduced oxidation in OxyMb and DeoxyMb pigments. In conclusion, the findings demonstrate that US can impart a cured color to nitrite-free meat products.

Ultrasound-assisted phosphorylation of goose myofibrillar proteins: improving protein structure and functional properties

BACKGROUND

Goose meat is rough and embedded with dense connective tissue, impairing protein solubility. Therefore, to improve the functional properties of goose myofibrillar protein (GMP), ultrasound was used to assist the phosphorylation of GMP.

RESULTS

The fact that GMP attached covalently with the phosphate group of sodium tripolyphosphate (GMP-STP) was disclosed directly by Fourier transform infrared spectroscopy. Furthermore, ultrasound significantly improved the hydrophobicity and solubility of GMP-STP, which could be attributed to the conversion of α-helix to β-sheet, β-turns, and random coils by sonication. The spatial stabilization of the protein phosphorylation process was boosted by ultrasound, making the droplets more dispersed, and thus an improvement in the functional properties of GMP-STP was observed. Water-holding capacity, oil-binding capacity, and emulsifying and foaming properties were best at an ultrasound power of 400 W.

CONCLUSION

Ultrasound-assisted phosphorylation has great potential to modulate the structure-function relationship of proteins. © 2023 Society of Chemical Industry.

Phosphate alternatives for meat processing and challenges for the industry: A critical review

Meat and meat products provide high levels of nutrition and many health benefits to consumers, yet a controversy exists regarding the use of non-meat additives, such as the inorganic phosphates that are commonly used in meat processing, and particularly their relationship to cardiovascular health and kidney complications. Inorganic phosphates are salts of phosphoric acid (e.g., sodium phosphate, potassium phosphate, or calcium phosphate), whereas organic phosphates are ester compounds (e.g., the phospholipids found in cell membranes). In this sense, the meat industry remains active in its efforts to improve formulations for processed meat products with the use of natural ingredients. Despite efforts to improve formulations, many processed meat products still contain inorganic phosphates, which are used for their technological contributions to meat chemistry including improvements in water-holding capacity and protein solubilization. This review provides a thorough evaluation of phosphate substitutes in meat formulations and other processing technologies that can help eliminate phosphates from the formulations of processed meat products. In general, several ingredients have been evaluated as replacements for inorganic phosphates with varying degrees of success such as plant-based ingredients (e.g., starches, fibers, or seeds), fungi ingredients (e.g., mushrooms and mushroom extracts), algae ingredients, animal-based ingredients (e.g., meat/seafood, dairy, or egg materials), and inorganic compounds (i.e., minerals). Although these ingredients have shown some favorable effects in certain meat products, none have exactly matched the many functions of inorganic phosphates, so the support of extrinsic technologies, such as tumbling, ultrasound, high-pressure processing (HPP), and pulsed electric field (PEF), may be necessary to achieve similar physiochemical properties as conventional products. The meat industry should continue to investigate ways to scientifically innovate the formulations of, and the technologies used in, processed meat products while also listening to (and acting upon) the feedback from consumers.

Development and Innovation in Cooked Ham Produced in Spain

The production of cooked ham has been gaining popularity in recent years in Spain. In general, the production process carried out by the companies remains traditional, and different production methods are therefore being sought to innovate and improve the quality of the product. This is either through pig crossbreeding, varying additives and ingredients, improving some stages of the production process, or providing nutritional and health claims that are useful to guiding the purchasing decision of consumers. Obviously, this series of changes must be subject to Spanish and European regulations in order to be marketed inside and outside the country.

Evaluation of chickpea protein isolate as a partial replacement for phosphate in pork meat batters: Techno-functional properties and molecular characteristic modifications

The effects of chickpea protein isolate (CPI, 0.5-2 %, w/w) on the techno-functional properties of 50 % reduced-phosphate pork meat batters (RPMBs) were explored. The results showed that 1.5-2 % CPI significantly decreased the cooking loss but significantly increased the emulsion stability, hardness, gumminess, chewiness and yellowness (b*) of RPMBs (P < 0.05). CPI altered molecular characteristics of RPMBs, as demonstrated by the increased storage modulus (G'), the conversion of free water into immobilized water, the reduced intensities of the aliphatic residue Raman bands, the decreased α-helical structure and the formation of well-organized gel networks with evenly distributed small fat globules. Principal component analysis and Pearson's correlation analysis indicated that CPI-induced changes in RPMB techno-functional properties were closely related to molecular characteristics. Hierarchical cluster analysis suggested that RPMBs supplemented with 1.5-2 % CPI were highly similar in techno-functional properties to the high-phosphate group. Therefore, CPI may potentially be used to develop reduced-phosphate meat products.

The Effect of Gelatin Coating and Sonication on the Quality Properties of Wet-Aging Pork Loins

In this study, we evaluate the effect of gelatin coating and sonication of wet-aged pork loin on quality. The moisture content of wet-aged pork loin with sonication and gelatin coating was the highest in the G5S sample (5% gelatin coating and sonication), while the moisture content of wet-aged pork loin with sonication was higher than that without sonication. The pH of wet-aged pork loin with sonication was lower than that without sonication. The aging loss of 5% gelatin coating with sonication was significantly lower than that of G0 (control), while the cooking loss was the lowest in G0 wet-aged pork loin. The water holding capacity of the wet-aged pork loin was the highest in G1. The thiobarbituric acid reactive substances value of wet-aged pork loin was significantly decreased with coating and not affected by sonication. The gelatin coating and sonication treatment significantly increased the myofibrillar fragmentation index of the samples. Shear force of wet-aged pork loin significantly decreased as the samples were gelatin-coated and sonicated. The myofibrillar and total protein solubilities were not significantly different between samples. In conclusion, the 1% gelatin coating with sonication can enhance the quality of wet-aged pork loin.

The preservable effects of ultrasound-assisted alginate oligosaccharide soaking on cooked crayfish subjected to Freeze-Thaw cycles

To improve the quality of cooked and frozen crayfish after repeated freeze-thaw cycles, the effects of alginate oligosaccharide (1 %, w/v) with ultrasound-assisted (40 W, 3 min) soaking (AUS) on the physicochemical properties were investigated. The AUS samples improved water-holding capacity with 19.47 % higher than the untreated samples. Low-field nuclear magnetic resonance confirmed that mobile water (T₂₂) in the samples after 5 times of freeze-thaw cycles was reduced by 13.02 % and 29.34 % with AUS and without treatment, correspondingly; and with AUS and without treatment, average size of the ice crystals was around 90.26 μm² and 113.73 μm², and average diameter of the ice crystals was 5.83 μm and 8.14 μm, respectively; furthermore, it enhanced the solubility and zeta potential, lowered the surface hydrophobicity, reduced the particle size, and maintained the secondary and tertiary structures of myofibrillar protein (MP) after repeated freeze-thawing. Gel electrophoresis revealed that the AUS treatment mitigated the denaturation of MPs. Scanning electron microscopy revealed that the AUS treatment preserved the structure of the tissue. These findings demonstrated that the AUS treatment could enhance the water retention and physicochemical properties of protein within aquatic meat products during temperature fluctuations..

Mechanism of improving emulsion stability of emulsion-type sausage with oyster mushroom (Pleurotus ostreatus) powder as a phosphate replacement

This research evaluated the potentiality of oyster mushroom powder (OMP) as a phosphate alternative by improving emulsion stability of emulsion-type sausage. Sausage without phosphate (NC), with 0.2% sodium triphosphate (PC), and with 1 and 2% OMP (M1 and M2) were prepared. The OMP addition improved the physicochemical properties of sausage, effectively prevented lipid oxidation, and delayed the growth of aerobic bacteria during 28 days of cold storage compared to NC. The M1 and M2 improved the emulsion stability similar to PC. M2 had the highest water holding capacity and apparent viscosity and the lowest cooking loss (P < 0.05). The addition of OMP resulted in different textural characteristics from that of phosphate due to the formation of emulsion structures randomly entrapped by filament-like components, which were derived from polysaccharides or the conjugates between polysaccharides and proteins. According to the results of this study, emulsion stability promoted by OMP was mainly due to the polysaccharides, which are involved in enhancing viscosity and steric hindrance.

Effect of high-pressure processing in improving the quality of phosphate-reduced Irish breakfast sausages formulated with ultrasound-treated phosphate alternatives

This work examined the effects of High-pressure processing (HPP) treatment on pork meat subsequently used to generate three phosphate-reduced sausage formulations (1-3) containing ultrasound (US) treated apple pomace (AP) and coffee silverskin (CSS) ingredients as phosphate replacers and compared against control (traditional) sausage formulations. Results showed that HPP and formulations produced significant interactive (P < 0.05) positive changes in the water holding capacity (WHC), cook loss, emulsion stability values. Texture, colour, TBARS, and emulsion stability values for sausage formulations showed no significant interactive impacts. Overall comparison of treatment sausage formulations against control formulations with non-HPP treated meat showed that HPP improved overall sausage quality attributes, where sausage formulation 2 employing HPP-treated meat and US-treated AP and CSS was regarded as the optimal sausage formulation. In conclusion, there is potential to manufacture sausages with reduced-phosphate concentration using combined novel processing technologies and clean label ingredients such as AP and CSS.

Understanding the Performance of Plant Protein Concentrates as Partial Meat Substitutes in Hybrid Meat Emulsions

Hybrid meat products are an excellent strategy to incorporate plant proteins into traditional meat formulations considering recent market trends focusing on the partial reduction in red meat content. In this work, we evaluated the effects of different concentrated plant proteins (soy, pea, fava bean, rice, and sunflower) in partially replacing meat in meat emulsion model systems. Soy, pea, and sunflower proteins showed great compatibility with the meat matrix, giving excellent emulsion stability and a cohesive protein network with good fat distribution. Otherwise, adding rice and fava bean proteins resulted in poor emulsion stability. Color parameters were affected by the intrinsic color of plant proteins and due to the reduction in myoglobin content. Both viscoelastic moduli, G′ and G″ decreased with the incorporation of plant proteins, especially for rice and fava bean. The temperature sweep showed that myosin denaturation was the dominant effect on the G′ increase. The water mobility was affected by plant proteins and the proportion between immobilized and intermyofibrillar water was quite different among treatments, especially those with fava bean and rice proteins. In vitro protein digestibility was lower for hybrid meat emulsion elaborated with rice protein. It is concluded that soy, pea, and mainly sunflower proteins have suitable compatibility with the meat matrix in emulsified products.

Consumer intention towards the phosphate-reduced processed meat products using the extended theory of planned behaviour

Phosphates are essential for maintaining various quality attributes of processed meat products such as water-binding properties, texture and sensory properties and their removal would drastically change the products' technical and sensory qualities. Currently, meat industries are faced with the challenge of removing phosphates to address the consumers' demand to remove the negatively perceived synthetic additives from processed meat products. This study measured these consumers' purchase intention of phosphate-reduced processed meat products with different quality, using the extended theory of planned behaviour (TPB). An online survey was conducted among the consumers (n = 548) of the Republic of Ireland (ROI) to predict their knowledge and attitude towards phosphate additives. Analysis of the survey responses showed that about two-third of the participants consumed processed meat products 5-6 times per week. The results of multiple linear regression showed that the theory constructs attitude, subjective norms, perceived health risks significantly (P < 0.05) influenced the consumer behavioural intention whereas the perceived behavioural control (PBC) produced insignificant impacts. The results also revealed that the extended TPB model predicted the consumers' intention with better explanatory power (adjusted R² = 0.46) than the original TPB model. In conclusion, various recommendations and implications were developed based on the results to improve the consumers' purchase intention of these products.

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.

Micronized cold-pressed hemp seed cake could potentially replace 50% of the phosphates in frankfurters

Present study aimed to investigate the concentration effect of micronized cold-pressed hemp seed cake (MCPHSC) on the quality profiles and sensorial attributes of 50% phosphates reduced frankfurters. The results showed that MCPHSC could be used as an ideal phosphates replacer for obviously decreasing the cooking loss and promoting textural and gel properties of reduced-phosphates frankfurters (P < 0.05), which was verified by scanning electron microscopy. Moreover, the incorporation of MCPHSC could significantly inhibit the occurrence of lipid oxidation of reduced-phosphates frankfurters during storage in a dose-dependent manner (P < 0.05). Additionally, replacing 50% phosphates with 2% (w/w) MCPHSC was found to possess the best optimal replacement effect to enhance the quality profiles of reduced-phosphates frankfurters (P < 0.05). However, a higher amount of MCPHSC had a negative effect on the sensorial evaluations of the reduced-phosphates frankfurters. Our results suggested that the addition of MCPHSC could be applied as a practical way for improving the quality defects of reduced-phosphates frankfurters.

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.

An overview of factors affecting the quality of beef meatballs: Processing and preservation

Beef meatball (BM) is a traditional delicious snack with rich nutrition and unique flavor, making it a preferred choice for most consumers. However, the quality of BM is easily affected by many factors, such as the processing, storage, and preservation, which limit the competitive positioning with respect to its market. Therefore, it is essential to pay attention to each step during the processing of BMs. Based on previous studies, this systematic review focuses on the effect of key processing factors (including raw materials and ingredients, beating, cooking methods, storage, and preservation) on the quality of BMs. Additionally, this study assessed the effect of each process factor on the physicochemical, sensory, nutritional, and safety attributes of BMs. Finally, the existing review will be beneficial in examining/describing the factors impacting the quality of BMs during processing, which would provide theoretical reference and scientific basis for the standardization and industrialization of BMs.

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 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.

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.

Reduction of phosphate content in frankfurters by up to 50% using micronized cold-pressed sesame seed cake

Our study assessed the effects of micronized cold-pressed sesame seed cake (MCPSSC) incorporation as a potential phosphate replacement on the textural and gel properties of 50% reduced-phosphate frankfurters. Our results indicated that moderate MCPSSC addition (4%) resulted in the strongest inhibition of textural quality deficits in reduced-phosphates frankfurters, which was confirmed via scanning electron microscopy. Moreover, although some differences were perceived in the sensorial parameters and flavour profile of reduced-phosphate frankfurters prepared with MCPSSC, all of them were deemed acceptable. Therefore, incorporating moderate amounts of MCPSSC is a feasible strategy to reduce the phosphate contents of frankfurters and promote "clean label" practices.

Clean Label Alternatives in Meat Products

Food authorities have not yet provided a definition for the term "clean label". However, food producers and consumers frequently use this terminology for food products with few and recognisable ingredients. The meat industry faces important challenges in the development of clean-label meat products, as these contain an important number of functional additives. Nitrites are an essential additive that acts as an antimicrobial and antioxidant in several meat products, making it difficult to find a clean-label alternative with all functionalities. Another important additive not complying with the clean-label requirements are phosphates. Phosphates are essential for the correct development of texture and sensory properties in several meat products. In this review, we address the potential clean-label alternatives to the most common additives in meat products, including antimicrobials, antioxidants, texturisers and colours. Some novel technologies applied for the development of clean label meat products are also covered.

Combined effect of ultrasound and basic electrolyzed water on the microbiological and oxidative profile of low-sodium mortadellas

Ultrasound (US) and basic electrolyzed water (BEW) are considered emerging technologies; however, few studies have addressed the combination of both technologies in emulsified meat products. This study aimed to evaluate the individual and combined effect of US (25 kHz; 175 W; 20 min) and BEW (pH 10.99; -92.33 mV) on the microbiological and oxidative profile of low-sodium mortadellas (30% of NaCl reduction) stored for 90 days at 5 °C. The use of BEW alone increased the pH and reduced the redox potential of mortadellas, while the US did not affect these parameters. The combined application of US and BEW reduced the lactic acid bacteria counts by up to 0.36 log CFU/g. In addition, BEW stimulated the growth of lipolytic bacteria. The treatments subjected to US application alone showed a lower growth rate of lipolytic bacteria, lower lipid and protein oxidation, and higher ΔE* values. Therefore, the application of US and BEW may be a promising strategy to improve the microbiological and oxidative quality of mortadella during storage.

Influence of high power ultrasound on natural microflora, pathogen and lactic acid bacteria in a raw meat emulsion

Raw meat emulsions may have natural, spoilage and pathogenic microorganisms due to the origin and characteristics of this food matrix. All of these microorganisms must be minimized during industrial processing to make food consumption safe and meet quality regulations. Therefore, in this research, the effect of probe ultrasound on the inactivation of three kinds of microorganisms in a raw meat emulsion is evaluated. The microorganisms are: natural microflora NAM, Listeria monocytogenes LIS, and Lactobacillus delbrueckii LAC. A high-intensity probe ultrasound system was used, during 1.0, 2.5, 5.0, 7.5 and 10 min, with pulsed waves of 0.0, 10, 20 and 30 seg, and 200, 250, 300, 350 and 400 W of power. The interrelation between time, wave pulse cycle, and power factors was assessed. The results showed a positive linear independence effect in the treatments without wave pulse for each microorganism, and a quadratic interaction with the time and the ultrasound power for the inactivation of the three kinds of microorganisms. Besides, the desirability function for the inactivation reached up to 60% of the microbial population with the probe ultrasound treatment, with 10 min, a 7.56 s wave pulse and 400 W of power. Thus, these results could be useful to decide the incorporation of mild and emerging technologies in a meat industry line process.

Effects of ultrasonic-assisted cooking on the volatile compounds, oxidative stability, and sensory quality of mortadella

Ultrasound is a form of green technology that has been applied efficiently to improve processes in the food industry. This study evaluated the application of ultrasound to reduce the cooking time of mortadella. The volatile compounds, oxidative stability, and sensory quality of mortadella were evaluated. Four cooking conditions were used, as follows: Control, corresponding to the cooking time traditionally used in the meat industry; TUS100 and TUS50: cooking with US (25 kHz) and 50% reduction of the cooking time of Control, using 100% (462 W) and 50% (301 W) amplitude, respectively; and TWUS: cooking without the application of US and 50% reduction of the cooking time of Control. TUS100 and TUS50 showed an increase of 10.8% and 29.4%, respectively, in the total amount of terpenes on the first day of storage in relation to the Control. The presence of nonane on the 60th day only in the US-treated samples (0.22 × 10⁶ vs 0.11 × 10⁶ for TUS100 and TUS50, respectively) indicated that the US treatment may have induced higher oxidation in mortadella. The oxidative stability index ranged from 274 to 369 days for TUS100 and the Control, respectively. The treatments TWUS and TUS50 showed a lower sensory quality at the end of storage. On the other hand, TUS100 presented sensory quality similar to the Control, demonstrating that ultrasonic-assisted cooking using a 100% amplitude is an alternative to reduce the cooking time without affecting the product quality.

Application of temperature-controlled ultrasound treatment and its potential to reduce phosphate content in frankfurter-type sausages by 50

The objective of this study was to evaluate the effect of ultrasound treatments with different durations (15, 20, 25, 30, and 35 min) at a low static temperature (12 °C) controlled by an intelligent temperature control and monitoring system on the quality of 50% reduced-phosphate frankfurters. The results show that without ultrasound treatment, phosphate reduction caused some obvious deficits in the textural properties, sensorial parameters, and oxidative stability of frankfurters. Moreover, 25-min ultrasound treatment could significantly lower the cooking loss and enhance emulsion stability, textural properties, and sensorial parameters of reduced phosphate frankfurters, which was also verified by dynamic water distribution analysis and microstructural observation. Additionally, low constant temperature during ultrasound treatment was another crucial factor in retarding lipid oxidation during storage. Therefore, ultrasound treatment with moderate duration and stable low temperature could be considered a successful approach to obtain healthier reduced-phosphate frankfurters under the "clean label" concept.

Strategies to Improve Meat Products' Quality

Meat products represent an important component of the human diet, their consumption registering a global increase over the last few years. These foodstuffs constitute a good source of energy and some nutrients, such as essential amino acids, high biological value proteins, minerals like iron, zinc, selenium, manganese and B-complex vitamins, especially vitamin B12. On the other hand, nutritionists have associated high consumption of processed meat with an increased risk of several diseases. Researchers and processed meat producers are involved in finding methods to eliminate nutritional deficiencies and potentially toxic compounds, to obtain healthier products and at the same time with no affecting the sensorial quality and safety of the meat products. The present review aims to summarize the newest trends regarding the most important methods that can be applied to obtain high-quality products. Nutritional enrichment with natural bioactive plant compounds (antioxidants, dietary fibers) or probiotics, reduction of harmful components (salt, nitrate/nitrite, N-nitrosamines) and the use of alternative technologies (high-pressure processing, cold plasma, ultrasounds) are the most used current strategies to accomplish this aim.

Effect of ultrasound on proteolysis and the formation of volatile compounds in dry fermented sausages

Ultrasound (US) is an emerging technology capable of affecting enzymes and microorganisms, leading to the release of amino acids and the formation of volatile compounds. The effect of different exposure times (0, 3, 6, and 9 min) of US (25 kHz, 128 W) on the proteolysis and volatile compounds of dry fermented sausages during processing (day 0 and 28) and storage (day 1 and 120) was investigated. Lower alanine, glycine, valine, leucine, proline, methionine, and tyrosine levels were observed at the beginning of manufacture for the sample subjected to 9 min of US (p < 0.05) when compared to the control. During the storage period, the samples subjected to US exposure for 3 and 6 min exhibited higher free amino acid levels. A greater formation of hexanal, pentanal, and hexanol was observed in the US-treated samples when compared to the control (p < 0.05), as well as other derivatives from the oxidation reactions during the storage. The use of US (25 kHz and 128 W) in the manufacture of dry fermented sausages can affect the proteolysis and the formation of compounds derived from lipid oxidation during the storage.

Monitoring Thermal and Non-Thermal Treatments during Processing of Muscle Foods: A Comprehensive Review of Recent Technological Advances

Muscle food products play a vital role in human nutrition due to their sensory quality and high nutritional value. One well-known challenge of such products is the high perishability and limited shelf life unless suitable preservation or processing techniques are applied. Thermal processing is one of the well-established treatments that has been most commonly used in order to prepare food and ensure its safety. However, the application of inappropriate or severe thermal treatments may lead to undesirable changes in the sensory and nutritional quality of heat-processed products, and especially so for foods that are sensitive to thermal treatments, such as fish and meat and their products. In recent years, novel thermal treatments (e.g., ohmic heating, microwave) and non-thermal processing (e.g., high pressure, cold plasma) have emerged and proved to cause less damage to the quality of treated products than do conventional techniques. Several traditional assessment approaches have been extensively applied in order to evaluate and monitor changes in quality resulting from the use of thermal and non-thermal processing methods. Recent advances, nonetheless, have shown tremendous potential of various emerging analytical methods. Among these, spectroscopic techniques have received considerable attention due to many favorable features compared to conventional analysis methods. This review paper will provide an updated overview of both processing (thermal and non-thermal) and analytical techniques (traditional methods and spectroscopic ones). The opportunities and limitations will be discussed and possible directions for future research studies and applications will be suggested.