Research Progress and Teaching Exploration of Physical Processing Technology for Reduced-Salt Gel Meat Products

Salt assumes a significant role in the production of meat gels. Excessive intake of salt adversely affects human health, and consumers' demand for reduced-salt meat products is escalating. This review primarily introduces the characteristics of the physical processing technology of reduced-salt gel meat products, such as the technology of ultrasonic, high-pressure processing, beating, plasma, and magnetic field, and its role in reduced-salt gel meat processing, and explores means to improve the teaching effect of the physical processing technology of reduced-salt gel meat products in the major of Food Science and Engineering. It was found that physical processing techniques, such as ultrasound, high-pressure processing, and beating, could enhance the solubility and processing performance of myofibrillar protein by improving the meat structure and protein conformation, increasing the interaction between proteins, water, and fat molecules, and enhancing the texture, water-holding capacity, and sensory quality of reduced-salt gel meat products. In the promotion and teaching of physical processing technology, it is necessary to strengthen interdisciplinary integration and scientific research activities according to the customs, laws and regulations of different countries and regions, combined with the development frontier of the technology, and develop reduced-salt gel meat products that meet local needs according to local conditions.

Effects of umami substances as taste enhancers on salt reduction in meat products: A review

Sodium is one of the essential additives in meat processing, but excessive sodium intake may increase risk of hypertension and cardiovascular disease. However, reducing salt content while preserving its preservative effect, organoleptic properties, and technological characteristics poses challenges. In this review, the mechanism of salt reduction of umami substances was introduced from the perspective of gustation-taste interaction, and the effects of the addition of traditional umami substances (amino acids, nucleotides, organic acids(OAs)) and natural umami ingredients (mushrooms, seaweeds, tomatoes, soybeans, tea, grains) on the sensory properties of the meat with reduced-salt contents were summarized. In addition, the impacts of taste enhancers on eating quality (color, sensory, textural characteristics, and water-holding capacity (WHC)), and processing quality (lipid oxidation, pH) of meat products (MP) and their related mechanisms were also discussed. Among them, natural umami ingredients exhibit distinct advantages over traditional umami substances in terms of enhancing quality and nutritional value. On the basis of salt reduction, natural umami ingredients improve the flavor, texture, WHC and antioxidant capacity. This comprehensive review may provide the food industry with a theoretical foundation for mitigating salt consumption through the utilization of umami substances and natural ingredients.

High-pressure processing influences the conformation, water distribution, and gel properties of pork myofibrillar proteins containing Artemisia sphaerocephala Krasch gum

•

Artemisia sphaerocephala Krasch gum could improve WHC and gel strength.

•

HPP (≤200 MPa) induced high immobilized water proportion and a dense, uniform microstructure of MP-AG gels.

•

HPP (>200 MPa) decreased surface hydrophobicity and storage modulus of MP-AG solutions.

•

HPP (>200 MPa) increased particle size and amount of reactive sulfhydryl group of MP-AG solutions.

•

The results have great potential for developing reduced-sodium meat products.

The effect of high-pressure processing (100–4 00 MPa) on conformation, water distribution, and gel characteristics of reduced-sodium (0.3 M NaCl) myofibrillar protein containing 0.15% Artemisia sphaerocephala Krasch gum (AG) was investigated. The addition of AG resulted in the increase of WHC, proportion of immobilized water, and gel strength. Then, the WHC, proportion of immobilized water, and gel strength peaked after 200 MPa treatment, attributed to increased solubilization and zeta potential of MP, decreased particle size of MP, exposure of intrinsic tryptophan residues and the partial transformation of α-helix into β-sheet in MP. Moreover, 300 and 400 MPa induced decreases in surface hydrophobicity, solubility and storage modulus, resulting in the formation of loose and disordered gel structures with attenuated WHC. These results suggest that application of moderate HPP (200 MPa) combined with AG could provide a novel approach to improve the WHC and gelation properties of reduced-sodium meat products.

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.

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.

A systematic review of clean-label alternatives to synthetic additives in raw and processed meat with a special emphasis on high-pressure processing (2018-2021)

The meat industry is continuously facing challenges with food safety, and quality losses caused by thermal processing. This systematic review reports recent clean label approaches in high-pressure production of meat. A literature search was performed using Scopus, Web of Science, PubMed, and Springer databases for studies published in 2018-2021. In this regard, 69 articles were assessed out of 386 explored research articles in the identified stage. The findings indicate that most of the earlier work on high-pressure processing (HPP) focused on physicochemical and sensorial meat quality rather than providing nutritional aspects and clean-label solutions. However, few advanced studies report effective and innovative solutions to develop low salt/fat, and reduced nitrite for raw and cured meat products. HPP could help on increasing the shell life by five times in meat products; however, it depends on the formulation and packaging, etc. HPP can also preserve nutrients by using this non-thermal technology and reduce food waste as once the shelf life of products is known, it easily reduces the shrinkage in the marketplace. This review explores the latest trend of experimental research in high-pressure processing alone, or multi-hurdle techniques employed to increase the effect of clean-label ingredients for enhanced meat safety/quality.

Effects of high-pressure processing on the functional properties of pork batters containing Artemisia sphaerocephala krasch gum

Here, the effect of high-pressure conditions (0.1-400 MPa) on the water-loss, texture, gel strength, color, dynamic rheological property, and water migration of pork batters containing 0.1% (W/W) Artemisia sphaerocephala krasch gum (PB-AG) is studied. Results indicated that the cooking yield, water-holding capacity, texture, gel strength, L^* values, and G' values increased with the increase in pressure (0.1-300 MPa) (p < 0.05). Dynamic rheological results (G') revealed that the thermal gelling ability of the PB-AG gel gradually increased with pressure (0.1-300 MPa). The minimum of T₂₂ content was observed and the proportion of immobilized water decreased at 300 MPa by low-filed nuclear magnetic resonance. However, excessive high-pressure processing treatments (400 MPa) resulted in lower gel strength, WHC, texture, and G'. The scanning electron microscopy results shown that a denser network structure with small cavities was observed at 300 MPa. Therefore, moderate pressure treatment (≤300 MPa) may improve gelation properties of PB-AG gel, while excessive pressure treatment (400 MPa) may weaken the gelation properties. PRACTICAL APPLICATION: High-pressure processing combining Artemisia sphaerocephala krasch gum could enhance the gelation properties of pork batters. To do so, establishing knowledge on gelation properties of pork batters with Artemisia sphaerocephala krasch gum at different pressure levels treatment would be of paramount importance, because this contributes furnishing engineering data pertinent to the technical progress for the processing of emulsion-type meat with high quality.

Effect of high intensity ultrasound on the gelation properties of wooden breast meat with different NaCl contents

The current study was conducted to investigate the effect of different high intensity ultrasound (HIU) amplitudes on the gelation properties of wooden breast (WB) meat batter prepared with 1% and 2% NaCl. Results indicated that HIU effectively enhanced the water holding capacity (WHC) of WB at 1% and 2% NaCl, and enabled WB to obtain better WHC than the normal. The thermal stability of WB was affected by HIU, and the difference of G'_end between WB and normal was reduced at 2% NaCl. HIU continuously decreased the particle size of WB at 1% NaCl, whereas opposite trends were observed at 2% NaCl. In addition, HIU transformed α-helix structure of WB to random coil at 1% NaCl, whereas to β-sheet structure at 2% NaCl. Overall, HIU can be utilized to improve the gelation properties of WB meat with the potential to produce low- and common-salt gel-type meat products.

Compensation of high-pressure processing for the solubility of sodium-reduced chicken breast myosin with three anion types of potassium salts

The effect of high-pressure processing (200 MPa, 10 min) on the solubility of chicken breast myosin with 25% molar substitution of Na+ by 3 anion types of potassium salts (KCl, K-lactate, and K-citrate) was investigated. The results showed that the lower hydrophobic group and reactive sulfhydryl group of nonpressurized myosin with the replacement of organic K-lactate or K-citrate possibly contributed to the aggregation of myosin molecules compared with the KCl group and thus decreased the solubility of both. In the presence of lactate or citrate, the high-pressure processing caused an increase in the surface hydrophobicity and reactive sulfhydryl group, indicating the unfolding of myosin molecule. Meanwhile, the increased hydration state and the decreased apparent viscosity suggested the disruption of protein-protein interactions and the strengthening of myosin-water interactions in pressurized myosin, ultimately resulting in increased solubility of the pressurized myosin with both organic potassium salts. The compensation of high-pressure processing is interesting for the efficient selection of the anion type in developing sodium-reduced industrial meat products.