Comparative physicochemical characteristics and in vitro protein digestibility of alginate/calcium salt restructured pork steak hydrolyzed with bromelain and addition of various hydrocolloids (low acyl gellan, low methoxy pectin and κ-carrageenan)

Recent insights into bonding technologies in restructured meat production: A review

Restructuring meat products is one way of improving material utilization and economic efficiency. In this process of combining meat pieces or granules to form larger pieces of meat, the additives and processing techniques employed in bonding the restructured meat play crucial roles in the formation of the structure and appearance of the meat while simultaneously reducing nutrient and water loss and enhancing flavor. This study reviews the adhesives commonly used in meat recombination technology, including transglutaminase, glucono-delta-lactone, fibrin, gelatin, and gel emulsifiers such as hydrophilic colloid, phosphate, starch, and cellulose. Additionally, processing technologies such as high-pressure, ultrasonic, vacuum-assisted, microwave, and three-dimensional printing are discussed, with emphasis on their principles, properties, functionalities, and safety. The study further summarizes the application and research progress of various bonding techniques in restructured meat. It analyzes the advantages, challenges, and development prospects of these techniques to provide support for further research in this field.

Determination of carrageenan and konjac gum in livestock meat and meat products by ultra performance liquid chromatography-tandem mass spectrometry

At present, gum-injected meat appeared in the market, which has seriously damaged the legitimate rights and interests of consumers. Therefore, a method for the determination of carrageenan and konjac gum in livestock meat and meat products by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established. The samples were hydrolyzed by hydrogen nitrate. After centrifugation and dilution, the supernatants were detected by the UPLC-MS/MS and the concentration of target compounds in samples were calibrated by the matrix calibration curves. A good linear relationship was observed in the concentration range of 5-100 μg/mL with correlation coefficients of more than 0.995. The limits of detection (LODs) and limits of quantification (LOQs) were found to be 20 and 50 mg/kg, respectively. The recoveries at three spiked levels (50, 100 and 500 mg/kg) in blank matrix were in the range of 84.8-108.6% with the relative standard deviations between 1.5% and 6.4%. The method has the advantages of convenient, accurate and efficient, and can be used as an effective method for detecting carrageenan and konjac gum in the different kinds of livestock meat and meat products.

Effect of κ-carrageenan on the quality of crayfish surimi gels

The demand for crayfish surimi products has grown recently due to its high protein content. This study examined the effects of varying κ-carrageenan (CAR) and crayfish surimi (CSM) concentrations on the gelling properties of CAR-CSM composite gel and its intrinsic formation process. Our findings demonstrated that with the increasing concentration of carrageenan, the quality of CAR-CSM exhibited rising trend followed by subsequently fall. Based on the textural qualities, the highest quality CAR-CSM was achieved at 0.3% carrageenan addition. With the exception of chewiness, and the cooking loss of the gel system was 1.62%, whiteness was 82.35%, and the percentage of β-sheets increased to 57.18%. Further increase in CAR (0.4-0.5%) addition resulted in internal build-up of LCAR-CSM, conversion of intermolecular forces into disulfide bonds and gel breakage. This study exudes timely recommendations for extending the CAR application for the continuous development of crayfish surimi and its derivatives and its overall economic worth.

Evaluating the effect of thermo-reversible and thermo-irreversible curdlan gels on the gelling properties and in vitro digestibility of myofibrillar protein gels under low-salt condition

The purpose of the present study was to investigate the gelling properties and in vitro digestibility of myofibrillar protein (MP) gels under low-salt condition as mediated by different concentrations of thermo-reversible curdlan gels (TRC) or thermo-irreversible curdlan gels (TIRC). The results showed that the incorporation of TRC or TIRC obviously improved the gel strength and water holding capacity of MP gels (P < 0.05). Those properties were most improved by adding 0.3 % TRC or TIRC with gel strength of 0.18 N or 0.17 N and WHC of 54.85 % or 49.05 %. Meanwhile, both TRC and TIRC promoted the transformation of α-helix into β-sheet, as well as hydrophobic interactions and disulfide bonds, which are the main forces for the maintenance of the MP gels. The microstructure revealed that the formation of dense and uniform protein network structures can be promoted by the addition of TRC or TIRC. The different modes of interaction between TRC or TIRC and MP resulted in different microstructures of the MP gels. Furthermore, incorporation of TRC or TIRC significantly reduced in vitro protein digestibility, especially for the 0.3 % (w/w) form (P < 0.05). Meanwhile, MP gels had the lowest in vitro protein digestibility after the addition of TRC (66.67 %) compared to the form of TIRC (70.93 %). Therefore, our present study indicated that incorporation form of TRC or TIRC have distinct implications on regulating the gelling properties and in vitro digestibility of MP gels under low-salt condition.

Modern Concepts of Restructured Meat Production and Market Opportunities

Restructured meat (RM) products are gaining importance as an essential component of the meat industry due to consumers' interest in health benefits. RM products imply the binding or holding of meat, meat by-products, and vegetable proteins together to form a meat product with meat's sensory and textural properties. RM products provide consumers with diversified preferences like the intake of low salt, low fat, antioxidants, and high dietary fiber in meat products. From the point of environmental sustainability, RM may aid in combining underutilized products and low-valued meat by adequately utilizing them instead of dumping them as waste material. RM processing technique might also help develop diversified and new hybrid meat products. It is crucial to have more knowledge on the quality issues, selection of binding agents, their optimum proportion, and finally, the ideal processing techniques. It is observed in this study that the most crucial feature of RM could be its healthy products with reduced fat content, which aligns with the preferences of health-conscious consumers who seek low-fat, low-salt, high-fiber options with minimal synthetic additives. This review briefly overviews RM and the factors affecting the quality and shelf life. Moreover, it discusses the recent studies on binding agents in processing RM products. Nonetheless, the recent advancements in processing and market scenarios have been summarized to better understand future research needs. The purpose of this review was to bring light to the ways of sustainable and economical food production.

Encapsulation of probiotics in freeze-dried calcium alginate and κ-carrageenan beads using definitive screening design: A comprehensive characterisation and in vitro digestion study

This research aimed to evaluate the encapsulation of the probiotic strain, Streptococcus thermophilus, in hydrogels employing sodium alginate (SA) with κ-carrageenan (κC) in gelation baths with varying salt concentrations (CaCl2 and KCl) followed by freeze-drying. The experimentation was conducted at varying levels of κC (0-0.5 % w/v) and SA (2-4 %). Freeze-dried hydrogels were evaluated based on encapsulation efficiency and loss of viability and further characterised. The study could successfully establish an encapsulation efficiency of 87.814 % and a viability loss of 1.201 log CFU·g-1 for the optimised samples. The SEM micrographs of the optimised Ca-alginate/κC hydrogels exhibited a much denser network with fewer pores. The influence of SA/κC in the beads was confirmed by FTIR and DSC, where distinct peak shifts were observed, which indicated the presence of κC and SA polymers. The probiotic survival under simulated gastrointestinal tract (GIT) conditions, performed in accordance with the INFOGEST protocol, indicated that the optimised Ca-alginate/κC beads had a lower rate of release in the gastric phase and a much higher rate of survival and release in the intestinal phase than the control sample. The swelling behaviour of beads varied due to varying pH in both gastric and intestinal phases, and the κC in the optimised beads affected the swelling ratio significantly.

Mastering textural control in multi-polysaccharide gels: Effect of κ-carrageenan, konjac glucomannan, locust bean gum, low-acyl gellan gum, and sodium alginate

To comprehend the intricate interplay of five common food polysaccharides, κ-Carrageenan (KC), konjac glucomannan (KGM), locust bean gum (LBG), low-acyl gellan gum (LAG), and sodium alginate (SA), within composite polysaccharide gels, widely employed for textural modulation and flavor enhancement. This study systematically modulates the quantities of these five polysaccharides to yield six distinct multi-polysaccharide gels. The unique impact of each polysaccharide on the overall quality of composite gels were studied by thermostability, microstructure, water-holding capacity (WHC), texture, and sensory attributes. The findings unequivocally manifest the phenomenon of thermoreversible gelation in all composite gels, except for the KC-devoid sample, which displayed an inability to solidify. Notably, KGM, LBG, and LAG emerged as pivotal enhancers of the network structure in these composite gels, while SA was identified as a promotor of layered structure, resulting in a reduction of surface hardness. Leveraging principal component analysis (PCA) to analyzed 14 critical evaluation parameters of the five multi-polysaccharide gels, revealing the order as follows: KC > KGM > SA > LAG > LBG. These findings would imparts valuable insights into the pragmatic utilization of multi-polysaccharide gels for the development of food products (e.g. Bobo balls in milk tea) with tailored textural and sensory attributes.

Starch can act differently when combined with alginate or gellan gum to form hydrogels

Microgels were tailored by combining starches from different sources (corn, potato or phosphated) and anionic polysaccharides (gellan gum or alginate) using ionic gelation. Rheological analysis pointed out a lower consistency index for alginate-based solutions compared to the gellan-based ones and, therefore, this favored the formation of smaller droplets during the atomization process (58.74 ± 1.72 µm vs. 101.38 ± 2.71 µm). Additionally, it was noticed that the starch granule size isdirectly related to the diameter of the particle formed, both for gellan and alginate systems. The combination between starches and anionic gums still promoted an increase in the water holding capacity, probably due to the presence of additional hydrophilic groups from starch. According to the mechanical properties, starch acts differently when combined with alginate or gellan gum, considering it strengthened the biopolymeric network for the alginate-based gels increasing the stress at rupture values (except for potato starch), while it decreasedthe hardness and elasticity for gellan-based gels. Microparticles based on gellan and alginate showed high anthocyanin encapsulation efficiency (EE ≥ 80%) in all systems. In these cases, the addition of starch did not contribute to increasing this property, even though starch granules filled the gel pores. The high EE showed that the studied systems allow the encapsulation of anthocyanin and suggest possible encapsulation of other hydrophilic bioactive compounds, considering the best type of starch for each application.

The level of sulfate substitution of polysaccharide regulates thermal-induced egg white protein gel properties: The characterization of gel structure and intermolecular forces

Sulfated polysaccharides exhibit great potential for regulating protein-protein interactions. In the present study, three sulfated microcrystalline cellulose (MCS) with different degrees of sulfate substitution (DSS: 0.33, 0.51, 0.61) were synthesized and the effects of DSS on the regulation of egg white protein (EWP) aggregation and gelation properties were investigated. The results found that the improvement of protein mechanical properties by MCS is closely related to the level of sulfate substitution. The higher the DSS, the more ordered protein aggregates and compact gel network formed during heating as compared to that of pure EWP. Lower DSS (0.33) shows little effect on the mechanical properties of EWP. Furthermore, all the MCSs could significantly destroy the tertiary structure of protein molecules during heating, while for the secondary structure, MCS with higher DSS (0.51 and 0.61) could effectively control the decreasing tendency of α-helix and increasing tendency of β-sheet. Hydrophobic interactions were recognized as the major intermolecular force in the compact mixed gels (EWP/MCS2 and EWP/MCS3 gels, DSS was 0.51 and 0.61, respectively). These findings provide a vital understanding of the gelling mechanism of the protein-polysaccharide system and the application of sulfated polysaccharides in protein-based food products.

In-Depth Insight into the Mechanism of Incorporation of Abelmoschus manihot Gum on the Enhancement of Gel Properties and In Vitro Digestibility of Frankfurters

This study aimed to investigate the effects of different concentrations (0.1, 0.2, 0.3, 0.4, and 0.5% w/w) of Abelmoschus manihot gum (AMG) on the gel properties and in vitro digestibility of frankfurters. The results indicated that AMG incorporation significantly enhanced the emulsion stability and texture of frankfurters, as well as the dynamic rheological characteristics of raw meat batter, with the optimal concentration being 0.3% (p < 0.05). Furthermore, hydrogen bonds and disulphide bonds were the main molecular forces of the frankfurters in the presence of AMG. Microstructural images showed that more uniform and dense microstructures of frankfurters were formed due to AMG supplementation. In addition, AMG incorporation significantly increased the in vitro protein digestibility of frankfurters as the level of addition increased (p < 0.05). In conclusion, our results provided critical information for the practical application of AMG in the production of emulsified meat products.