Effect of microbial transglutaminase and sodium caseinate on quality of chicken döner kebab

The effect of microbial transglutaminase (MTGase) and sodium caseinate on the quality of chicken d?ner kebab was investigated. Yield, color, pH, SDS-polyacrylamide gel electrophoresis (SDS-PAGE), texture, and sensory evaluations were measured. The results of SDS-PAGE showed that addition of MTGase with or without sodium caseinate created cross-linking between meat proteins. Texture measurements indicated that the effect of the enzyme on binding properties of chicken meat is more effective if it is used with sodium caseinate (P<0.05). Sensory evaluation was not significantly different statistically among treatments.     

Study of two different cold restructuring processes using two different qualities of hake (Merluccius capensis) muscle,with addition of microbial transglutaminase

BACKGROUND: Microbial transglutaminase (MTGase) can improve the mechanical and functional properties of restructured fish products without the need of thermal gelation. The present study seeks to determine whether, for different setting times, MTGase activity in restructured hake muscle made with pieces or with homogenised muscle can be affected by the quality of the protein in the raw materials. RESULTS: As regards mechanical properties, samples of both qualities subjected to the two different processes attained a suitable consistency after setting for 24 h at 5 °C. The quality of the protein in the sample is important when pieces are used for restructuring, but not when sample is homogenised. Also, there were strong correlations between residual MTGase activity up to 12 h and mechanical properties and electrophoretic band density. Water binding capacity (WBC) was not significantly altered by MTGase addition. CONCLUSION: The experimental combination of 10 g kg^?1 of MTGase, 15 g kg^?1 of sodium chloride and 7.5 g kg^?1 of sodium caseinate was suitable for the production of minimally processed raw restructured fish products made with two different qualities of fish protein and two different restructuring processes. In the restructured products made with pieces, the protein quality significantly affected final properties, but in finely homogenised product the protein quality was less important. Copyright © 2009 Society of Chemical Industry     

Use of microbial transglutaminase and nonmeat proteins to improve functional properties of low NaCl, phosphate-free patties made from channel catfish (Ictalurus punctatus) belly flap meat

ABSTRACT:  This study was aimed at developing value-added low sodium chloride (NaCl), phosphate-free restructured patties using minced channel catfish ( Ictalurus punctatus ) belly flap meat. The effect of microbial transglutaminase (MTGase) and nonmeat proteins (isolated soy protein, ISP, and whey protein concentrate, WPC; 1.7%, respectively) alone and in combination were evaluated to improve cooking yield and textural properties in patties with reduced NaCl and no phosphate. The concentration effect of MTGase (0.05% to 0.7%) was also studied. The addition of MTGase increased textural properties such as binding strength, hardness, cohesiveness, chewiness, and springiness, but decreased cooking yield of the patties ( P < 0.05). Isolated soy protein increased cooking yield ( P < 0.05), but did not affect textural properties. Inclusion of WPC did not increase cooking yield or impact textural properties of patties. The combination of MTGase and ISP significantly increased both the cooking yield and textural properties of patties. As the concentration of MTGase increased at constant ISP, the textural properties of cooked patties significantly increased, but cooking yield decreased ( P < 0.05). In conclusion, we suggest that the combination of 0.05% to 0.1% of MTGase with 1.7% ISP is optimal for development of a low NaCl, phosphate-free patty using minced catfish belly flap meat.     

Use of dairy proteins and microbial transglutaminase to obtain low-salt fish products from filleting waste from silver carp (Hypophthalmichthys molitrix)

Restructured fish products from the filleting waste from silver carp (Hypophthalmichthys molitrix) were obtained using sodium caseinate (1%), whey protein concentrate (WPC) (1%) or MTGase (0.3%) at different levels of salt (0%, 1% or 2%). The restructured products were obtained by incubating at 40 °C for 60 min and then at 90 °C for 20 min. Changes in the mechanical properties were studied by measuring changes in the textural profile analyses, punch test and torsional test analyses and expressible water. The mechanical properties increased when the salt level was also increased. The mechanical properties of non-salted and low-salt products were increased by using dairy proteins. Sodium caseinate had a greater effect in improving mechanical properties than WPC. MTGase increased expressible water. The results obtained showed that the mechanical properties of low-salt restructured fish products can be improved by using dairy proteins combined with MTGase, with a slight increase in expressible water.     

Use of Soy Protein and Microbial Transglutaminase as a Binder in Low-sodium Restructured Meats

ABSTRACT: Pork sticks were prepared by mixing pork chucks with various amounts of bisulfite-treated soy protein and microbial transglutaminase (MTGase) to evaluate the potential of using soy protein as meat binders. According to tensile strength, the favorable conditions for binding the restructured pork chunks were 5% soy protein containing 0.2% NaHSO₃ and 20 unit MTGase/g, and the setting condition was 60 min at 40°C. The tensile strength and cooking yield of restructured pork sticks made with bisulfite-treated soy protein and MTGase were much higher than those of using salt, suggesting the high potential of using soy protein and MTGase as binders in products where NaCl reduction is desired.     

Quality characteristics of low-salt restructured poultry with microbial transglutaminase and seaweed

Characteristics of restructured poultry steaks as affected by addition of Sea Spaghetti seaweed (3% dry matter) combined with NaCl reduction and a microbial transgutaminase/caseinate (MTGase/caseinate) system as a cold binding agent were studied during chill storage. The incorporation of Sea Spaghetti caused a slight (P<0.05) increase in purge loss but reduced cooking loss in the products. Addition of MTGase/caseinate did not affect water binding properties. The added seaweed and the MTGase/caseinate system both increased (P<0.05), the Kramer shear force (KSF) of raw products, making them easier to handle. No such effect was observed in cooked products. Products with Sea Spaghetti had higher levels (P<0.05) of total viable counts and lactic acid bacteria, and also higher levels of tyramine and spermidine. All products were judged acceptable by a sensory panel. During chill storage no important changes were found in the target properties due to composition.     

Influence of alginate and microbial transglutaminase as binding ingredients on restructured fish muscle processed at low temperature

BACKGROUND: In view of the increasing demand for fresh products in Western countries recently, there is considerable interest in commercialising restructured fish products having the appearance of fresh fish. A number of methods have been studied for the purpose of inducing cold gelification. Two of the most common methods, namely addition of alginates and addition of transglutaminases, have been studied mainly in connection with meat products. The present study deals with the use of alginate and transglutaminase as additives in cold gelification of minced hake (Merluccius capensis) muscle. The experiments were targeted on the effects of concentration and combined effects of additional additives on physicochemical characteristics and mechanical properties. RESULTS: As regards mechanical properties, the effectiveness of sodium alginate was improved by addition of a low concentration (1 g kg^?1) of calcium chloride (CaCl₂), whereas a higher concentration (10 g kg^?1) reduced the binding ability of the alginate. The presence of sodium caseinate (15 g kg^?1) in combination with microbial transglutaminase (MTGase) was important in helping to increase the work of penetration in fish gels induced at low temperature. Examination of the chemical properties of the muscle gels showed that sodium alginate did not establish covalent protein–protein bonds, while MTGase dramatically increased the number of covalent bonds formed between adjacent muscle proteins. CONCLUSION: With both ingredients, thermostable fish gels of good quality were produced at temperatures below 10 °C. Gels induced by sodium alginate were considerably improved by addition of 1 g kg^?1 CaCl₂. However, gels induced by MTGase were better suited for the preparation of restructured products. Copyright © 2008 Society of Chemical Industry     

Protein Oxidation at Different Salt Concentrations Affects the Cross‐Linking and Gelation of Pork Myofibrillar Protein Catalyzed by Microbial Transglutaminase

In a fabricated then restructured meat product, protein gelation plays an essential role in producing desirable binding and fat‐immobilization properties. In the present study, myofibrillar protein (MFP) suspended in 0.15, 0.45, and 0.6 M NaCl was subjected to hydroxyl radical stress for 2 or 24 h and then treated with microbial transglutaminase (MTGase) in 0.6 M NaCl (E : S = 1 : 20) at 4 and 15 °C for 2 h. Protein cross‐linking and dynamic rheological tests were performed to assess the efficacy of MTGase for mediating the gelation of oxidized MFP. MTGase treatments affected more remarkable polymerization of myosin in oxidized MFP than in nonoxidized, especially for samples oxidized at 0.6 M NaCl. Notably, the extent of MTGase‐induced myosin cross‐linking at 15 °C in oxidized MFP improved up to 46.8%, compared to 31.6% in nonoxidized MFP. MTGase treatment at 4 °C for MFP oxidized in 0.6 M NaCl, but not MFP oxidized in 0.15 M NaCl, produced stronger gels than nonoxidized MFP (P < 0.05). The final (75 °C) storage modulus (G′) of oxidized MFP gels was significantly greater than that of nonoxidized, although the G′ of the transient peak (～44.5 °C) showed the opposite trend. Overall, oxidation at high salt concentrations significantly improved MTGase‐mediated myosin cross‐linking and MFP gelation. This might be because under this condition, MTGase had an increased accessibility to glutamine and lysine residues to effectively initiate protein–protein interactions and gel network formation.     

Using Salt and Microbial Transglutaminase as Binding Agents in Restructured Fish Products Resembling Hams

ABSTRACT: Restructured products were obtained from fish paste of silver carp ( Hypophthalmichthys molitrix ) by massaging and cooking in ham presses. Assayed were 3 levels of salt (0 as control, 1, or 2%) and 3 levels of microbial transglutaminase (MTGase). Changes on solubility of pastes, mechanical properties, WHC, and SDS-PAGE of the cooked product were evaluated. MTGase needed the addition of NaCl to improve the mechanical properties of these restructured products. Better textural properties were obtained with 2% NaCl. Adding 0.3% of MTGase and 1% NaCl obtained a low-salt, homogenous restructured meat block with 2773 g hardness, 29106 g/cm gel strength, 0.233 cohesiveness, and 11.6% extracted water.     

Evaluation of various salt levels and different dairy proteins in combination with microbial transglutaminase on the quality characteristics of restructured pork ham

The objective of this study was to evaluate the quality characteristics of restructured pork hams (RH) manufactured with various salt levels (0.5%, 1.0%, and 1.5%) and different dairy proteins (sodium caseinate, SC and whey protein isolate, WPI; 1.0%) in combination with microbial transglutaminase (MTGase; 0.3%). Reduced‐salt (0.5% and 1.0%) RH resulted in reductions of moisture contents (%), textural springiness, cooking yield and most sensory preferences (P < 0.05). When dairy proteins in combination with MTGase were incorporated into the manufacture of RH, SC with MTGase was shown to reduce cooking loss (CL, %) and to increase the textural springiness and chewiness of RH, whereas WPI with MTGase increased textural springiness and chewiness, as well as the shear value of RH (P < 0.05). On the contrary, MTGase with dairy proteins improved the sensory preferences of reduced‐salt (1.0%) RH to give it similar sensory properties to those of the regular‐salt (1.5%) RH controls (CTL) (P > 0.05). The findings of this study demonstrated that the combination of 1.0% dairy proteins and 0.3% MTGase could affect improvements in the functional, textural and sensory properties of reduced‐salt (1.0%) RH.     

Low‐salt restructured fish products using microbial transglutaminase as binding agent

Low‐salt restructured silver carp products were obtained using mechanically deboned fish meat from filleting wastes of silver carp (Hypophthalmichthys molitrix). The additives used were NaCl at three levels (0 (control), 10 and 20 g kg^?1) and microbial transglutaminase (MTGase) also at three levels (0 (control), 3 and 6 g kg^?1). The fish meat was massaged with the additives at <15 °C for 1 h. The massaged fish paste was then packed into steel stainless tubes and cooked at 40 °C for 30 min followed by 90 °C for 15 min. Changes in mechanical properties (texture profile analysis and punch test), solubility, electrophoretic profile and expressible water were evaluated. Hardness was in the range from 26.3 to 52.4 N, cohesiveness varied from 0.185 to 0.318 and springiness varied from 0.418 to 0.768. Increasing the amount of both additives improved the mechanical and functional properties of the restructured silver carp products. MTGase activity was associated with a decrease in protein solubility and a decrease in the myosin band (SDS‐PAGE). Increasing NaCl decreased the amount of expressible water. The results indicated that it is feasible to obtain low‐salt restructured silver carp products with improved mechanical and good functional properties using 3 g kg^?1 MTGase and 10 g kg^?1 NaCl. © 2002 Society of Chemical Industry     

微生物转谷氨酰胺酶催化聚合酪蛋白酸钠研究

研究了不同条件下微生物转谷氨酰胺酶 (MTGase)催化酪蛋白酸钠聚合。结果显示 ,MTGase较易催化α 以及β 酪蛋白 ,而不易催化κ 酪蛋白 ,随着酪蛋白量的不断下降 ,而形成的生物聚合物量不断增多。MTGase催化酪蛋白酸钠聚合的较佳条件如下 :酶量 /酪蛋白酸钠比例为 10～ 2 0U/g ,pH 6 0～ 8 0 ,最适催化温度为 37～ 5 0℃。     

Influence of the addition of mechanically recovered meat on the physico-chemical properties of meat model blends

The physico-chemical properties of meat model blends (basic composition: fresh lean pork, pork back fat, 2% NaCl, water with ice), with added mechanically recovered pork (MRM), were studied. Fresh MRM was added at levels of 10% and 20% substitution of meat protein with or without further substitution by 10% sodium caseinate or soya isolate. The addition of MRM to meat blends caused an increase in the pH, the water-holding capacity, the viscosity, the dominant wavelength and colour purity. No effects on emulsifying capacity were observed but thermal cooking losses and lightness of colour were reduced. The addition of blends of MRM and soya isolate or sodium caseinate caused lower values of the investigated features than those observed when only MRM was used.     

THERMO-RHEOLOGY,QUALITY CHARACTERISTICS,AND MICROSTRUCTURE OF FRANKFURTERS PREPARED WITH SELECTED PLANT AND MILK ADDITIVES1

The purpose of this study was to evaluate substitution of nonmeat proteins for meat protein on the thermo-rheology, quality characteristics, and microstructure of frankfurters. Batters were formulated to contain either 2% sodium caseinate or soy protein isolate, or 3.5% whey protein concentrate or wheat germ flour. The storage modulus (G') of all treatments initially decreased during temperature ramping from 20–50C, then increased rapidly from 60–80C, with all-meat batter exhibiting the highest G' at 80C. Substitution with nonmeat proteins decreased G', shear force, compression force, and red color of meat compared with all-meat frankfurters. Increased protein content, cooking yield, and decreased fat content were obtained with nonmeat protein formulations. Electron micrographs showed that nonmeat proteins were able to bind to the meat protein and fat, forming a protein-fat matrix with less coalescence of fat droplets. Sodium caseinate, soy protein isolate, whey protein concentrate, and wheat germ flour can be used as protein additives in comminuted meat products without adversely affecting their physical characteristics.     

Physical Characteristics and Microstructure of Reduced-fat Frankfurters as Affected by Salt and Emulsified Fats Stabilized with Nonmeat Proteins

Functional properties and microstructure of frankfurters containing 1.5% or 2.5% salt and 15% pre-emulsified fat (PEF) stabilized with 2% pea protein, soy protein, or sodium caseinate were studied. With the exception of frankfurters with pea protein and 1.5% NaCl, all the others made with PEF" had greater (p < 0.01) thermal stability than all-meat frankfurters. Frankfurters containing soy protein or sodium caseinate had greater (p < 0.01) shear force than those with pea protein. Reducing NaCl in the frankfurters containing PEF did not influence the shear force. Microstructure examination revealed that many fat globules were entrapped physically within soy protein or sodium caseinate, which stabilized the meat emulsions and contributed to a firmer texture. Key Words: emulsified fat, reduced-fat, low-salt, microstructure, frankfurters     

Physicochemical characteristics, textural properties and volatile compounds in comminuted sausages as affected by various fat levels and fat replacers

Physicochemical and textural properties, and volatile compounds of comminuted sausages with various added fat levels and fat replacers were evaluated. Sausages without added fat had higher expressible moisture and texture values, but their lightness and yellowness values were lower, as compared with sausages with 5%, 10%, or 15% fat. Increased fat levels with constant amounts of lean meat and added water increased the lightness and yellowness values, but tended the redness values tended to be similar. Low‐fat sausages (LFSs, <3%) containing non‐meat proteins, except egg white protein, had reduced texture values similar to those of regular‐fat counterparts (RFC). The addition of non‐meat proteins, except egg white protein, as components of fat replacers in LFS improved the textural characteristics, making them similar to those of RFC. LFSs containing sodium caseinate had reduced concentrations of pentadecanal and octadecanal, resulting in similar volatile compositions to those of RFC. Thus, sodium caseinate was the best non‐meat protein for the improvement of both texture and flavour of LFSs.     

Determination of the maximum feasible proportion in the substitution of meat substances by protein isolates in combined meat products

The author discusses the experimental data obtained during studies on male Wistar rats on the biological value of combined meat products (20 samples) including soybean protein isolate, sodium caseinate, and blood plasma proteins. The replacement proportions were 0, 12.5, 25, 50 and 100%. A definite dependence was ascertained between the biological value of total proteins in combined meat products and the replacement proportions. The replacement of meat proteins by soybean protein isolate (not over 25%), by sodium caseinate (by 50%) and by blood plasma proteins (not over 25%) and by a mixture containing 3 proteins (soybean, lactic, plasma) did not reduce the biological value of these combined meat products as compared to control.     

Use of microbial transglutaminase and sodium alginate in the preparation of restructured fish models using cold gelation: Effect of frozen storage

Changes in physicochemical properties of raw-appearing restructured models made from hake (Merluccius capensis) muscle, using cold gelation technology by addition of sodium alginate and microbial transglutaminase (MTGase), were studied during frozen storage at ? 15 °C.Among the more interesting results, addition of MTGase produced more protein aggregation in models processed by muscle homogenization and thus the protein network that formed in the gel was better than in samples with added sodium alginate. All samples presented enhanced changes in mechanical properties such as gel strength in the course of frozen storage. The protein network that formed was better organized as shown by the ultrastructure analysis and by protein aggregation data from the beginning of storage, and as a result Water Binding Capacity was greater in restructured models processed by muscle homogenization. Some of the models studied presented lipid oxidation during frozen storage, slightly more in the ones with MTGase added.Industrial RelevanceThe industrial relevance of the present work is to establish bases for using fish fillet trimmings and minced muscle to prepare restructured products that can be commercialized in a raw state and that could also support frozen storage in order to prolong the self-life in the market. The models studied here are not final products but the base with which to prepare them. One possibility of them is to process this kind of products with technologies normally used in whole fish muscle such as smoked fish fillets, carpaccios or marinated products. In addition, these raw restructured products can be commercialized to be cooked as a normal fresh fish fillet or pieces of fillet in a variety of preparations, and also products that contain a high amount of salt. Samples elaborated by binding larger muscle fragments imitate well the original fibrousness of the muscle so that it could be used to elaborate products similar to hamburgers or others that will be fried in batter.     

Comparative study of the functional properties of bovine globin isolates and sodium caseinate

Two methods used for extraction of globin from bovine blood were tested in terms of effiency, protein recovery and solvent residues. A comparative study with commercial sodium caseinate was made concerning the chemical composition and the functional properties of these proteins. Also, the effect of the NaCl addition on these properties was evaluated. Although the efficiency of the carboxymethyl-cellulose method was inferior than that of the acidified acetone, the absence of residual organic solvents in the globin makes it a more reliable method to prepare globins to be used in foodstuff. The chemical composition of proteins was affected by the method of extraction and the iron content of the globin obtained by the former method was more than three times higher than that using CMC. In general, the NaCl additon was harmful for the functional properties of the studied proteins, mostly for a salt concentration close to that used in meat products (0.25 mol/l).     

Heat-induced aggregation of whey proteins in the presence of κ-casein or sodium caseinate

Aggregates were formed by heating mixtures of whey protein isolate (WPI) and pure κ-casein or sodium caseinate at pH 7 and 0.1 M NaCl. The aggregates were characterized by static and dynamic light scattering and size exclusion chromatography. After extensive heat-treatment at 80 °C for 24 h, almost all whey proteins and κ-casein formed mixed aggregates, but a large proportion of the sodium caseinate did not aggregate. At a given WPI concentration the size of the aggregates decreased with increasing κ-casein or sodium caseinate concentration, but the overall self-similar structure of the aggregates was the same. The presence of κ-casein or caseinate therefore inhibited growth of the heat-induced whey protein aggregates. The results were discussed relative to the reported chaperone-like activity of casein molecules towards heat aggregation of globular proteins.