• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.69-76
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• 1998

This study was investigated to determine the effect of additives and ionic strength on the functionality of extracted proteins in preblends in order to use less additive in restructured meat products. Preblends contained the combinations of sodium chloride (NaCl; 0, 4.5, 9.0%), sodium tripolyphosphate (STPP; 0, 2.5, 5.0%), and tetrasodium pyrophosphate (PP; 0, 2.44, 4.88%). The pH values increased linearly with increasing STPP and PP concentrations (p<0.01). In the equivalent ionic strengths, PP was more effective than STPP in increasing pH. Phosphate ions were more effective on total extractable protein (used 1 M NaCl buffer) than chloride ion at equivalent ionic strengths. Solubility was decreased by adding NaCl and increasing total extractable proteins. Meat sulfhydryl contents were high with increasing total extractable proteins. When protein extracts were heated at $65^{\circ}C$, 7 min, meat sulfhydryl contents decreased and surface hydrophobicity increased (p<0.01). However, all protein extracts showed no differences in SDS-PAGE pattern. In conclusion, PP is more effective than STPP in order to use less additive but there was no linear relationship between functionnal improvement and ionic strength.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.650-663
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• 2021

The objective of this study was to examine the relationship between meat quality attributes and the changes of sarcoplasmic protein acetylation and myofibrillar protein acetylation in lamb longissimus thoracis et lumborum muscles at different postmortem phases. Protein acetylation, color, pH, shear force, myofibril fragmentation index and cooking loss were measured. The total level of acetylated sarcoplasmic proteins showed a negative relation with pH, a positive relation with a^*, b^* and cooking loss at the pre-rigor phase. Sarcoplasmic proteins acetylation affected postmortem pH by regulating glycolysis, which in turn affects color and cooking loss. The total level of acetylated myofibrillar proteins showed a positive relation with shear force at the pre-rigor phase. Myofibrillar proteins acetylation affected meat tenderness by regulating muscle contraction. This study indicated that acetylation played a regulatory role of meat color, water-holding capacity, and tenderization process at early postmortem.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.401-408
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• 1985

In order to develop new types of product which can offer a sanitary and preservative duality, and convenience to consumers in marketing and cooking particularly in urban area, two processing methods of ready-to-cook food materials with dark fleshed fishes like sardine and mackerel were investigated. A method applied, in this work, is processing of ready-to-cook sardine meat "surimi" in which sardine meat is treated with alkaline solution to stabilize myofibrillar proteins, washed thoroughly with water to remove soluble components, and added with a proper amount of polyphosphate and sorbitol to enforce the functional property of meat such as water holding capasity, elasticity, and gel strength. The textural properties of fish meat paste made from the "surimi" meat were greatly dependent upon the stability of myofibrillar proteins and the elimination of water soluble components. The salt soluble proteins of sardine meat were so unstable in post-mortem stage that the gel forming ability was lost within 3 days at $5^{\circ}C$ storage and 2 to 3 weeks even at $-20^{\circ}C$ although the freshness was well kept for a week at $5^{\circ}C$ and several months of storage at $-20^{\circ}C$. A proper way of treatment to keep the proteins stable was that fish meat must be washed with $0.4\%$ sodium bicarbonate solution followed by 3 to 4 times washing with water. This resulted in removal of $80\%$ water soluble proteins and 50 to $60\%$ lipids. The addition of polyphosphate and sorbitol affected the stability of proteins during the storage of "surimi" meat. When phosphate and sorbitol were added in the ratio of $0.3\%:\;0.3\%,\;0.6\%:\;3\%,\;0.6\%:\;6\%,\;0:\,0.3\%\;and\;0.3\%:\;0$, the gel forming ability terminated in 35 days, 21 days, 14 days, 14 days, and 14 days of storage at $-30^{\circ}C$, respectively, while that of the control was 7 days. And it was also noteworthy that at least 8.0 mg/g of salt soluble protein nitrogen content was required for gel formation.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.152-163
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• 2005

Lipid peroxidation is a primary cause of quality deterioration in meat and meat products. Free radical chain reaction is the mechanism of lipid peroxidation and reactive oxygen species (ROS) such as hydroxyl radical and hydroperoxyl radical are the major initiators of the chain reaction. Lipid peroxyl radical and alkoxyl radical formed from the initial reactions are also capable of abstracting a hydrogen atom from lipid molecules to initiate the chain reaction and propagating the chain reaction. Much attention has been paid to the role of iron as a primary catalyst of lipid peroxidation. Especially, heme proteins such as myoglobin and hemoglobin and "free" iron have been regarded as major catalysts for initiation, and iron-oxygen complexes (ferryl and perferryl radical) are even considered as initiators of lipid peroxidation in meat and meat products. Yet, which iron type and how iron is involved in lipid peroxidation in meat are still debatable. This review is focused on the potential roles of ROS and iron as primary initiators and a major catalyst, respectively, on the development of lipid peroxidation in meat and meat products. Effects of various other factors such as meat species, muscle type, fat content, oxygen availability, cooking, storage temperature, the presence of salt that affect lipid peroxidation in meat and meat products are also discussed.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.611-614
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• 2015

This study was performed to apply a protein film containing a natural antimicrobial compound to meat packaging and determine quality change of meat during storage. Proteins obtained from the by-products of food processing have been utilized as biodegradable film sources. Porcine meat and bone meal (MBM) is obtained during meat processing, and proteins from the MBM can be extracted and used as a film base material. Previously, an antimicrobial MBM film containing coriander oil (CO) was prepared and its physical properties and antimicrobial activity were characterized. In this study, the antimicrobial MBM-CO film was applied to beef patties packaging, and the microbial population and the degree of lipid oxidation were determined during storage at 4℃ for 15 d. The population of inoculated E. coli O157:H7 in the samples wrapped with the MBM-CO film was 6.78 log colony forming unit (CFU)/g after 15 d of storage, whereas the control had 8.05 Log CFU/g, thus reducing the microbial population by 1.29 Log CFU/g. In addition, retardation of lipid oxidation in the patties was observed during storage for the samples packaged by the MBM-CO film, compared with the control samples. These results suggest that the MBM-CO film can be useful for enhancing the quality of beef patties during storage.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.407-412
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• 1998

The proteins extracted from beef, pork and chicken meats were irradiated with up to 100 kGy at room temperature. The extracted proteins were evaluated on their in vitro digestibility by incubating successively with pepsin and pancreatin conjugate. Amino acid compositions and SDS-PAGE pattern were also analyzedin for these proteins. Gamma irradiation within the applied dose range (up to 100 kGy) produced negligible in in vitro digestibility and amino acid composition. Analysis of gamma-irradiated proteins by SDS-PAGE revealed radiolysis of ovalbumin to proteins or peptides with lower molecular weight. On the other hand, the proteins directly extracted from irradiated meats containing moisture were also evaluated for their in vitro digestibility, amino acid compositions and SDS-PAGE pattern. However, the results obtained from this experiment were similar to those of irradiated proteins after extraction from the meats.

• Food Science of Animal Resources
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• v.22 no.4
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• pp.363-372
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• 2002

Reducing the fat content of processed meat products can be performed by (1) using leaner raw meat materials (2) inducing non-meat ingredients that serve to replace a portion or all of the fat, and (3) applying new ingredient combinations, technologies or processing procedures that decrease the fat and cholesterol content of meat products. Low-fat meat products were manufactured with Int replacers which were food ingredients that had the functional and sensory properties of fat without contributing fat calories, resulting in lower fat(<3%) content. Added water, non-meat proteins, carbohydrates, such as starch and hydrocolloids(gums) and vegetable oils have been used as typical fat replacers to be used in meat products. In addition, fat substitutes included structural lipids, sucrose polyester and ingredient combinations. Formulations for the manufacture of low-fat meat products in combined with new technologies have focused on the use of fat replacer combinations that contributes a minimum of calories and not detrimental to flavor, juiciness, mouthfeel or textural traits expected more traditional products. In conclusion, some combinations of fat replacements that mimics the flavor, mouthfeel and textural characteristics of fat offer potential for further development of low-fat meat products to have similar characteristics of regular-fat counterparts.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.301-307
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• 2012

We investigated the effects of non-meat protein binders combined with glucono-${\delta}$-lactone (GdL) on the binding properties regarding restructured pork prepared by high-pressure treatment. Soy protein isolate (SPI), casein (CS), whey protein concentrate (WPC), and egg white (EW) were used as non-meat protein binders and compared with the control (no binder) and with the ${\kappa}$-carrageenan (KC) treatment. The compression and depression rates were 2.3 and 37 MPa/s, respectively, and pressurization was conducted at 200 MPa for 30 min at $4^{\circ}C$. After pressurization, the physical properties (pH, water-holding capacity, color, tensile strength, and microscopic structure) of the sample were evaluated. The combination of pressurization with acidification enabled cold-set meat binding, and the binding strength of restructured pork was enhanced by the addition of non-meat proteins. Among binders, SPI demonstrated the best efficiency in binding meat pieces. Therefore, the present study demonstrated that the combination of acidification and pressurization processes with the utilization of non-meat protein binders has a potential benefit in meat restructuring.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.39-45
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• 2001

The pork meat has been reported as one of the food occurring allergic reactions predominantly to korean. To identify the potential food allergens in pork meat, sera were collected from 25 allergic patients to the pork meat and 10 allergic patients not to pork meat as well as 5 normal subjects after skin prick test and open food challenge test. Crude extracts were prepared by blending raw pork meat in phosphate buffered saline (pH 7.0) and the heat treatment on crude extracts was carried to characterize sensibility of the allergens to heat. ELISA was performed to determine specific IgE antibody levels of allergic patients to pork meat, and resulted in twofold higher mean value than that of tolerated patients. Extracted proteins from pork meat was separated with SDS-PAGE followed by immunoblotting using sera from pork sensitive patients and control subjects, respectively. The IgE binding response to pork meat by immunobots correlated with quantitative specific IgE value of each person. Immunoblots showed four prominent IgE-binding bands (66, 60, 50, 44 kDa) in crude extract, but two bands of those (60, 44 kDa) were heat-labile. These results suggest that most prominent allergens from pork meat are four components(66, 60, 50, 44 kDa) in korean and the heat treatment on allergen is additional parameter to characterize allergen.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1611-1620
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• 2019

Objective: The aim was to investigate the influence of ultrasound and adenosine 5'-monophosphate (AMP) marination (UAMP) on tenderness and structure of myofibrillar proteins of beef. Methods: Five groups, the untreated meat (Control), deionized water marination (DW), ultrasound followed by DW (UDW), AMP marination (AMP), and ultrasound followed by AMP (UAMP) were studied. Myofibrillar fragmentation, cooking loss, shear force, thermograms, histological observation of meats and myofibrillar proteins properties were investigated in these different treatments. Results: The results showed that UAMP significantly increased myofibrillar fragmentation index from 152 (Control), 231 (AMP), and 307 (UDW) to 355 (p<0.05), respectively. The lowest cooking loss, shear force and peak denaturation temperature were observed in UAMP. In histological observation, UDW and UAMP had more fragmented muscular bundles than the others. Furthermore, a drastic increase in ${\alpha}$-helix and decrease in ${\beta}$-sheet of myofibrillar proteins was observed in UAMP, implying the disaggregation of protein samples. The synchronous fluorescence spectra of myofibrillar proteins in UAMP suggested the combination of ultrasound and AMP could accelerate the unfolding molecular structure and destroying hydrophobic interactions. The results of circular dichroism and synchronous fluorescence spectra for myofibrillar proteins coincided with the microstructures of beef. Conclusion: The results indicate that ultrasound combined with AMP improved meat tenderness not only by disruption in muscle integrity, increasing water retention, but also altering their spatial structure of myofibrillar proteins.