Young-Hwa Hwang

Control of fresh meat quality through manipulation of muscle fiber characteristics

Variations of fresh meat quality exist because the quality traits are affected by various intrinsic and extrinsic factors. Because the meat quality is basically dependent on muscle fiber characteristics, numerous studies have reported the relationship between quality traits and fiber characteristics. Despite intensive research, the relationship is yet to be fully established, however, the present knowledge suggests several potential ways to manipulate muscle fiber characteristics to improve meat quality. The present paper reviews the definition of fresh meat quality, meat quality traits and variations of meat quality. Also, this review presents recent knowledge underlying the relationship between fresh meat quality traits and muscle fiber characteristics. Finally, the present work proposes several potential factors including breed, genotype, sex, hormone, growth performance, diet, muscle location, exercise and ambient temperature that can be used to manipulate muscle fiber characteristics and subsequently meat quality in animals.

The relationship between muscle fiber characteristics and meat quality traits of highly marbled Hanwoo (Korean native cattle) steers

To investigate the relationships between muscle fiber characteristics and meat quality traits of Korean native cattle, Hanwoo, Longissimus dorsi (LD), Psoas major (PM) and Semimembranosus (SM) muscles obtained from 18 Hanwoo steers and the muscle fiber characteristics were measured by histochemical analysis. Fiber number, area percentages and density of type IIA and IIB were lower in SM muscle, but higher in PM muscle than other muscles. LD muscle had higher pH(24h), L* value and fat content whereas SM muscle had lower L* value and fat content. The lowest WBSF with longer sarcomere length was observed in PM muscle, while SM muscle showed the highest WBSF with shorter sarcomere length. Consequently, the percentage of type I and IIB were highly correlated with meat quality traits and inversely correlated with fat content, L* value and WBSF. Fiber number and area percentage of type I had a positive correlation with fat content and L* value and a negative correlation with WBSF. These results suggest that Hanwoo steers had high marbling, more lightness and tenderness when the percentage of type I was high and the percentage of type IIB was low in muscle.

The physicochemical and microbiological characteristics of pork jerky in comparison to beef jerky

This study was carried out to compare the physicochemical and microbiological characteristics of beef and pork jerky, prepared from whole muscle of beef semimembranosus (BSM), pork semimembranosus (PSM), pork longissimus dorsi (PLD), and pork psoas major (PPM). The BSM and PSM jerky had higher moisture content, and PPM jerky had lower water activity than other jerky samples during 30days of storage at 25°C (P<0.05). Pork jerky samples had higher lightness value than beef jerky, while PSM jerky had higher pH value than other jerky samples (P<0.05). The shear force and TBARS values of PPM jerky were higher than those of other jerky samples (P<0.05). Saturated fatty acid (SFA, %) was significantly higher in the BSM jerky than others, while unsaturated fatty acid (UFA, %) was significantly higher in the PSM and PLD than BSM and PPM jerky samples (P<0.05). The PPM jerky showed a significant increase in UFA (%) during storage, and a significantly decrease in microbial count after storage of 30days (P<0.05).

Effect of Chilling Temperature of Carcass on Breast Meat Quality of Duck

An experiment was carried out to investigate whether variations in chill water temperature affect muscle shortening and meat quality in duck breast. Three chill water temperatures were applied to duck carcasses at 20 min postmortem for 30 min, including in ice water at 0 degrees C, in cold water at 10 degrees C, and in water at 20 degrees C. Results revealed that carcass temperatures were different (P < 0.05) at 50 and 120 min of postmortem with lower temperatures at the 0 degrees C treatment (P < 0.05). The pH over the first 24 h postmortem was not different (P > 0.05) among treatments, with the exception of 50 min postmortem. The pH of breast meat in the 0 degrees C treatment was higher (P < 0.05) than that of 20 degrees C treatment at 50 min postmortem (just after chilling). No other differences (P > 0.05) in pH existed among treatments. Drip loss, cooking loss, and moisture content were not different for breast meat samples that were chilled at different temperatures. Differences (P < 0.05) were found in CIE (L, a, and b) color values. Lightness (L) increased, whereas redness (a) decreased as the chill water temperature increased. Lower yellowness (b) was found in the breast meat samples at the 10 degrees C chill water temperature. However, shear force, sarcomere length, and protein solubility were not different (P > 0.05) among the breast meat samples chilled at different chill water temperatures. It may be concluded that chilling duck carcasses at different temperature ranges from 0 to 20 degrees C did not influence muscle shortening or meat quality, except in regard to breast meat color.

The Relationship between Chemical Compositions, Meat Quality, and Palatability of the 10 Primal Cuts from Hanwoo Steer

The relationship between chemical compositions, meat quality traits, and palatability attributes in 10 primal cuts from Hanwoo steer carcasses were assessed. Sensory palatability attributes of Hanwoo beef were more closely related with fat content than to moisture or protein content. Among the chemical compositions, only fat had a significant correlation with juiciness (0.67, p<0.001), tenderness (0.32, p<0.05), and overall palatability (0.56, p<0.001). Oleic acid (%) was not significantly related with overall palatability (p>0.05). Overall palatability was negatively correlated with drip loss (−0.32, p<0.05), cooking loss (−0.36, p<0.05), and shear force (−0.54, p<0.01). The correlation between fat content and overall palatability was increased when higher fat cuts (Ansim, Dungsim, Chaekeut, Yangjee, and Kalbi) were analyzed, compared to lower fat cuts (Moksim, Abdari, Udun, Suldo, and Satae). Also, the correlation between shear force and overall palatability was decreased in lower fat cuts compared to higher fat cuts. Our results suggest that the palatability of Hanwoo beef can be improved by increasing fat content in muscles, as increased fat content leads to an increase in sensory tenderness, flavor, and juiciness.

Properties of duck meat sausages supplemented with cereal flours.

Duck meat sausages were prepared using 10% beef fat (FDS) and 10% hydrated cereal flours including rice (RDS), wheat, corn, millet, and barley to replace fat. Control duck sausages (DS) were also prepared only with duck meat and duck meat plus 10% beef fat. Results showed that protein and fat contents significantly decreased and total expressible fluid reduced with the addition of cereal flours in duck sausage batters. The FDS had higher fat content and lower pH compared with others. Duck sausages with 10% supplemented wheat flour showed the lowest cooking loss among sausages and had similar redness and chroma values to FDS and DS. Texture analysis indicated that hardness of duck sausage significantly decreased when cereal flours and beef fat were added. In particular, RDS showed the lowest values for all texture measurements compared with others. Result of moisture absorption capacity suggested that the decrease in hardness in RDS was due to higher moisture retention for rice flour treatment. Sensory evaluation indicated that DS had significantly lower overall acceptability than RDS, due to its off-flavor, whereas RDS had higher overall acceptability than DS.

Fatty Acid Profiles of Ten Muscles from High and Low Marbled (Quality Grade 1++ and 2) Hanwoo Steers

The aim of this research was to evaluate: 1) the fatty acid profile of ten muscles from high marbled (HM, quality grade 1++) and low marbled (LM, quality grade 2) Hanwoo carcass, 2) the relationship between the fatty acid profile and sensory traits. There were significant (p<0.001) differences in fat content and fatty acid composition among the 10 muscles obtained from HM and LM Hanwoo steers. The proportions of SFA (saturated fatty acid), MUFA (monounsaturated fatty acid) and PUFA (polyunsaturated fatty acid) were significantly (p<0.001) different among the 10 muscles due to differences in all fatty acids except eicosapentaenoic acid (EPA, C20:5n-3). The high-fat muscles had a lower n-6/n-3 ratio compared to the low-fat muscles (p<0.001). LM muscles had a significantly (p<0.05) higher proportion of SFA than HM muscles due to a higher proportion of stearic acid (C18:0). On the contrary, HM muscles had a significantly (p<0.01) higher proportion of MUFA than LM muscles due to higher oleic acid (C18:1n-9) proportion. SFA had a significant correlation with CIE a* (r=0.281; p<0.01) and drip loss (%) (r=−0.233; p<0.001). Cooking loss (%) had a significantly (p<0.05) negative correlation with PUFA (r=−0.233; p<0.05). Overall palatability was positively correlated with SFA (r=0.262; p<0.01), but negatively correlated with PUFA (r=−0.567; p<0.001). There was no significant correlation between oleic acid and any of the sensory traits (p>0.05).

Chemical Components and Meat Quality Traits Related to Palatability of Ten Primal Cuts from Hanwoo Carcasses.

To determine chemical components and meat quality traits related to palatability of 10 primal cuts, 25 Hanwoo carcasses were selected from 5 carcasses × 5 quality grades and used to obtain proximate data and meat quality characteristics. Significant differences (p<0.05) in chemical component and meat quality were found among the 10 primal cuts. The highest fat content was found in the kalbi, followed by dungsim, yangjee, chaekeut, ansim, abdari, suldo, moksim, udun, and satae. Protein and moisture contents in the 10 primal cuts were in reverse order of fat content. Moksim had the highest drip loss % and cooking loss % than all other primal cuts while kalbi showed the lowest (p<0.05) percentage of drip and cooking loss. Ansim had the longest sarcomere length but the lowest shear force values than all other cuts (p<0.05). The highest (p<0.05) score for overall acceptability was observed in ansim. Moksim, udun, abdari, and satae were rated the lowest (p<0.05) in overall acceptability among the 10 primal cuts from Hanwoo carcasses. In conclusion, ansim, dungsim, chaekeut, and kalbi had the highest overall acceptability due to their higher fat contents and lower shear force values.

Fatty Acid Profiles, Meat Quality, and Sensory Palatability of Grain-fed and Grass-fed Beef from Hanwoo, American, and Australian Crossbred Cattle

Fatty acid profiles in relation to meat quality traits and sensory palatability of grain-fed and grass-fed beef from Hanwoo, American, and Australian crossbred cattle were examined in this study. There were significant (p<0.001) differences in fat content and fatty acid compositions between grain-fed and grass-fed beef. Grain-fed Hanwoo had significantly (p<0.001) lower saturated fatty acid (SFA) proportion but higher monounsaturated fatty acid (MUFA) proportion compared to grass-fed cattle. The proportion of oleic acid in grain-fed Hanwoo was significantly (p<0.001) higher than that in grass-fed Hanwoo, Australian crossbred, or American crossbred cattle. Grain-fed Hanwoo had significantly (p<0.001) lower percentages of drip loss and cooking loss compared to other cattle. Overall palatability panel scores of grain-fed cattle were significantly (p<0.001) higher than those of grass-fed cattle. Consequently, sensory overall palatability was negatively correlated with proportions of SFA and polyunsaturated fatty acid (PUFA), but positively correlated with the proportion of MUFA. In particular, the proportion of oleic acid was strongly and positively correlated with fat content (r=0.91, p<0.001) and overall palatability (r=0.92, p<0.001). These results implied that high-concentrate grain-fed could increase intramuscular fat (IMF) content and the proportion of oleic acid, thus increasing the sensory palatability of Hanwoo beef.

The Relationships between Muscle Fiber Characteristics, Intramuscular Fat Content, and Fatty Acid Compositions in M. longissimus lumborum of Hanwoo Steers

The objective of this study was to investigate the relationship between muscle fiber characteristics, intramuscular fat (IMF) content, and fatty acids composition in longissimus lumborum (LL) muscle from Hanwoo steers. The LL muscles were obtained from four quality grades (QG) carcasses and subjected to histochemical analysis. There were significant (p<0.05) differences in fiber number percentage (FNP) and fiber area percentage (FAP) of muscle fiber types among muscles from four QGs. Both FNP and FAP of type I increased while those of type IIB decreased with increasing QG from QG 2 to QG 1++ (p<0.05). Also, with increasing QG, the saturated fatty acid (SFA) proportion decreased while monounsaturated fatty acid (MUFA) increased significantly (p<0.05). IMF content was positively correlated with both FNP and FAP of type I, but negatively correlated with those of type IIB. The proportions of SFA and MUFA were significantly (p<0.001) correlated with both type I and IIB composition. These results implied that muscle fiber type composition is an important factor influencing fatty acid composition in LL muscle of Hanwoo steer.