Youn-Kyung Ham

Effect of glasswort (Salicornia herbacea L.) on the texture of frankfurters

This study was aimed at evaluation of the effect of glasswort levels (0, 0.5, 1, and 1.5%) on the textural properties of frankfurters formulated with 0.75% NaCl. The addition of glasswort improved protein solubility (P<0.05) and apparent viscosity of frankfurters formulated with 0.75% NaCl, resulting in increased cooking yield and emulsion stability. This phenomenon might be mainly related to salts and dietary fiber within glasswort. In addition, the textural properties of frankfurter prepared with 0.75% NaCl and 1.5% glasswort showed similar properties (P>0.05) compared to those of control (1.5% NaCl). Our result suggests that the use of glasswort can be an effective approach to manufacture reduced-salt meat products. Moreover, the addition of 1.5% glasswort in frankfurters formulated with 0.75% NaCl is the optimum level without adverse effect on the texture.

Effects of Mechanically Deboned Chicken Meat (MDCM) and Collagen on the Quality Characteristics of Semi-dried Chicken Jerky.

This study was conducted to determine the effects of using mechanically deboned chicken meat (MDCM) and collagen on quality characteristics of semi-dried chicken jerky. In experiment I, semi-dried chicken jerky was prepared with the replacement of chicken breast with MDCM (0, 10, 20, and 30%). The pH value of the jerky formulated with only chicken breast was 5.94, while the replacement of chicken breast with MDCM significantly increased the pH (p<0.05). The protein content and shear force of the jerkies decreased with increasing amounts of MDCM, whereas the fat, ash content and processing yield showed the opposite tendency (p<0.05). Replacement with up to 10% MDCM had no adverse effects on the sensory characteristics of the semi-dried chicken jerky. In experiment II, four levels of pork collagen (0, 1, 2, and 3%) were added to the semi-dried chicken jerky formulated with 90% chicken breast and 10% MDCM. The addition of collagen increased the moisture content, but decreased the ash content of the jerkies produced (p<0.05). The processing yield of the jerkies increased with increasing added amounts of collagen (p<0.05). It was found that the jerkies formulated with 0-2% collagen had significantly higher overall acceptance score than those prepared with 3% collagen (p<0.05). In conclusion, MDCM and collagen could be useful ingredients to reduce the production cost and improve the processing yield of semi-dried chicken jerky. The optimal levels of MDCM and collagen which could be added without adverse effects on the sensory characteristics were up to 10% and 2%, respectively.

Effect of Pre-rigor Salting Levels on Physicochemical and Textural Properties of Chicken Breast Muscles.

This study was conducted to evaluate the effect of pre-rigor salting level (0-4% NaCl concentration) on physicochemical and textural properties of pre-rigor chicken breast muscles. The pre-rigor chicken breast muscles were de-boned 10 min post-mortem and salted within 25 min post-mortem. An increase in pre-rigor salting level led to the formation of high ultimate pH of chicken breast muscles at post-mortem 24 h. The addition of minimum of 2% NaCl significantly improved water holding capacity, cooking loss, protein solubility, and hardness when compared to the non-salting chicken breast muscle (p<0.05). On the other hand, the increase in pre-rigor salting level caused the inhibition of myofibrillar protein degradation and the acceleration of lipid oxidation. However, the difference in NaCl concentration between 3% and 4% had no great differences in the results of physicochemical and textural properties due to pre-rigor salting effects (p>0.05). Therefore, our study certified the pre-rigor salting effect of chicken breast muscle salted with 2% NaCl when compared to post-rigor muscle salted with equal NaCl concentration, and suggests that the 2% NaCl concentration is minimally required to ensure the definite pre-rigor salting effect on chicken breast muscle.

Effect of apple pomace fiber and pork fat levels on quality characteristics of uncured, reduced-fat chicken sausages

The effects of reducing pork fat level from 30 to 25 and 20% by partially substituting pork fat with 1 and 2% apple pomace fiber were investigated based on the evaluation of physicochemical properties and textural properties of uncured, reduced-fat chicken sausages. Increased fat level resulted in decreased moisture content, cooking loss, total expressible fluid separation, fat separation, and yellowness of uncured, reduced-fat chicken sausages, whereas, an increase in fat content, caloric energy, pH, lightness, redness, hardness, cohesiveness, gumminess, and chewiness was observed. The results showed that uncured, reduced-fat chicken sausage samples with increased apple pomace fiber level had lower cooking loss, total expressible fluid separation, fat separation, pH, and redness. The results from this study show that inclusion of apple pomace fiber in the formulation will successfully reduce fat content in emulsion sausages, while improving quality characteristics relative to regular-fat (30%) control.

Effects of Red and Green Glassworts (Salicornia herbacea L.) on Physicochemical and Textural Properties of Reduced-salt Cooked Sausages

This study was conducted to determine the effects of red and green glasswort on the physicochemical and textural properties of reduced-salt cooked sausages. The control was formulated with 1.5% NaCl; then, three reduced-salt treatments were prepared, with 0.75% NaCl (RS), 0.75% NaCl+1.0% red glasswort (RSR) and 0.75% NaCl+1.0% green glasswort (RSG), respectively. The addition of glasswort within the added amount of 1% had no influence on the pH value of the reduced-salt cooked sausages, regardless of the glasswort type. In terms of color, RSG treatment conveyed a higher hue angle value than the RSR treatment (p<0.05). Increases in the protein solubility (total and myofibrillar proteins) and apparent viscosity of reduced-salt meat batter that were due to the addition of glasswort were observed; however, there were no differences according to the type of glasswort (p>0.05). Furthermore, the addition of glasswort, regardless of its type, resulted in decreased cooking loss, and increased emulsion stability. As a result, reduced-salt cooked sausages formulated with either red or green glasswort demonstrated similar textural properties to those of the control. In conclusion, the type of glasswort within an added amount of 1% had no influence on the physicochemical and textural properties of reduced-salt cooked sausages, except for the color characteristics. In terms of color alteration by the addition of glasswort, the red glasswort, which in comparison with the green glasswort could minimize the color changes of reduced-salt cooked sausages, might be an effective source for manufacturing meat products.

Effects of Dietary Fiber Extracted from Pumpkin (Cucurbita maxima Duch.) on the Physico-Chemical and Sensory Characteristics of Reduced-Fat Frankfurters

In this study, we investigated the effects of reducing fat levels from 30% to 25, 20, and 15% by substituting pork fat with water and pumpkin fiber (2%) on the quality of frankfurters compared with control. Decreasing the fat concentration from 30% to 15% significantly increased moisture content, redness of meat batter and frankfurter, cooking loss, and water exudation, and decreased fat content, energy value, pH, and lightness of meat batter and frankfurter, hardness, cohesiveness, gumminess, chewiness, and apparent viscosity. The addition of 2% pumpkin fiber was significantly increased moisture content, yellowness of meat batter and frankfurter, hardness, cohesiveness, gumminess, chewiness, and apparent viscosity, whereas reduced cooking loss and emulsion stability. The treatment of reduced-fat frankfurters formulated with 20 and 25% fat levels and with pumpkin fiber had sensory properties similar to the high-fat control frankfurters. The results demonstrate that when the reduced-fat frankfurter with 2% added pumpkin fiber and water replaces fat levels can be readily made with high quality and acceptable sensory properties.

Effects of Replacing Sucrose with Various Sugar Alcohols on Quality Properties of Semi-dried Jerky

The objective of this study was to investigate the effects of replacing sucrose with sugar alcohols (sorbitol, glycerol and xylitol) on the quality properties of semi-dried jerky. Total 7 treatments of jerkies were prepared as follows: control with sucrose, and treatments with 2.5 and 5.0% of sucrose replaced by each sugar alcohol, respectively. Drying yield, pH, water activity, moisture content, shear force, myofibrillar fragmentation index (MFI), 2-thiobarbituric acid reactive substance (TBARS) value, sugar content, and sensory evaluation were evaluated. Xylitol slightly decreased the pH when compared to the other sugar alcohols (p>0.05). The water activity of the semi-dried jerky was significantly reduced by treatment with glycerol and xylitol (p<0.05). The moisture content of semi-dried jerky containing various sugar alcohols was significantly higher than that of the control (p<0.05), while replacing sucrose with glycerol yielded the highest moisture content. The shear force of semi-dried jerky containing sugar alcohols was not significantly different for the sorbitol and glycerol treatments, but that replacing sucrose with 5.0% xylitol demonstrated the lowest shear force (p<0.05). The TBARS values of semi-dried jerkies with sugar alcohols were lower than the control (p<0.05). The sugar content of the semi-dried jerkies containing sorbitol and glycerol were lower than the control and xylitol treatment (p<0.05). In comparison with the control, the 5.0% xylitol treatment was found to be significantly different in the sensory evaluation (p<0.05). In conclusion, semi-dried jerky made by replacement with sugar alcohols improved the quality characteristics, while xylitol has applicability in manufacturing meat products.

Effect of Ginger Extract and Citric Acid on the Tenderness of Duck Breast Muscles

The objective of this study was to examine the effect of ginger extract (GE) combined with citric acid on the tenderness of duck breast muscles. Total six marinades were prepared with the combination of citric acid (0 and 0.3 M citric acid) and GE (0, 15, and 30%). Each marinade was sprayed on the surface of duck breasts (15 mL/100 g), and the samples were marinated for 72 h at 4℃. The pH and proteolytic activity of marinades were determined. After 72 h of marination, Warner Bratzler shear force (WBSF), myofibrillar fragmentation index (MFI), pH, cooking loss, moisture content, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and protein solubility were evaluated. There was no significant (p>0.05) difference in moisture content or cooking loss among all samples. However, GE marination resulted in a significant (p<0.05) decrease in WBSF but a significant (p<0.05) increase in pH and MFI. In addition, total protein and myofibrillar protein solubility of GE-marinated duck breast muscles in both WOC (without citric acid) and WC (with citric acid) conditions were significantly (p<0.05) increased compared to non-GE-marinated duck breast muscles. SDS-PAGE showed an increase of protein degradation (MHC and actin) in WC condition compared to WOC condition. There was a marked actin reduction in GE-treated samples in WC. The tenderization effect of GE combined with citric acid may be attributed to various mechanisms such as increased MFI and myofibrillar protein solubility.

Effect of soy sauce type on the quality characteristics of emulsion sausages

The emulsion sausages were prepared with industrially brewed soy sauce at levels of 0, 1, 3, and 5%, and were additionally prepared with two further types of soy sauce (mixed and Korean traditional soy sauces) at a concentration of 1%. Soy sauce increased the satisfaction for flavor and saltiness of emulsion sausages. Addition of 1% soy sauce improved the overall acceptance without adverse effect on physicochemical and textural properties. From the results of electronic nose analysis, soy sauce results in an increased peak intensity of the emulsion sausages. In principal component analysis, clusters of emulsion sausages formulated with Korea traditional soy sauce and industrially brewed soy sauce were clearly distinct from the control (without soy sauce). Thus, our study suggested that addition of 1% soy sauce could be effective for improving the flavor of emulsion sausages, and the effects are highly dependent on the type of soy sauce used.

Effect of Duck Feet Gelatin Concentration on Physicochemical, Textural, and Sensory Properties of Duck Meat Jellies

This study was conducted to determine the effect of duck feet gelatin concentration on the physicochemical, textural and sensory properties of duck meat jellies. Duck feet gelatin was prepared with acidic swelling and hot water extraction. In this study, four duck meat jellies were formulated with 3, 4, 5, and 6% duck feet gelatin, respectively. In the preliminary experiment, the increase in duck feet gelatin ranged from 5 to 20%, resulting in a significant (p<0.001) increase in the color score, but a decline in the hardness and dispersibility satisfaction scores. An increase in the added amount of duck feet gelatin contributed to decreased lightness and increased protein content in duck meat jellies. Regarding the textural properties, increase in the added amount of duck feet gelatin highly correlated with the hardness in the center (p<0.01, R2=0.91), and edge (p<0.01, R2=0.89), of duck meat jellies. Meanwhile, the increase in duck feet gelatin decreased the score for textural satisfaction; duck meat jellies containing 6% duck feet gelatin had a significantly lower textural satisfaction score, than those containing 3% duck feet gelatin (p<0.05). Furthermore, a significant difference in the overall acceptance of duck meat jellies formulated with 5% duck feet gelatin was observed, as compared to those prepared with 3% duck feet gelatin. Therefore, this study suggested that duck feet gelatin is a useful ingredient for manufacturing cold-cut meat products. In consideration of the sensory acceptance, the optimal level of duck feet gelatin in duck meat jellies was determined to be 5%.