Ko-Eun Hwang

Physicochemical properties and sensory characteristics of reduced-fat frankfurters with pork back fat replaced by dietary fiber extracted from makgeolli lees

The effects of reducing pork fat levels from 30% to 20%, 15%, and 10% by partially substituting pork back fat with a makgeolli lees fiber were investigated regarding approximate composition, energy value, pH, color, cooking loss, emulsion stability, texture profile analysis, apparent viscosity, and sensory evaluation. The moisture and ash contents, redness, and yellowness were higher in reduced-fat frankfurters containing makgeolli lees fiber than in the control with 30% fat. With increasing fat levels, samples displayed higher pH, lightness, hardness, cohesiveness, gumminess, chewiness, apparent viscosity, and sensory quality, while displaying lower cooking loss and total expressible fluid. The results show that fat levels of frankfurters with added makgeolli lees fiber can be successfully reduced. Thus, 20% fat frankfurters with the addition of 2% makgeolli lees fiber are similar in quality to regular frankfurters with 30% fat.

Quality characteristics of reduced-fat frankfurters with pork fat replaced by sunflower seed oils and dietary fiber extracted from makgeolli lees

The effects of reducing pork fat levels from 30% to 20% by partially substituting pork fat with a mix of sunflower seed oil (0, 5, 10, 15, and 20%) and makgeolli lees fiber (2%) were investigated based on physicochemical properties, textural properties, and sensory characteristics of reduced-fat frankfurters. The moisture and ash content, and lightness were higher in reduced-fat frankfurter samples containing sunflower seed oil and makgeolli lees fiber than in the control. The results showed that reduced-fat frankfurter samples with higher sunflower seed oil levels had lower redness and yellowness values, as well as less cooking loss, emulsion stability, hardness, springiness, and apparent viscosity. The results of this study show that incorporating sunflower seed oil and makgeolli lees fiber into the formulation successfully reduced animal fat in frankfurters, while improving quality characteristics.

Effects of kimchi ethanolic extracts on oxidative stability of refrigerated cooked pork.

The antioxidant effect of different kimchi extracts in cooked ground pork during storage for 14 days at 4°C was studied. Cooked ground pork was treated with ascorbic acid, BHT, baechu kimchi (BK), got kimchi (GK), puchu kimchi (PK), and white kimchi (WK) and compared to cooked ground pork without antioxidant. Radical scavenging and chelating activities of kimchi extracts were in the order: GK>PK>BK>WK. Total phenolic contents and flavonoid contents ranged from 32.52 to 46.73 mg of GAE/g and 5.87 to 25.58 mg quercetin/g, respectively. Significantly (P<0.05) lower values of TBARS, peroxide values, and hexanal contents were obtained for GK treated samples compared with cooked pork without antioxidant during refrigerated storage. GK showed good antioxidant activity and was significantly different (P<0.05) from the other treatments. Based on these findings, the natural antioxidants examined may have applications in the development of nutritionally enhanced meat products with enhanced shelf life.

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 kimchi and smoking on quality characteristics and shelf life of cooked sausages prepared with irradiated pork.

The combined effects of kimchi powder (KP) and smoking (SM) on the quality characteristics and shelf life of cooked sausage prepared with 10 kGy irradiated pork (IP) were studied. The cooked sausages were formulated with single or combined treatment of 0.5% KP and SM (70°C for 30 min). IP+KP+SM treatment showed increased redness, hardness, gumminess, and chewiness, but decreased cooking yield. As for sensory evaluation, treatment with both KP and SM was effective to mask the radiolytic off-flavor. Moreover, the cooked sausage treated with both KP and SM had the highest color, flavor, and overall acceptance (P<0.05), where the differences of flavor patterns were verified by using an electronic nose. During chilled storage for 4 weeks, the combined treatment is effective to retard lipid oxidation, formation of volatile compound, and total microbial number due to the addition of KP. Therefore, usages of KP and SM can provide improved quality characteristics and shelf life of cooked sausage prepared with IP.

Antioxidant effects of soy sauce on color stability and lipid oxidation of raw beef patties during cold storage.

This study was conducted to evaluate the antioxidant effects of soy sauce on lipid oxidation and color stability of raw beef patties. Raw beef patties were formulated with four solutions such as NaCl (sodium chloride solution), NaCl/SS (1:1 ratio of sodium chloride and soy sauce solution), SS (soy sauce solution), or SS/A (soy sauce solution combined with 0.05% ascorbic acid) in the same salt concentration. Addition of soy sauce resulted in the decreased pH, lightness, and increased yellowness. Treatment SS/A had the lowest percent of metmyoglobin during storage (P<0.05). A reduction (P<0.05) in the 2-thiobarbituric acid, peroxide, and conjugated diene concentration as result of soy sauce addition were observed in treatments SS and SS/A at the end of the storage period. There were no differences (P>0.05) in free fatty acid concentration at the end of storage. The combined addition of soy sauce and ascorbic acid greatly improved (P<0.05) color stability and retarded lipid oxidation.

Antioxidant action of ganghwayakssuk (Artemisia princeps Pamp.) in combination with ascorbic acid to increase the shelf life in raw and deep fried chicken nuggets.

Raw and deep fried chicken nuggets containing various levels of ganghwayakssuk ethanolic extract (GE) in combination with ascorbic acid (Aa) were evaluated for shelf-life during refrigerated storage (4°C). The pH and color (lightness, redness, and yellowness) values of raw and deep fried samples were significantly affected by the addition of GE (P<0.05). All antioxidant combinations except for Aa+GE 0.01 were effective at delaying lipid oxidation (CD, POV, and TBARS) when compared to the control or Aa. Raw samples with GE 0.2 and Aa+GE 0.1 exhibited lower bacterial populations during storage. The sensory characteristics (color, juiciness, flavor, tenderness, and overall acceptability) did not differ significantly in all deep fried chicken nugget samples, except color, whereas storage time had a significant effect (P<0.05). The results suggest the possibility of utilizing raw and deep fried chicken nuggets with a mixture of ganghwayakssuk and ascorbic acid for the increase of shelf-life and quality.

Tenderization effect of soy sauce on beef M. biceps femoris

This study was conducted to evaluate the tenderization effect of soy sauce on beef M. biceps femoris (BF). Five marinades were prepared with 4% (w/v) sodium chloride and 25% (w/v) soy sauce solutions (4% salt concentration) and mixed with the ratios of 100:0 (S0, pH 6.52), 75:25 (S25, 5.40) 50:50 (S50, 5.24), 25:75 (S75, 5.05), and 0:100 (S100, 4.85), respectively. The BF samples which were obtained from Hanwoo cows at 48 h postmortem (n=24) were marinated with five marinades for 72 h at 4°C (1:4 w/w), and the effects of soy sauce on tenderness were evaluated. Soy sauce marination resulted in a decrease in the pH value of the BF sample. However, there were no significant differences in the water holding capacity (P<0.05). The S100 treatment showed the significant (P<0.05) increase in collagen solubility and myofibrillar fragmentation index, contributing to decreased shear force compared to S0 (control). Reduction in intensity of few myofibrillar protein bands were observed for S100 treatment compared to control using SDS-PAGE. Scanning electron microscopy revealed breakdown of connective tissue surrounding muscle fibers of the S100 treatment. The tenderization effect of soy sauce may attribute various mechanisms such as increased collagen solubility or proteolysis which depend on soy sauce level in marinade.

Effects of fat levels and rice bran fiber on the chemical, textural, and sensory properties of frankfurters

This study evaluated the effects of 5, 12, and 30% fat levels and the addition of rice bran fiber on the chemical, textural and sensory properties of low-fat frankfurters. Decreasing the fat content from 30 to 5% significantly increased cooking loss and decreased the amount of protein, the energy value, fat emulsion stability and hardness. Reduced fat frankfurters also exhibited increased lightness of the uncooked meat batter and cooked frankfurter. The addition of 2% rice bran fiber reduced the moisture, ash, carbohydrate, energy value, cooking loss, and total expressible fluid. Sensory evaluations indicated that frankfurters containing rice bran fiber had improved flavor and overall acceptability. Frankfurters with fat contents reduced from 30 to 12% and supplemented with 2% rice bran fiber had good textural attributes similar to the regular 30% fat control.

Antioxidative properties of onion peel extracts against lipid oxidation in raw ground pork

Onion peels extracted with various concentrations of ethanol were examined for their extraction yield, total phenolic content, DPPH scavenging activity, and reducing power. Onion peel extracted with 50% ethanol exhibited higher extraction yields, total phenolic content, and DPPH scavenging activity than extracts from distilled water, 70 or 95% ethanol. Thus, the antioxidative efficiency to inhibit lipid oxidation of ascorbic acid (0.05%) and 50% ethanol extract of onion peel (0.05, 0.1, and 0.2%) in raw ground pork was investigated during chilled storage (16 days). The pH of the samples decreased considerably during storage (p<0.05). Addition of ethanol onion peel extract significantly improved the thiobarbituric acid reactive substances and peroxide values in raw ground pork meat (p<0.05). Therefore, onion peel extract by 50% ethanol is a very effective inhibitor of lipid oxidation and has potential as a natural antioxidant in raw ground pork.