• Journal of Life Science
• /
• v.26 no.8
• /
• pp.955-962
• /
• 2016

Fish-meat gel is an intermediate product used in a variety of surimi-based seafood. One of the most-used raw materials of fish-meat gel is Alaska Pollock due to its high-quality meat in terms of gel strength and texture. However, increasing demand for fish-meat gel, along with overexploitation of the wild catch Alaska Pollock, has put the industry in need of low-cost sustainable alternative sources for fish-meat gel. Pagrus major (PM) is a widely aquacultured fish known for having white meat that is low in fat. The current study compares the quality of fish-meat gel prepared from aquacultured PM to that of high and mid-grade Alaska Pollock fish-meat gel. Gels were compared in terms of gel strength, texture, color, and protein pattern. Results indicated that fish-meat gels prepared from PM were superior to Alaska Pollock fish-meat gels with regard to gel strength, hardness, springiness, chewiness, cutting strength, and breaking force. In addition, although not matching in quality, PM exhibited a cohesiveness, whiteness, and expressible moisture content comparable to Alaska Pollock of both grades. Protein pattern analysis also showed that PM and Alaska Pollock fish-meat gels had similar protein profiles before and after gel preparation. Therefore, P. major is suggested as a potential substitute for Alaska Pollock in fish-meat gel production.

• Journal of Life Science
• /
• v.19 no.7
• /
• pp.994-1002
• /
• 2009

A bacteriocin-producing bacterium identified as Bacillus licheniformis was isolated from soybean sauce. Antibacterial activity was confirmed by paper disc diffusion method, using Micrococcus luteus as a test organism. The bacteriocin also showed antibacterial activities against Bacillus sphaericus, Lactobacillus bulgaricus, Lactobacillus planiarum, Paenibacillus polymyxa, and Pediococcus dextrinicus. Optimal culture conditions for the production of bacteriocin was attained by growing the cells in an MRS medium at a pH of 6.5~ 7.0 and a temperature of 37$^\circ$C for 36$\sim$48 hr. Solvents such as chloroform, ethanol, acetone, and acetonitrile had little effect on bacteriocin activity. However, about 50% of bacteriocin activity diminished with treatment of methanol and isopropanol at the final concentration of 50% at 25$^\circ$C for 1 hr. It was stable against a pH variation range from 3.0 and 7.0, but the activity reduced to 50% at a pH range from 9.0 to 11.0. It's activity was not affected by heat treatment at 100$^\circ$C for 30 min and 50% of activity was retained after heat treatment at 100$^\circ$C for 60 min, showing high thermostability. The bacteriocin was purified to a homogeneity through ammonium sulfate precipitation, SP-Sepharose ion-exchange chromatography, and reverse-phase high-performance liquid chromatography (HPLC). The entire purification protocol led to a 75-fold increase in specific activity and a 13.5% yield of bacteriocin activity. The molecular weight of purified bacteriocin was estimated to be about 2.5 kDa by tricine-SDS-PAGE.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.1
• /
• pp.35-41
• /
• 2006

Antibacterial activities of the trace elements in combination with the food additives were measured against 6 kinds of food-borne microorganisms such as Escherichia coli, Vibrio parahaemolyticus, Staphylococcus aureus, Bacillus cereus, Bacillus subtilis and Pseudomonas fluorescens. The difference of antibacterial activity was not shown among the kinds of food additives, such as dextrin, gelatin and collagen. Zn and Ge in combination with food additives had strong antibacterial effect. Especially, $1\%$ zinc acetate in combination with $1\%$ gelatin was more effective against P. fluorescens and S. aureus than against Bacillus sp., E. coli and V. parahaemolyticus. Minimum inhibitory concentration of zinc acetate in combination with $1\%$ gelatin appeared to be 0.5 mg/mL on S. aureus and P. fluorescens, and 1.0 mg/mL on E. coli, V. parahaemolyticus, B. cereus and B. subtilis. Minimum bactericidal concentration of zinc acetate in combination with $1\%$ gelatin appeared to be 0.5 mg/mL on P. fluorescens and 1.0 mg/mL on E. coli, V. parahaemolyticus, S. aureus, B. cereus and B. subtilis. The zinc acetate in combination with gelatin showed stronger inhibitory effect in acidic range below pH 6.0, and remained active even after heat treatment at $121^{\circ}C$ for 15 min. In comparison with control, the viable cell counts of fish pastes, which were coated with the solution containing both $1\%$ zinc acetate and $3\%$ gelatin, were decreased by more than 100-fold until the storage of 7 days at $10^{\circ}C$. The results indicate that the combined use of zinc acetate and some food additives could prolong the shelf life of fish pastes by 8 days or more at $10^{\circ}C$.

• Korean Chemical Engineering Research
• /
• v.56 no.2
• /
• pp.261-268
• /
• 2018

To prepare mesoporous $TiO_2$ ($meso-TiO_2$) with anatase and rutile crystal structures, hydrothermal and template synthesis were used. $Meso-TiO_2$ with anatase structure was obtained by hydrothermal synthesis. The crystal structure of $meso-TiO_2$ by hydrothermal synthesis converted from anatase to rutile by simple heating at $600^{\circ}C$ and above. However, their mesopore structure collapsed due to phase transition. To prepare $meso-TiO_2$ with rutile structure, template synthesis method was applied using mesoporous silica KIT-6 as a template. Once we incorporated anatase $TiO_2$ inside mesopores of silica, the phase transition temperature of $TiO_2$ confined inside KIT-6 was much higher ($900^{\circ}C$) than that of free-standing $TiO_2$ ($600^{\circ}C$). The suppression of $TiO_2$ phase transition inside mesopores of KIT-6 is closely related with the interaction between $TiO_2$ surface and silica walls in KIT-6 because oxygen vacancy in $TiO_2$ is regarded as the starting point for phase transition. After removal of silica template by NaOH solution washing, $meso-TiO_2$ with mixed phase between anatase and rutile was obtained.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.5
• /
• pp.618-625
• /
• 2009

The purposes of this study were to evaluate food safety knowledge and to assess home food safety performance of home-delivered meal service recipients. Two facilities providing home-delivered meal services for older adults were located in Seoul. A total of 120 service recipients were surveyed using an individual interview technique and 97 responses were used for data analysis. A statistical data analysis was completed using SPSS program (ver.14) for descriptive analysis, t-test, ANOVA, and correlation analysis. The majority of the participants were 70 years old or older and females. They perceived their health status as poor or very poor and took more than one kind of medicines. An average score of the food safety knowledge test was 11.48 based on 18 points (63.8%). The results revealed that the older adults knew the importance of hand washing but were not aware of when and how to wash hands. There was room to improve knowledge on cleaning and sanitizing fresh fruits and using wiping cloth. The knowledge score for each category was not significantly different by gender and age. The home food safety practices of the older adults was rated as 2.8 out of 4 points; the highest score was associated for proper food handling category and the lowest score was for cleaning and sanitizing. The worst performance was related to managing hand cuts and wounds (1.96). The total knowledge score and an average performance score were significantly correlated (p<0.01). Food safety education programs targeting the older adults who receive home-delivered meal services would improve the recipients' food safety knowledge and practices related to consumption of the meals at home. The programs should focus on not only improving food safety knowledge but also changing food safety practices.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.5
• /
• pp.774-783
• /
• 2013

This study investigated the quality characteristics of boiled pork with different amounts (0.5, 1, 1.5, or 2%) of green tea, oolong tea and black tea extracts. Characteristics measured included approximate composition, water holding capacity (WHC), hardness, pH, Hunter's color value, total aerobic bacterial counts, volatile basic nitrogen (VBN), 2-thiobarbituric acid reactive substances (TBARS), and sensory qualities. Green tea approximately contained 3.4%, 31.8%, 5.5%, and 57.7% of moisture, crude protein, crude ash, and carbohydrate, respectively. There were no significant differences with the type of tea. However, the crude fat content of green tea, oolong tea, and black tea were 1.6%, 1.0%, and 0.9%, respectively. Green tea had the highest content of crude fat (p<0.05). Boiled pork approximately contained 55.1%, 38.6%, 5.2% and 0.9% moisture, crude protein, crude fat and crude ash, respectively. The WHC of boiled pork, with tea extract added, significantly increased and there were no significant differences according to the type of tea. The hardness of boiled pork significantly increased as the amount of tea extract added increased (p<0.05). The pH of the boiled pork was not significantly different after storage for one day, but significantly decreased in control groups and boiled pork with 0.5% of any tea extract added during storage. However, in boiled pork with 1%, 1.5%, or 2% of any tea extract added, pH was not significantly different during storage. The Hunter's L and b values decreased in all boiled pork. The Hunter's a-values also decreased in boiled pork with green and black tea extract added, but increased in boiled pork with oolong tea extract added. In boiled pork with tea extract added, total aerobic bacterial counts significantly decreased as the amount of tea extract added increased during storage (p<0.05). The VBN values significantly increased during storage in all groups. TBARS values were significantly lower in boiled pork with green tea extract added, oolong tea added (at concentrations of 1%, 1.5%, or 2%), and black tea extract added compared to control groups on the first day. The sensory evaluation results showed that the color, flavor, and overall acceptance of boiled pork containing 1% of oolong or black tea extracts had the highest scores but there were no significant differences. However, taste scores were significantly different (p<0.05). These results indicate that boiled pork has improved quality characteristics with 1% of oolong or black tea extracts added.

• Journal of the Korean Home Economics Association
• /
• v.29 no.4
• /
• pp.25-35
• /
• 1991

This study was carried out to determine the proximate composition, amino acids and fatty acids contents and changes of physicochemical characteristics of each oil extracted from Spanish and Virginia type peanuts grown in Korea roasted at 110, 120, 130 and 14$0^{\circ}C$ for 2 minutes. 1. The moisture contents of raw Spanish and Virginia type peanuts were 6.5~6.8% respectively. The crude ash and reduced sugar contents of raw Spanish and Virginia type peanuts were 2.3% and 16.5% and the crude protein content was 27.0% in Spanish type peanuts and was aproximately 1% higher than in Virginia type peanut. The protein content was 25.7%~26.7% in Virginia type peanut roasted at 110, 120, 130 and 14$0^{\circ}C$. The crude fat content of Virginia type peanut was 46.0% which was aproximately 1% higher than that of Spanish type. But four kinds of oils content were 51.3%~51.8% in Spanish type peanut roasted at 110, 120, 130 and 14$0^{\circ}C$, which was about 2% higher than those of Virginia type. 2. Amino acids existed in peanut were glutamie acid, arginine, aspartic acid, leucine, glycine, phenylalanine, proline-lysine, tyrosine, valine and isoleucine, etc mainly. But methionine and threonine contents were very low. The content of glutamic acid was the highest in 71.6-81.7mg among amino acids. Glutamic acid content of Virginia type peanut was about 12% higher than that of Spanish type peanut. Total amino acid content was 441.8mg/g in Virginia type peanut and that was 16% higher than that of Spanish type peanut. The lysine content of Spanish and Virginia type peanuts roasted at 14$0^{\circ}C$ were 24% and 13%, these were lower than those of peanuts roasted at 11$0^{\circ}C$. 3. Main fatty acids of raw Spanish and Virginia type peanut oils were oleic(40.99-46.58%), linoleic(33.21-38.82%) and palmitic acid(9.72-11.58). Linoleic acid content of raw Virginia type peanuts was 5.6% higher than that of raw Spanish type peanut. And the oleic acid content of Spanish and Virginia type peanuts roasted at 11$0^{\circ}C$, 12$0^{\circ}C$, 13$0^{\circ}C$ and 14$0^{\circ}C$ was 50-53% and 41-43% respectively. Linoleic acid content of Spanish and Virginia type peanuts roasted at same temperatures as the former was about 28-31% and 37-38% respectively. That linoleic acid content of roasted peanuts was lower than that of raw peanuts. Linoleic acid content of raw and roasted Virginia type peanut, were higher than that of Spanish type peanuts. 4. Acid value and peroxide value of oils extracted from roasted Spanish and Virginia type peanuts were much higher than those of oils extracted from raw peanuts. The maximum AVs of oils extracted from Spanish and Virginia type roasted peanuts were samples roasted at 12$0^{\circ}C$and those AVs were 0.50 and 0.63 respectively. And the maximum POVs of oils extracted from Spanish and Virginia type roasted peanuts were samples roasted at 12$0^{\circ}C$ also and those POVs were 26.8 and 32.8 meq/kg. oil respectively. Acid value and peroxide value of oils extracted from roasted peanuts were increased with increasing the roasting temperatures from 11$0^{\circ}C$ to 12$0^{\circ}C$, then decreased, while TBA values were increased continuously with increasing the roasting temperatures.

• Korean Journal of Food Science and Technology
• /
• v.41 no.1
• /
• pp.57-63
• /
• 2009

In this study, seasoning sauces were prepared with Geranium thunbergii sieb. et Zucc. (1%, PGT), Crataegi fructus (1%, PCF) and their combination (0.5% PGT + 0.5% PCF, bPMGC) and then the quality characteristics of the sauces and seasoned pork were investigated. The lightness, redness and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of the sauces were increased by the addition of Crataegi fructus. Sensory qualities such as taste, color and overall acceptability were scored higher in the sauce prepared with Crataegi fructus than the control. The viable cell counts of pork seasoned with the various sauces were 5.04 CFU/g (control), 4.59 CFU/g (PGT), 3.88 CFU/g (PCF) and 4.38 CFU/g (PMGC) after storage for 15 days at $4^{\circ}C$, respectively. The coliform count of the control pork was below 1.0 CFU/g after storage for 25 days and coliform were not detected in PGT, PCF and PMGC after storage for 10 days at $4^{\circ}C$. The thiobarbitunc acid reaotive substance values of PGT, PCF and PMGC were significantly lower than that of control, but volatile basic nitrogen contents were not significantly different between the treated and untreated pork samples during storage. Cooking loss increased in all treatments during storage for 25 days and their water holding capacity increased during storage for 10 days and decreased thereafter. The lightness, redness and yellowness values of PCF were higher than those of the control. The sensory qualities of PCF, including taste, color and overall acceptability, were significantly improved compared to the control. Finally, the pork seasoned with the sauce containing 1% Crataegi fructus extract had significantly improved shelflife, water holding capacity, inhibition of rancidity, color and sensory quality.

• Korean Journal of Food Science and Technology
• /
• v.41 no.4
• /
• pp.386-391
• /
• 2009

To verify the possibility of manufacturing a germinated rough rice tea, germinated rough rice was roasted at 200, 220, and $250^{\circ}C$ for 10, 20, and 30 min. The treated rice powder was then put into tea bags and leached for 1, 3, and 5 min, after which their antioxidant, physicochemical, and sensory characteristics were compared. The total polyphenol content and 2,2'-Azino-bis-(3-ethyl benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of the germinated rough rice tea increased as the roasting temperature increased as well as in response to increased roasting and leaching times. Furthermore, the greater the roasting temperature, roasting time, and leaching time, the greater the increase in total soluble solid contents. Moreover, the turbidity and browning index of the germinated rice tea rose as the roasting temperature, roasting time, and leaching time increased. Additionally, the pH tended to decrease as the roasting temperature, roasting time, and leaching time increased. Evaluation of the sensory characteristics of the germinated rice tea revealed that the formation of a Maillard reaction product in the course of heating the rice added a unique flavor, which led to increase preference for the color, flavor, and taste, and therefore, the overall preference.

• Applied Microscopy
• /
• v.37 no.1
• /
• pp.11-21
• /
• 2007

Saengshik which is food not to apply heat is expected to have good effect on the body because metabolic enzymes are preserved in it. In fact, despite of enlargement of saengshik market, the researches on the effect of saengshik are insufficient. So, the aim of this study was to investigate the protective effect of saengshik against $CCl_4-inducing$ hepatotoxicity in ICR mice. As the result of serum biochemical parameters, AST (SGOT) and ALT (SGPT) were significantly decreased at the experimental group treated with saengshik and $CCl_4$ as compared with experimental group 1 treated with $CCl_4$ only (p<0.01). ALP was significantly higher at experimental group 2 compared with control and experimental group 1 (p<0.01). In histological study, experimental group 1 treated with $CCl_4$ only showed severe necrosis all over the liver at the gross observation, and showed severe perivenular necrosis and individual hepatocytic degeneration. However experimental group 2 was not nearly different from control group in appearance and showed mild perivenular necrosis and dominant sever neutrophil infiltration surrounding central veins. The result of this study showed the protective effect against $CCl_4-inducing$ hepatotoxicity and suggest the possibility of the functional health food. However, further studies about the effect of saengshik may be needed.