• Food Science and Preservation
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• v.24 no.2
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• pp.168-180
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• 2017

This study was performed to determine the rapid thawing method for reducing the thawing time of frozen pork loins and to examine the effects of supercooling on the microbiological, physicochemical, and sensory qualities of fresh and frozen-thawed pork during storage at -1.5, 4, and $15^{\circ}C$. Forced-air thawing at $4^{\circ}C$ was the most time-consuming process, whereas radio frequency thawing time was the shortest by dielectric heating. The supercooling storage temperature was chosen to be $-1.5^{\circ}C$ because microstructural damages were not observed in the pork sample after cooling at $-1.5^{\circ}C$ for 24 h. Fresh or frozen-thawed pork loins stored at $-1.5^{\circ}C$ had lower drip loss and total volatile base nitrogen, thiobarbituric acid-reactive substance, and Hunter b* levels than loins stored at 4 and $15^{\circ}C$. In addition, the least degree of increase in preexisting microorganisms counts of the fresh or frozen-thawed pork loin samples was obtained during supercooled storage at $-1.5^{\circ}C$. Sensory quality results of fresh and frozen-thawed pork loin samples stored at $-1.5^{\circ}C$ showed higher scores than the samples stored at 4 and $15^{\circ}C$. These data indicate that supercooling at $-1.5^{\circ}C$ in the meat processing industry would be effective for maintaining the quality of pork meats without ice crystal nucleation and formation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1258-1264
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• 2005

We determined the effect of chlorine dioxide ($ClO_{2}$) treatment on microbial growth and quality of saury. Saury samples were treated with aqueous $ClO_{2}$ at 3, 10, and 50 ppm. After the treatment, saury samples were stored at -20$^{\circ}C$ and 4$ ^{\circ}C$, respectively. Saury samples treated with $ClO_{2}$ had significantly lower total bacterial counts during storage. In particular, treatment of 50 rpm $ClO_{2}$ decreased total bacterial count most significantly among the $ClO_{2}$ treated saury samples. After 4 days, populations of total bacteria for the control reached 6.43 log CFU/g, while the sample treated with 50 ppm of $ClO_{2}$ had 5.47 log CFU/g at the 9th day of storage. $ClO_{2}$ treatment also delayed increase in the population of psychrotrophic bacteria on saury. The pH of saury samples decreased with increase of $ClO_{2}$ concentration. Volatile basic nitrogen (VBN) and thiobarbituric acid reactive substance (TBARS ) values of saury samples increased during storage, regardless of $ClO_{2}$ concentration. Sen-sory evaluation of saury samples showed that treatment with $ClO_{2}$ could improve the quality of saury. These results indicate that $ClO_{2}$ treatment could be useful in improving microbial safety and quality of saury.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.6
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• pp.851-859
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• 2012

This study was conducted to investigate the effects of addition of lotus (Nelumbo nucifera) leaf and root extracts on the quality and sensory characteristics of ground pork meat. Four types of ground pork were evaluated: 5% ice water added (T0), 5% lotus leaf extract added (T1), 2.5% lotus leaf extract and 2.5% root extract added (T2), and 5% lotus root extract added (T3). There were no significant differences in moisture, protein, fat, ash, cooking yield, moisture retention, water holding capacity, reduction in diameter, a-value (redness), b-value (yellowness), VBN content (volatile basic nitrogen), hardness, springiness, cohesiveness or chewiness. The fat retention was highest in T0 (p<0.05). The L-values (lightness) of T2 and T3 were higher than those of T0 and T1 (p<0.05). The pH was lowest in T1 (p<0.05). The TBARS (2-thiobarbituric acid reactive substances) values of T0, T1, T2, and T3 were 0.47, 0.17, 0.21, and 0.32 mgMA/kg, respectively, with that of T1 being significantly lower than those of the other samples (p<0.05). The contents of free amino acids related to sweet taste was 642.5 ppm for T1, which was highest among the samples (p<0.05). The flavor was highest in T1 (p<0.05). These results suggest that lotus leaf extracts improved the lipid oxidation and flavor of ground pork meat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.231-237
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• 1984

Changes in available lysine and water soluble proteins were checked to obtain the desirable condition of processing for boiled Neverita didyma under the various autoclaving temperatures and times. It was also carried out to assess the affect of heat treatments upon the solubility of coagulable substances in boiled products. In order to evaluate the nutritional quality of processed Neverita didyma under the highest available lysine retention and without bacteria, it was studied the value of pepsin-pancreatin digest residue index in comparison with unprocessed (raw) material. The crude protein content of raw material was higher than that of the other mollusks, while the content of crude fat was showing lower value. It was noticed that the higher contents of coagulable substances and water soluble proteins in processed Neverita didyma were obtained under the conditions, retort temperature at $120^{\circ}C$ above, and 40-60 min. sterilization. After the pannel test, the coagulable substances were not found below the level of $0.40{\pm}0.03$ gram nitrogen/ml of juice. The remarkable retention of available lysine (FDNB-reactive lysine) was resulted in the conditions of autoclaving at $115^{\circ}C$ for 40 minutes in boiled Neverita didyma products, and that processing condition was coincide with the condition of commercial sterilization for boiled top shell. It was revealed that the boiled meat of Neverita didyma showed the higher PPDRI(65.85) than that of raw material (63.16).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.774-783
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• 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 Animal Science and Technology
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• v.46 no.5
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• pp.859-870
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• 2004

This study was conducted to investigate physico-chemical changes of pork prepared by Korean traditional 3 types seasoning such as soybean sauce(Tl); garlic sauce(T2); red pepper sauce(T3). The seasoned samples were aged at 0 ${\pm}$ $1^{\circ}C$ for 30 days. The results obtained were as follows; Salinity(%) and saccharinity(%) of sauce were significantly decreased(P<0.05) among the all treatments during aging periods, whereas fermented meats were significantly increased(P<0.05). pH of sauce and fermented meat were tended to increased as aging period. Water-Holding Capacity(WHC) and shear force of fermented meat increased(P<0.05) among the all treatments at 20 days of storage, and decreased after that period. In color, $L^* and b^* value of T3 were lower, while a^*$ value was higher than other treatments during aging period. Volatile Basic Nitrogen(YBN) value of all treatments were increased(P<0.05) after 20 days of storage. YBN value of T3 was significantly higher(P<0.05) compared with other treatments. Thiobarbituric Acid Reactive Substances(TBARS) was rapidly increased until 10 days of storage and somewhat decreased up to 20 days after 10 days in all treatments, it was re-increased after 20th days. T3 showed the highest TBARS among the all treatment groups. Total bacterial and Lactobacilli spp. were significantly increased(P<0.05) in all treatments at 10 days of storage and decreased after that period, however it tended to increased at 30 days of storage. In sensory evaluation, overall acceptability in all treatments were increased after 20 days of storage compared to initial storage and it score was similar thereafter.

• Childhood Kidney Diseases
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• v.17 no.2
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• pp.110-116
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• 2013

Purpose: The $^{99m}Tc$-Dimercaptosuccinic acid (DMSA) renal scan is used primarily for the diagnosis of renal scarring and acute pyelonephritis in children with urinary tract infections (UTI). This study aimed to evaluate clinical differences based on the positive or negative results of DMSA scans and kidney ultrasonography (US) in pediatric UTI. Method: We retrospectively reviewed 142 pediatric patients with UTI who were admitted to Myongji Hospital from January 2004 to December 2012. We performed a comparative analysis of clinical parameters such as age, sex, white blood cell (WBC) count, neutrophil count, blood urea nitrogen (BUN) level, creatinine (Cr) level, C-reactive protein (CRP) level, and durations of hospitalization and fever, grouped by the results of the DMSA scans and kidney US. Results: The mean age of the patients was $33.8{\pm}48.3$ months, and 78 (55%) were male. Fifty-two patients had abnormal DMSA findings, and 71 patients had abormal kidney US findings (test positive groups). In the DMSA scan positive group, there were significant differences in age, WBC counts, neutrophil counts, CRP level, BUN level, Cr level, hospitalization duration, number of abnormal findings on kidney US, and incidence of vesicoureteral reflux (VUR) compared with the scan negative group. The kidney US positive group had significant differences in age, neutrophil count, CRP level, BUN level, Cr level, hospitalization duration, number of abnormal findings on the DMSA scans, and more frequent VUR compared with the US negative group. Conclusion: Our data suggest that there were no major differences in clinical parameters based on the results of the DMSA scans compared with kidney US in pediatric UTI. However, as kidney US and DMSA scan were performed to predict VUR, the sensitivity and negative predictive value was increased.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.243-251
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• 2010

This study was conducted to investigate the effects of the addition of cordyceps ochraceostromat, conjugated linoleic acid (CLA) and silkworm cocoon on the quality and storage characteristics of pork sausage manufactured by MDCM (mechanically deboned chicken meat) recovered protein. The samples were divided into 5 groups (sausage made from pork ham; control, 40% of MDCM recovered protein to replace pork ham; T1, 40% of MDCM recovered protein to replace pork ham with 0.1% cordyceps ochraceostromat; T2, 40% of MDCM recovered protein to replace pork ham with 0.1% CLA; T3, and 40% of MDCM recovered protein to replace pork ham with 0.1% silkworm cocoon; T4). The control sample had a higher moisture and protein contents and lower fat content than the other samples during 4 weeks of storage at $4^{\circ}C$ The treatment samples had lower lightness and higher redness values than the control (p<0.05). Hardness, cohesiveness, gumminess and chewiness were significantly lower in the treatment samples than the control (p<0.05). All sausage samples showed a significant increase in thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen, and total plate counts during the storage time (p<0.05). In addition, the MDCM treatment samples had higher TBARS values than the control, but the VBN value of the treatment samples was lower than the control after the 4 weeks storage period.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.277-285
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• 2010

The objective of this study was to manufacture spent layer chicken meat products by natural freeze-drying. The spent layers of chickens that were slaughtered at 80 wk were obtained from a local slaughter house and separated into two halves of carcasses. The samples were divided into the following groups: 1) control (non-curing), 2) curing, and 3) curing with 2% trehalose before drying. The cured meats were placed at $2^{\circ}C$ for 7 d and then transferred to a natural drying spot located in Injae City, Gangwondo, Korea. The experiment was conducted from January to March in 2008. The average temperature, RH, and wind speed were $-1.5^{\circ}C$, 63%, and 1.8 m/sec, respectively. The cured treatments showed higher pH, lower Aw and lower shear force value compared with the control. Based on the results of TBARS (2-thiobarbituric acid reactive substances) level and volatile basic nitrogen value, lipid oxidation and protein deterioration were inhibited in curing treatments during drying. Trehalose acted as a humectant because it maintained a lower water activity despite the relatively higher moisture content during drying. The polyunsaturated fatty acids content and sensory attributes were higher in cured treatments than in the control during drying. Most of the bacterial counts in the treated groups were lower by 2 Log CFU/g after 1 mon of drying, and Salmonella spp. and Listeria spp. were not found in any treatment. There was also no microbial safety problem associated with dried meat products. Based on the results of this experiment, dried meat products could be manufactured from precured spent layer chickens by natural freeze-drying during winter.

• Food Science and Preservation
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• v.25 no.1
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• pp.145-154
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• 2018

The purpose of this study was to investigate the ability of natural antioxidants as stabilizers for meat by-products to prevent lipid oxidation. The white internal organs were evaluated using different treatments: no antioxidant (control), ascorbic acid (T1), Artemisiacapillaris Thunb. (T2), Opuntia (T3), Schisandra chinensis (T4), and Saururuschinensis (Lour.) Baill (T5). Antioxidant activities were analyzed by measuring DPPH contents, superoxide anion radical levels, nitrate scavenging activities, and total polyphenol contents. T1 and T2 showed higher antioxidant activities and total polyphenol contents (p<0.05). Additionally, changes in physicochemical properties (pH, color, volatile basic nitrogen [VBN], and thiobarbituric acid reactive substances [TBARS]) and microbiological aspects in white internal organs processed with antioxidants were investigated. As storage time increased, the CIE $a^*$ and $b^*$ values of the white internal organs processed with natural antioxidants were decreased (p<0.05), and CIE $L^*$ values were low, particularly for the T3 sample relative to that in the control. Moreover, the pH, VBN, and TBARS values of samples T2-T5 were increased after 7 days of storage, but showed low values compared with those of the control (p<0.05). Moreover, compared with the control group, the treatments showed antimicrobial effects. Our results indicated that these natural antioxidants could be used as lipid oxidation stabilizers of meat by-products during storage and that Artemisiacapillaris Thunb. and Opuntia may have applications as natural antioxidants in the meat by-product industry.