• 한국식품조리과학회지
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• 제23권6호
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• pp.940-946
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• 2007

In this study, raw whole garlic and peeled garlic were pickled in brine, to test for changes in flavor compounds by aging period. Changes in pH, acidity and hardness were measured, and a sensory evaluation performed. The pH of the peeled garlic Jangachi in brine decreased as the aging period increased. The acidity increased as pH decreased, and the hardness tended to decrease as the aging time increased. For the peeled garlic Jangachi in brine, 3,3-thiobis-l-propene, allyl methyl trisulfide, diallyl trisulfide, and dimethyl trisulfide increased as aging proceeded, but allyl methyl disulfide and diallyl disulfide tended to decrease. In the sensory evaluation, hardness decreased as the aging time increased. Therefore, the above flavor compounds are considered to be major components of the characterized flavor of pickled garlic. When the overall quality was compared between the whole garlic Jangachi and peeled garlic Jangachi in brine after 60 days, the peeled garlic Jangachi was deemed superior.

• 한국식품영양학회지
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• 제24권4호
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• pp.761-769
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• 2011

The objective of this study was to investigate the physicochemical properties of Korean traditional soy sauces made with soybeans sown in different producing regions(Hadong, Paju) and in different seeding periods(late-May, mid-June, late-June). The total acidity, salt content, chromaticity, browning, amino nitrogen content and the reducing sugar content of the soy sauce samples were compared. It was found that the total acidity level and the amino nitrogen contents were significantly lower in the soy sauce made with mid-June soybeans, and that these properties increased as the sauce aged. Salt content increased with the aging period regardless of the region of production. The reducing sugar content of Paju soy sauce was the highest in late -June, and for the Hadong region, highest in late-May. The sauce made with Hadong soy beans showed an increase in reducing sugar content positively correlated with the aging period. Reducing sugar content in the samples of Paju soy sauce decreased up to 60 days of aging, but increased after this point. In Paju soy sauce, the brightness(L value) was significantly higher in mid-June, and the Hadong variant it was higher in late -May. The yellowness(b value) at the beginning of the aging process was high in late -June for Hadong soy sauce, but overall it was higher in the mid-June period. The more matured soy sauce samples were darker and showed both higher a and b values. The browning was the lowest in the mid -June regardless of the regions and it increased with the aging period regardless of the production regions. The salt, amino nitrogen contents, browning and yellowness showed significant correlations among the samples. In conclusion, the seeding period of soy beans may affect the characteristics of produced soy sauce alongside the aging conditions.

• Elastomers and Composites
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• 제1권1호
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• pp.56-62
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• 1966

The aging characteristics of vulcanized rubber products manufactured in Korean industries have been studied, especially in terms of relationship between aging temperature and time, and also the comparison of results between Geer's oven testing and tube testing was made. It was assessed from changes in tensile properties resulting from conditioning at elevated temperatures for specified period of time. Even though the recipe of each sample is different, the results, as would be expected, has shown that at lower aging temperature the change of tensile strength indicate moderately and at the elovated severely as shown in Figure 9. Consequently, in spite of that the results from conditioning at various temperatures for certain specified period of time must be equivalent to each other, it shows inignorable tolerance. The results of Geer's oven test and tube test have shown slightly different value. It seemed to be caused by the result of migration phenomena on aging in Geer's oven.

• 동아시아식생활학회지
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• 제21권4호
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• pp.545-552
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• 2011

Fernbraken is a popular and well-known wild grass, but the physiochemical properties of Korean Traditional pickling (Jangachi) during aging have been little reported. Therefore, this study was carried out to investigate the physiochemical properties of Fernbraken Jangachi treated with a soybean sauce mixture for 6 weeks (1st pretreatment) as well as fermented with soybean paste, red hot pepper paste and soybean sauce for 7 weeks. Total polyphenol contents, acidity, salinity, sweetness (Brix), and ${\alpha}$-tocopherol of Fernbraken Jangachi all increased with aging period. On the other hand, pH and total acidity of Fernbraken Jangachi did not change much. Among the three kinds of Jangachies, Jangachi fermented with soybean sauce showed 2 fold higher salinity and total acidity levels compared to the others. Therefore, the physiochemical properties of Fernbraken Jangachi were dependent on the pickling properties, such as soybean paste, hot pepper paste or soybean sauce, and these properties maintained a certain level after 5~6 weeks of aging. Further, proper aging period for Fernbraken Jangachi was suggested as 10 weeks.

• 한국축산식품학회지
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• 제25권2호
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• pp.127-133
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• 2005

진공 포장한 우육을 $0\pm1^{\circ}C$에서 8주간 냉장하면서 숙성 효과를 조사하였다. 우육의 경도, 저작성 및 전단력은 냉장 5주까지 저하되어 연화 효과가 있었으나 6주 후에는 그 효과가 없었다. 근원섬유단백질의 추출성, Mg-ATPase활성 및 근원섬유 소편화도는 6주까지 높아졌으나 그 후 8주까지 변화하지 않았다. 우육의 색도는 냉장 8주까지 양호하였다. 우육의 기호도는 5주까지 향상되었으나 6주 이후에는 오히려 저하되었다. 진공포장하여 냉장한 우육의 숙성 효과는 5주까지 기대할 수 있었다.

• 한국축산식품학회지
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• 제31권6호
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• pp.799-806
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• 2011

This study was conducted to evaluate the effect of the aging period prior to freezing on the meat quality of Hanwoo longissimus dorsi (LD) muscle. Three different combinations of aging and freezing periods (0/90, 20/70, and 40/50) were examined using LD muscle at 24 h postmortem under an identical storage time of 90 d. The pH and lightness slightly increased with increasing aging period. However, there were no significant (p>0.05) differences in redness and yellowness. The solitary freezing treatment (0/90) had the significantly (p<0.05) lowest moisture content. The un-aged treatment had a significantly (p<0.05) higher total loss than the aged treatments due to an increase in thaw drip loss. The aging significantly improved the myofibrillar fragmentation index and shear force of Hanwoo LD muscle (p<0.05). In addition, the aged treatments produced a higher flavor, tenderness, juiciness, and overall acceptability relative to un-aged treatment. However, there was no significant (p>0.05) difference in shear force and sensorial properties between 20 and 40 d aging prior to freezing. Therefore, 20 d aging prior to freezing may be a sufficiently effective strategy to improve the tenderness and sensorial properties of Hanwoo LD muscle.

• 한국축산식품학회지
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• 제32권4호
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• pp.428-433
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• 2012

The objective of this study was to identify appropriate aging conditions, changes in nucleotide-related compounds, chemical changes, and a sensory evaluation of duck meat during aging at $0^{\circ}C$ for 7 d. Twenty one 45-day-old Pekin white ducks samples were separated into breast and leg meat. ATP was not detected for almost the entire aging period because ATP was depleted immediately after slaughter. Inosine monophosphate (IMP) was highest on day 1 ($26.69{\mu}mol/g$), and then it rapidly decreased to $7.11{\mu}mol/g$ on day 7. However, this level was not different between breast and leg meat. Hypoxanthine (Hx) content of breast meat was $14.88{\mu}mol/g$, whereas that of leg meat was $16.41{\mu}mol/g$. Inosine content of breast meat was double than that of leg meat. The pH values of breast and leg meat were 5.90-6.05 and 6.23-6.73, respectively, during the aging period. Volatile basic nitrogen content of breast and leg meat increased during aging. Breast meat had good sensory evaluation scores for flavor (7.4), juiciness (6.8), tenderness (7.2), and overall acceptance (7.4) on day 3. Similar to breast meat, leg meat also had good sensory evaluation scores. Therefore, it is concluded that the appropriate aging period is 3 d for duck breast meat and 1 day for leg meat at $0^{\circ}C$.

• 대한기계학회논문집A
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• 제28권12호
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• pp.1968-1973
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• 2004

Structural degradations are often experienced on the components of nuclear power plants in reactor pressure vessels (RPV) and steam generators (SG) when these components are exposed to high temperature and high pressure for a long period of time. Such conditions result in the change of microstructures and of mechanical properties of materials, which requires an evaluation of the safeguards related to structural integrity. In a primary reactor cooling system (RCS), a dissimilar weld zone exists between cast stainless steel (CF8M) in a pipe and low-alloy steel (SA508 cl.3) in a nozzle. Thermal aging is observed in CF8M as the RCS is exposed for a long period of time under the operating temperature between 290 and 33$0^{\circ}C$. Under the same conditions, it is well known that degradation is not observed in low alloy steel. An investigation of the effect of thermal aging on the various mechanical properties of the dissimilar weld zone is required. The purpose of the present investigation is to find the effect of thermal aging on the dissimilar weld zone. The specimens are prepared by an artificially accelerated aging technique maintained for various times at 43$0^{\circ}C$, respectively. Then, The various mechanical test for the dissimilar welds are performed.

• 한국축산식품학회지
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• 제36권2호
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• pp.215-222
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• 2016

The combined effects of irradiation and aging temperature on the microbial and chemical quality of beef loin were investigated. The samples were vacuum-packaged, irradiated at 0 or 2 kGy using electron-beam (EB), and stored for 10 d at different aging temperatures (2, 14, or 25℃). The microbial growth, shear values, meat color, and nucleotide-related flavor compounds of the samples were analyzed. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and Escherhia coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose. Irradiation reduced the total aerobic bacteria (TAB) over the storage, but higher aging temperature increased the TBA. Thus TAB increased sharply in non-irradiated and high temperature-aged (14, 25℃) beef samples after 5 d. With increasing aging temperature and aging time, shear force values decreased. Lipid oxidation could be reduced by short aging time at low aging temperature. The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the aging period. As aging period and temperature increased, IMP decreased and hypoxanthine increased. Considering microbial and physicochemical properties, irradiation can be used for raw beef to be aged at relatively high temperature to shorten aging time and cost.

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.149-159
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• 2021

This study examined the effects of different wet-aging times on the physicochemical characteristics and microbial profile of longissimus lumborum (LL) and biceps femoris (BF) muscles from Korean native black goat (KNBG) meat. The water holding capacity (WHC), pH, cooking loss, shear force, meat color, free amino acid, total bacteria, and coliform count of KNGB meat were analyzed at 0, 5, 10, and 15 days of wet-aging at 4℃ under vacuum packaging. The results showed that different wet-aging times led to significant pH variations between the muscles throughout the aging period. The wet-aging time did not affect the WHC and cooking loss in meat from the LL muscle. In the BF muscle, however, meat wet-aged for five days had a significantly higher WHC and less cooking loss than meat aged for 0, 10, and 15 days. The meat from the LL muscle wet-aged for five days produced tenderer meat (low shear force value) than the unaged meat (p < 0.05). Moreover, the color was similar in the LL muscle regardless of the number of aging days. In the BF muscle, the redness (a*) was higher in the meat wet-aged for 15 days compared to that aged for 0, 5, and 10 days (p < 0.05). Regardless of the muscles, an increase in wet-aging time led to an increase in the total free amino acids contents in both muscles (p < 0.05). On the other hand, the tasty/bitter amino acid ratio was significantly higher for five days of wet-aged meat than 10 and 15 days of aging from the BF muscle. In addition, regardless of the muscles, the total bacteria and coliform counts were significantly lower for five days of wet-aged meat than 10 and 15 days of aging (p < 0.05). Therefore, chevon wet-aged for five days is an optimal aging period under vacuum packaging that fortifies meat quality with a minimal microbial negative defect.