• Food Science of Animal Resources
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• v.27 no.2
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• pp.163-170
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• 2007

The effects of olive oil on the quality characteristics of pressed ham were investigated. Five different treatments were carried out varying the amount of olive oil added to pressed ham. for the control, 10% back fat among the total ham components was added without any olive oil. For the first treatment, 5% olive oil within the lard component was added into the pressed ham. The 2nd, 3rd and 4th treatments included 10%, 15% and 20% olive oil, respectively. Manufactured pressed hams containing olive oil were vacuum packaged and then stored for 28 days at $4^{\circ}C$. The crude protein and crude fat were not significantly different between the control and olive oil treated hams. The moisture and crude ash contents of olive oil treated hams was significantly lower than that of the control(p<0.05). There was no significant difference in pH between the control and olive oil treated hams. The pH increased during the first 7 days of storage and then decreased somewhat for the remainder of the 28 day storage period for all treatments. The meat color $b^*$ value of olive oil treated hams was higher than that of the control, whereas the meat color $a^*$ value decreased with the inclusion of olive oil. Neither value changed during the period of storage. There was no significant difference in texture between the control and olive oil treated hams throughout the storage period. In summary, pressed ham manufactured with added olive oil showed no change in physico-chemical properties and texture characteristics. Thus, it may be assumed that high quality pressed ham can be manufactured with increased monounsaturated fatty acid content.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.290-298
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• 2007

The effect of packaging methods on the quality of stick type restructured jerky was investigated in terms of pH, water activity $(A_w)$, TBA (thiobarbituric acid) value, total bacterial counts, and sensory evaluation during storage at room temperature $(25^{\circ}C)$ for 90 days. The jerky was subjected to plastic or vacuum packaging at $(25^{\circ}C)$. The pH decreased slightly as storage time increased (p<0.05), but there were no significant differences between the packaging methods. The water activity of jerky in plastic packaging decreased as storage time increased (p<0.05), however jerky in vacuum packaging showed no significant change. Vacuum packaging resulted in a higher water activity value than plastic packaging. The TBA and hardness values decreased as storage time increased (p<0.05), and there were significant differences between packaging methods during the storage period (p<0.05). The total bacterial counts in vacuum packaged jerky were lower than jerky in plastic packaging. The sensory evaluation of each treatment decreased slightly as storage time increased (p<0.05), however there was no significant difference between packaging methods. Based on our findings, we conclude that vacuum packaging provides more effective storage than common packaging of jerky.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.528-533
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• 2008

Staphylococcus aureus is a pathogene of major concern in livestock products. This study was conducted to test imported and domestic meat sold by retail stores for the presence S. aureus. In addition, the antibiotic susceptibility of any S. aureus found was also evaluated. The overall isolation rate of S. aureus was 20.2% (13.9% in pork and 33.8% in beef) in retail meats. The percentage of imported meats found to contain S. aureus (33.3% in pork and 40.4% in beef) was higher than that of domestic meat (13.0% in pork and 14.7% in beef). In addition, the detection rate of S. aureus was higher in raw material meat than in ready to cook packaged meat. When the antibiotic susceptibility of S. aureus isolated from the meat products was evaluated, ampicillin was found to be the highest (76.5%), followed by penicillin (75.3%), tetracycline (27.1%) and erythromycin (21.2%). Penicillin and tetracycline resistant were detected in 55.6% and 13.3% of the beef isolates, respectively, and 97.5% and 42.5% of the pork isolates, respectively. The tetracycline and erythromycin resistant plasmids of the isolated strain were transferred into S. aureus DPRMM2429 by the filter mating method and the frequencies of transfer was found to be $1.1{\times}10^{-5}{\sim}1.9{\times}10^{-9}$ and $1.2{\times}10^{-5}{\sim}4.0{\times}10^{-8}$ respectively.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.864-871
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• 2014

Seed viability is affected by storage conditions and rapid loss of viability in storage is the major cause for low germination. This study was carried out to examine the effect of packaging materials and storage temperature on seed germination rate over 10 years in two species (Capsicum annuum L. and Brassica rapa L. ssp. pekinensis) and determine effective storage conditions for maintaining seed viability. Seeds were packaged in aluminum poly pouches under vacuum, polyethylene bottles, and paper bags containing silica gel and stored under one of two controlled conditions ($15^{\circ}C$, RH 40% or $5^{\circ}C$, RH 30%) or at ambient condition. Seed germination was recorded at 6-month intervals for 10 years. The seeds of both species showed no decline in viability until 6.5 years at 15 or $5^{\circ}C$, irrespective of packaging materials. However, under ambient conditions, the seeds of chili pepper and Chinese cabbage in paper bags lost viability after 4 and 5 years, respectively. By contrast, seeds of both species in vacuum-aluminum poly pouches exhibited a 99% germination rate after 6 years under ambient conditions. Pepper seeds in the vacuum-aluminum poly pouches maintained a 93% germination rate after 10 years in ambient conditions. These results indicated that a special seed storage facility for maintaining viability of chili pepper and Chinese cabbage seed might not be essential and seed testing would not be necessary for 10 years, if chili pepper and Chinese cabbage seeds were packed in ambient/vacuum-aluminum poly pouches or $5^{\circ}C$/vacuum-aluminum poly pouches.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.834-844
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• 2014

Postharvest browning of mushroom (Agaricus bisporus) reduces the shelf life of harvested mushrooms. Here, mushrooms were dipped in various solutions (distilled water; DW, 0.25% rice bran extract; RB, 0.1% ascorbic acid; AA, RB + AA) for 3 min. After air-drying at room temperature, the dipped mushrooms were packaged in a polypropylene (PP) films and stored at 4 or $15^{\circ}C$. The quality changes of mushrooms were measured in terms of color, gas composition, firmness, and sensory evaluation during storage. Rice bran extract was measured for total polyphenol content, total flavonoid content, DPPH, ABTS radical scavenging, chelating activity and PPO inhibition activity. No difference in firmness were found in the mushroom samples regardless of dipping solution or storage temperature. At both 4 and $15^{\circ}C$ storage temperatures, RB + AA solution-dipped samples showed the highest L value and lowest delta E value. During the storage period, sensory evaluation showed that overall acceptability of mushrooms treated with RB and RB + AA solution was higher than that of the untreated mushrooms. Total polyphenol and flavonoid contents of 0.25% rice bran extract were $36.42mg\;GAE{\cdot}g^{-1}$ and $4.85mg\;QE{\cdot}g^{-1}$, respectively. The DPPH and ABTS radical scavenging activity of 0.1% ascorbic acid was higher than that of 0.25% rice bran extract. The highest copper ($Cu^{2+}$) chelating activity was found in the 0.25% rice bran extract. The PPO inhibition activity of 0.1% ascorbic acid was higher than that of 0.25% rice bran extract. Our results suggest that 0.25% rice bran extract with 0.1% ascorbic acid is effective anti-browning agent for maintaining quality of Agaricus bisporus during storage.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.498-502
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• 2007

A total of 5 female elk deer($220kg{\pm}10kg$) were included in a study on the changes in physico-chemical properties of deer meat during storage at $-4^{\circ}C\;and\;-2^{\circ}C$. The deers were exposed to normal pre-slaughter handling and put under anesthesia before slaughtered. The loin and leg cuts were deboned from the carcass after 24hrs slaughter. The samples weighing approximately 300g were packaged using wrap packaging and stored for 1, 2, 3, 4, 5 and 6 months at $-30^{\circ}C\;and\;-60^{\circ}C$. During the freezing period, the changes of moisture maintenance was slower for the meats kept at $-60^{\circ}C$ than that at $-30^{\circ}C$. The meat softness represented higher value after freezing, and it tended to be decreased with the passage of storage time. Comparing the values between freezing temperature, the value at $-30^{\circ}C$ was higher than at $-60^{\circ}C$. All meats frozen at $-30^{\circ}C\;and\;-60^{\circ}C$ were edible after storage for 6 months. Loin was inedible, and leg was edible after freezing storage for 6 months. The pH values of the meats were increased during freezing period, even though pH value of the meats stored for 6 months was less than 5.70. Luminosity of loin was significantly increased with the passage of storage time, although loin stored at $-60^{\circ}C$ was darker, and leg stored at $-30^{\circ}C$ was darker. The index of red color was rapidly decreased for loin stored at $-30^{\circ}C$, and for leg stored at $-60^{\circ}C$, respectively. There were no changes in the index of yellow color for loin stored at $-60^{\circ}C$, and the index for leg was increased with regardless of the freezing storage temperature after 6 months.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.1-8
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• 2006

To investigate the effect of ${\beta}$-hydroxyacyl CoA-dehydrogenase(HADH) activity increased by freezed and thaw process on myoglobin(Mb) oxidation without lipid oxidation during, pork loins were collected at postmortem 24 hts and sliced to steaks (3 cm thickness). Samples were packaged in a polyethylene bag and subjected to flesh group (control), one cycle fieezed and thaw group (treatment 1) and two cycles freezed and thaw group (treatment 2), respectively. Samples were measure meat color (CIE $L^*,\;a^*,\;b^*$), the contents(%) of MetMb, thiobarbituric acid reactive substance (TBARS) value and HADH(${\beta}$-hydroxyacyl CoA-dehydrogenase) activity at 0, 3, and 7 days of storage at $4^{\circ}C$. Both treatments showed significantly (p<0.05) lower $L^*$ and higher $L^*$ value compared to those of control at 7 days. On the contrary, MetMb contents(%) of treatments were significantly (p<0.05) higher than those of control during cold storage. However there were no significant (p> 0.05) differences in TBARS values between control and treatments during 7 days. There were significant (p<0.05) differences in HADH activity between control and treatments at 3 days of cold storage. Both treatments showed higher HADH activity compared to those of control. These results suggested that the freezed and thaw process could accelerate meat color deterioration, i.e. increased MetMb percentage without lipid oxidation in pork loin during cold storage. This also implied that autoxidation of Mb in freezed and thaw pork loin was influenced by enzyme-catalysed reactions in the tissue that would lead to decreased OxyMb.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.175-188
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• 2005

This study investigated the effects of silkworm droppings (SWD) added diet feeding on quality characteristics of pork loin meat Pigs were divided into 7 treatment groups (10 pigs/group) and subjected to one of seven treatment diets $(0,\;1\%,\;2\%\;and\; 3\%\;SWD\;for\;4 weeks,\;1\%\;2\%\;3\%$ SWD for 8 weeks, SWD diets; total fed diets) before slaughter. Pork loin were collected from the animals (110kg body weight) slaughtered at a commercial slaughterhouse. Pork loin meat were packaged aerobically and then stored at $4^{\circ}C$ for 2, 5, 8, or 12 days. Samples were analyzed for general composition, texture characteristics and physico-chemical properties. pH value was not significantly different between the control and SWD treatment groups. pH of control and SWD treatment groups were increased as the storage period passed General composition, cooking loss and texture was not significantly different between the control and SWD treatment groups. WHC of SWD treatment group was higher than that of control group. WHC of control and SWD treatment groups were significantly decreased as the storage period passed (p<0.05). Meat and fat color (CIE $L^{\ast}$, $a^{\ast}$, $b^{\ast}$) were no significant differences between the control and SWD treatment groups. $L^{\ast}$ and $b^{\ast}$ value of meat color were decreased as the storage period passed There was a not significantly difference in shear force value among control and SWD treatment groups. Shear force value was decreased significantly during storage in all treatment groups. In all results, dietary SWD-supplementation was not affected in general components, texture characteristics and physico-chemical properties. It is suggested that dietary SWD-supplementation could produce of high quality pork.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.80-86
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• 2007

This experiment was conducted to investigate the changes of pork meat quality characteristics exposed to ozone gas for 5, 10, and 15 min and then vacuum packaged during storage for 0, 5, 10, 15, and 20 day at $4^{\circ}C$. The ozone gas exposed groups of pork loin cuts (OZM) had slightly higher pH value compared to the control at day 0 and 5 (p<0.01). The 15 min exposure of ozone gas groups showed significantly (p<0.01) higher TBARS value than that of control at the day 15 and 20. However, there was no significant difference in all groups at day 0,5, and 10. The CIE $L^*$ and $b^*$ values of OZM showed no significant difference between control and ozone gas treated groups during storage. The loin cut color of ozone gas exposure for 15 min had significantly lower CIE $a^*$ values than the other groups at day 0,5, and 15 (p<0.01). The aerobic plate count and coliform bacteria count of pork loin cuts exposed ozone gas significantly (p<0.01) was reduced at day 0 by about $0.45-1.04\;log_{10}CFU/g$ and $0.26-0.30\;log_{10}CFU/g$, respectively. As ozone gas exposure time extended, the aerobic plate count and coliform bacteria count of OZM were increased at day 0, 5, and 10 (p<0.01). However, there were no significant differences observed among groups at day 20 in the counts of aerobic and coliform bacteria. In conclusion, the meat cuts exposed to ozone gas for 5 and 10 min before packing may be a reasonable packing method regarding the effects of ozone level on meat oxidation, color change and microbial reduction.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.8-15
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• 2007

Conjugated linoleic acid (CLA) was chemically synthesized using the alkaline isomerization method of com oil. CLA-TG was synthesized by reaction with sodium methoxide. Five different treatments were devised based on differences in the amount of CLA-TG added into the pressed han. for controls, 10% of pork back fat among the total component was only added without any CLA-TG. For the first treatment, 5% of CLA-TG among the lard component added into the press ham was replaced. For the 2nd, 3rd and 4th treatments, 10%, 15% and 20% of CLA-TG was respectively replaced. Pressed ham manufactured using CLA-TG was vacuum packaged and then stored for 1, 7, 14, 21 and 28 days at $4^{\circ}C$. Samples were analyzed for chemical composition, physico-chemical properties (pH, color), and texture characteristics. Typical chemical composition characteristics (moisture, crude protein, crude fat) were not significantly different between controls and CLA-TG treatment groups. Crude fat content of CLA-TG treatment groups was significantly lower than that of controls (p<0.05). pH values of controls was higher than that of CLA-TG treatment groups. The pH of control and CLA-TG treatment groups increased significantly as the storage period increased (p<0.05). Meat color (CIE $L^*,\;b^*$) of CLA-TG treatment groups was higher than that of controls. $a^*$ values were decreased by replacement of CLA-TG, but appeared to be unaffected by storage length. There was no significant difference in texture between controls and CLA-TG treatment groups. Based on these findings, we conclude that the physico-chemical properties and texture characteristics of manufactured pressed ham were not affected by CLA-TG addition. Also, our results indicate that high-quality pressed ham can be manufactured with CLA accumulation.