• Food Science of Animal Resources
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• v.42 no.2
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• pp.332-340
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• 2022

The objective of this study was to determine the optimal cooking time by considering the cooking loss, shear force, and off-odor reduction of pork large intestines. Commercial pork large intestines were purchased, quartered perpendicularly, and cooked in boiling water for 40, 120, 180, and 240 min. Cooking loss of the samples increased after 240 min of cooking (10.92, p<0.05) while shear force value was lower at 240 min (4.45) compared to that at other cooking times (p<0.001). The amount of major volatile organic compounds showed a decreasing trend with increasing cooking time. In particular, the amount of methyl pentanoate (17,528.71) and methyl isobutyrate (812.51), compounds with a relatively low odor threshold, decreased significantly after 120 min of cooking and no change was observed thereafter (p<0.05). In addition, the amount of 2-pentanol (3,785.65) and 1-propanol (622.26), possibly produced by lipid oxidation, significantly decreased at the same cooking time (p<0.001). In the principal component analysis, only the 40 min cooking time was significantly different from other cooking time by high amounts of 1-propanol, 2-pentanol, and methyl isobutyrate. In conclusion, in the present study, the optimal cooking time for pork large intestines was 120 min in terms of off-odor reduction, cooking loss, and shear force.

• Journal of Animal Environmental Science
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• v.12 no.3
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• pp.133-140
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• 2006

The climate of stall significantly influences on animal production ability. High concentration of ammonia gas, $CO_2$ and lots of dust are found in modern densely raising stall system, as results, they provide a negative influence on animal and farmer health, and production ability. Therefore, it is necessary to keep clean the inside air of stall to increase the productivity. An air cleaner of wet type, consisting of a fan, a motor, rotating discs, a dust collector, a water bowl, an ozone generator etc, has been developed to clean the stall air. The work principle is that the inside air is sucked through the fan, and the rotating discs make water into fineness spray and blow into the stall. The rest water flows down to the dust collector. In the present study, we measured the dust, ammonia gas, odor, temperature and humidity in a swine stall that were installed two wet air cleaners with 700 fattening swine with On-mode and Off-mode of wet air cleaners. The dust measure was divided into 3 categories, TSP, $PM_{10}$, and $PM_{2.5}$. In summer, the TSP in on-mode were maximum $0.259mg/m^3$ and minimum $0.128mg/m^3$, and the average was $0.195mg/m^3$. These are comparable to the data from Off-mode stall that maximum $0.308mg/m^3$, minimum $0.139mg/m^3$, and average $0.277mg/m^3$. However, $PM_{10}$ and $PM_{2.5}$ showed any significant differences between the tests. The concentrations of ammonia gas in Off-mode stall were maximum 13.8 ppm and minimum 5.9 ppm, and the average was 8.47 ppm. However in On-mode stall the ammonia gas concentrations were maximum 10.5 ppm and minimum 5.5 ppm, and the average was 7.63 ppm. The concentration of ammonia gas in On-mode was 10% in average lower than off-mode stall. Odor was measured by olfactometer. In the Off-mode stall, the odor unit were maximum 420 $Ou/m^3$ and minimum $300\;OU/m^3$, and the average was $367\;OU/m^3$, but in the On-mode stall the odor unit were maximum $330\;OU/m^3$ and minimum $210\;OU/m^3$, and the average was $253\;OU/m^3$. Odor removal efficiency was about 31% in On-mode stall.

• Journal of Animal Environmental Science
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• v.14 no.2
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• pp.75-80
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• 2008

High concentration of $NH_3$, $CO_2$, and lots of dust are found in modern densely raising stall system, as results, they provide a negative influence on animal and lamer health, and production ability. Therefore, it is necessary to keep clean the inside of stall air to increase the productivity. A wet type air cleaner has been developed to clean the stall air. The work principle is that the inside air are sucked through the fan, and the rotating discs make a water into a fineness spray and blows into the stall. The spray can take the dust, $NH_3$, and odor from the stall inside air and give back to the circulating water, which can be refreshed in 2 hours interval. In the Present study, we measured the $NH_3$, dust, odor, temperature and humidity in a swine stall that were installed two wet air cleaners with 700 fattening swine with on-mode and off-mode of wet air cleaners. In fall, the concentrations of $NH_3$ in off-mode stall were maximum 24 ppm and minimum 16 prm, and the average was 18.2 ppm. However in on-mode stall the $NH_3$ concentrations were maximum 7ppm and minimum 1ppm, and the average was 2.7ppm. The concentration of $NH_3$ in on-mode was 74% lower than off-mode stall. Odor was measured by olfactometer. In the off-mode stall, the odor unit was 3,800 OU/$m^3$, but in the on-mode stall the odor unit was 2,100 OU/$m^3$ Odor removal efficiency was about 45% in on-mode stall. The dust measure was divided into 3 categories, $PM_{10}$, $PM_{2.5}$ and $PM_{1.0}$. Whereas the $PM_{10}$ showed no significant differences between the tests, $PM_{2.5}$ and $PM_{1.0}$ in the fine particle range reduced remarkably in the on-mode.

• Food Science and Preservation
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• v.10 no.1
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• pp.70-74
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• 2003

The distribution of mesophilic and thermophilic bacteria in milled rice was not different according to growing land and variety of rice. However, The number of these bacteria were abundant in milled rice of lower milling degree or longer storage period. The growth of thermophilic bacteria in cooked rice of electric rice cooker was rapidly increased during storage of lower temperature below 75 $^{\circ}C$. Thermophilic bacteria were not appeared just after cooking. After cooked rice was stored far 18∼24 hon thermophilic bacterial growth was rapidly increased by changing spore to vegetative cell. The positive relation between cell number of thermophilic bacteria and occurrence of off-odor was slightly observed. The number of thermophilic bacteria in upper cooked rice of oven and was higher than those in inner and lower cooked rice. Major volatile compound of milled rice cooked and stored in electric rice cooker was hexanal oriented from rice. After long storage, it was confirmed that furan was major volatile compound as off-odor.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.379-387
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• 1991

The effects of organic acids (acetic, citric and lactic acids) treatment on microbial spoilage of chilled beef were studied during aerobic storage at $4^{\circ}C$ for 11 days. The organic acids had definite effects on the delay of the development of off-odor and slime of chilled beef. When chilled beef slices were treated with 1, 2, 3 and 4% of organic acids, off-odor was developed 1, 2, 3 and 5 days later than control, respectively, regardless of the kinds of organic acid. The slime was produced two days after the day of off-odor development in $1{\sim}3%$ organic acid-treated chilled beef, but no slime was produced on chilled beef treated with 4% organic acid. The off-odor was detected organoleptically when pH and number of microorganisms of chilled beef were, $5.6{\sim}5.8\;and\;0.8{\times}10^7{\sim}1.8{\times}10^7\;cell/cm^2$, respectively, and slime was observed when pH and number of microorganisms of chilled beef were $5.9{\sim}6.2\;and\;2.0{\times}10^7{\sim}6.0{\times}10^7\;cell/cm^2$, respectively, in control and treated groups.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.57-64
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• 1988

The present study was conducted to characterize lipoxygenase isoenzymes isolated from germinating soybean seeds to obstain pH profiles, carbonyl Production, carotene bleaching abilities, and stability to heat. The roles of these lipoxygenase isoenzymes in the generation of volatile carbonyl compounds were investigated to associate with off-flavor and odor of soybean sprouts cooked to different temperatures. Lipoxygenase isoenzymes were isolated from soybean sprouts using ammonium sulfate fractionation, gel filtration and ionexchange chromatography. Two main lipoxygenases exhibited maximum activity at pH 6.5 (lipoxygenase 2) and at pH 9.5 (lipoxygenase 1), respectively. Both lipoxygenase 1 and 2 produced 280 nm absorbing carbonlys and bleached carotene. The abilities of hydroperoxide formation, 280 nm absorbing carbonyl production and carotene bleaching of lipoxygenase isoenzymes were decreased significantly as the cooking temperature raised. Sensory evaluation data presented that raw and $50^{\circ}C$ cooked soybean sprouts showed significantly higher grassy odor than $80^{\circ}C$and $100^{\circ}C$ cooked soybean sprouts. On the other hand beany odor was significantly higher in $50^{\circ}C$ and $80^{\circ}C$ cooked soybean sprouts than in raw and $100^{\circ}C$ cooked soybean sprouts. These results indicate that lipoxygenase plays a role in the development of off-odor and flavors in soybean sprouts under the condition of chewing and inadequate heating.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.2
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• pp.55-62
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• 2021

This study aims to reduce the rancid odor generated during the fermentation process of kimchi by inserting zinc oxide (ZnO) into an inorganic porous material with a high surface area to decompose or adsorb the fermentation odor. ZnO activated by the presence of moisture exhibits decomposition of rancid odors. Mixed with Titanium dioxide (TiO₂), a photocatalyst. To manufacture the packaging liner used in this study, NaOH, ZnCl₂, and TiO₂ powder were placed in a tank with diatomite and water. The sludge obtained via a hydrothermal ultrasonication synthesis was sintered in an oven. After being pin-milled and melt-blended, the powders were mixed with linear low-density polyethylene (L-LDPE) to make a masterbatch (M/B), which was further used to manufacture liners. A gas detector (GasTiger 2000) was used to investigate the total amount of sulfur compounds during fermentation and determine the reduction rate of the odor-causing compounds. The packaging liner cross-section and surface were investigated using a scanning electron microscope-energy dispersive X-ray spectrometer (SEM-EDS) to observe the adsorption of sulfur compounds. A variety of sulfur compounds associated with the perceived unpleasant odor of kimchi were analyzed using gas chromatography-mass spectrometry (GC-MS). For the analyses, kimchi was homogenized at room temperature and divided into several sample dishes. The performance of the liner was evaluated by comparing the total area of the GC-MS signals of major off-flavor sulfur compounds during the five days of fermentation at 20℃. As a result, Nano-grade inorganic compound liners reduced the sulfur content by 67 % on average, compared to ordinary polyethylene (PE) foam liners. Afterwards SEM-EDS was used to analyze the sulfur content adsorbed by the liners. The findings of this study strongly suggest that decomposition and adsorption of the odor-generating compounds occur more effectively in the newly-developed inorganic nanocomposite liners.

• International Journal of Industrial Entomology and Biomaterials
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• v.32 no.2
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• pp.60-68
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• 2016

Pheromone orientation in moths is an exemplar of olfactory sensitivity. To avoid cross mating, the responses of males to pheromone blends must be high specificity and temporal resolution. We tested the effects of olfactory self- and cross-adaptation of pheromone compounds and mixtures in Spodoptera litura moths by electroantennogram (EAG) recordings. The challenge of S. litura antennae to a pulse train of its own pheromone blends of Z9,E11-14:OAc and Z9,E12-14:OAc with 200 ms on/off and 1 s on/off indicated that the repetitive stimulation by 200 ms on/off with high dosages resulted in greater adaptation than that by 1 s on/off with low dosages and the adaptation index of Z9,E11-14:OAc in all treatments is significantly larger than that of Z9,E12-14:OAc, suggesting that high dosages with more frequent stimulation prefer to induce sensory adaptations and a different odor coding exist between the two components in the antennal periphery in this moth. The cross-adaptation EAG test among the two pheromone compounds and Z7-12:OAc and Z9-14:OH from congeneric species of S. litura showed that each of these compounds adapted the antenna more to that specific compound. The significantly higher adaptation to Z7-12:OAc and Z9-14:OH than to the pheromone components of S. litura induced by themselves suggested that both of them are coded by specific odor receptor neurons which are different from those tuned to the pheromone components of S. litura . Thus, we proposed that Z7-12:OAc and Z9-14:OH may play an important role in avoidance of heterospecific mating between S. litura and its sympatric moth species.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.149-149
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• 2016

Pheromone orientation in moths is an exemplar of olfactory sensitivity. To avoid cross mating, the responses of males to pheromone blends must be high specificity and temporal resolution. We tested the effects of olfactory self-and cross-adaptation of pheromone compounds and mixtures in Spodoptera litura moths by electroantennogram (EAG) recordings. The challenge of S. litura antennae to a pulse train of its own pheromone blends of Z9,E11-14:OAc and Z9,E12-14:OAc with 200 ms on/off and 1 s on/off indicated that the repetitive stimulation by 200 ms on/off with high dosages resulted in greater adaptation than that by 1 s on/off with low dosages and the adaptation index of Z9,E11-14:OAc in all treatments is significantly larger than that of Z9,E12-14:OAc, suggesting that high dosages with more frequent stimulation prefer to induce sensory adaptations and a different odor coding exist between the two components in the antennal periphery in this moth. The cross-adaptation EAG test among the two pheromone compounds and Z7-12:OAc and Z9-14:OH from congeneric species of S. litura showed that each of these compounds adapted the antenna more to that specific compound. The significantly higher adaptation to Z7-12:OAc and Z9-14:OH than to the pheromone components of S. litura induced by themselves suggested that both of them are coded by specific odor receptor neurons which are different from those tuned to the pheromone components of S. litura. Thus, we proposed that Z7-12:OAc and Z9-14:OH may play an important role in avoidance of heterospecific mating between S. litura and its sympatric moth species.

• Journal of Microbiology and Biotechnology
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• v.30 no.10
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• pp.1510-1515
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• 2020

Trimethylamine (TMA) is a well-known off-odor compound in fish and fishery products and is a metabolic product of trimethylamine N-oxide (TMAO) generated by the enzymatic action of microorganisms. The off-odor is a factor that can debase the value of fish and fishery products. The present study aimed to remove TMA using lactic acid bacteria (LAB). A total of fifteen isolates exhibiting the TMA reduction efficacy were isolated from Korean traditional fermented foods. Among these isolates, five LAB isolates (Lactobacillus plantarum SKD 1 and 4; Lactobacillus paraplantarum SKD 15; Pediococcus stilesii SKD 11; P. pentosaceus SKD 14) were selected based on their high TMA reduction efficacy. In situ reduction of TMA efficacy by the LAB cell-free supernatant was evaluated using a spoiled fish sample. The results showed effective TMA reduction by our selected strains: SKD1 (45%), SKD4 (62%), SKD11 (60%), SKD14 (59%), and SKD15 (52%), respectively. This is the first study on TMA reduction by the metabolic activity of LAB and in situ reduction of TMA using cell-free supernatant of LAB. The present finding suggests an economically useful and ecofriendly approach to the reduction of TMA.