• Food Science and Preservation
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• v.24 no.1
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• pp.27-35
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• 2017

Microbiological, physicochemical, and organoleptic properties of fresh-cut vegetables (FVs), carrots, green peppers, cherry tomatoes, and paprika after X-ray irradiation were evaluated to verify food quality suitable for the immune-depressed patients. Total concentrations of aerobic bacteria in non-irradiated samples, except for cherry tomatoes, were 1.63-3.34 log CFU/g. Irradiation dose exceed 0.4 kGy was used for carrots and green peppers whereas the sterilization dose of 0.2 kGy was used for both cherry tomatoes and paprika. A dose of 0.4 kGy was tentatively determined as the minimum allowable dose for sterilization of the FVs, based on $D_{10}$-values of X-ray irradiation (0.11-0.32 kGy) for Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium inoculated on the samples. With respect to the physiological properties, only hardness was significantly decreased as the absorbed dose increased; however, there were no significant differences in hardness of the sterilized samples using X-rays at 0.4 kGy compared with those of non-irradiated samples (p<0.05). Moreover, overall acceptance scores of the sterilized FVs were higher than 5.0 points on a 7-point scale, indicating a good organoleptic quality. In a survey on preference of hospitalized patients with cancer (n=50), the average scores for the sterilized FVs, except for carrots, were higher than 4.0 points. In conclusion, it is considered that the FVs, except for carrots, sterilized using X-rays at 0.4 kGy could be served to immune-depressed patients as hygienically safe foods with acceptable organoleptic properties.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.10
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• pp.1437-1449
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• 2006

Thirty six pre-weaned Barbari kids at 4 months age were reared on four rations computed using coarse cereal grains and by-products of pulses and oil seeds with Crude Protein (CP) and Total Digestible Nutrients (TDN) of 12 and 55% (Low protein Low energy); 12 and 60% (Low protein High energy); 14 and 55% (High protein Low energy); and 14 and 60% (High protein High energy), respectively. After 180 days on feed, male animals ($4{\times}5=20$) were slaughtered to study the effect of diet on carcass characteristics and meat quality. To asses the effect, if any, of such diet on product quality, meat balls were prepared and evaluated for quality changes when fresh as well as during storage ($-20{\pm}1^{\circ}C$). Feeding a ration with CP12 and TDN 60% (LH) to kids produced animals with highest slaughter weight (20.3 kg) yielding higher carcass weight and dressing percentage, lean (65.6%) and fat (6.6%) contents with low bone and trim losses. Although total variety meat yield was markedly higher in HL, the non-carcass fat deposition was relatively higher in LH carcasses. The water activity ($a_w$) of fresh goat meat ranged from 0.994-0.995 and total cholesterol 72.8-90.5 mg/100 g meat. The pH was high in HL and HH meat resulting in decreased ($p{\leq}0.05$) extract release volume (ERV). Meat balls were prepared using meat obtained from goats fed different rations (treatments) and stored at $-20{\pm}1^{\circ}C$. They were evaluated on day 0 and months 1, 2, 3, 4 for physicochemical, microbiological and organoleptic changes. Overall moisture (%), $a_w$, TBA number and pH value were 67.9, 0.987, 0.17, 6.6 respectively and were not affected by treatments except pH that was significantly ($p{\leq}0.01$) lower on LH. As the storage period advanced moisture, pH, $a_w$ and TBA number increased irrespective of treatments. Feeding various diets had no marked effect on microbial load of meat balls but with increasing storage period Standard Plate Count (SPC) and psychrotrophs declined ($p{\leq}0.01$). Treatment LL and LH produced meat balls with better flavour.

• Food Science and Preservation
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• v.9 no.1
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• pp.19-27
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• 2002

The effect of gamma irradiation was investigated on the microbiological and physicochemical qualities of boiled-dried anchovies (large- and smallsized) packed in PVC film (0.06 ㎜) during storage at 15$\pm$1$\^{C}$ for 6 months. On the other hand, thermoluminescence characteristics of minerals extracted from the sample were analyzed to evaluate its possibility in detecting the irradiated anchovies. The samples were contaminated by microbial levels of 104∼106 CFU/g in total aerobic bacterial counts and negative in coliforms, which were different depending on the sample sizes. Gamma irradiation at 3 kGy was effective for improving the hygienic quality of both samples for 6 months, keeping the microbial population less than 20 CFU/g. Besides it was not detrimental to the quality attributes, such as instrumental color parameters L, a, b, ΔE), browning, TBA value, volatile basic nitrogen, trimethylamine-N and sensory properties(appearance, color, odor, tape, overall acceptability). However, storage conditions (time, temperature, packing) showed a critical factor nfluencing the quality changes of dried anchovies. Thermoluminscence analysis was prove to distinguish irradiated from non-irradiated anchovies by comparing both temperature at which glow curves appear and the curve intensity, that was possible even after 6 months at - 20$\^{C}$.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.780-786
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• 2010

This study compared the effects of autoclaving (AC; $121^{\circ}C$ for 15 min), gamma (GR), and electron beam irradiation (EB; 0-20 kGy) on the microbial, physicochemical, and sensory properties of ready-to-eat bulgogi during storage at $35^{\circ}C$ for 90 d. No viable cells were observed (p<0.05) upon AC, GR or EB at more than 15 kGy. However, adverse effects such as tenderization and deterioration of sensory properties were induced in bulgogi upon AC and high dose irradiation. Especially, the hardness and sensory qualities (texture and taste) of the AC-treated samples were extremely deteriorated (p<0.05). These results indicate that use of GR and EB (15 kGy) can ensure the microbial safety of bulgogi without compromising the hardness and sensory properties (texture, taste and flavor).

• Food Science of Animal Resources
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• v.41 no.6
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• pp.950-966
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• 2021

This study investigated the effects of lemon extract powder and vinegar powder on the physicochemical and microbiological characteristics of pork sausages naturally cured using white kimchi powder during storage for 30 days. Six batches were included: control (0.01% sodium nitrite and 0.05% sodium ascorbate); treatment 1 (0.3% white kimchi powder and 0.5% lemon extract powder); treatment 2 (0.3% white kimchi powder and 1.0% lemon extract powder); treatment 3 (0.3% white kimchi powder and 0.5% vinegar powder); treatment 4 (0.3% white kimchi powder and 1.0% vinegar powder); and treatment 5 (0.3% white kimchi powder, 0.5% lemon extract powder, and 0.5% vinegar powder). Treatment 2 had significantly lower pH values and higher cooking loss than the other batches (p<0.05). Treatments 1, 2, and 5 had similar (p>0.05) CIE a^* as the control, while treatments 3 and 4 showed significantly lower values (p<0.05). The residual nitrite content in naturally cured products was lower than the control (p<0.05), while treatments 1 and 2 showed significantly higher nitrosyl hemochrome content and curing efficiency (p<0.05). TBARS values were similar for all treatments and the control (p>0.05). Treatments 1 and 2 showed significantly reduced aerobic plate counts (APC; p<0.05) than the control and other treatments. However, across all batches, TBARS values and APC significantly increased during storage (p<0.05). Our results suggest that lemon extract powder, rather than vinegar powder, may offer a promising alternative for supplementing the functions of nitrite in naturally cured sausages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.6
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• pp.810-817
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• 2023

Oysters are a highly consumed seafood throughout Korea, but they have a short shelf life because they support rapid microbial growth due to their of high moisture content and fragile muscle tissue. We examined natural food additives including lactic acid bacteria fermentation powder, rosemary extract, and lemon juice for their ability to preserve raw oyster Crassostrea gigas quality. Samples were stored at 4℃, and microbiological and physicochemical analyses were conducted. Among the natural additives tested, lemon juice was the most effective. Lemon juice was thus applied at different concentrations (50-300 ppm) to quantitatively assess its effect on total viable cell count, pH, glycogen, soluble protein, and turbidity. 200 ppm was confirmed to be optimal, and is projected to extend shelf life by 2 days compared to the control group.

• Journal of the Korean Society of Food Culture
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• v.34 no.2
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• pp.224-232
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• 2019

This study evaluated the physicochemical and microbial quality characteristic of seasonal commercial kimchi for hygienic safety levels. The pH of seasonal commercial kimchi was 3.84-6.36 and the titratable acidity and salinity of the samples were 0.21-1.16 and 1.19-1.54%, respectively. The content of nitrate and nitrite in the commercial kimchi were lower in the spring and summer, which was affected by acidic condition of the kimchi depending on fermentation. Heavy metal contents in commercial kimchi are not an issue because they were detected only at very low levels. The total aerobic bacteria and coliforms counts ranged from 5.25 to 8.44 Log CFU/g and 0.00 to 5.08 Log CFU/g, respectively. The total aerobic bacteria and coliforms were detected more in summer than in the other seasons. E. coli was detected in three of the samples tested. Food-borne pathogens were not detected in any of the samples except for B. cereus. B. cereus was detected in the fall in more than 70% of samples. These results suggest that commercial kimchi distributed in the fall maintain the quality properties and the microbiological safety of kimchi compared to the other seasons. Therefore, further studies as an effective distribution system for the particular seasons will be needed to guarantee the hygienic safety levels of commercial kimchi required by the consumers.

• the MEAT Journal
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• s.35 winter
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• pp.46-55
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• 2008

The microbiological and physicochemical properties of irradiated (2 kGy) or non-irradiated fermented meats processed with or without a commercial starter culture were evaluated during fermentation and aging. The pH of irradiated (2 kGy) fermented meats with starter cultures dramatically decreased during fermentation and aging (p<0.05), and the final pH was 4.25. The total aerobic counts and lactic acid bacteria counts reflected the addition of the starter culture. As the fermentation progressed, the total aerobic counts closely paralleled the lactic acid bacteria counts. The TBARS values of irradiated fermented meats increased regardless of the treatment during fermentation and aging. These results show that the irradiated(electron-beam) meat/fat resulted in the reduction of the total microbes and survives lactic acid bacteria. The use of starter cultures in meat batters post-irradiation may be useful for the production of fermented meats.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.308-313
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• 2007

The microbiological and physicochemical properties of irradiated (2 kGy) or non-irradiated fermented meats processed with or without a commercial starter culture were evaluated during fermentation and aging. The pH of irradiated (2 kGy) fermented meats with starter cultures dramatically decreased during fermentation and aging (p<0.05), and the final pH was 4.25. The total aerobic counts and lactic acid bacteria counts reflected the addition of the starter culture. As the fermentation progressed, the total aerobic counts closely paralleled the lactic acid bacteria counts. The TBARS values of irradiated fermented meats increased regardless of the treatment during fermentation and aging. These results show that the irradiated (electron-beam) meat/fat resulted in the reduction of the total microbes and survives lactic acid bacteria. The use of starter cultures in meat batters post-irradiation may be useful for the production of fermented meats.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.47-50
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• 1984

Effects of irradiation on microbiological, physicochemical aspects and quality of onion powder were investigated during three months storage. Total bacteria and coliform were sterilized by irradiation of 7 and 5 kGy, respectively and no microorganisms were grown after three months storage at $30{\pm}1^{\circ}C$. $D_{10}$ value of total bacteria was 1.64 kGy. Proximate composition of onion powder was not remarkably changed during storage except the slight decrease of pyruvic acid content. Color difference could not be distinguished by naked eye but was slightly changed by the mechanical measurement.