• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.93-99
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• 2013

This study was conducted to evaluate the effect of gamma irradiation on the microbiological and sensory characteristics of frozen Bibimbap. Frozen Bibimbap vegetables were contaminated by microbial levels of $2.70{\sim}6.67log\;CFU\;g^{-1}$ in total aerobic bacteria. Frozen Bibimbap was contaminated by microbial levels of $4.8log\;CFU\;g^{-1}$ in total aerobic bacteria, but microorganisms in gamma-irradiated samples at above 25 kGy were not found at detection limit less then $1log\;CFUg^{-1}$. Sensory characteristics of the gamma-irradiated Bibimbap were decreased depending upon the irradiation dose, and sensory scores of the samples irradiated with doses higher than 10 kGy were significantly decreased. Therefore, the application of combination of the various food processing technology should be considered for the sterilization of Bibimbap, without any deterioration of quality occurred by high dose irradiation.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.57-64
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• 2000

An optional ingredient, Gatt(Brassica juncea) was adopted to improve the quality of Dongchimi during fermentation. The final weight percentage of Gatt in Dongchimi was adjusted to 0, 3, 5, 10, or 15%, per radish. Sensory and microbiological characteristics were determined during fermentation at 10$^{\circ}C$ for 45 days. The effect was varied depending on the amounts of Gatt, but Dongchimi fermented with 5% Gatt was most favored for color, flavor, taste, and overall acceptability in sensory evaluation. According to the quantitative descriptive analysis for the product, the liquid portion of Dongchimi steadily became clearer and less sour in proportion to the amount of added Gatt. The fermentation retarding action of Gatt at the initial stage of Dongchimi fermentation was clearly seen as above. However, the addition of Gatt at above 15% of Chinese radish was not desirable due to the accelerated fermentation at the later stage. The general changing patterns in typical characteristics of fermentation including microbial counts were comparable with each other depending on the treatments. And favorable Dongchimi could be prepared by fermenting with 5% Gatt at the given condition.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1736-1743
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• 2017

Sourdough is made by fermentation of dough by lactic acid bacteria (LAB) and yeast to improve bread properties like volume, flavor, and texture. A Korean traditional sourdough was made by fermenting rice flour with rice wine (makgeolli) and used to make sponge-like bread (jeung-pyun). The aim of this study was to investigate the microbial diversity of makgeolli products and their influence on the organoleptic quality of jeung-pyun. Three commercial makgeolli were tested for jeung-pyun production, with each product exhibiting varied dough swelling rates and organoleptic qualities, and among them, J-product was ranked highest in texture and taste. Microbial analysis of the three makgeolli also showed a big difference in their population and diversity. J-product had the highest LAB and yeast counts, and the predominant species were Lactobacillus casei, Lactobacillus brevis, Leuconostoc pseudomenteroides, and Saccharomyces cerevisiae. Using J-product, sourdough was fermented at $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$, and the microbial growth in and textural properties of jeung-pyun were examined by instrumental and sensory tests. At high temperature ($35^{\circ}C$), the rates of dough swelling and acidification were fast due to rapid microbial growth mainly caused by LAB, resulting in a short leavening time and soft and sour jeung-pyun. Sensory tests showed consumer preference for the soft and mild-sour jeung-pyun. This study shows that LAB in makgeolli play key roles in production of jeung-pyun, influencing the textural and sensory properties. For the production of high-quality jeung-pyun, development of LAB starters with high gas productivity and low acidity and establishment of an optimal fermentation procedure for rice dough are necessary.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.380-386
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• 2000

Electron beam (EB) was applied to study the sterilizing techniques for powdered red pepper and ginger by determining their quality over gamma radiation (GR) from the microbiological and organoleptic points of view. The samples showed high microbial loads, such as $10^5{\sim}10^6\;CFU/g$ in total aerobic bacteria, negligible levels in yeasts & molds and $10^2\;CFU/g$ in coliforms. EB irradiation at 5 kGy resulted in the reduction of microbial loads by 2 to 3 log cycles, thereby decreasing the levels of total bacteria to $10^2{\sim}10^3\;CFU/g$ and resulting in negative in coliforms. Decimal reduction doses $(D_{10})$ value on the initial bacterial loads in red pepper were $1.50{\sim}1.54\;kGy$ in EB and $1.68{\sim}1.80\;kGy$ in GR, while powdered ginger showed $1.30{\sim}2.27\;kGy$ in EB and $1.45{\sim}2.77\;kGy$ in GR, respectively. EB and GR showed a similar effect on microbial decontamination for both samples. Microbial populations in stored samples for 4 months at room temperature were not remarkably different from the initial loads in all samples. Irradiation caused little changes in Hunter's color parameters, but that were changable during storage. Sensory evaluations on color and odor of powdered samples indicated that no significant differences were observed among the all samples compared. These results revealed that EB irradiation at optimal dose levels for microbial control was not detrimental to the sensory quality of powdered red pepper and ginger.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.160-169
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• 2009

This study was performed to examine the quality characteristics of red ginseng wet noodles prepared with additions of carrageenan, xanthan gum, or guar gum. The quality characteristics of the samples were estimated in terms of their general composition, color differences, cooking characteristics, textural attributes, sensory qualities, and microbial growth during storage. The results were as follows. Protein content was significantly decreased in the guar gum added group and ash content was significantly increased in the carrageenan added group (p<0.05). Lipid, water, and Na contents were not significant different among the groups. However, water binding capacity was significantly increased in the group with added xanthan gum. Over 10 weeks of storage, water contents did not differ significantly between the xanthan gum and guar gum added groups. In all the added gum groups, L- and a- values were significantly increased whereas b- values decreased (p<0.05). In texture profile analyses, chewiness, cohesiveness, hardness, and springiness were significantly increased in the carrageenan and xanthan gum added groups (p<0.05). According to sensory evaluations, surface color, red ginseng flavor, red ginseng taste, softness, chewiness, and overall acceptability were considered very good in the xanthan gum and guar gum added groups (p<0.05). Therefore, the red ginseng noodles containing xanthan gum and guar gum were deemed most preferable and presented the safest shelf-life during 10 weeks at -$10^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.39 no.3
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• pp.341-347
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• 2012

The objective of this study was to investigate the combined effect of electron beam irradiation (EB) and onion peel extracts and selected flavorings on microbiological and sensory quality of pork jerky. Total aerobic bacteria were detected in the range of $3.87{\pm}0.30{\sim}4.60{\pm}0.12$ log CFU/g in all samples. Addition of both onion peel extract and flavoring showed the decrease of total aerobic bacterial count in pork jerky. No viable cells were observed after EB at 4 kGy. Sensory evaluation indicated that the EB-treated pork jerky with 0.5% barbecue flavoring did not show any difference in overall acceptability compared with the control. Therefore, combined use of EB with onion peel extracts and barbecue flavoring may enhance the safety of pork jerky with proper sensory quality.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.1
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• pp.85-91
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• 2013

Korean traditional rice wine, Makgeolli, has been widely consumed and increasingly popular in Korea. In this study, we examined Makgeolli supplemented with cranberries (0, 5, 10 and 15% by rice weight) during fermentation for seven days for the various quality characteristics : pH, total acidity, soluble contents, color, reducing sugars, alcohol contents, and DPPH free radical scavenging activities, total flavonoids, microbial properties, and sensory properties. After the pH value decreased from a range of 4.40~5.63 to 3.83~3.94 up to day 3, the pH gradually increased until day 7. As fermentation proceeded, soluble contents and reducing sugar increased in most of the samples, with a temporary reduction after day 2. There were no differences in L and b color values, but the "a" value showed significant differences with the rate of cranberry added. The DPPH free radical scavenging activity and total flavonoid content of cranberry Makgeolli were higher than those of the control. After fermentation for seven days, the alcohol content ranged from 14.57 to 17.40%, while total acidity levels were within the range of 0.50 to 0.54%. Yeast cell counts increased until day 3 and then, gradually deceased. In the sensory evaluation, Makgeolli with 10% cranberry showed the highest overall acceptance.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.139-150
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• 2019

This study aimed to determine the suitable point of sale and consumption of different quality grade (QG) Hanwoo short loin during aging period, based on physicochemical, sensory, and microbiological quality. Short loins obtained from the carcasses of 13 Hanwoo steers and 2 bulls with 5 different QGs (1++, 1+, 1, 2, and 3) were analyzed over 28 d. QG and aging time had significant effect on water holding capacity, color, shear force, total volatile basic nitrogen (TVBN) content, and sensory traits. Higher QG groups generally exhibited a lower shear force, nucleotide content, and water holding capacity, and higher $L^*$, $a^*$, and $b^*$ values. Acceptable tenderness (shear force <5.4 kg) in QG 1++, 1+, 1, and 2 was achieved on days 7, 14, 16, and 18, respectively, and QG 3 showed a shear force of 6.8 kg, even after 28 d. Regardless of QG, TVBN content below threshold levels (20-30 mg%) was observed throughout the 28 d aging period, while total plate counts above 7 Log CFU/g were seen at 21 d. In conclusion, it is recommended that Hanwoo beef with QG 1++, 1+, and intermediate QG (1 and 2) should be sold or consumed between 7 and 21, 14 and 21, 16 and 21 d, respectively. Beef with QG 3 should be sold or consumed within 21 d, based on microbial growth, even though it has not achieved desirable tenderness. For this reason, an additional tenderizing process is recommended before this beef is ready for consumption.

• Food Science of Animal Resources
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• v.37 no.4
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• pp.494-501
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• 2017

This study investigated the effect of injecting pineapple concentrate and honey into low marbled beef in order to enhance its sensory qualities, particularly tenderness and flavor, without compromising its fresh appearance. Beef loin was injected with a solution of 6.0% pineapple concentrate, 2.5% honey, 0.5% monosodium L-glutamate, 0.5% phosphate, and 0.3% salt (w/w) to 120% (w/w) of initial meat weight and stored for 14 d. Non-injected beef loin served as a control. Total aerobic bacterial counts, surface meat color, shear force, reducing sugar content, and sensory evaluation of the beef were analyzed at 0.5, 7, and 14 d of storage. Injection did not affect the total aerobic bacterial counts or color of the beef. However, injection increased the stability of meat color, compared with that of the control, during storage. The shear force value was significantly lower in the injected beef than that in the control. The injected beef had a significantly higher reducing sugar content compared with that of the control. In sensory evaluation, tenderness, juiciness, flavor, and overall acceptance of the injected beef were significantly higher than those of the control at 0.5 d. In conclusion, injection of pineapple concentrate and honey can improve the sensory qualities of low marbled beef, during short storage periods, without changing the fresh appearance of the beef.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.1-5
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• 2014

This study investigated the reduction of microbial population and sensory properties in red pepper powders irradiated by gamma ray, electron beam, and X-ray. Populations of total aerobic bacteria and yeast & molds in red pepper powders were decreased by irradiation treatment in a dose-dependent manner. Gamma ray, electron beam, and X-ray at doses above 8 kGy caused 100% inhibition on growth of aerobic bacteria in red pepper powders. Inhibitory activity of X-ray on sterilization of red pepper powders was significantly equal to or higher compared to gamma ray and electron beam. Color and off flavor in red pepper powders were no significant difference among the control and samples irradiated with gamma ray, electron beam, and X-ray. As a result, the gamma ray, electron beam, and X-ray irradiation can be used to sterilize the microbial growth in red pepper powders without quality loss.