• Title/Summary/Keyword: Microbial qualities

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Effect of Gamma Irradiation and Fumigation on the Biological Qualities of Green, Black, and Oolong Teas

  • Kwon, Joong-Ho;Kausar, Tusneem;Kwon, Yong-Jung;Kim, Jung-Ae;Huh, Eun-Youp;Lee, Kyeong-Yeoll;Saeed, Shafqat
    • Food Science and Biotechnology
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    • v.15 no.1
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    • pp.1-4
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    • 2006
  • The biological qualities of green, black, and oolong teas were monitored by observing their microbial decontamination and insect disinfestation following gamma irradiation (0-10 kGy) and fumigation (MeBr or $PH_3$) during 6-month storage at room temperature. Plodia interpunctella Hubner was found as an important quarantine pest in teas used. In a comparative study, both treatments were found to be effective in disinfecting the stored samples. An irradiation dose of 5 kGy was sufficient to control all microorganisms related to the quality of teas, while fumigation with methyl bromide and phosphine showed no appreciable decontamination effect on the microorganisms. As a result, irradiation was found an effective alternative to fumigants for the improvement of biological tea qualities during storage.

Application of a Prototype of Microbial Time Temperature Indicator (TTI) to the Prediction of Ground Beef Qualities during Storage

  • Kim, Yeon-Ah;Jung, Seung-Won;Park, Hye-Ri;Chung, Ku-Young;Lee, Seung-Ju
    • Food Science of Animal Resources
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    • v.32 no.4
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    • pp.448-457
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    • 2012
  • The predictive ability for off-flavor development and quality change of ground beef was evaluated using a microbial time temperature indicator (TTI). Quality indices such as off-flavor detection (OFD) time, color, pH, volatile basic nitrogen (VBN), aerobic mesophilic bacteria (AMB) counts, and lactic acid bacteria (LAB) counts were measured during storage at 5, 10, 15, and $25^{\circ}C$, respectively. Arrhenius activation energies (Ea) were estimated for temperature dependence. The Ea values for TTI response (changes in titratable acidity (TA)), VBN, AMB counts, LAB counts, and freshness, which is defined based on OFD time for quality indices of ground beef, were 106.22 kJ/mol, 58.98 kJ/mol, 110.35 kJ/mol, 116.65 kJ/mol, and 92.73 kJ/mol, respectively. The Ea of microbial TTI was found to be closer to those of the AMB counts, LAB counts, and freshness. Therefore, AMB counts, LAB counts, and freshness could be predicted accurately by the microbial TTI response due to their Ea similarity. The microbial TTI exhibited consistent relationships between its TA change and corresponding quality indices, such as AMB counts, LAB counts, and freshness, regardless of storage temperature. Conclusively, the results established that the developed microbial TTI can be used in intelligent packaging technology for representing some selected quality indices of ground beef.

Effects of Ozone Treatment and Gamma Irradiation on the Microbial Decontamination and Physicochemical Properties of Red Pepper Powder (고춧가루의 오염미생물 제거 및 이화확적 특성에 관한 오존처리와 감마선 조사의 영향)

  • 이성희;이현자;변명우
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.3
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    • pp.465-467
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    • 1997
  • The comparative effects of ozone treatment and gamma irradiation on the sterilization, physicochemical properties and sensory quality of red pepper powder were investigated. As for the sterilization of microorganisms, 7.5~10 KGy of gamma irradiation completely eliminated the coliforms, yeast and molds, and total aerobic bacteria. On the other hand, ozone treatment failed to eliminate the highly contaminated microbial load, especially total aerobic bacteria. The physicochemical properties including capsaicin, capsanthin, browning, fatty acid compositions and sensory quality were not significantly changed by gamma irradiation up to 10 kGy, whereas ozone treatment caused significant changes in fatty acid compositions and destruction of natural pigments (p<0.05). The above results led us to conclude that gamma irradiation was more effective than ozone treatment for the sterilization and maintenance of physicochemical and sensory qualities of red pepper powders.

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Microbial Decontamination of Angelica gigas Nakai Using Electron Beam Irradiation

  • Jin, You-Young;Shin, Hee-Young;Song, Kyung-Bin
    • Preventive Nutrition and Food Science
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    • v.11 no.4
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    • pp.344-347
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    • 2006
  • This study evaluated the use of electron beam irradiation for decontamination of the Korean medicinal herb, Angelica gigas Nakai. Herb samples were irradiated at doses of 2, 8, and 16 kGy, respectively. Populations of microorganisms in Angelica gigas Nakai decreased by 2$\sim$3 log cycles at 8 kGy irradiation. Electron beam irradiation caused negligible changes in Hunter color L, a, and b values. Sensory evaluations of Angelica gigas Nakai confirmed that irradiation caused no significant changes in the organoleptic properties of the samples. These results suggest that electron beam-irradiated herbs retain a better microbial safety and sensory qualities, compared with the non-irradiated.

Quality Changes During Storage of Cook-chilled Soybean Sprouts

  • Koo, Kyoung-Mo;Kim, Hyoun-Wook;Lee, Dong-Sun;Lyu, Eun-Soon;Paik, Hyun-Dong
    • Food Science and Biotechnology
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    • v.17 no.3
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    • pp.540-546
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    • 2008
  • Sous vide and packaged cook-chilled soybean sprouts were evaluated for physicochemical quality changes and microbial safety during storage for the purposes of shelf-life extension and industrial application. The physicochemical changes assessed were color, texture, and ascorbic acid concentration. The quality of soybean sprouts became worse with increased periods of storage and better in storage temperature of $3^{\circ}C$ more than in $10^{\circ}C$. The concentration of aerobic bacteria decreased from $2.1{\times}10^8$ to $6.0{\times}10^2\;CFU/g$ after pasteurization, but increased during storage. These bacteria are the same shape as anaerobic and hsychrophilic bacteria, but none of these other organisms were detected after heat treatment. The physicochemical qualities of soybean sprouts and microbial safety were better for products stored at $3^{\circ}C$ than at $10^{\circ}C$. In the case of short storage periods, heat treatment at $70^{\circ}C$ for 2 min was most effective for quality and microbial safety.

Aqueous Chlorine Dioxide Treatment Decreases Microbial Contamination and Preserves Sensory Properties of Mackerel During Storage

  • Kim, Yun-Jung;Nam, Sa-Uk;Chae, Hyeon-Seok;Lee, Seoung-Gyu;Song, Kyung-Bin
    • Preventive Nutrition and Food Science
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    • v.12 no.3
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    • pp.181-184
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    • 2007
  • Effect of aqueous chlorine dioxide ($ClO_{2}$) treatment on quality change of mackerel during storage was examined. Mackerel treated with 0, 5, 10, and 50 ppm of $ClO_{2}$ solution, respectively was stored at $4^{\circ}C$. $ClO_{2}$ treatment decreased populations of aerobic bacteria in mackerel during storage. The number of total aerobic bacteria of mackerel treated with 50 ppm $ClO_{2}$ increased from 2.45 to 3.44 log CFU/g after 9 days of storage, while that of the control increased from 3.47 to 4.72 log CFU/g. The pH values of mackerel increased during storage, with no significant changes among treatments. Volatile basic nitrogen values of mackerel were decreased by $ClO_{2}$ treatment. Quality of mackerel treated with $ClO_{2}$ was better than that of the control during storage based on sensory evaluation. These results indicate that aqueous $ClO_{2}$ treatment could be useful for improving the microbial safety and qualities of mackerel.

Effect of Fish Sarcoplasmic Protein on Quality Attributes of No-fat Chicken Sausages Mediated by Microbial Transglutaminase

  • Hemung, Bung-Orn;Chin, Koo Bok
    • Food Science of Animal Resources
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    • v.35 no.2
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    • pp.225-231
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    • 2015
  • Fish sarcoplasmic protein (SP) obtaining from lyophilization was evaluated its effect on the qualities of the no-fat chicken sausages in the presence of microbial transglutaminase (MTG) as compared to sodium tripolyphosphate (STPP). The cooking yields of all sausage samples were not different. Expressible moisture (EM) of sausage samples was reduced by adding fish SP, while the lowest EM values were observed in sausage samples containing STPP. The pH values of sausage samples were increased with the addition of fish SP and STPP. Proximate analysis revealed that the moisture, fat, and protein contents of all samples were not different (p>0.05). Textural properties (TP), measured by texture profile analysis, showed that hardness of no-fat sausages increased upon adding fish SP. However, the highest TP values were found in sausage samples with STPP. The redness values were reduced in sausage samples with STPP, while other color values were not affected by STPP. Sensory evaluation revealed that sausages with fish SP were accepted at the higher level than that of control. However, sausage samples with STPP showed highest TP and acceptability. Thus, partial substitution of STPP by SP would be possible to reduce phosphate level in the chicken sausages.

Quality Characteristics and Microbial Safety of Sunsik with Dandelion (Taraxacum platycarpum) Complex Extract Powder (AF-343) for Home Meal Replacement (간편가정식용 민들레복합추출물 (AF-343) 첨가 선식의 품질특성 및 미생물적 안전성)

  • Ra, Ha-Na;Kim, Hae-Young
    • Korean journal of food and cookery science
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    • v.30 no.5
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    • pp.642-649
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    • 2014
  • We investigated the antioxidant and physicochemical qualities as well as the sensory characteristics, and microbial safety of sunsik containing varied amounts of AF-343, which can help add moisture to the skin and relieve the symptoms of atopic dermatitis. Samples did not show significant differences in pH measurements, but the pH had a tendency to increase with tendencies as increased amounts of AF-343. The total phenolic compound contents and DPPH radical scavenging activity, indicators of biologically active ingredients such as antioxidant, anticancer and antibacterial activity, significantly increased as the amounts of AF-343 increased (p<0.05). In an acceptance test, the samples did not show significant differences, however samples with the 750 mg AF-343 received the highest scores out of all the samples in overall acceptance. All samples were confirmed as microbially safe according to the food code applied to food manufacturers. Aerobic plate counts of the control group were 1.60 log CFU/g, while those of samples with 750 mg AF-343 were 1.70 log CFU/g. E. coli. Pathogenic microorganisms tests were either negative or not detected in all samples.

Antioxidant Activity, Sensory Characteristics, and Microbial Safety of Sunsik with Fermented Turmeric Powder (발효강황 첨가 선식의 항산화적·관능적 및 미생물적 품질 특성)

  • Wu, Xiu Bao;Kim, Eun Kyung;Ra, Ha Na;Byeon, Yang Soo;Kim, Hae Young
    • Korean journal of food and cookery science
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    • v.32 no.5
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    • pp.600-608
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    • 2016
  • Purpose: To investigate the antioxidant, physicochemical sensory, and microbial safety qualities of sunsik containing fermented Curcuma longa L. powder. Methods: Quality characteristics of samples were measured using pH, moisture content, crude ash content, color and sensory evaluation. Antioxidant activities of samples were compared using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) cation radical scavenging activities. Microbial safety of samples were tested for Aerobic plate counts, Salmonella spp., Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli O157:H7. Results: The pH of samples was between pH 5.51 and pH 5.64, which was significantly lower than the optimum microbial living range. The DPPH and ABTS radical activities of sunsik containing 0.8% fermented Curcuma longa L. were significantly increased compared to that of the control (p<0.05). In sensory intensities, sunsik containing 0.8% fermented Curcuma longa L. showed significantly (p<0.05) similar savoy aroma and flavor, spicy aroma, spicy hot flavor, sweet flavor, and throat swallowing values to those of the control samples. Samples of sunsik added 0.8% and 1.2% fermented Curcuma longa L. showed significantly similar overall acceptance values to those of the control. All samples tested were found to free of microbes and microbiologically safe according to the food code standards. Conclusion: The sunsik added with 0.8% or 1.2% fermented Curcuma longa L. powder were successfully developed. we conclude that the developed sunsik with the fermented turmeric powder can be potentially high value products in the highly competitive sunsik food industry.

Shelf Life Extension of White Rice Cake and Wet Noodle by the Treatment with Chitosan (키토산 처리에 의한 흰떡과 생면의 저장성 연장)

  • Lee, Jang-Wook;Lee, Hyang-Hee;Rhim, Jong-Whan
    • Korean Journal of Food Science and Technology
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    • v.32 no.4
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    • pp.828-833
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    • 2000
  • The effect of treatments with alcohol, chitosan, or with both alcohol and chitosan for extending the shelf-life of Korean white rice cake and wet noodle was investigated by measuring quality changes such as total microbial count, pH, and sensory qualities. Total microbial counts for control, alcohol-treated, and 1% lactic acid-treated white rice cakes exceeded the initial putrefactive criterion level of $1{\times}10^{6}\;CFU/g$ at 6, 27 and 20 days of storage, respectively. However, total microbial count of the white rice cake treated with chitosan was still less than the criterion level even at 76 days of storage. In the case of wet noodle, total microbial counts of control and alcohol-treated groups exceeded the criterion level within 7 days of storage, while that of chitosan-treated group was far less than the criterion level even at the end of storage of 82 days. Chitosan treatment extended the shelf-lives of both white rice cake and wet noodle appreciably.

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