Prevalence and Microbial Flora of Chicken Slaughtering and Processing Procedure

설국환,한기성,김현욱,장운기,오미화,박범영,함준상 한국축산식품학회 2012 한국축산식품학회지 Vol.32 No.6

This study has been performed to measure the prevalence and microbial flora on chicken slaughtering as well as the processing process from the months of October to November. Whole-chicken rinsing technique was used in order to analyze the incidence of microorganisms on chicken carcass at the stage before chilling (after evisceration), after chilling and after cutting. The swab technique was used on processing the processed samples, such as working plates and cutting knives. Brine and cooling water from four cooling tubs were taken from each processing processes and were used as samples. Furthermore,the matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) for whole cell fingerprinting in combination with a dedicated bioinformatic software tool was used to identify the isolated microorganisms. Of the tested samples and processes, brine (4.50±0.64 Log CFU/mL) and chicken carcass before chilling (4.15±0.46 Log CFU/mL)showed the highest population of microorganisms; the predominant microbial flora of them were Moellerella wisconsensis (54.84%), a member of the Enterobacteriaceae family, and Escherichia coli (60.36%), respectively. However, the predominant microbial flora of cut carcass was changed to Staphylococcus aureus (27.32%), which is a kind of pathogenic microorganism that can cause a food-borne illness. Therefore, the slaughtering and processing procedure of chicken are needed to be controlled more hygienically.

Soy Protein Isolate, Egg Albumin 및 Konjac의 첨가가 육포의 품질과 저장성에 미치는 영향

설국환,정종연,이의수,유용호,최지훈,배현아,백현동,김천제 한국축산식품학회 2004 심포지움 및 학술발표회 Vol.- No.33

본 연구는 Soy Protein Isolate, Egg Albumin 및 Konjac의 보습제(humectants)를 첨가하여 제조한 육포의 이화학적, 미생물학적 및 관능적 특성 등을 조사하기 위하여 실시되었다. 보습제를 첨가한 처리구들은 대조구보다 높은 수분함량 및 제품수율을 나타내었으며, 낮은 puncture force를 나타내어 우수한 조직감을 보였다. 모든 처리구가 저장기간이 경과함에 따라 지질산패도 및 총균수가 증가하였으나 konjac을 첨가한 처리구에서 대조구에 비해 다소 낮은 TBA가를 나타냈었다. 또한 Soy protein isolate와 konjac을 첨가한 처리구가 다른 처리구에 비해 낮은 총균수를 나타내었다. 따라서 보습제 종류별 육포의 품질에 미치는 영향이 다소 차이는 있었지만, 저장성면에서 육포 제조시 보습제로서 konjac 첨가가 보다 유효한 것으로 판단된다.

Assessment of the Inhibitory Activity of Peptide Extracts from Hanwoo Musculus Longissimus on Angiotensin I-Converting Enzyme

설국환,송지혜,Thirawong Prayad,김현욱,장애라,함준상,오미화,김동훈,이무하 한국축산식품학회 2011 한국축산식품학회지 Vol.31 No.5

This study was performed to measure the angiotensin I-converting enzyme (ACE) inhibitory activity of peptide extracts derived from the enzymatic proteolysis of Hanwoo Musculus longissimus (M. longissimus) during cold storage. Thermolysin (80 ppm, w/w) and protease type XIII (100 ppm, w/w) were injected separately or in combination for the enzymatic proteolysis of sarcoplasmic and myofibrillar proteins prior to storage at 5oC (T1) or at -1oC (T2) in a chilling room for 9days. Beef injected with thermolysin (E2) and thermolysin+protease type XIII (E3) showed a significantly higher degree of hydrolysis at both storage temperatures (p<0.05). During the storage period, T1E2 at day 6 and T1E3 at day 9 showed the strongest ACE inhibitory activity with sarcoplasmic and myofibrillar protein proteolysates. Macromolecules greater than 10,000 Da were removed by ultra filtration, and the filtrates were separated into fractions using gel filtration. Five and three major fractions were collected from S-T1E2-6 and M-T1E3-9 extracts, respectively, and the 4th fraction of the S-T1E2-6extracts showed the highest ACE inhibitory rate of 61.96±7.41%.

Determination of Optimal Storage Condition for Pre-packed Hanwoo Loin

설국환,박두산,오미화,박범영,조성인,이무하 한국축산식품학회 2013 한국축산식품학회지 Vol.33 No.3

The aim of this study was to determine the optimal storage condition of pre-packed Hanwoo beef without freezing. Han-woo loin was purchased from a local distributor at 48 h after slaughter, then sliced in 1.5±0.5 cm thickness, and packed in a polyethylene (PE) tray covered with linear low-density polyethylene (LLDPE) film. The studied factors to set the optimal storage condition were chamber temperature (5, 2.5 and -1o C for 14 d), cooling method (direct and indirect cooling system),and ultraviolet (UV) light irradiation for beef surface sterilization (0, 30, 60, and 120 min). The changes of pH, thiobarbitu-ric acid reactive substances (TBARS) and number of aerobic bacteria were measured during storage. Beef samples stored in -1o C showed the minimal increasing rate in TBARS and microbial growth. After 15 d of storage, there was no significant difference in pH and TBARS values. However, the microbial population of beef stored in direct type cooling chamber (4.25±0.66 Log CFU/g) was significantly lower than that of beef stored in indirect type chamber (6.47±0.08 Log CFU/g)(p<0.05). After 4 d of storage, 60 or 120 min UV light irradiated beef samples showed significantly lower microbial popu-lation, and at 14 d of storage, 60 min UV irradiated beef sample showed significantly lower microbial population (3.14±0.43 Log CFU/g) than control (4.46±0.13 Log CFU/g) (p<0.05). However, TBARS values of 60 or 120 min UV light irradiated beef samples were significantly higher than non-irradiated beef sample after 4 d of storage (p<0.05).

The Effect of the Water Extracts of Digestive Medicinal Plants on the Shelf-life of Pork Patties

설국환,설현철,Thirawong Prayad,김현욱,장애라,함준상,오미화,김동훈,이무하 한국축산식품학회 2011 한국축산식품학회지 Vol.31 No.1

The Effect of the Water Extracts of Digestive Medicinal Plants on the Shelf-life of Pork PattiesThis study was performed to examine the possibility of water extracts of several digestive medicinal plants (DMPEs),such as Amomum tasoko, Alpinia oxyphylla, Citrus unshiu, and Myristica fragrans, as a natural antioxidant. Total phenol contents of each extract were expressed as gallic acid equibalents (GAE) and those were significantly different among A. tasoko (39.87±5.77 mg GAE/g), A. oxyphylla (30.28±3.36 mg GAE/g), C. unshiu (28.13±5.01 mg GAE/g) and M. fragrans (6.36±0.30 mg GAE/g) (p<0.05), and extract of A. tasoko showed significantly higher antioxidative effect than butylated hydroxyanisole (BHA) on linoleic acid peroxidation at 72 h after incubation (p<0.05). Addition of extracts in pork patties did not affect the pH value and total microbes during cold storage. However, thiobarbituric acid reative substances (TBARS)of treated patties were lower in dose dependant manner than that of control as storage period increased (except patties treated with C. unshiu extract), and patties treated with 0.5% A. tasoko extract showed no significant difference with patties treated with 0.5% BHA at day 7.

유산균의 곰팡이 억제 활성

설국환,유자연,윤정희,오미화,함준상 한국낙농식품응용생물학회 2019 Journal of Dairy Science and Biotechnology (JMSB) Vol.37 No.2

Food spoilage by fungi is responsible for considerable food waste and economical losses. Among the food products, fermented dairy products are susceptible to deterioration due to the growth of fungi, which are resistant to low pH and can proliferate at low storage temperatures. For controlling fungal growth in dairy products, potassium sorbate and natamycin are the main preservatives used, and natamycin is approved by most countries for use in cheese surface treatment. However, a strong societal demand for less processed and preservative-free food has emerged. In the dairy products, lactic acid bacteria (LAB) are naturally present or used as cultures and play a key role in the fermentation process. Fermentation is a natural preservation technique that improves food safety, nutritional value, and specific organoleptic features. Production of organic acids is one of the main features of the LAB used for outcompeting organisms that cause spoilage, although other mechanisms such as antifungal peptides obtained from the cleavage of food proteins and competition for nutrients also play a role. More studies for better understanding these mechanisms are required to increase antifungal LAB available in the market.

옛 친구들과의 對話

薛國煥 관훈클럽 1970 관훈저널 Vol.- No.16

Effect of Medicinal Plant Extract Incorporated Carrageenan Based Films on Shelf-Life of Chicken Breast Meat

설국환,주범진,김현욱,장운기,함준상,오미화,박범영,이무하 한국축산식품학회 2013 한국축산식품학회지 Vol.33 No.1

This study was performed to examine the possibility of water extracts for several medicinal plants, such as Amomum tsaoko,Alpinia oxyphylla, and Citrus unshiu, as an active packaging ingredient for prevention of lipid oxidation. Chicken breast meats were packed with medicinal plant extracts incorporated carrageenan based films and their physico-chemical and microbial properties during storage at 5oC were investigated. In chicken meat samples packed with A. tsao-ko (TF) or A. oxyphylla (OF) extract incorporated carrageenan based films, pH value, thiobarbituric acid reactive substances (TBARS),and the population of total microbes were significantly lower than those of the negative control (film of no extract was incorporated,CF) after 5 d of storage (p<0.05). Especially, TBARS value of TF (0.12±0.01 mg malonaldehyde/kg meat) was significantly lower than chicken meat samples packed with positive control (ascorbic acid incorporated film, AF, 0.16±0.01mg malonaldehyde/kg meat) at 3 d of storage, and it means TF has enough antioxidative activity to prevent the lipid oxidation of chicken meat. However, there was no consistent effect on VBN values of chicken meats packed with medicinal plant extracts incorporated films during storage. Based on the obtained results, it is considered that A. tsao-ko extract has potential for being used as a natural antioxidant ingredient in active packaging areas.

닭 도계 및 가공공정 중 유해미생물의 분포와 항생제 감수성

설국환(Kuk-Hwan Seol),김기현(Ki Hyun Kim),조수미(Su-Mi Jo),김영화(Young Hwa Kim),김현욱(Hyun-Wook Kim),함준상(Jun-Sang Ham) 충남대학교 농업과학연구소 2015 농업과학연구 Vol.42 No.1

This study was performed to analyze the distribution and antimicrobial resistance of pathogenic microorganisms isolated from the carcass and environments of chicken processing plant located in Gyeonggi province from October to November in 2010. Chicken slaughterhouse was visited 3 times and totally 40 samples were collected from chicken carcass before and after washing (n=14), chicken cuts (n=7), cooling water (n=8), brine (n=2), cutting knives (n=7) and working plate (n=2). Whole-chicken rinsing technique (for chicken carcasses) and swab technique (for working plate and knives) were used to analyze the distribution of pathogenic microorganisms. In addition, brine and chilling water from storage tanks were gathered using sterilized tubes and used as samples. The matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) for whole cell fingerprinting in combination with a dedicated bioinformatic software tool was used to identify the isolated microorganisms. The pathogenic microorganisms, such as Bacillus cereus (n=8) and Staphylococcus aureus (n=9), were isolated form the chicken processing process (chicken carcasses of before and after chilling, chicken cuts, and working plate). The antimicrobial susceptibility of those isolated microorganisms was analyzed using 21 antimicrobial agents. In the case of B. cereus, it showed 100% of resistance to subclasses of penicillins and peptides, and it also resistant to cephalothin, a member of critically important antimicrobials (CIA), however there was no resistance (100% susceptible) to vancomycin and chloramphenicol. S. aureus showed 100% resistance to subclasses of peptides and some of penicillins (penicillin and oxacillin), however, it showed 100% susceptibility to cephalosporins (cefazolin and cephalothin). All of the tested pathogens showed multi drug resistance (MDR) more than 4 subclasses and one of B. cereus and S. aureus showed resistance to 9 subclasses. After the ban on using the antimicrobials in animal feed in July 2011, there would be some change in microbial distribution and antimicrobial resistance, and it still has a need to be analyzed.

유우 사육환경 및 원유의 미생물 및 항생제 내성 분석

설국환 ( Kuk Hwan Seol ),이승규 ( Seung Gyu Lee ),김현욱 ( Hyoun Wook Kim ),함준상 ( Jun Sang Ham ),장애라 ( Ae Ra Jang ),한기성 ( Gi Sung Han ),김동훈 ( Dong Hun Kim ),오미화 ( Mi Hwa Oh ) 한국유가공기술과학회 2010 Journal of Dairy Science and Biotechnology (JMSB) Vol.28 No.2

In recent times, antimicrobial resistance has been a concern because of its relation to national health and food safety. In this study, we reviewed the management of antibiotics and antimicrobial-resistant microorganisms in domestic and foreign countries and analyzed microorganisms and antimicrobial resistance in dairy farms and raw milk. The isolates from dairy farms were Micrococcus spp., Staphylococcus chromogens, Escherichia coli, Bacillus licheniformis, Escherichia coli O157:H7, Pseudomonas plecoglossicida, Enterobacter spp., and Kluyvera intermedia. Rummeliibacillus stabekisii, Paenibacillus badius, Pantoea agglomerans, B. oleronius, B. fusiformis, and B. badius were isolated from feed E. coli and Kurthia gibsonii, from feces and S. pasteuri, S. aureus, S. chromogenes, and Salmonella spp., from raw milk. Pathogens isolated from dairy farms and raw milk were tested for susceptibility to 20 types of antibiotics. E. coli (EAEC) and E. coli O157:H7 (EHEC) isolated from dairy farms, E. coli (EAEC) isolated from feces, and Salmonella spp. isolated from raw milk showed resistance to multiple antibiotics. These results show that antimicrobial-resistant microorganisms should be more effectively managed to improve the safety of dairy farms.