• Food Science and Preservation
• /
• v.16 no.2
• /
• pp.286-291
• /
• 2009

Microorganisms in seafood cooking drips were counted and identified. Total viable cell counts were 6.40 and 3.10 log CFU/g in cooking drips of Hizikia fusiformis and Thunnus thynnus, respectively. However, microbial populations fell with increased irradiation doses. In H. fusiformis cooking drips, a 5-log reduction in total aerobic bacteria was obtained by irradiation with 5 kGy. In T. thynnus cooking drips, however, contaminating microorganisms were more resistant to gamma irradiation and only a 1-log reduction was seen. DNA sequence analysis showed that the principal contaminating microorganisms in H. fusiformis and T. thynnus cooking drips were Lactobacillus and Bacillus species, respectively. Therefore, the high irradiation resistance of T. thynnus cooking drips microbes may result from spore formation by Bacillus species.

• Korean Journal of Food Science and Technology
• /
• v.31 no.6
• /
• pp.1619-1627
• /
• 1999

Microbiological characteristics of gamma irradiated low salt squid Jeot-gal were examined. Following the fermentation periods, total bacterial cell, Lactobacillus spp., Staphylococcus spp., Streptococcus spp., Pseudomonas spp. and yeast cell number were counted on their selective media and some acid forming bacteria and Pseudomonas spp. were identified. As the gamma irradiation dose increased, the microbial density of early fermentation phase was reduced and the growth rate was delayed. The repression effects on microbiological growth by gamma irradiation were to be higher as salt concentration increased. Adequate conditions of salt concentration and gamma irradiation for low-salt squid Jeot-gal preparation were 10% and 10 kGy, respectively. Lactobacillus sp. 2, Micrococcus varians and Streptococcus sp. I were isolated from 5% salt containing squid Jeot-gal, and Micrococcus morrhuae was from 20% only while Lactobacillus plantarum and Lactobacillus brevis were widespread. Lactobacillus brevis, Pediococcus halophilus and Pseudomonas diminuta were sensitive and Lactobacillus plantarum, Micrococcus morrhuae and Pseudomonas sp. 3 were resistant to gamma irradiation. The diversity of microflora decreased as salt concentration decreased and gamma irradiation dose increased.

• Journal of Species Research
• /
• v.9 no.2
• /
• pp.85-104
• /
• 2020

In 2019, after a comprehensive investigation of indigenous prokaryotic species in Korea, a total of 12 bacterial strains assigned to the phylum Proteobacteria were isolated from soil. With the high 16S rRNA gene sequence similarity (>98.8%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to independent, predefined bacterial species. This study identified two species in the family Burkholderiaceae, one species in the family Comamonadaceae, two species in the family Oxalobacteraceae, one species in the family Micrococcaceae, one species in the family Bradyrhizobiaceae, one species in the family Methylobacteriaceae, one species in the family Rhizobiaceae, one species in the family Rhodocyclaceae, and one species in the family Sphingomonadaceae. There is no official report about these 12 species in Korea, so are described as unreported bacterial species in Korea in this study. Gram reaction, basic biochemical characteristics, colony, and cell morphology are also described in the species description section.

• Journal of Animal Science and Technology
• /
• v.49 no.4
• /
• pp.515-522
• /
• 2007

To develop the manufacturing method of ice cream with microbiologically safe and proper sensory quality using irradiation for sensitive consumer, 3 different flavors, which were resistant to their flavors against irradiation, were selected and used for ice cream manufacturing to reduce the irradiation-induced off-flavor problem. The general composition was not different among treatments. Total aerobic bacteria were detected as 2.38, 1.23, 1.38, and 1.15 log CFU/g level in ice cream with control(no flavor added), spearmint, mint, and citrus flavor, respectively. No viable cells were observed by irradiation at 1 kGy except for the control. Sensory evaluation indicated that the irradiated ice cream with spearmint flavor at 1 kGy and citrus flavor at 3 kGy had higher overall acceptability. Therefore, a low dose irradiation (less than 3 kGy) with mint or citrus flavors may enhance the safety of ice cream with proper sensory quality for sensitive consumer.