• Journal of Food Hygiene and Safety
• /
• v.31 no.3
• /
• pp.222-225
• /
• 2016

In this study, the performance of five selective media for coliform bacteria was evaluated. In total, 83 coliform isolates from ready-to-eat food and 21 reference strains were inoculated in five agar media : Chromocult coliform agar (Merck Millipore), HiCrome coliform agar (Sigma), CHROMagar ECC chromogenic media, Brilliance E. coli/coliform selective agar (OXOID), and endo agar (Merck Millipore). Coliform isolates and reference strains were inoculated on the selective media to test media sensitivity and specificity. The tested media showed the following sensitivities for the isolated strains: Chromocult coliforms agar and HiCrome coliform agar, 94%; Brilliance E. coli/coliform selective agar, 93%; CHROMagar ECC chromogenic media, 92%; and endo agar, 74%. In addition, all media showed 100% specificity, except for endo agar (71%). Moreover Chromocult coliform agar and HICrome coliform agar showed high levels recovery. Taken together, these results identified Chromocult coliform agar and HICrome coliform agar as an effective selective medium for coliforms with higher sensitivity and specificity compared to other media tested in this study.

• Korean Journal of Environmental Biology
• /
• v.17 no.3
• /
• pp.315-319
• /
• 1999

Spore attachment of Ulva fasciata on agar and agaroses coating films showed various surfaces properties according to concentrations of agar or agaroses or via methanol. The highest number of spore attachment occurred in Sigma agarose coating film. Spore attachment on Bacto agar and other agaroses coating films showed the 12 ∼ 36 times less than Sigma agarose coated film. Comparison of spore attachment on 2.5% and 5％ Seakem agarose and Bacto agar coating films differed in two concentrations while coating of 2.5% and 5％ with NuSieve and Sigma agaroses did not differed. Spore attachment of coating made of 5％ and 5% via 4% MeOH with Bacto agar and Nusieve agarose only differed. Overall, these results indicated agar and agarose coating films differed in spore attachment. Results of this work will be useful baseline for bioassay of antifouling activity of fouling organisms.

• Mycobiology
• /
• v.33 no.4
• /
• pp.215-222
• /
• 2005

Variability in growth and sporulation of five isolates of Arthrobotrys dactyloides was studied on five agar, 6 bran and 5 grain media. Potato dextrose agar (PDA) supported maximum growth of isolate A, C and E, while growth of isolate Band D was significantly lower on this medium. On Czapek's agar and yeast glucose agar media the differentiation in the isolates in relation to growth was poor than PDA. The other two media showed much poorer differentiation. On Czapek's agar medium, sporulation was recorded in isolate B only, whereas other isolates showed rare sporulation. Among the bran media, pea bran agar medium supported maximum growth of all the isolates except isolate B. Gram and rice bran agar media were next best. However, the growth of isolate B on the gram bran agar medium was more or less equal as other isolates. On pigeon pea bran agar medium, isolate E failed to grow while other isolates recorded poor growth. On lentil bran agar medium, only isolate Band D recorded little growth, whereas other isolates failed to grow. All the isolates recorded good sporulation on bran agar media except pigeon pea and lentil bran agar media. The grain agar media supported moderate to very good growth of all the isolates. In general isolate B remained slow growing on these media except gram grain and sorghum grain agar media on which growth of this isolate was comparable to other isolates. Sporulation in general, was good on all the grain agar media. Among different substrates screened, barley grain and pea bran were found superior to others for mass culture of isolate A of A. dactyloides.

• The Korean Journal of Food And Nutrition
• /
• v.10 no.2
• /
• pp.228-233
• /
• 1997

The effects of spray drying and extrusion drying on functional properties of agar were investigated to increase the availability of agar in food industry. In case of unmodified and spray-dried agar, gel strength and viscosity were 1,070g/$ extrm{cm}^2$ and 170.50pcs, 820g/$\textrm{cm}^2$ and 17.07cps, respectively, while 523.28g/$\textrm{cm}^2$ and 12.81 in extrusion-dried product. The lowest dissolving onset and conclusion temperature were revealed in extrusion sample, where it was attained in 80 and 11$0^{\circ}C$ of unmodified, 60 and 9$0^{\circ}C$ of spray-dried, and 35 and 8$0^{\circ}C$ of extrusion-dried agar, respectively. Melting and setting in unmodified sample were showed to 110.17 and 40.52, 90.05 and 39.54$^{\circ}C$ in spray dried, and 80.01 and 36.05$^{\circ}C$ in extrusion-dried agar, respectively.

• Archives of Metallurgy and Materials
• /
• v.64 no.3
• /
• pp.851-855
• /
• 2019

In this study, agar-based nanocomposite films containing ultra-porous silica aerogel particles were fabricated by gel casting using an aqueous agar/silica aerogel slurry. The silica aerogel particles did not show significant agglomeration and were homogeneously distributed in the agar matrix. Transmission electron microscopy observations demonstrated that the silica aerogel particles had a mesoporous microstructure and their pores were not incorporated into the agar polymer molecules. The thermal conductivities of the agar and agar/5 wt.% silica aerogel nanocomposite films were 0.36 and 0.20 W·m^-1·K^-1, respectively. The transmittance of the agar films did not decrease upon the addition of silica aerogel particles into them. This can be attributed to the anti-reflection effect of silica aerogel particles.

• Korean Journal of Human Ecology
• /
• v.8 no.1
• /
• pp.33-48
• /
• 2005

The purpose of this is to agar powder addition to retard retragradation for making Backsulgi. Backsulgi is manufactured promptly by adding ingredients having agar powder and then observation of sensory and texture characteristics. Then Backsulgi determinded in storing at the temperatures of 20 and Celsius degrees for 0, 24, 48 and 72 hours, respectively. The results from this study are as follow; 1. Moisture absorption of control show 34.4%, compared with, Backsulgi with agar powder added 3%, 6%, 9%, 12%, 15% show higher 37.03%, 39.28%, 41.72%, 43.5%, 44.70%, respectively. 2. In terms of chromaticity, lightness of control show $70.68{\pm}7.248{\sim}61.25{\pm}0.90$, the longer time is and much agar powder Backsulgi show lower and 15% agar powder added Backsulgi show $51.53{\pm}0.921{\sim}54.715$. Then redness(a) of control show $-0.70{\pm}0.14$, compared with 15% agar powder added Backsulgi show $-0.32{\pm}0.047$. 15% agar powder Backsulgi show $9.03{\pm}0.313$ higher in yellowness than control $5.47{\pm}0.40$. 3. Control and agar powder Backsulgi was shown pH 6.1~6.3, the longer time is, all Backsulgi was shown pH 5.5~5.9 and much agar powder Backsulgi was shown an weakly acidity. 4. Swelling and pore ratio of control was shown 85.36% and 118.32%, compared with, agar powder added Backsulgi was higher a rate of increase. 5. For a sensory evaluation, the longer time is, adding agar powder rice cake is more perfected at 20$^{\circ}C$ in times if smooth, inner moisture, chewiness, after selling, overall quality. 6. Determination of texture characteristics by a reometer shows that Backsulgi with agar powder added change more in hardness that controls, indicating that effect of retarding retrogadation is higher when storage time is longer. 7. The correlation of hardness, springness between sensory and instrumental evaluation showed significantly positive function.

• Journal of Life Science
• /
• v.22 no.2
• /
• pp.259-265
• /
• 2012

A bacterial strain, CK214, exhibiting high motility on an LB agar (1.5%, w/v) surface was isolated from the environment. The formation of unusual agar shrinking around colonies on agar plates was observed. The strain grew on minimal media containing pure agar as a sole carbon source. The cell-free culture supernatant of CK214 generated a reduced form of sugar in the in vitro reaction with the use of pure agar as a substrate, suggesting the secretion of an agar-degrading enzyme. The CK214 strain showed swarming motility on the solid media containing a wide range of concentrations of agar (0.5, 1.0, 1.5, 2.0% w/v). Various tests, including Gram staining, API analysis, and phylogenetic analysis based on 16S rDNA sequences identified that the CK214 strain was a G(+) rod-shaped bacterium grouped in genus Paenibacillus. Electron microscopic analysis demonstrated that the P. CK214 strain is peritrichously flagellated. Through transposon random mutagenesis, several agar-degrading activity defective mutants (ADMs) were generated. These mutants will be used in the future experimentation for the study of the correlation between agar-degrading activity and motility.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.10
• /
• pp.1685-1688
• /
• 2004

This study mechanically measured physical properties of jelly made by adding kappa carrageenan and agar-agar to the sipjeondaebo extract, varying the addition ratio. The sipjeondaebo extract used in the study showed 4.95 pH, 7.0 Brix$^{\circ}$, and high turbidity of more than 3.0 NTU. The sugar content was fixed at 25.2 Brix$^{\circ}$ when isomaltooligosaccharide was added in a 25-percent concentration. When the jelly was mechanically measured after it became hard in the refrigerator, the measurement results did not show any significant difference in cohesiveness between different addition ratios of agar-agar to kappa carrageenan. In the measurement of chewiness and gumminess, the jelly show a significantly decreasing tendency in both the two properties as the increase in the addition rate of agar-agar was made. Hardness was also measured lower as the more addition of agar-agar was made, and its the highest level was shown when there was the addition of kappa carrageenan only. Springiness was the highest when the ratio of kappa carrageenan to agar-agar was 0.7%:0.3%, while it was measured the lowest when agar-agar was added in a 1.0% concentration. In the measurement of the jelly's physical properties, the results showed the highest level of appearance when the ratio of kappa carrageenan to agar-agar was 0.7% but indicated that there was no significant difference in flavor. The overall Quality was evaluated to maintain the highest level at the kappa carrageenan to agar-agar ratio of 0.7%:0.3%, followed by a 0.5%:0.5% addition ratio.

• Korean Journal of Microbiology
• /
• v.52 no.1
• /
• pp.25-31
• /
• 2016

An enterococci selective medium was developed to detect the presence of enterococci for use as a fecal contamination indicator. Among several media which have been known to detect enterococci, the following 9 different kinds of media were selected: Enterococci Confirmatory agar, Azide dextrose agar, Bromocresol-purple azide agar, Esculin bile agar, Citrate azide tween carbonate agar, KF Streptococcus agar, BROLACIN agar, Kanamycin esculin azide agar, and Membrane filter Enterococcus selective agar. Various components from the nine media were mixed to develop a more effective enterococcus selective medium. The newly developed medium named as 'Enterococcus Mixed medium' was more effective than the previous 9 media. Enterococci strains (Enterococcus avium KACC 10788, Enterococcus faecium KACC 11954, Enterococcus saccharolyticus KACC 10783, Enterococcus durans KACC 10787, Enterococcus faecalis KACC 11304, and Enterococcus hirae KACC 10779) and non-enterococci strains (Escherichia coli KACC 10005, Staphylococcus aureus subsp. aureus KACC 10768, and Bacillus subtilis KACC 10111) were used to test the new medium. As a result, the enterococci strains grew well on the Enterococcus Mixed medium whereas the non-enterococci strains did not grow well on it. Additionally, growth of enterococci with freshwater and seawater samples was observed to be good on the Enterococcus Mixed medium. The result of this study confirmed that the Enterococcus Mixed medium was effective in detecting the target enterococci.

• Korean journal of food and cookery science
• /
• v.29 no.6
• /
• pp.761-768
• /
• 2013

Healthy ginseng pudding was made with different doses of two gelling agents and stored at $37^{\circ}C$ for eight weeks. And then quality characteristics and palatability were measured. Sweetness and pH level increased in newly made ginseng puddings but decreased during storage. Acid taste decreased but increased during storage in A (pectin 0.2%+agar 0.6%). But it increased but subsequently decreased in B (agar 0.8%). Acidity in C (agar 1%) remained unchanged until six weeks but slightly increased at 8 weeks of storage. Texture increased in all specimens but subsequently decreased. Chromaticity value of L decreased in all specimens before increasing while the values of a and b increased and subsequently decreased. In texture examination, hardness and adhesion were higher in C (agar 1%) and lower in A (pectin 0.2%+agar 0.6%). There were no differences in elasticity among three specimens. Cohesion was higher in C (agar 1%) while it showed a similar level in A (pectin 0.2%+agar 0.6%) and B(agar 0.8%). Stickiness and chewiness were higher in C(agar 1%) but lower in A(Pectin 0.2%+agar 0.6%), compared with C(agar 1%) specimen. In sensory test, overall palatability was higher in A (Pectin 0.2%+agar 0.6%). In conclusion, ginseng pudding with 0.6% agar and 0.2% pectin exhibited better quality. And ginseng pudding has potential to be developed as healthy dessert considering ample physiological and functional properties.