• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.648-652
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• 2003

Precise and rapid method out for distinguishing blended sesame oils through the electronic nose analysis was developed. Sesame oil was blended with corn oil at the ratio of 95 : 5, 90: 10, and 80 : 20 (w/w), respectively. Samples were then analyzed by gas chromatography, SPME-GC/MS, and the electronic nose composed of 12 different metal oxide sensors. Sensitivities $(delta\;R_{gas}/R_{air})$ of sensors from electronic nose were analyzed by principal component analysis (PCA). Proportion of the first principal component was 98.76%.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.185-189
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• 2010

An electronic nose was used to identify Salmonella contamination on beef based on odors. To detect pathogen contamination of beef, $100{\mu}L$ of $10^5CFU/g$ Salmonella Enteritidis or Salmonella Typhimurium cell suspensions were spiked onto 5 g beef sirloin samples in individual vials. Odor changes over time were then measured and analyzed using an electronic nose system to identify pathogen contamination. In principle, the electronic nose system based on a surface acoustic wave (SAW) detector produced different frequency responses depending on the time and amount of each chemical. Multivariate analysis of the odor data was conducted to detect Salmonella contamination of beef. Salmonella odors were successfully distinguished from uncontaminated beef odors by principal component analysis (PCA). The PCA results showed that Salmonella contamination of beef could be detected after 4 h of incubation. The numbers of cells enumerated by standard plate count after 4 h of inoculation were $2{\times}10^6CFU/g$ for both Salmonella Enteritidis and Salmonella Typhimurium.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.437-439
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• 2005

Freshness of stored soybean curd as sensitivity ($R_{gas}/R_{air}$) was evaluated at 48-50 hr intervals using electronic nose at regular sequential square-wave temperatures between $4\;-\;10^{\circ}C$. Obtained kinetic data from apparent first principal component score $(PC1)_{app}$ and storage time were used for prediction of freshness. Percentage difference between predicted and actual values of stored soybean curd was less than 8.9% under fluctuating temperature condition.

• Journal of Biosystems Engineering
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• v.33 no.5
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• pp.333-339
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• 2008

The purpose of this study was to develop a portable electronic nose system to measure volatile components of agricultural and food products. Also, a graphical operating software to control the electronic nose system and to acquire signals through the Internet was developed. An array of five commercial metal oxide gas sensors was used to detect various volatile gas components of target samples. Transient and steady state signals were analyzed to extract variables related to sample states, To find optimal operating conditions of the system, several experiments were performed with different gas chambers, vacuum pumps, gas sampling temperatures, and sample container sizes. The patterns of gas sensor signals were analysed to find effects of the various conditions.

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.237-242
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• 2006

The pattern of volatile emissions from white ginseng powders (WGP) that were treated with selected preservatives was investigated during 5-months of storage (at -10 and $25^{\circ}C$) by an electronic nose system equipped with 12 metal-oxide sensors. WGP were treated with gamma radiation at 5 kGy, commercial methyl bromide (MeBr), and phosphine fumigations. Electronic nose differentiated the volatile patterns of the WGP with each different preservative treatment. In addition, each volatile pattern was affected by both storage time (1, 2 and 5 months) and temperature (-10 and $25^{\circ}C$). After 5-months of storage, the least change of volatile patterns was observed from WGP fumigated with phosphine at $-10^{\circ}C$. The result also showed that volatile changes in WGP were much more affected by storage time than by storage temperature.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.856-860
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• 2005

Electronic-nose system was used to discriminate commercial sesame oils (A-F) extracted from imported seeds. Response (delta $R_{gas}/R_{air}$) of sensors gained from electronic nose was analyzed by principal component analysis (PCA). Flavor pattern of sesame oil A was similar to those of sesame oils B, C, and D. Sesame oils blended with corn oil at the ratio of 95:5, 90:10 and 80:20% (sesame oil/corn oil, w/w) could be discriminated from ouch genuine sesame oil.

• Journal of Biosystems Engineering
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• v.29 no.4
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• pp.317-322
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• 2004

This study was conducted to evaluate the feasibility of identifying freshness of beef using a surface acoustic wave (SAW) sensor based electronic nose. The beef was stored at 5$^{\circ}C$ and aroma was measured with the passage of time. Chromatographic analysis of the odor showed that number of volatile components and their amounts were rapidly increased after 19 days of storage. Classifying beefs according to their storage days was possible using principle component analysis (PCA). Classifying beefs processed from four different origins was also possible with PCA analysis of odor. This study shows that electronic nose can be applied to beef freshness evaluation and classification of its origin.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.117-121
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• 2016

The objective of this study was to analyze the flavor patterns of commercial Korean distilled spirits using a mass spectrometry-based electronic nose and an electronic tongue. Thirteen types of domestic distilled spirits were used for analysis. The flavor patterns of the distilled spirits were clearly identified through discriminant function analysis of the raw materials. The obtained data of the electronic nose analysis showed that the flavor pattern of the distilled spirits aged in oak barrels was not significantly different from that of the general distilled spirits. According to the results of the electronic tongue, the distilled spirits made with rice had a stronger flavor than those made with foxtail millet. Compared to the sensitivity value of each taste sensor, the distilled spirits showed various intensities of sourness and umami. Therefore, an electronic nose and electronic tongue could be successfully used for quality evaluation and new product development of distilled spirits.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.193-200
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• 2016

The purpose of this study was to investigate whether the electronic nose can be applied as a primary screening procedure to detect ethanol in gochujang for halal certification. First, ethanol content in 25 traditional gochujang was measured by gas chromatography with flame ion detector, widely accepted as the conventional method of alcohol detection. The content ranged from 0.14 to 2.7%. Then, 8 gochujangs selected from among the initial 25 samples were analyzed by electronic nose. Similar ethanol content patterns were observed between the two detection methods. In addition, commercial gochujang products were examined by electronic nose to ensure that they complied with the required ethanol standard of the halal certification authority. Consequently, it was confirmed that electronic nose analysis can be applied as a primary screening method for halal certification.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.356-362
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• 1998

The study is to predict fermentation time of Korean style soybean paste by portable electronic nose that has six metal oxide sensors. Korean style soybean paste using Aspergillus oryzae was fermented at $15^{\circ}C,\;20^{\circ}C\;and\;25^{\circ}C$. The changes of sensitivity by electronic nose, amino nitrogen and reducing sugar were observed during fermentation. Sensitivities of six metal oxide sensor were decreased with increase of fermentation time while amino nitrogen was increased. Sensor #3 and #4 showed good correlation between sensitivities of the sensors and fermentation time $(r^2=0.71{\sim}0.95)$. And the good correlation between sensitivity by electronic nose and the produced amino nitrogen was shown until soybean paste was fermented. Portable electronic nose using metal oxide sensor (#3 and #4) could predict fermentation time of Korean style soybean paste.