There are two evaluation methods of odor evaluation, roughly classified into static evaluation and dynamic evaluation. However, a multicomponent simultaneous dynamic evaluation method that combines both evaluation methods is required. We have investigated a simultaneous dynamic evaluation method of multicomponent using mass spectrometer by ambient ionization technique. As a result of the investigation, volatile compounds were stably detected by using a volatile compound introducing device in combination. It was also possible to improve detection sensitivity. When this method was used to measure the smell of foods, data it could be supported the sensory evaluation was obtained.

Flavor-releasing phenomena have gained much attention recently due to an increasing demand to correlate the results of instrumental analyses and sensory evaluations. It is difficult to measure volatile compounds in foods within seconds and evaluate them using gas chromatography. We introduce the instant quantification of flavor release, using a direct analysis mass spectrometer system and focusing on spices in prepared foods, and a new analytical approach to flavor release data using this system.

Homogenization is one of the most important processes for producing dairy beverages. The effects of homogenization pressure on sensory characteristics, preference and retronasal-aroma release of flavored dairy beverages were investigated by sensory evaluation and gas chromatography-mass spectrometry (GC-MS) analysis using a retronasal aroma simulator (RAS). The results showed that homogenization pressure affected significantly on sensory characteristics, preference and retronasal-aroma release of flavored dairy beverages.

Retronasal aroma is one of the most important factors for food palatability. Generation of retronasal aroma depends on the dynamic process of bolus formation, such as food breakdown and mixing with saliva. It is also influenced by inter-subject variability. Aroma simulators are useful for obtaining data concerning retronasal aroma release phenomena, and some of the apparatuses reported so far are introduced in chronological order. The first one, which was reported in 1986, was devised simply by agitating vials and then began to have a powerful motor for compressing the food controlled by the computer.

In recent years, complaints of cooking odor, which is a small-scale source, are increasing, but it is extremely difficult to deal with this complaint. Therefore, with regard to grilled meat odor and curry odor, water spray treatment, activated carbon treatment, normal temperature catalyst treatment, the deodorizing performance was investigated. The deodorization efficiency was low with spray water only, and it became clear that the possibility of enhancing the deodorization efficiency by combining activated carbon and normal temperature catalyst. It became clear that the effective deodorization method may be different depending on cooking odor.

We conducted questionnaire surveys and experiments on odor quality evaluation in order to determine the criteria for selecting expressions that properly represent various kinds of odors and allow evaluation with high reproducibility. First, we chose 303 words and conducted questionnaire surveys on their suitability for the evaluation. Then, we performed experiments on odor quality evaluation with 80 odor samples. The result suggested that the difficulty in understanding odor quality representation, general frequency of use, variation in evaluation score, and correlation among evaluation expressions should be considered.

Most of the unpleasant odors in living spaces derive from aldehydes. In addition, formaldehyde is reportedly carcinogenic and a cause of sick house syndrome. However, existing deodorizing methods cannot directly reduce the amounts of aldehydes in living spaces. Therefore, an effective method that reduces aldehyde levels is demanded. To this end, we investigated the aldehyde-removing effect of enzymes from the acetic acid bacterium Gluconacetobacter hansenii, which convert aldehydes into carboxylic acids. Aldehydes were injected into a test space of 1m³, and exposed to an air cleaner containing a suspension of acetic acid bacterial enzymes. The changing aldehyde concentration was measured by high-performance liquid chromatography and thermal detector gas chromatography/mass spectrometry, and the reduction rate of the aldehyde was calculated. Almost all of the aldehydes were clearly reduced and no aldehyde odors remained in the space after the test. The results suggest that aldehydes were directly decomposed by the acetic acid bacterial enzyme suspended in the air cleaner. A novel deodorizing method based on acetic acid bacterial enzymes is expected to be developed for homes and workspaces.