Recently Japanese people have had many food problems, such as Chinese vegetables with pesticide residues, BSE, E. coli O-157 contamination, hidden source of origin and false labeling. So the Food Safety Commission of Japan and the Consumer Affairs Agency of the Government of Japan have been established. But some fears about foods have not gone away. Many Japanese people still are distrustful of foods and politics. Especially the consumer has fears about pesticide residues and food additives. After the accident at Fukushima atomic power plant, the consumer feels strong anxiety about our daily foods which are polluted with radioactive compounds. With this social background, it is true that many food dealers have serious problems which we call food off-flavors in Japan.
Therefore our colleague thought that we needed an organization in which off-flavor problems were discussed. In July 2011 we established the Food Off-Flavor Study Group (FOFSG), and the first meeting on food off-flavor studies was held at Tokyo Kasei University. This group was approved as a general incorporated association this June. The aim of FOFSG is to make a place where we discuss off-flavor problems and to share that information, so that we contribute to improving the quality of Japanese food.

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In Japan, the problem of mustiness caused by 2,4,6-trichloroanisole (TCA) was first encountered in 1976, 10 years after Engel published a report that a stale mouldy odor and taste had been “detected in chicken meat and eggs.” At the time, the food industry as well as packaging companies experienced a serious mustiness problem and suffered major disruptions. Our company also encountered severe contamination in its products, mainly in its alcoholic beverages. These issues required over a year to resolve, for several reasons. The odor detection limit for TCA is extremely low, at 1 ppt; consequently, trace amounts were below the limit of detection with the analytical devices and techniques available at the time. Furthermore, since there were almost no previous reports on such a mustiness problem, it was necessary to start by synthesizing standard substances and carrying out a wide array of repeated experiments through trial and error. Based on this experience, the present paper introduces mechanisms by which contamination with TCA causes mustiness, and proposes measures to tackle the problem.

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In this paper, a simple and precise analytical method for detection of off-flavors with GC/MS is described. Off-flavors were extracted from various foodstuffs by using Solid Phase Micro Extraction (SPME), Stir Bar Sorptive Extraction (SBSE) or Adsorbing Tube. The extracted chemicals were injected into a GC/MS and analyzed under a unified analytical condition. Each chemical detected was identified by its retention time and mass spectrum. Retention time obtained was converted into retention index. After this process, the result was registered into the chemical database with other chemical information, e.g. chemical name, molecular weight, molecular formula, and CAS registered number. Total number of chemicals listed in the database is 1004, which includes 274 off-flavors, 17 organic solvents, 196 environmental contaminants, 470 pesticides residues and 47 highly toxic substances. The combination of the unified analytical method and the database mentioned above was very useful to identify causative agents of off-flavor.
Two quantitative methods of off-flavor are also described. These are based on the manner of adding the standard substance at several concentration levels in the control samples which did not contain the target substance.
In the last section, three examples of off-flavors from foodstuffs or food packages are reported. In those cases causative agents such as 2,4-decadienal, mineral oil and 1,4-dichlorobenzene were identified by the reported method.

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Off-flavor problems can occur anytime when dealing with foodstuffs, although it should not happen under normal conditions. When facing with such a problem without any prior preparation or experience, it is natural that one might hesitate in deciding how to best proceed. However, analytical methods should be essentially the same as those applied for flavor analysis in general; the biggest differences are the limited amounts of samples available and the time allowed to obtain answers. In this article, based on the author's experience, a universal method for off-flavor analysis is discussed, focusing mainly on effective performance without using special or expensive apparatus/equipment.
For preparing analytical samples from off-flavor foods, vacuum hydro-distillation of the food itself, or extract/ aqueous suspensions is recommended, followed by extraction with low-boiling organic solvent. Extracts can be concentrated under atmospheric pressure after drying over an appropriate desiccant salt to the desired volume. For off-flavor analysis, the only guide is the “off-flavor” itself. Comparison of the off-flavor sample with normal sample(s) should provide clues, both in instrumental and sensory analyses.
When facing difficulties to find dedicated GC-O (GC-Olfactometry) equipment, an alternative GC-O method may be chosen with olfactory assessment at the FID port on GC using a home-made glass nozzle. While this method is not perfect, it does allow useful information to be obtained.

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The brewing process consists of four steps: mashing, boiling, fermentation and maturation. Here is described information for the control of off-flavor at each step. Several studies have shown how to decrease off-flavor in the brewing process. Several off-flavors are known in beer such as (E)-2-nonenal which yields a cardboard flavor after bottling and canning, hydrogen sulfide during the fermentation process, diacetyl (vicinal diketone) during maturation, 3-methyl-2-butene-1-thiol which yields a sunlight odor after bottling and so on. These off-flavors are described in the brewing process and how to control them by their mechanism, threshold and methods for analysis. It is possible to supply good taste to the consumers by their control.

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Off-flavors can be introduced to foodstuffs mainly in three stages, in producing raw materials, in manufacturing the product and during distribution. This paper provides typical cases off-flavor examples in each step. First, one case in spaghetti proved to be due to coumarin contamination in wheat fields. Next, 2-MIB off-flavor in chestnuts was caused in manufacturing processes. Finally, handling in the distribution stage was blamed in the case of p-DCB off-flavor in noodles. Understanding these cases, it is important to apply the knowledge to prevent other cases of off-flavor from occurring. Moreover, studies of off-flavors provide us with opportunities to improve quality of products and therefore consumer satisfaction.

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Menopause is a natural process in a woman's life, marking the transition from the reproductive to the non-reproductive years. Role in life , hormonal and family structure changes all pose challenges in midlife. The changes each woman faces are as individual as her own environment and the particular cultural context. In the climacteric phase, perimenopausal women may suffer many symptoms that may interfere with their quality of life. There have been many studies about medical management and treatment of menopausal symptoms (i.e. hormone replacement therapy). However, there are only few reports about dietary habits and eating behavior of perimenopausal women.
This article reviews our studies on nutrition intake in perimenopausal women with climacteric disorder and associated stress. Dietary balance in such women may not be optimal, with alteration in habits due to stress (i.e. dietary restraint or excess). Social capital is a trait that appears to affect health. In our study, women with rich social capital group reported better dietary habits in comparison with the poor social capital group. Population approaches focusing on social capital may be very effective for improving health in the very important perimenopausal period and contribute to successful aging. It is hoped that more evidence can be generated about dietary intake, associated behavior and nutrition management, to provide better nutrition education for health of perimenopausal women.

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Plants absorb carbon dioxide from the air and water with their roots, and produce oxygen and sugar by photosynthesis in the chloroplasts using light energy from the sun. This oxygen is necessary for breathing by humans, and the sugar supports human life and activity as the basic ingredient of food. In other words, plants are a necessity which cannot by lacking as a food resource for humans, and agricultural production is the origin of food for humans. In a plant system, the fruits and vegetables are classified by the shape and structure of the flower, and flowers are also sold along with vegetables for their edible parts. There are 150 types of vegetables which we can obtain in a market, and 50 types of fruit. One person consumes 100 kg of vegetables and 40 kg of fruits as food a year. There are a large number of varieties for each vegetable and fruit. Tomato and eggplant have approximately 120 varieties, while grape and citrus fruits have 100 varieties. The varieties of fruits and vegetables that consumers prefer are distributed in the market. In recent years, traditional vegetables that are unique to the area have become popular. These various vegetables and fruits make our eating habits varied and rich.

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This article is the second in a series of publications entitled “How to Study Dietary Culture”. The author proposes to categorize the factors affecting dietary culture into three categories. They are 1) Natural environment: geographical and meteorological conditions related to food resource production, 2) Human technology: acquisition, preservation, preparation and distribution of resources and foods, 3) Social rule: normative rule and customs of dietary behavior.
By analyzing dietary behavior through these three lenses mentioned above, it is possible to have a more scientific approach and perspective regarding the establishment of certain dietary behaviors, rather than simply summarizing as dietary culture.

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