Recently, traditional vegetables and fruits cultivated locally have been increasingly attracting the public’s attention, due to their superior palatability and health functions compared to vegetables and fruits commonly consumed in daily life. Some polyphenols are known to have preventative effects against many diseases and to influence the palatability and quality of foods. Thus, the characteristics of polyphenols contained in traditional vegetables and fruits grown mainly in Yamagata Prefecture were determined in relation to their health functions and food preferences. Major flavonoids identified in the petals of edible chrysanthemum flowers (Chrysanthemum×morifolium Ramat. forma esculentum Makino, cv Kotobuki) showed radical scavenging activities and liver injury-ameliorating effects, which were dependent on the chemical structure. Luteolin and luteolin 7-O-(6"-O-malonyl)-glucoside exhibited stronger radical scavenging activity than the other identified flavonoids. Pretreatment (oral administration) with luteolin or luteolin 7-O-(6"-O-malonyl)-glucoside strongly suppressed carbon tetrachloride (intraperitoneal injection) induced liver injury (increases in plasma aspartate aminotransferase and alanine aminotransferase activities) in mice. Main anthocyanins in 6 sweet cherry (Prunus avium L.) cultivars were identified and quantified to determine the relationship between anthocyanin and flavonoid (rutin) content with identical sugar moiety. Cyanidin 3-O-rutinoside, identified as a major anthocyanin in Japanese cherry cv Benisayaka, could be absorbed from the gastro-intestinal tract when orally administered with a malic acid solution, suggesting that the absorbed anthocyanins might be closely related to their physiological functions. It was also suggested that powdered Japanese cherry, which can be prepared from Japanese cherry juice by food processing, could be available as a raw material for cosmetics.

We used spectrophotometric and image analyses of squashed cooked rice grains to evaluate staling of cooked rice during storage. After storage at 4°C for 0-48 h, individual grains of cooked rice were squashed to 0.1 mm thickness between the cover and slide glass. Brightness (L^*) of the squashed cooked rice grains was measured by reflectance spectroscopy, and image analysis of the squashed cooked rice grains photographed using transmitted light microscopy was performed. Furthermore, measurement of physical properties and sensory evaluation of cooked rice were performed. L^* of squashed cooked rice grains was high at a high amylose content, which increased with storage time. The shape of luminance histograms of gray-scale images photographed using a microscope differed among the rice varieties, and the proportion of low luminance increased with time. It was suggested that changes in the shape of histograms were related to the degree of staling. Ratio of White Area_α130, which was calculated from the ratio of the area of gray value 130 or less in a gray-scale image, and L^* were highly correlated with the physical properties of cooked rice and the staling score determined by sensory evaluation. Therefore, L^* of squashed cooked rice grains and Ratio of White Area_α130 by image analysis suggested that this novel method is useful to evaluate staling of cooked rice.

Metabolomic analysis is emerging as a promising method for the quality assessment of food products. This method provides an objective description of the condition of the target sample by conducting a comprehensive analysis of its metabolites. It is a potentially useful method for the quantitative assessment of compositional changes that occur during food preparation and processing of fresh produce, such as citrus fruit. In this study, lemons, a specialty local product of Hiroshima Prefecture, were used to determine the effect of heat processing on the composition profile of lemon juice. The investigation was conducted using gas chromatography/mass spectrometry analysis. The results indicated a statistically significant change in the constituent profile of lemon juice following heat processing. These changes were attributed to varietal differences, temperature and time. Heating resulted in increases as well as decreases of various compounds. In particular, arabinose was found to be an effective marker for high temperature heat treatment.

Foodborne bacterial pathogens continue to pose a serious threat to public health and represent an economic burden in developed countries. These pathogens encounter many environmental stresses during food production, processing, storage, and distribution. Exposure to stress can induce various degrees of cellular injury depending on stress intensity and the physiological state of individual cells within the population. The injured cells may enter a non-culturable physiological state, in which the cells remain metabolically active, retain their pathogenic properties, and possess the ability to resuscitate under favorable conditions. These cells do not grow in conventional pre-enrichment media used for the detection of pathogenic bacteria in food and environmental samples, and may therefore go undetected during routine monitoring. These cells are presumed to be a significant potential risk for foodborne diseases. Thus, elucidating the molecular mechanisms underlying the induction and action of stress responses as well as resuscitation of the injured cells is essential for the development and implementation of more effective control measures. Moreover, such research will ultimately lead to more effective design and sequencing of processing steps, thereby preserving the nutritive value of food while ensuring maximum safety for the consumer.

The control of food poisoning associated with fish and fish products is challenging, even in the developed world. Injured cells of bacterial pathogens, generated by various stressors during food processing, are considered to be an important risk factor in food poisoning incidents. It is important to accumulate more knowledge on the physiology, genetics, and molecular biology of injured bacterial cells related to fish and fish products, and also to apply this knowledge to the development of new technologies. Here, we introduce recent advances in the physiology and genetics of Vibrio parahaemolyticus and Listeria monocytogenes and discuss future directions of the risk control of pathogens in fisheries.

Currently, injury of foodborne pathogen in agricultural environment is unclear. So, we observed survival of foodborne pathogens on common procedure for growing vegetable by cultivation on two types of agar medium that possess different selectivity. In case of Salmonella enterica serovar Infantis (SI) on the process of manure preparation, injury was estimated by cultivation on selective agar medium and resuscitation on non-selective agar medium. While in Listeria monocytogenes (LM) on cultivation environment of tomato, physiological changes were confirmed by salt content in agar medium. In manure environment, insufficient elevation of temperature in piled feedstock caused injured SI. LM survived for long term and part of these survived as injured LM in soil and on the surface of tomato fruits. It might be possible to estimate injured SI in actual condition of manure preparation by above procedure. On the contrary, there are practical difficulties for discriminating injured LM in actual agricultural environment by only salt sensitivity.