Conventional plate counting with selective agars is time-consuming and labor intensive for the detection and enumeration of microorganisms associated with food-borne illnesses from food and environmental samples. In addition, it may be unsuitable for the rapid estimations required for food sanitation and hygiene. To overcome these technical challenges, a superior method, termed FISHFC (fluorescence in situ hybridization [FISH] in combination with filter cultivation [FC] on a membrane filter), was developed. The FISHFC method has equal detection accuracy to the conventional plate counting method. It enumerates only viable food-borne pathogens from food samples within 8-17 h, which suggests that the accurate evaluation of pathogen contamination can be completed within two working days. Therefore, the FISHFC method with species-specific detection probes contributes to ensuring food safety. This article introduces the rapid enumeration FISHFC method for the estimation of food-borne pathogens.

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To investigate the characteristics and food applicability of Ecklonia stolonifera inhabiting off the coast of Oham, Aomori Prefecture, seasonal changes in carbohydrates (laminaran, alginic acid, and fucoidan), amino acids, and polyphenols were determined between March 2008 and February 2009. Algal size reached the maximum (about 60cm) in June, whereas the minimum size (about 30cm) was noted in November. The laminaran content reached the maximum (about 200mg/g dry weight) in August and decreased thereafter. The minimum content (about 12mg/g dry weight) was noted in March, a 16-fold difference. The alginic acid content did not show a marked seasonal variation, and the content accounted for 20-30% of the dry weight. Fucoidan also showed no marked seasonal variation. Further, the following two types of fucoidan were noted: that containing xylose and mannose at a higher amount, and G-fucoidan. The main amino acids were alanine, aspartic acid, and glutamic acid. The alanine content was particularly high, reaching a maximum of 12mg/g dry weight in May-June and a minimum of 3mg/g dry weight in August-November. The polyphenol content reached the maximum (about 50mg/g dry weight) in November and decreased thereafter. Based on these findings, the timing of collection is important for the optimal use and application of the components of E. stolonifera.

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Both the leaching of potassium and chlorophyll from broccoli and changes in color were examined during soaking in hot water at four temperatures ranging from 70°C to 100°C. To describe the leaching of potassium quantitatively, the measured data were fitted to the sphere diffusion model using a non-linear least squares method. Changes in color and chlorophyll based on the measured data were determined quantitatively by the zero-order and the first-order reaction, respectively. Therefore, the measured results were in approximate agreement with the calculated results. The applicability of microwaving for blanching broccoli was examined. Changes in enzyme (peroxidase) activity, weight, ascorbic acid and color were compared between two blanching methods (microwave radiation and immersion in boiling water). The time required for enzyme inactivation was 50 s in microwave blanching and 90 s in boiling water blanching. Weight loss increased with microwave blanching compared with boiling water blanching, whereas drip and ascorbic acid loss increased in boiling water blanching compared with microwave blanching. Chroma of broccoli showed little difference between microwave blanching and boiling water blanching. These results suggested that microwaving is useful for the blanching of broccoli.

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Phosphate salts are currently used as food additives in processed foods such as surimi to improve gel formation and coloration. Recently, a novel frozen surimi process using sodium citrate was established. However, excessive sodium citrate intake may increase the risk for inhibition of calcium absorption. In this study, we investigated the effects of sodium phosphate (sodium polyphosphate and sodium pyrophosphate) and sodium citrate on active and passive Ca transport using Caco-2 cells. The results revealed that sodium polyphosphate, but not sodium citrate, inhibited passive Ca transport. Moreover, no inhibition or activation of gene expression common to all active Ca passive processes by exposure to sodium phosphates and sodium citrate was observed. In the in vitro digestion, abundant water-soluble Ca was present in the frozen surimi sample containing sodium citrate compared with that containing phosphate salts. The above indicates that the effects of sodium citrate on passive as well as active Ca transport differ from those of sodium phosphate. With sodium citrate, the risk that excessive intake may inhibit calcium absorption has not been observed.

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The effects of agar gel sample size on chewing and swallowing muscle properties were investigated by electromyography and sensory evaluation. Crushed agar gel and cubic agar gels of 3.5mm (3.5mm cubic gel) and 15mm (15mm cubic gel) were used as samples. With the crushed agar gel, the change in activity of the masseter muscle was small, and the strength during mastication did not show a significant difference on sensory evaluation with higher chewing cycles. The activity time of the masseter muscle decreased slowly as the chewing frequency increased. The maximum voltage at 5 to 20 chewing cycles of the masseter muscle was the highest with the 3.5mm cubic gel compared to that with the other samples ; however, the strength during mastication was comparable to that with the 15mm cubic gel on sensory evaluation. The time from the end of mastication to swallowing at 10 to 20 chewing cycles was the longest with the 15mm cubic gel compared to the other samples. The section area of the masseter muscle at 5 chewing cycles was the largest with the 15mm cubic gel than with the other samples, but that and the time from the end of mastication to swallowing decreased remarkably. These results showed that the activity of the masseter muscle was affected by sample size.

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Reuse of the rice bran byproduct of sake brewing was proposed. Koji was prepared using red rice bran. Seed koji was added to steamed red rice bran at a rate of 0.5%, and incubated at 30°C and 90% humidityfor 1-3 days. Next, we obtained a red rice bran koji that exhibited high saccharification ability. The starch in white rice bran was effectively saccharified by the red rice bran koji. When preliminary saccharification for 90 minutes was carried out to secure fluidity of the culture medium, simultaneous saccharification and lactic acid fermentation using Lactobacillus rhamnosus was possible. Consequently, a lactic acid concentration>12g/100ml (99.3% L-lactic acid) was obtained after 72-hour cultivation.

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In the present study, we examined the gastroprotective effects of a dried aqueous extract of peppermint (PE) by using an animal model of stress ulcer and a questionnaire survey of healthy volunteers. In the animal study, a single administration of PE (300mg/kg, p.o.) to mice significantly inhibited gastric lesions induced by forced swimming stress (P<0.01). For the questionnaire survey, healthy volunteers (94 males, 126 females; age range, 35-65 years) with epigastric discomfort ingested capsules containing PE (PE 300mg/day) or placebo for two weeks. Using a self-rating questionnaire, they subsequently reported experiencing epigastric symptoms, including epigastric pain, heartburn, and epigastric fullness. After the ingestion period, the epigastric bloating score in the PE group (n=105) was significantly lower than that in the placebo group (n=100). These results suggest a possible beneficial effect of PE in the management of stress ulcer and epigastric bloating.

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Hydration analysis of sugars and amino acids was conducted with a focus on the viscosity of liquid food models. The interaction between pectin molecules in aqueous sugar solutions was also analyzed as a model of food macromolecule interactions. The viscosity-related parameters used for analysis of solute-solvent interactions were B_η, dB_η/dT, B_η/V₂, B_T1, and B_T2, as well as the parameters h and α. Specific viscosity-related parameters, η_sp and —dη_sp/dA_W, were used for the analysis of interactions between food macromolecules in aqueous sugar solutions. Using these parameters, it is anticipated that the mechanisms of liquid food hydration at the molecular level will be clarified in the near future.

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Low water activity and the glass state in dried foods restrict the growth of microorganisms and increase food stability. Vitrification of foods is related to the texture. Thus, hydration and vitrification are essential factors determining the physical properties and quality of foods. Inelastic neutron scattering (INS) is a promising research method for the analysis of water mobility and glass transition of food materials. Neutrons easily penetrate materials, and can be used to non-destructively investigate the molecular dynamics of food materials. INS generates information about the vibrational density of states, relaxation and diffusion processes, and mean-square displacement. Molecular dynamics (MD) simulation provides information regarding molecular structure and dynamics on an atomic scale, and is thus complementary to INS. It was found that the hydration level dependence of the onset of protein glass transition is correlated with the percolation transition of hydration water. In addition, the hydration water dynamics changed significantly at the transition temperature. The percolation of hydration water induces protein glass transition.

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