For the purpose of investigating the influence of whipping speed on the characteristics of whipped cream, 45%-fat fresh cream was whipped at low speed (120 or 140 rpm) or high speed (180 or 220 rpm). The storage modulus of low-speed whipped cream did not change during storage, but a decrease in storage modulus was observed for high-speed whipped cream. The air bubble size distribution of low-speed whipped cream was stable over time, but that of high-speed whipped cream was found to increase. The reason for this phenomenon was thought to be the viscosity of the whipped cream serum. Air was introduced fully before the start of fat globule aggregation in low-speed whipped cream, but in high-speed whipped cream, fat globules began to aggregate while the overrun was increasing. The fat globule agglomerate in low-speed whipped cream was in the form of large continuous structures, but the agglomerate in high-speed whipped cream seemed to be broken into small pieces. The timing of fat globule aggregation may be the reason for the difference in physical properties between low-speed whipped cream and high-speed whipped cream.

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The breaking properties of Japanese common squid were studied by tensile and shearing tests with the aim of developing foods which can be easily bitten and are therefore suitable for elderly people. Sample strips were prepared along or across the body axis of the mantle. The mechanical properties were strongly anisotropic, deriving from the tissue structure of the squid mantle. When the sample was shorn across the axis, the breaking load from the fourth outer layer was greater than that from the inner layer. When the sample was stretched along the body axis, a lower breaking load and lower Young's modulus were observed at lower temperature and faster tensile speed. In contrast, when it was stretched across the body axis, a higher breaking load and higher Young's modulus were observed at lower temperature and faster speed. Under all of the test conditions, the breaking load and the Young's modulus for extension parallel to the body axis were greater than those for extension across the axis.

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The water absorption characteristics of adzuki beans and soybeans were examined at several temperatures ranging from 10°C to 60°C. Based on this investigation, the water absorption process was divided into two periods, the initial water absorption period and the falling rate period. The moisture content dividing the periods was around 60% (d.b.), which may be regarded as a boundary moisture content for adzuki beans. In contrast, the water absorption process of soybeans exhibited only a falling rate period. The changes in sampling data for moisture content in the initial absorption period of the adzuki beans were smoothed by a non-liner least squares method and fitted to a data curve calculated from a specific equation obtained from an approximate solution of the diffusion equation. For the falling rate periods of adzuki beans and soybeans, the sampling data plots were fitted to the data curve calculated from an approximate solution of the diffusion equation, which was similar to the data curve calculated from Page's equation in the experimental temperature range. Volume changes of the beans during soaking were determined using the experimental particle density. From an empirical equation with three parameters, it was deduced that the moisture content and the temperature were related to the specific volume.

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In order to investigate effective ways of using culled hens, we examined the possibility of utilizing chicken sarcoplasmic proteins (SP) for the rheological improvement of meat products prepared with water-washed pork loin meat. Chicken SP was extracted from breast or thigh muscle and fractionated by the salting-out method with ammonium sulfate. When model sausage mixed with each SP fraction was prepared with heating at 70°C for 30 min, the breaking stress of sausage gel containing SP fractions was found to increase ; in particular, the f3 fraction obtained as the supernatant in 75% saturated ammonium sulfate solution had a marked effect, regardless of the source of spent hen and the site of the muscle. SDS-PAGE and gel densitometry showed that every f3 fraction contained glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a protein ingredient. These results suggest that spent hen is a good source of material for use as a gelling agent in meat products.

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A flavorful vinegar was produced from boiled soybean extract by ethanol fermentation using koji and yeast followed by acetic acid fermentation using the supernatant of ethanol-fermented mash with addition of Acetobacter aceti IFO 3283. The results of sensory tests on the vinegar produced showed that rice koji for miso paste production and sake yeast Saccharomyces cerevisiae kyokai No. 77 were the most suitable ingredients for the production of vinegar from boiled soybean extract. Foaming in the fermented mash during acetic acid fermentation was found to decrease when the supernatant of ethanol-fermented mash was used. It seemed that this was caused by the degradation of saponin in the boiled soybean extract by enzymes of koji and yeast. The vinegar produced from boiled soybean extract showed radical-scavenging activity and inhibition of angiotensin I converting enzyme in vitro.

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A double-blind clinical study was carried out on subjects with Japanese cedar pollinosis for the evaluation of the effects and safety of ‘Benifuuki’ green tea, which contains epigallocatechin-3-O-(3-O-methyl)-gallate (O-methylated catechin), and a combination of ‘Benifuuki’ green tea and ginger extract, with ‘Yabukita’ green tea as a placebo. First, the effect of the combination of ‘Benifuuki’ green tea and various vegetable extracts on cytokine production inhibition was investigated using mast cells ; the simultaneous use of ‘Benifuuki’ green tea and ginger extract was found to suppress cytokine (TNF-α or MIPI-α) production to a remarkable extent. Subjects were given 1.5 g of ‘Benifuuki’ green tea, ‘Benifuuki’ green tea containing 30 mg of ginger extract, or ‘Yabukita’ green tea with water twice every day for 13 weeks. As cedar pollen scattering increased, the severity of pollinosis symptoms among the groups was observed to increase in the following order : placebo group>’Benifuuki’ group>’Benifuuki’ and ginger group. Eleven weeks after the beginning of treatment, during the most severe cedar pollen scattering period, symptoms of runny nose and itchy eyes were significantly relieved among the ‘Benifuuki’ group compared with the placebo group (p<0.05). In the ‘Benifuuki’ and ginger group, runny nose, itchy eyes and nose symptom scores were significantly reduced at the eleventh week, and nasal congestion, sore throat and nose symptom medication scores were significantly reduced at the thirteenth week compared with the placebo group. Among all test groups, hematological examination, general biochemical examination, determination of total IgG, CMV antibody titer, and serum iron content, and interviews throughout the intake period found no changes related to clinical problems. These results suggest that intake of ‘Benifuuki’ green tea over one month is useful in reducing some of the symptoms of Japanese cedar pollinosis, and did not affect normal immune response in subjects with Japanese cedar-pollinosis. It was also found that the addition of ginger extract enhanced the effect of ‘Benifuuki’ green tea.

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The antioxidative activity of rooibos tea was examined using a DPPH radical-scavenging method, and its activity when preserved in lard and in iron-enriched model cookies was investigated. The rooibos tea extract showed high DPPH radical-scavenging activity in a dose-dependent manner. When the lard preservation method was used, strong antioxidative activity was also seen. In iron-enriched cookies that did not contain the tea extract, various ferrous compounds (not including ferric pyrophosphate) were found to accelerate lipid peroxidation. With the addition of the rooibos tea extract to the iron-enriched cookies, however, lipid peroxidation, apart from heme iron preparation (HIP), was effectively prevented. These results suggest that rooibos tea extract could be utilized in high-fat foods for the prevention of lipid peroxidation.

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Microchannel (MC) emulsification is a novel technique for preparing monodispersed emulsions. Recently, we fabricated a new type of MC plate using polymer materials instead of the silicon materials used for conventional MC emulsification, and reported that monodispersed water-in-oil (W/O) emulsions were successfully prepared using an acrylic polymer MC (PMC) plate with hydrophobic properties. In this study, we modified the PMC surface with poly-2-methacryloxyethyl phosphorylcholine butyl methacrylate (Lipidure-PMB) and poly-ethylvinylalcohol (Exceval) coatings by SiO₂ spattering and SiO₂ vacuum deposition before producing oil-in-water (O/W) emulsions. Experimental results showed that the average droplet diameter and coefficient of variation were 35.7 μm and 27.0% when the emulsion was prepared using a Lipidure-PMB coated PMC plate, with a polydispersed droplet diameter distribution ; 24.3 μm and 3.8% when prepared using an Exceval-coated PMC plate, with a monodispersed droplet diameter distribution ; and 23.7 μm and 4.2% when prepared using a SiO₂ vacuum deposition PMC plate, also with a monodispersed droplet diameter distribution. When SiO₂ spattering was used, however, the hydrophilic SiO₂ film came off the plate surface during the emulsification process, and the channel was wetted by the dispersed phase, with the result that preparation of a monodispersed O/W emulsion was impossible. Furthermore, we investigated the resistance to sonic treatment of modified PMC plates, and it was found that the PMC plate modified by SiO₂ vacuum deposition demonstrated the strongest resistance to sonic treatment.

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Nitrate levels were determined by ion chromatography for 1094 samples of market vegetables. The nitrate levels (mean±standard deviation) of the vegetables are as follows : cabbage (n=189), 679±453 ppm ; Chinese cabbage (n=186), 1320±669 ppm ; head lettuce (n=174), 1060±480 ppm ; komatsuna (n=197), 4060±1720 ppm ; spinach (n=208), 3070±1360 ppm ; qing gin cai (n=20), 2750±932 ppm ; nozawana (n=20), 2840±580 ppm ; turnip (n=20), root 1630±772 ppm, leaves 3540±1700 ppm ; garland chrysanthemum (n=20), 2940±1110 ppm ; leek (n=20), 1780±567 ppm ; takana (n=20), 3680±1220 ppm ; and ta cai (n=20), 3340±1310 ppm.

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Isothiocyanates can react with amino acids to form 2-thiohydantoins. Among isothiocyanates, allyl isothiocyanate (AITC), the pungent component of wasabi and mustard, is often used as a wasabi-flavoring additive. In foods containing AITC (wasabi-fumi-pickles and wasabi-fumi-noritsukudani), 3-allyl-2-thio-5-hydantoinpropionic acid (ATH-Glu), formed by reaction of AITC and glutamic acid, was identified using high-performance liquid chromatography/mass spectrometry (LC-MS). 3-Allyl-5-isobutyl-2-thiohydantoin (ATH-Leu), 3-allyl-5-benzyl-2-thiohydantoin (ATH-Phe), and 3-allyl-5-isopropyl-2-thiohydantoin (ATH-Val), the reaction products of AITC with leucine, phenylalanine, and valine, were also identified in wasabi-fumi-noritsukudani. This is the first report demonstrating the formation of 2-thiohydantoins in commercially processed foods.

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