Food is always of crucial importance for health. From ancient times, Asian and European people have shared the common concept that medicine and food are isogenic, regrettably with no scientific evidence available. It was only about 100 years ago that modern food science had humble beginnings. Initially, it progressed along a path of development through nutrition. After World War II, however, public climate focused on palatable rather than nutritional properties of foods. Academic studies in the field of cooking science as well as food chemistry were activated accordingly. Food industry also began to supply a plenty of palatable products to the market, but it often led some people to satiety and unbalanced dietary practice that may cause life style-related diseases. In response, an ad hoc research team in Japan started to work and, in 1984, proposed the name, concept, and examples of “functional food” as what is now known as a new category of foods which can modulate some target functions of the body and reduce the risk of these diseases. In general, functional foods are designed and produced by fortification with physiologically functional rather than purely nutritional components. Since Nature (1993)reported on the state of the art with the headline “Japan explores the boundary between food and medicine”, the terminology “functional food” has glocally propagated. European countries have been very keen on developing new products with enhanced function claims and disease risk reduction claims. This inevitably needs the use of biomarkers that warrant the validity of the claims. Meanwhile, the human genome program was completed, with the birth of nutrigenomics as its application in the field of nutrition and functional food science. This sophisticated methodology already has practical use to develop effective biomarker at the DNA level. It will also be used to create “tailor-made”foods which should be applied to persons by taking into consideration their individual genetic differences in health and disease. As cooking science has long recognized the importance of the fact that different people like different tastes, the science on food and health is gradually approaching to a similar target in view of esteeming individuality.

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The aim of this study is to provide an accurate method for assessing nutrient contents to aid nutritional surveillance and menu preparation. Animal products in the “Standard Tables of Food Composition in Japan, Fifth Revised Edition” were categorized by food group, method of cooking, and other factors.
The rate of component change by cooking in each group of animal products was examined, and could be classified into 17 levels. Differences in the rates of component change by cooking were apparent between the food groups and even within the same food group.
The evaluated rates of component change by cooking can be used for estimating the amount of nutritional components that remain after cooking. This computation utilizes the nutritional value of the components in uncooked food and the nutritional component value after it has been cooked to obtain the rates of component change by cooking.
It is therefore possible to compute the amount of nutritional components for cooked food with no nutritional component value. This improves the accuracy for calculating the nutritional value in nutritional assessment and menu preparation.

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We have studied the microscopic structure of biscuits and revealed an acceleration mechanism of the spreading of the biscuit by egg yolk. We prepared dough containing emulsified fat with the yolk or an emulsifier, measured some physical properties (compression test, DSC measurement and relative density), and considered the spread and the inside structure of biscuit by microscopy.
The yolk, as well as the emulsifier accelerates the homogeneous dispersion of the fat in the dough and the binding of wheat protein with water in the dough. These phenomena increased the viscosity of the dough; therefore, we consider that the yolk markedly increases the spreading of the biscuit. As a result of the study of the water-yolk-fat emulsion we conclude that the function of the yolk depends on its emulsionc omponents.

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The effects of mixtures of 0.5% calcium carbonate (CaCO₃) and 0-1.0% magnesium salts (MgCl₂ or MgSO₄) on the thermal and rheological properties of 47.6% non-glutinous rice flour dough were investigated by measuring the DSC characteristics, X-ray diffraction patterns, storage moduli and loss moduli of dough samples, and by observing SEM images. Unheated dough containing a mixture of 0.5% CaCO₃ and 1.0% of either magnesium salt showed greater linking of starch particles than that containing 0.5% CaCO₃ alone based on the SEM observation. The water absorbed by heated dough was less after adding a mixture of 0.5% CaCO₃ and 0.5% or 1.0% MgCl₂ than dough containing 0.5% CaCO₃ alone (p<0.05). Adding either MgCl₂ or MgSO₄ decreased the values of the rupture properties of unheated dough containing 0.5% CaCO₃. The rupture stress and rupture energy of heated dough containing CaCO₃ and the figures for dough containing CaCO₃ soaked in ionized water were both increased by adding either MgCl₂ or MgSO₄.

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The effects of mixtures of 0.5% calcium hydroxide (Ca(OH)₂) and 0-1.0% magnesium salts (MgCl₂ or MgSO₄)on the thermal and rheological properties of 47.6% non-glutinous rice flour dough were investigated by measuring DSCcharacteristics, X-ray diffractionpatterns, storage moduliand loss moduliof doughsamples and by observing SEM images. SEM observation showed many pores in the heated dough containing the mixture of 0.5% Ca(OH)₂and 1.0% MgCl₂ or 1.0% MgSO₄. An endothermic peak in the dough containing Ca(HO)₂ was shifted to higher temperature by adding 0.25% MgCl₂ or 0.25% MgSO₄. The X-ray diffraction pattern of heated dough containing a mixture of Ca(OH)₂ and MgCl₂ or MgSO₄ was gently cone-shaped. The values for the rupture properties of unheated dough containing Ca(OH)₂ were decreased and rupture stress of the heated dough containing Ca(OH)₂were increased by adding MgCl₂ or MgSO₄.

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An attempt was made to follow the changes in macro-and microscopic states of starch granule-in-water systems during gelatinization due to heating. A microscopic examination, DSC measurement and observation of the mechanical responses under a small stress were conducted to examine the effect of gelatinization of the starch components on the rate of increase of the internal temperature of foodstuffs during cooking. It was confirmed that the starch granules from potato and wheat showed a much higher degree of swelling in the corse of gelatinization than those from glutinous and non-glutinous rices and corns. However, the results obtained from DSC measurement indicated that the apparent heat of gelatinization was highest with potato starch (-27.3mJ) among the samples tested, while that for wheat starch was the lowest (-15.2mJ). The mechanical responses to a low stress, i. e. instantaneous elasticity and steady flow viscosity, were characterized by a type of convex curves according to the progress of gelatinization for all the samples tested. These responses started to increase at the beginning of gelatinization, attained maximal values at around 70°C corresponding to disappearance of the crystal region in the starch molecules, and finally tended to decrease with further temperature increase.
The results obtained from this study will be utilized in future work to examine the effect of gelatinization on the increase of internal temperature of foodstuffs during cooking.

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A survey was carried out of the use of persicaria in traditional fermented foods in the Xiangshan district of Zhejiang province in People's Republic of China. It was found that the starter derived from an extract of-“perscaria”-is used in producing mantou and unrefined sake. Bacillus, Lactobacillus, Streptococcus, Staphylococcus, yeast, and fungi ware present in the persicaria starter. The bacteria that ware separated from the starter showed high activity for collagen resolution. It was also found that the enzyme of bacterium which decomposes the wheat allergen protein was being produced. Crude enzymes of the bacteria in the starter had proteolytic activity toward the allergenic in both the salt-soluble and saltinsoluble fractions of the wheat proteins.

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Smaller hens's eggs and yolks are composed of smaller yolk spheres, and vice-versa for larger yolks. We examined whether the size of the yolk spheres was related to the size of eggs and yolks in eggs from different birds. The cross-sectional area of the yolk spheres in the intermediate layer of steamed yolks was measured by the image-processing technique.
The weights of the eggs and yolks from different birds were greatest in the ostrich (>duck>White-Leghorn >Nagoya>guinea fowl>quail). The weight of an ostrich egg was about 25 times greater than that of hen eggs,, and about 120 times greater than that of quail eggs. The cross-sectional area of yolk spheres was greatest in the White-Leghorn (>ostrich>duck>Nagoya>quail>guinea fowl). There was no significant correlation between the cross-sectional area of yolk spheres and the yolk weight in eggs from different birds (r=0.12).
The kinds of bird egg cannot be identified by the different cross-sectional areas of the yolk spheres.

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Seasoned tuna meat dzuke in Japanese, was prepared from bigeye tuna meat by using a contact dehydration sheet (CDS), and the effect of CDS on the permeation of seasoning into the tuna meat was examined. The tuna meat decreased in weight by 0.71% during a CDS treatment at 2°C for 1h. After soaking in soy sauce seasoning at 2°C for 2h, the CDS-treated and-untreated samples had respectively decreased in weight by 0.64% and 1.39%. Both the color difference (ΔE^*ab) and sodium chloride concentration in the inner parts of the CDS-treated samples were significantly higher than those of the untreated samples after soaking in the seasoning for 1h, suggesting that the CDS treatment was effective for permeating seasoning into the tuna meat. A sensory evaluation also revealed that the CDS-treated samples were significantly higher in saltiness, soy sauce color, and overall preference as dzuke than the untreated samples.

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Rice was washed by using a whisk at three mixing speeds: one revolution per second, two revolutions per second and four revolutions per second. The rice was also washed by hand at two revolutions per second as a control. The proportion of rice granules broken when the whisk was used was higher than that when washed by hand under all the conditions examined, the higher the mixing speed, the higher the breakage ratio. The amount of solid material separated from the rice granules into the water during washing was also higher when a whisk was used than when washed by hand, although there was no effect from the mixing speed. The textural and sensory properties of the cooked rice that had been washed by using a whisk were not significantly different from those of the cooked rice that had been washed by hand. We conclude from these results that washing rice by whisking affects the integrity of the grains and offers no advantages over hand washing.

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Akamoku, Sargassum horneri, is the brown algae widely distributed along the coast of the Sea of Japan, but it is only used as a food in limited local areas. This study examines the minerals, free amino acids and fatty acid composition of fresh akamoku fronds and packaged commercial boiled akamoku.
Although the major component minerals such as Na and K were significantly decreased by boiling, there were no considerable changes in the other minerals. The free amino acid contents, excepting glutamic acid and glutamine, were dramatically decreased by boiling. The fatty acid composition was not significantly changed by boiling in comparison with the minerals and free amino acids, although the lipid content of packaged commercial boiled products was less than that of fresh akamoku fronds.
The results show marked differences after boiling both fresh and commercial akamoku fronds, mainly in the contents of free amino acids, Na and K.

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