Sampling plans for food testing adopted in official documents published by countries and international organizations are reviewed. The aim of this review was to summarize the information contained in various documents and to identify the risk level for producers and consumers in the international food trade. Sampling policies described in several official documents, such as the directives of the European Commission and the Code of Federal Regulations of the United States, are introduced. The relation between lot size and sample size during bulk sampling was summarized and fitted to several functions, which showed that sample size is roughly proportional to the square root of the lot size.

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For baked starch products with different gelatinization levels such as rice senbei, cookies, etc., the relationship between physical properties and water content of monolayers (Wm) and multilayers (MC) was investigated in commercial baked products at various temperatures and relative humidity (RH) levels. The range of water content for brittle and Wm values was maximum at 5°C and minimum at 40°C. The water content ranges and Wm values were increased with higher product gelatinization levels. Irrespective of the temperatures tested, the RH region of brittle corresponded well to the RH region of Wm in the desorption process. The MC ranges for both RH and water content may be intimately involved in alterations in the physical properties of commercial baked products irrespective of the temperature, as shown with hand-made baked products.

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We previously showed that the Japanese diet in 1975 was more effective than the modern Japanese diet for preventing obesity. Since one feature of the 1975 Japanese diet was lower meat intake, we hypothesized that replacing sausage, which is widely eaten in modern Japan, with boiled fish paste, which a traditional Japanese dish, will have a beneficial effect on health. SD rats were fed test diets containing powdered sausage or boiled fish paste for four weeks. The results showed that, compared with the sausage diet, the boiled fish paste diet lowered plasma and hepatic lipid concentrations, as well as lipid peroxide levels. Next, we prepared artificial boiled fish paste based on the nutritional balance of protein, fat and carbohydrate and sodium found in boiled fish paste. SD rats were either fed test diets mixed with artificial boiled fish paste or original boiled fish paste for four weeks. The results showed that the original boiled fish paste lowered plasma lipid concentration and lipid peroxide levels more than the artificial boiled fish paste. In conclusion, it was shown that changing the diet from sausage to boiled fish paste had a beneficial effect to health by reducing lipid concentration and lipid peroxide levels, and that this effect does not completely depend on the nutritional balance of boiled fish paste.

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The purpose of this study was to clarify the relation between microstructure and physical properties of a food capsule shell-model that can be used to form a wet-gel or a dry-film. Gels and films were prepared using a gelatin/maltodextrin mixed system. The microstructures of the gels and films were observed by confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Both the gels and films showed a phase-separated structure comprising a gelatin-rich continuous phase and a maltodextrin-rich dispersed phase. The size of the dispersed-phase tended to increase with increasing maltodextrose molecular weight. Furthermore, the film structure was quantified and classified sequentially by its phase-separated structure based on average longest diameter (ALD) of the dispersed phase : macro (DE4, ALD : 9.7μm), semi-macro (DE1, ALD : 4.7μm), micro (DE16, ALD : 1.7μm), and homo (DE18, no phase separation). The fractured distortion decreased as the average longest diameter of the dispersed phase in the film increased. A decrease in the area ratio of the continuous phase was concomitant with an increase in the dissolution time and the load at low distortion. These results suggested that the size of the maltodextrin-rich dispersed phase of gels and films can be controlled by choosing the appropriate molecular weight of maltodextrin. Furthermore, it became clear that the phase separated structure of films altered the physical properties of the film such as crumbliness, hardness, and insolubility.

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We previously reported an extraction methodology for preparing an antioxidant powder from spent eggplant pre-pickling solution. This antioxidant powder exhibited low water-solubility and a strong acetic acid odor. Here, treatment with β-cyclodextrin and γ-cyclodextrin was investigated to address these undesirable characteristics. The amount of nasnin and chlorogenic acid contained in the antioxidant powder was determined. The optimum condition for improving the characteristics of the powder were obtained by mixing γ-cyclodextrin and the powder in a 1 : 1 molar ratio, γ-cyclodextrin : nasnin/chlorogenic acid, and stirring for more than 10 minutes. This treatment increased the water-solubility of the antioxidant powder from 32 % to 81 % and decreased the odor of acetic acid by 81 %. We also evaluated the functional properties of the cyclodextrin inclusion complex. The ORAC value for the cyclodextrin inclusion complex was estimated to be 5159 μmol trolox equivalent/g. The complex exhibited high antioxidant activity, equivalent to 56.2 % of the activity of the delphinidin standard. The anti-allergic effect was assessed by measuring hyaluronidase inhibitory activity and was found to be almost equal to Saibokuto, an anti-allergic agent.

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Starch contributes to the texture of various foods through its gelling properties. We recently reported that limited hydrolysis of starch granules with α-amylase was a powerful tool to enhance the gelling properties of cassava starch ( J. Appl. Glycosci., 61, 15-20 (2014)). This study aimed to combine the novel enzymatic method with a conventional chemical cross-linking method, widely employed in improving the gelling properties of starch. Phosphate cross-linked cassava starch (PS) and PS subsequently treated with α-amylase from A. niger (PAS) were produced from native cassava starch (NS), and their gelatinization and gelling properties were investigated. Among the three starches tested, PAS produced the most elastic gel, indicating that this enzymatic method is effective on PS.

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The effect of high-amylose rice gel, which was prepared by high-speed shear treatment (HST) of gelatinized rice, added to wheat dough on the physical properties of the obtained bread (rice gel bread) was investigated. Regardless of the amount of additional water, the specific volume of rice gel bread was higher than that of rice porridge bread, which contained gelatinized rice without HST. The specific volume of rice gel bread was not dependent on the amount of additional water in the samples. Except for the bread samples with 65% additional water, no obvious difference in viscoelastic moduli of crumb samples was observed between rice gel bread and rice porridge bread. The change rate of rice gel bread viscoelastic properties during storage decreased with increases in the amount of additional water, whereas that of rice porridge bread increased.

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