The Standard Tables of Food Composition in Japan (FCTJ) is the only official database on food ingredients and is used for various purposes in Japan. However, the method used in the FCTJ, the FCTJ manual, is sometimes unsuitable for accurately measuring some components. In this report, we focused on dietary fiber analysis mainly by reviewing resistant starch and low molecular weight water-soluble dietary fiber (LMWSDF) data. The data from three methods other than the FCTJ manual were compared as follows: AOAC 2011.25, the improved 2011.25 reported by McCleary, and a modified method of the FCTJ manual in which the LMWSDF by HPLC was added. Although the results showed that all three methods are suitable for the FCTJ, AOAC 2011.25 as a CAC Type 1 method is considered to be best suited to the FCTJ.

The protein composition of dairy products is altered with processing. In this study, we investigated the protein composition of yogurt and cheese as dairy products. First, we conducted quantitative analysis. Secondly, we extracted proteins from two kinds of yogurt and five kinds of cheese using different methods. Finally, we analyzed proteins using SDS-PAGE, immunoblot with αs1-casein (-CN) or β-lactoglobulin (-LG) specific monoclonal antibodies, and densitometric analysis. The protein composition of yogurt resembled that of cow’s milk (CM). In semi-hard and hard type cheeses, soluble proteins were not extracted. In cheese subjected to a maturation process, intact αs1-CN was lower compared to CM. Moreover, the protein composition of the fresh type cheese resembled that of CM. However, the ratio of αs1-CN to total protein was increased, as the processing of all cheeses involves a whey discharging process. In other words, β-LG was decreased in all cheeses. This study revealed that the alteration in protein composition of dairy products with processing differs depending on the processing method. These results are useful for understanding not only the amount of protein, but also its composition as basic data for dietary education.

A method for investigating the mechanical properties of bread crumb has been established in previous studies. However, there are few reports describing the effects of using whole wheat flour and the addition of enzymes (α-amylase and hemicellulase) on the mechanical properties of bread crumb during storage. Therefore, in this study, we investigated the effects of storage on the properties of the following bread crumbs: 1) made from white wheat flour as a control (C), 2) white flour combined with whole wheat flour (W) at a final ratio of 3:2 white to whole wheat flour (C＋W), and 3) C＋W with enzymes (E) added at optimal concentrations (C＋W＋E) using pullman scale bread making. Rupture force, rupture deformation and rupture energy were decreased using W, as the higher amount of insoluble dietary fiber in whole wheat flour disturbs the fine gluten network formation in dough, resulting in a weakened bread crumb structure. In comparison, C＋W＋E had a lower rupture force, a higher rupture deformation and lower viscoelastic values compared with both C and C＋W, since α-amylase and hemicellulase digest damaged starch, insoluble dietary fibers and gelatinized starch, which decrease bread making quality, during bread making, resulting in improved bread crumb texture. This study elucidated the effects of using W and the addition of E on the mechanical properties of bread crumb during storage. The addition of E made it possible to obtain high quality pullman bread using W.

We analyzed the contents of anserine, carnosine, and balenine in domestic broiler chicken, and investigated the effects of retort processing and the storage period on the total imidazole dipeptide content of chicken breast tenders. Amino acid analysis indicated the breast tenders to contain 752mg of anserine, 290mg of carnosine, and 6mg of balenine per 100g of meat. After heat processing for 30 min at 100-130°C, the total imidazole dipeptide content in breast tender meat contained in retort pouches with 0.5% (w/v) NaCl solution was approximately the same, regardless of heating temperature. The total imidazole dipeptide content after retort processing at 121°Cfor 30 min did not change after storage at normal temperature for 1 year. Our study demonstrated that this method was useful for retaining the total imidazole dipeptide content of chicken meat.

This study used senescence-accelerated prone mice (SAMP8) to examine the effects of a carbohydrate-restricted diet on aging and skin senescence, to determine how long-term carbohydrate restriction affects the aging process. Three-week-old male SAMP8 mice were divided into three groups after one week of preliminary feeding: one was given a controlled diet, another was given a high-fat diet, and the third was given a carbohydrate-restricted diet. Mice were fed ad libitum until they reached 50 weeks of age. Before the end of the test period, a grading test was used to evaluate visible aging in the mice. After the test period, serum and skin samples in mice were obtained and submitted for analysis. Results of the grading test demonstrated a significant progression of visible aging in the carbohydrate-restricted group, as well as a decreased survival rate. Histological examination of the skin revealed that the epidermis and dermis in the carbohydrate-restricted group had become thinner. Analysis of the mechanisms involved demonstrated an increase in serum interleukin-6, aggravated skin senescence, inhibition of skin autophagy, and activation of skin mTOR. Therefore, this study proved that a carbohydrate-restricted diet promoted skin senescence in senescence-accelerated mice.