We evaluated the effects of dried blueberry leaves (BL) and its hot-water extract (BLEx) on blood pressure of spontaneously hypertensive rats (SHR). A continuous 3-week administration of BL (3%) and BLEx (1.5%) reduced systolic blood pressure compared to the control group from the 2-week feeding point. Additionally, we fractionated BLEx and investigated the compound responsible for the enhanced blood pressure-lowering effect. BLEx were fractionated into 5-fractions using Sephadex LH-20 and Diaion HP20SS chromatography, and assayed for angiotensin-I-converting enzyme (ACE) inhibitory activity in vitro. The fraction composed of proanthocyanidins showed the most potent inhibitory activity (IC₅₀, 0.004mg/mL) and reduced systolic blood pressure of SHR. These results suggest that BL and BLEx have anti-hypertensive effects and one of the active components has been identified as a proanthocyanidin.

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High static pressure is thought to be the promising technique to control fermentation. The effect of high pressure treatment on the composition of microbial flora during kimchi fermentation was examined using denaturing gradient gel electrophoresis of PCR-amplified DNA followed by nucleotide sequencing of the amplicons. Eleven lactic acid bacteria (LAB) strains, including Lactobacillus, Leuconostoc and Weissella species, were isolated from kimchi. During the 60-day fermentation period, a two-stage decrease of pH to 3.9 was observed. The cell concentration of LAB reached the maximum on the 15th day, and was maintained at 3.2×10⁸ cfu/ml thereafter. Among LAB, Lactobacillus sakei was consistently observed, and Lactobacillus plantarum was observed after the 21st day. The cell concentration of yeasts reached the maximum of 1.4×10⁸ cfu/ml on the 15th day and decreased to an undetectable level after the 27th day. Kazachstania servazzii was overwhelmingly dominant. When 200 MPa high pressure treatment was applied for 60 min to the kimch on the 21st day, further decrease in pH was not observed. Cell concentrations of LAB and yeasts were suddenly reduced to 8.3×10⁵ cfu/ml and an undetectable level, and recovered gradually and rapidly, respectively. Apparent difference in the microbial flora between the pressure-free and -treated samples were not observed. Addition of L. sakei and K. servazzii at the start of fermentation did not produce an apparent effect.

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To facilitate authentic food labeling, primer sets were constructed to detect contamination with non-glutinous rice in glutinous rice processed foodstuffs. Primers for two DNA markers were designed, because each glutinous rice cultivar has either 23-bp duplication or a 7764-bp insert in the Wx gene. Single PCR products were generated using primer set F12-R14-R15, with a 163-bp fragment obtained from non-glutinous rice, and 138-bp and 186-bp fragments from glutinous rice, due to the presence of the 23-bp duplication. A 190-bp PCR product was generated with primer set F22-R05 from non-glutinous rice, whereas this fragment was not obtained from glutinous rice, which harbors the 7764-bp insert. The PCR detection rates of non-glutinous rice with these DNA markers were evaluated using mixed DNA from rice cakes made in our laboratory. The PCR detection methods exhibited a 100% detection rate at the following sensitivities. F12-R14-R15 detected non-glutinous rice content at levels exceeding 2.5%, in samples containing glutinous rice with the 23-bp duplication. F22-R05 detected non-glutinous rice content at levels above 1.0%, in samples containing glutinous rice with the 7764-bp insert. Commercial products were analyzed, and as a result, these DNA markers were amplified from their DNA. Here, we have demonstrated that these primer sets might be useful for detection of non-glutinous rice in glutinous rice processed foods, made from glutinous rice having either the 23-bp duplication or the 7764-bp insert.

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Nine kinds of glutinous rice flour were prepared by wet disk milling under various clearances (20, 40, 60μm) and rotational speeds (400, 600, 800rpm). The glutinous rice flour samples showed a mean volume diameter of 4.8-12.1, span ([d90-d10]/d50) of 1.5-3.5, and various particle forms, while macronutrients and damaged starch were almost identical. The most suitable clearance and rotational speed were empirically chosen for controlling the viscoelasticity of the dispersion paste. Under these empirical conditions, starch particle size distribution was narrow, particles were dispersed, and dynamic viscoelasticity of the dispersion paste decreased with decreasing starch concentration. The relationship between the quantity of glutinous rice flour used and the viscoelasticity of the dispersion paste indicated that glutinous rice flour prepared empirically was the most suitable method for controlling viscoelasticity.

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Fruit harvested in Fukushima Prefecture in 2012 was processed, and the concentration of radioactive cesium both before and after processing was compared. A processing factor was obtained by calculating the cesium concentration ratio of the processed products vs. raw materials. The range for each processing factor is as follows : pickled plum in salt, 0.77 to 0.98 ; pickled plum in salt water, 0.52 to 0.55 ; dried pickled plum, 0.72 to 1.11 ; plum liqueur, 0.21 to 0.32 ; plum syrup processed with sugar, 0.48 ; plum jam, 0.61 to 0.88 ; plum juice, 1.00 ; boiled fig with sugar, 1.35 ; pickled fig in syrup, 0.51 ; dried grape, 3.52 ; grape juice, 0.97 ; steamed chestnut, 1.01 ; boiled chestnut, 0.90 ; boiled chestnut (with inner skin) in syrup, 0.56 ; marron glacé, 0.20 ; citron marmalade, 0.18 ; and citron liqueur, 0.19. The radioactive cesium concentration of processed products was altered by dilution or concentration of raw materials. Radioactive cesium was transferred to the liquid from the raw material in cases of processing in a liquid, such as syrup, thereby reducing radioactive cesium in the processed products.

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New uses for rice flour are being investigated to increase the consumption of rice in Japan. In this study, we investigated the properties and taste of custard cream with rice flour prepared under various heating conditions and compared the results with those from custard cream with wheat flour. The hardness of custard cream with wheat flour (3∼9% flour content) was higher than with fine powdery rice flour. On the other hand, custard cream with rice flour prepared in the microwave oven showed similar properties and preference in sensory evaluation to wheat flour prepared under the same heating conditions.

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