We investigated retronasal aroma (Fukumi-ka) and orthonasal aroma (Tachi-ka) of buckwheat, rice and barley Shochu using retronasal aroma simulator (RAS) with artificial saliva because retronasal aroma of Shochu has not been investigated. Shochu samples were treated with RAS, and their volatile compounds were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). In total, 24, 27 and 23 compounds were identified from, buckwheat, rice and barley Shochu respectively. Notably, middle-chain fatty acid ethyl esters as ethyl caprylate, ethyl caprate, ethyl laurate and ethyl myristate showed a remarkable decrease as reflected by the differences in peak area when analyzed in artificial saliva. We found that these results were caused by an α-amylase. Therefore, we examined the effects of artificial saliva and concentration of long-chain fatty acid ethyl esters in model solution containing middle-chain fatty acid ethyl esters. When concentrations of long-chain fatty acid ethyl esters in orthonasal aroma were increased, peak area of middle-chain fatty acid ethyl esters in addition to artificial saliva except for ethyl caproate in that decreased. This study clarified that the relation between retronasal aroma of Shochu and saliva components is important and orthonasal aroma of Shochu relates strongly to long-chain fatty acid ethyl ester.

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Fourteen plain Chinese chicken bouillons, 14 plain Japanese chicken bouillons and 4 dried bonito and kelp stocks, one of the basic Japanese stocks, were collected, analyzed and compared their free amino acids, nucleotides, sugar, organic acids, minerals, phosphorus, nitrogen, crude fat, contents, and also brix were measured. Results of the analysis showed significant differences in the quantities of taste components such as glutamic acid, taurine, potassium and ash between the Chinese chicken bouillons and Japanese chicken bouillons. While Chinese chicken bouillons contained more glutamic acid, Japanese chicken bouillons were more rich in potassium, comparatively higher in IMP as one of umami taste and amino acids which have sweet taste. Based on the taste components of the 32 samples, it was found that the 3 stock samples fell into 3 distinct groups according to the principal component analysis. Moreover, it was confirmed with discriminant analysis that the 3 groups were discriminated based on the result of the taste component analysis, specially, in Asp, Glu, Met, Phe, His and Ca. The 3 groups of stocks were also discriminated by their aroma sensor patterns. It was confirmed that Chinese chicken bouillon and Japanese chicken bouillon differ to some extent in respect to taste and aroma although both were made from similar materials. It is suggested that Chinese and Japanese differ in their preference in taste and aroma.

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Application of the aroma extract dilution analysis (AEDA) using the volatile fraction before and after heat processing green tea samples resulted in the detection of nine odor-active peaks for which the flavor dilution (FD) factors changed. Seven potent odorants were identified from these peaks by gas chromatography-mass spectrometry (GC-MS). Among these components, methional, linalool, phenylacetaldehyde, β-damascenone, geraniol, and 2-methoxy-4-vinylphenol showed the highest FD factors after heat processing of the green tea drinks. However, the increase in the amount of these potent odor-producing compounds made a difference in the various heat processing conditions. It was suggested that this phenomenon occured because the amount of these compounds generated in different with each compound by the heating conditions.

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We prepared anthocyanin-rich extract from purple-fleshed sweet potato (Ipomoea batatas (L.) Lam.) cultivar “Ayamurasaki” (PSP-ANT) and examined hypotensive effect of PSP-ANT in spontaneously hypertensive rats (SHR). After a single ingestion (400 mg/kg p.o.) of PSP-ANT, a significant decrease of systolic blood pressure (p<0.05) was observed at 2 hours postadministration and the decrease was prolonged until 8 hours postadministration in SHR. The antihypertensive effect was also observed in a long-term ingestion (0.1 and 0.2% diet for 8 weeks) of PSP-ANT in SHR. After stopping the feed of PSP-ANT, the systolic blood pressure was almost the same as that of SHR fed control diet.

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