Publications by authors named "Miho Imamura"

Soy sauces can be classified into three categories based on the production method used: honjozo, kongojozo (mixed-brewing, amino acid-decomposed), and kongo (mixed, amino acid-decomposed) soy sauces. Although differences in flavor between traditional (honjozo) and modern (amino acid-decomposed) soy sauces are clear, knowledge of the differences in compound profiles and the relationship between these and the sensory characteristics that affect soy sauce quality is limited. Therefore, this study aimed to investigate the differences between traditional and modern soy sauce compounds using metabolomic analysis, and to investigate the compounds that may be correlated with differences in flavor.

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Article Synopsis
  • Researchers created a new method using graphite carbon black (GCB) combined with laser desorption ionization mass spectrometry (LDI-MS) to analyze taste and odor compounds in food.
  • They tested this method on various soy sauces and successfully differentiated products based on their country of origin (Japan, China, India) without complicated sample preparation.
  • The analysis provided clear chemical patterns and distinct mass spectrometry peaks that correlated with the quantity of compounds in the soy sauces, establishing GCB-LDI-MS as an efficient tool for food quality assessment.
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In order to clarify the aroma characteristics of raw soy sauce (RS), the application of gas chromatography-olfactometry analysis to the aroma concentrate from a RS revealed 76 aroma peaks, of which 25 peaks showed fruit-like aromas. Furthermore, the head space aromatic compounds of RS were analyzed with 32 peaks detected. Ethyl 2-methylpropanoate, ethyl butanoate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, and ethyl 4-methylpentanoate were detected with higher flavor dilution factor (FD factor) than other aroma compounds by aroma extract dilution analysis.

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The cooked meat-like aroma compound, 2-methyl-3-furanthiol (2M3F), was detected in fermented soy sauce (FSS) by GC-olfactometry and GC-MS. 2M3F was present in FSS at a concentration considerably greater than the perception threshold, and the 2M3F concentration increased with heating temperature. Sensory analysis indicated that with the addition of only 0.

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A metabolic profiling approach was employed to explore the compounds that affect the intensity of umami taste in soy sauce. Twenty-five kinds of soy sauces were analyzed using GC-MS and LC-MS, wherein measurement data for 427 compounds were obtained. The umami taste intensity of each soy sauce sample was also quantitated by sensory evaluation and a projection to latent structure (PLS) regression analysis was conducted using the compounds' measurements and umami taste intensity data.

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Characterizing the relationships between the components and taste differences among soy sauces can help evaluate and improve the quality of soy sauces. Although previous studies have reported that certain taste-active dipeptides, the relationships between taste differences and dipeptides of soy sauces are unknown. Therefore, our objective in this study was to investigate the correlations between the dipeptides and the taste differences among soy sauces.

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Umami is one of 5 basic tastes that make foods savory and palatable. The umami aftertaste is a long-lasting taste sensation that is important for Japanese broth (dashi) utilized for various Japanese foods. Soy sauce is usually added when making dashi-based dishes; however, different soy sauces produce distinct effects on the umami aftertaste.

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Soy sauces, produced from different ingredients and brewing processes, have variations in components and quality. Therefore, it is extremely important to comprehend the relationship between components and the sensory attributes of soy sauces. The current study sought to perform metabolite profiling in order to devise a method of assessing the attributes of soy sauces.

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The distribution of an antihypertensive dipeptide, Val-Tyr (VY), in the tissues of spontaneously hypertensive rats (SHR) was investigated in this study. A single oral administration of VY (10 mg/kg) to 18-week-old SHR resulted in a prolonged reduction of systolic blood pressure (SBP) up to 9 h (SBP0h 198.0+/-3.

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