Taste Dilution Analysis Research Articles

Coumarins rather than alkylamides evoke the numbing orosensation of pomelo peel

Liangpingyou, a well-known Chinese pomelo (Citrus grandis L.) variety, elicits a unique and uncharacterized numbing aftertaste. To understand the molecular bases and characteristics of the pomelo-induced numbing sensation, we first determined that hydroxyl sanshools, the major Sichuan pepper chemosensates, were not responsible via silylation-GC–MS analysis. Pomelo peel juice was then subjected to solid-phase extraction to form 4 fractions, and key sensory-active substances were screened via taste dilution analysis. Three simple coumarins, meranzin hydrate, isomeranzin, and marmin, were identified to induce numbing, which has not been previously reported. Sensory studies via extensively modified half-tongue tests and verification steps revealed recognition thresholds within 0.49–1.78, 0.32–1.56, and 0.43–1.46 μmol/L for numbness, pungency, and astringency, respectively. The temporal dominance trends showed the following taste notes: Meranzin hydrate–numbing dominated, isomeranzin–numbing and pungent, and marmin–astringent and numbing. Molecular docking analysis suggested that coumarins target the receptors TRPV1, TPRA1, and KCNK3

Low molecular weight peptides in tauco, a fermented soy product, associated to umami taste through peptidomics‐sensomics approach

SummaryUmami peptides from ultrafiltration fractions of tauco have never been revealed yet. This study's objective was to determine umami peptides by peptidomics‐sensomics approach followed by molecular docking on the ultrafiltration fractions of tauco with MWs <3 kDa from different regions of Indonesia. Sensory evaluation by taste dilution analysis to determine umami intensity and peptide identification by HR‐LC–MS/MS were conducted. Seventeen peptides were revealed to be associated with the intense umami taste of tauco fractions, having molecular weights of 1106–1760 Da. The molecular mechanism and binding energy affinity of the peptides to umami receptor T1R1/T1R3 heterodimer through molecular docking confirmed the result. Peptides IPVNKPGRF, DVFRAIPSEV, and DVTDVTGDRGVTVT are 3 of the 17 identified peptides which have the lowest binding energy to umami receptor T1R1/T1R3 at −9.4, −9.2, and −9.1 kcal mol−1, respectively. In addition, the molecular docking results indicated that His145, Asn68, Val277, and Ser67 of taste receptor type 1 member 3, T1R3 subunit, play critical roles in the binding with identified umami peptides by forming hydrogen bonds and hydrophobic interaction.

Molecular Characterization and Quantification of Saponins from Sugar Beet (Beta vulgaris ssp. vulgaris var. altissima)

Consumer demand for sustainably and ecologically produced food has grown in recent years. However, for numerous reasons, this demand has not always been met. New solutions are still being sought, particularly in the area of emulsifiers, an integral ingredient of many food products. The biggest challenge is the limited scope of application offered by current alternatives. While some progress has been made using foam active quillaja saponins, they are neither pleasant‐tasting nor sustainably produced. Only very little is known about other alternatives, and especially the behavior of saponins, particularly on a molecular level, is not very well understood. Moreover, it is often not known which parts of a plant contain the highest levels of saponins and are therefore most suitable for extraction.To expand the current level of knowledge about emulsifying and foam active extracts, saponin extracts were made from oat bran, beetroot as well as sugar beet and characterized in close cooperation with the Department of Food Physics and Meat Science at the University of Hohenheim. Measurements conducted on these extracts showed that foam activity is a good indicator of their emulsifying ability. The most promising one ‐ sugar beet extract ‐ was examined in more detail using taste dilution analysis, which revealed saponin fractions with a slight off‐taste and high foam activity. A series of eight saponins was obtained from these fractions and further characterized, together with three commercially available ones that were identified using non‐targeted screening. The unequivocal identification and structure elucidation was performed using a combination of liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) and both one‐dimensional (1D) and two‐dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy. For most substances, this was the first time that a complete assignment of 1H and 13C NMR signals had been made. All of these saponins possess taste recognition values above 1000 μmol/L, which is higher than most values for the taste‐ active saponins reported in the literature. The foam activity of these substances was measured using a self‐developed small‐scale foam activity assay. It was measured for different concentrations of saponins in a buffer solution. The foam activity of numerous other saponins was also determined, resulting in the most comprehensive overview of the foam activities of individual saponins.In addition to these isolation and characterization activities, an LC‐MS/MS method of performing simultaneous quantitative analyses of all the obtained sugar beet saponins was developed and validated. These were quantified in several sugar beet varieties (root and leaves), different sugar beet compartments, and side streams originating during the sugar beet converting process. Great variations in mass fractions were found in these materials, ranging from 862 mg/kg to 2,452 mg/kg for the various sugar beet root varieties and from 907 mg/kg to 5,398 mg/kg for the sugar beet leave varieties. Sugar beet fiber was identified as the best saponin source, with a total saponin quantity of 12.7 g/kg, followed by dried sugar beet pulp, with a total quantity of 10.3 g/kg. As a by‐product stream, dried sugar beet pulp is highly suitable for the sustainable manufacture of saponins.The results obtained are of key significance to the utilization of sugar beet saponins as well as saponins extracted from other plant materials or by‐product streams for use as food additives.

An overview of bitter compounds in foodstuffs: Classifications, evaluation methods for sensory contribution, separation and identification techniques, and mechanism of bitter taste transduction.

The bitter taste is generally considered an undesirable sensory attribute. However, bitter-tasting compounds can significantly affect the overall flavor of many foods and beverages and endow them with various beneficial effects on human health. To better understand the relationship between chemical structure and bitterness, this paper has summarized the bitter compounds in foodstuffs and classified them based on the basic skeletons. Only those bitter compounds that are confirmed by human sensory evaluation have been included in this paper. To develop food products that satisfy consumer preferences, correctly ranking the key bitter compounds in foodstuffs according to their contributions to the overall bitterness intensity is the precondition. Generally, three methods were applied to screen out the key bitter compounds in foods and beverages and evaluate their sensory contributions, including dose-over-threshold factors, taste dilution analysis, and spectrum descriptive analysis method. This paper has discussed in detail the mechanisms and applications of these three methods. Typical procedures for separating and identifying the main bitter compounds in foodstuffs have also been summarized. Additionally, the activation of human bitter taste receptors (TAS2Rs) and the mechanisms of bitter taste transduction are outlined. Ultimately, a conclusion has been drawn to highlight the current problems and propose potential directions for further research.

Isolation and identification of bitter-tasting peptides in Shaoxing rice wine using ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with taste orientation strategy

The content of peptides in Shaoxing rice wine is high; however, their potential taste properties have not yet been studied. To isolate and identify bitter-tasting peptides in a popular Chinese rice wine, Shaoxing rice wine, a series of purification steps including ultrafiltration and gel filtration chromatography (GFC), combined with a taste orientation strategy, were used. According to the evaluation results of taste dilution analysis, a bitter peptide with the highest taste efficacy was isolated, and its purity was verified by high-performance liquid chromatography (HPLC). The amino acid sequence of peptide components was analyzed by ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS). The bitter peptide Leu-Pro-Thr-Leu (LPTL) was successfully identified from Shaoxing rice wine. Then, taste addition experiments highlighted the bitter impacts of LPTL on sensory descriptors in Shaoxing rice wine. The LPTL peptide can contribute to bitterness in Shaoxing rice wine.

Analysis of key precursor peptides and flavor components of flaxseed derived Maillard reaction products based on iBAQ mass spectrometry and molecular sensory science

Flaxseed derived Maillard reaction products (MRPs) have typical meaty flavor, but there is no report on comparison of their amino acids and peptides reactivity. The peptides and amino acids of flaxseed protein hydrolysates were separately collected by G-15 gel chromatography. Taste dilution analysis (TDA) showed that peptides-MRPs had high umami, mouthfulness, and continuity enhancement. Further, LC-MS/MS revealed that flaxseed protein hydrolysates consumed 41 peptides after Maillard reaction. Particularly, DLSFIP (Asp-Leu-Ser-Phe-Ile-Pro) and ELPGSP (Glu-Leu-Pro-Gly-Ser-Pro) accounted for 42.22% and 20.41% of total consumption, respectively. Aroma extract dilution analysis (AEDA) indicated that formation of sulfur-containing flavors was dependent on cysteine, while peptides were more reactive than amino acids for nitrogen-containing heterocycles. On the other hand, 11 flavor compounds with flavor dilution (FD) ≥ 64 were identified for flaxseed derived MRPs, such as 2-methylthiophene, 2-methyl-3-furanthiol, furfural, 2-furfurylthiol, 3-thiophenethiol, thieno[3,2-b] thiophene, 2,5-thiophenedicarboxaldehyde, 2-methylthieno[2,3-b] thiophene, 1-(2-methyl-3-furylthio)-ethanethiol, 2-methylthieno[3,2-b] thiophene, and bis(2-methyl-3-furyl)-disulfide. In addition, we further demonstrated the flavors formation mechanism of flaxseed derived MRPs.

Identification and Quantitation of Taste-Active Compounds in Dried Scallops by Combined Application of the Sensomics and a Quantitative NMR Approach.

Application of the sensomics concept on dried scallops, a Japanese specialty produced from the adductor muscle of scallops, revealed after activity-guided fractionation with subsequent (comparative) taste dilution analyses besides nucleotides, amino acids, organic acids, and inorganic ions, the presence of taste-modulating quaternary ammonium compounds and opines in highly taste-active fractions. In order to recreate the taste of dried scallops, two independent quantitation approaches were applied and compared. The first approach used multiple targeted UHPLC-MS/MS and high-performance ion chromatography methods. Besides already established quantitation methods for basic taste compounds, a new HILIC-UHPLC-MS/MSMRM method for the quantitation of chromatographically challenging opines, using synthesized stable isotope-labeled standards, was developed. Furthermore, a qHNMR approach was applied, enabling a direct identification and quantitation of organic taste compounds in a food extract without prior fractionation using a reference 1H NMR database. Both methods yielded similar quantitative results of taste-active compounds in dried scallop extracts and subsequent taste recombination experiments based on these data were able to recreate the taste of dried scallops.

Sensory-Guided Multidimensional Exploration of Antisweet Principles from Gymnema sylvestre (Retz) Schult.

We report on activity-guided investigation of the key antisweet principles of Gymnema sylvestre. Orosensory-guided fractionation by means of solid phase extraction, preparative 2D-LC, and semipreparative HPLC followed by accurate MS and 1D/2D NMR experiments revealed six known and three previously unknown gymnemic acids as the key constituents of seven highly sensory-active fractions. Localized via a modified comparative taste dilution analysis (cTDA) and taste modulation probability (TMP) based screening techniques, a strong intrinsic bitterness was also observed for gymnemic acids. In addition, the suppressive effects of the most abundant acids on the response of the human sweet taste receptor to sucrose were verified by means of a functional hTAS1R2/hTAS1R3 sweet taste receptor assay. This in vitro screening revealed large differences in antisweet activity among the isolated compounds, where gymnemic acids XV and XIX showed the highest sweet suppressing activity. This broad-based molecular characterization of the sweet taste inhibiting activity of Gymnema sylvestre will enable further insight into the molecular basis of sweet taste modulation at the receptor level.

Identification of bitter‐taste compounds in class‐III caramel colours

AbstractCaramel colours become one of the most widely used colorings in various foods and beverages due to their total miscibility with water and great coloring properties by containing colloidal aggregates. Bitterness in caramel colours can negatively influence their acceptability. The sequential solvent extraction (SSE) and semi‐preparative liquid chromatography (SP‐LC) combined with the taste dilution analysis were applied to identify the most intense bitter‐tasting compounds in class‐III caramel colours. Four main compounds with the highest bitterness intensity were isolated and structurally elucidated based on high resolution‐electrospray ionization‐mass spectrum (HR‐ESI‐MS), nuclear magnetic resonance (NMR) spectroscopy and gas chromatography‐mass spectrum (GC‐MS): 2,3‐dihydro‐3,5‐dihydroxy‐6‐methyl‐4(H)‐pyran‐4‐one (DDMP), 5‐(hydroxymethyl) furfural (HMF), furfural and 5‐methylfurfural (MF). The threshold concentrations of DDMP, HMF, furfural and MF were 14.3, 30.0, 4.4 and 17.5μmol L−1, respectively. Furthermore, two volatile bitter compounds were identified: [5‐(di‐methoxymethyl) furan‐2‐yl] methanol (DMFM) and 2,3,4,4‐tetramethyl‐pentane‐1,3‐diol (TMP). Based on the composition of the caramel colours and the structures of these compounds, Maillard reaction was supported to generate these bitter compounds in caramel colour‐III.

Isolation and identification of umami‐flavored peptides from Leccinum extremiorientale and their taste characteristic

Umami, as one of the five basic tastes, is important to the taste of food. In this study, gel filtration chromatography and reversed-phase high-performance liquid chromatography were used to isolate and purify Leccinum extremiorientale cooked at high temperature. Sensory evaluation and taste dilution analysis were used to identify the most umami component in L. extremiorientale. Most umami components were determined by LC-MS/MS. Three umami peptides were identified, and they were Asp-Gln-Glu-Asp-Leu-Asp-Glu-Ser-Leu-Ile-Gly-Val-Lys (DQEDLDESLIGVK), Phe-Asn-Glu-Ile-Ile-Lys-Glu-Thr-Ser-Thr (FNEIIKETST), Tyr-Asn-Glu-Tyr-Pro-Pro-Leu-Gly-Arg (YNEYPPLGR). As far as we know, this is the first time that umami peptides have been extracted from Boletus. This study can provide a basis for the development of delicious food with Boletus characteristics. Novelty impact statement Three umami peptides were isolated and purified from Leccinum extremiorientale for the first time. The structure characteristics of the umami peptides were analyzed according to the sequence. The results can provide practical application for the food industry.

Characterization of Bitter and Astringent Off-Taste Compounds in Potato Fibers.

Applying the sensomics approach, a combination of activity-guided fractionation and taste dilution analysis (TDA) followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), ultrahigh-performance liquid chromatography time-of-flight mass spectrometry (UHPLC-TOF-MS), and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy (1D/2D NMR) allowed the elucidation of key off-taste compounds in potato dietary fiber isolates. Previously already having been described as off-taste compounds in potato tubers, saponins α-chaconine and α-solanine were shown to be also major contributors to overall off-taste in potato fiber isolates. Moreover, fatty acids as well as fatty acid oxidation products, namely, E-9,10,13-trihydroxy-octadec-11-enoic acid as well as newly identified compounds hexadecyl(E/Z)-ferulate and octadecyl(E/Z)-ferulate, were shown to be key inducers to off-taste in the isolates, exhibiting taste recognition thresholds between 18 and 981 μmol/L. This paper demonstrates the isolation, structure determination, quantitation as well as sensory attributes of these key off-taste compounds.

Chromatographic Profiles of Umami Fractions from Indonesian Commercial Salty Soy Sauce

Salty soy sauce subjected in this study is a variety of commercial soy products in Indonesia. Chromatographic profiles linked to taste dilution analysis of the soy sauce were analyzed by Sephadex G-15 gel filtration chromatography followed by RP-HPLC. The results showed that there were 4 umami fractions (Fractions I − IV) obtained by Sephadex G-15 separation. Chromatographic profiles at 254 nm could show the differentiation of the four fractions and then their RP-HPLC profiles were proven to be different from each other. Fraction III which contained 65% of the soy sauce dry matters, had the highest umami intensity with umami TD factor of 256, meanwhile, this fraction was tasted salty due to the salt contained in the soy sauce. Fraction III was dominated by the later peaks in the RP-HPLC chromatogram, which was more hydrophobic. The hydrophobic components were commonly tasted bitter, perhaps in the commercial salty soy sauce, the taste interaction between the umami and bitter components might have occurred.

Umami fractions obtained from water-soluble extracts of red oncom and black oncom-Indonesian fermented soybean and peanut products.

Red oncom, a fermented product from solid waste of soybean curd process, and black oncom, a similar fermented product but made from defatted peanut cake, have been known to have umami taste. Umami fractions of red oncom and black oncom that are responsible for umami taste have not been investigated yet. The objective of this research was to characterize umami fractions obtained by ultrafiltration and chromatography of both oncoms. The first step, water-soluble extracts of oncoms were ultrafiltered using a membrane with cutoff 3,000Da and followed by gel filtration chromatography (Sephadex G-25) to obtain umami fractions. Ultrafiltration fractions of red oncom (molecular weight [MW] less than 3,000Da) and black oncom (MW more than 3,000Da) had an intense umami taste. The further fractionation by gel filtration chromatography linked to taste dilution analysis yielded umami fractions. Chemical characterization revealed that free glutamic acid, free phenylalanine, and peptides containing their residual amino acids were present in the fractions. PRACTICAL APPLICATION: Umami fractions of red and black oncoms can be used as a source of umami compounds for food industries and food services. The information from this paper can be used by other researchers who will explore umami peptides.

Molecularization of Bitter Off-Taste Compounds in Pea-Protein Isolates (Pisum sativum L.).

Activity-guided fractionations, combined with taste dilution analyses (TDA), were performed to locate the key compounds contributing to the bitter off-taste of pea-protein isolates (Pisum sativum L.). Purification of the compounds perceived with the highest sensory impact, followed by 1D/2D-NMR, (LC-)MS/MS, LC-TOF-MS, and MSE experiments, led to the identification of 14 lipids and lipid oxidation products, namely, 9,10,13-trihydroxyoctadec-12-enoic acid, 9,12,13-trihydroxyoctadec-10-enoic acid, 9,10,11-trihydroxyoctadec-12-enoic, 11,12,13-trihydroxyoctadec-9-enoic acid, (10E,12E)-9-hydroxyoctadeca-10,12-dienoic acid, (9Z,11E)-13-hydroxyoctadeca-9,11-dienoic acid, (9E,11E)-13-hydroxyoctadeca-9,11-dienoic acid, 1-linoleoyl glycerol, α-linolenic acid, 2-hydroxypalmitic acid, 2-hydroxyoleic acid, linoleic acid, (9Z,11E)-13-oxooctadeca-9,11-dienoic acid, and octacosa-6,9,19,22-tetraen. Herein, we present the isolation, structure determination, and sensory activity of these molecules. Depending on their structure, the isolated compounds showed human bitter recognition thresholds between 0.06 and 0.99 mmol/L in water.

Sensory-guided identification of bitter compounds in Hangbaizhi (Angelica Dahurica).

As a traditional Chinese medicine, Angelica dahurica (Fisch. ex Hoffm.) Benth. et Hook. f. ex Franch. et Sav. cv. Hangbaizhi (Hangbaizhi) is not only used for the curative treatment of diseases such as the common cold and toothache, but also is an important spice that is used to increase the aroma and remove the unpleasant odor in many foods. Hangbaizhi has however, been reported to cause a bitter taste. In this study, the bitter compounds in Hangbaizhi after three common processes (boiling, frying and boiling after frying) were studied. Six bitter compounds (oxypeucedanin hydrate, bergapten, xanthotoxol, imperatorin, isoimpinellin and oxypeucedanin) were identified by high performance liquid chromatography (HPLC)-diode array detection (DAD)-electrospray ionization (ESI)-tandem mass spectrometry (MS) and sensory evaluation. The contribution of these bitter compounds was ranked by taste dilution analysis (TDA). Upon the assessment of methods to reduce the bitter flavor, it was found that baijiu (Chinese liquor) pretreatment was more effective than water-pretreatment.

6-(2-Formyl-5-methyl-1H-pyrrol-1-yl)hexanoic Acid as a Novel Retronasal Burnt Aroma Compound in Soy Sauce Aroma-Type Chinese Baijiu.

Two-step high-performance liquid chromatography (HPLC) separation in combination with taste dilution analysis was used to screen the retronasal burnt aroma compounds in soy sauce aroma-type Chinese Baijiu (Chinese traditional liquor). A major retronasal burnt aroma region was purified by Sephadex LH-20 column chromatography and HPLC separation from the soy sauce aroma-type Baijiu sample. A novel retronasal burnt aroma compound was identified as 6-(2-formyl-5-methyl-1H-pyrrol-1-yl)hexanoic acid (1) by means of high-resolution mass spectrometry and 1D/2D nuclear magnetic resonance. The retronasal burnt aroma threshold of compound 1 was determined to be 209.5 μg/L in 53% ethanol aqueous solution. Quantitative analysis showed that the concentration of compound 1 ranged from below the limit of quantitation (3.8 μg/L) to 224.2 μg/L in the Baijiu samples. Moreover, the sensory evaluation also revealed that compound 1 may contribute to the retronasal burnt aroma of the Baijiu at its subthreshold concentration by the additive effect with the recently reported retronasal burnt aroma compound 2-hydroxymethyl-3,6-diethyl-5-methylpyrazine.

Taste Modulating Peptides from Overfermented Cocoa Beans.

Activity-guided fractionation of an aqueous extract of overfermented cocoa beans, which were recently found to be a rich source of previously unknown taste enhancing substances, revealed the presence of a series of taste modulating short peptides. Fractionation was achieved by means of sequential solvent extraction, medium pressure liquid chromatography, as well as preparative high pressure liquid chromatography, and the taste modulating activity was determined by means of matrix assisted taste dilution analysis. By means of ultra performance liquid chromatography-time-of-flight-mass spectrometry (UPLC-ToF-MS) screening, liquid chromatography-MS/MS methods, and customized syntheses, numerous short peptides could be identified in the taste modulating fractions. Sensory experiments of the target peptides showed umami enhancing and salt taste enhancing properties as well as kokumi effects when applied in a savory taste matrix. Evaluation of the taste threshold concentrations in model broth demonstrated a high taste modulating potential of 11 out of 13 identified peptides. Lowest threshold concentrations were determined for the salt taste enhancing tripeptide pEEE (55 μmol/L) and the kokumi active tripeptide VPA (90 μmol/L). Furthermore, a large number of dipeptides, carrying either a prolyl- or pyro-glutamyl moiety were located in the aqueous extract, exhibiting taste modulating properties and revealing a pH dependency of the taste modulating effect of the savory taste matrix. Additionally, synergistic effects of a mixture of five umami enhancing pyro-glutamyl dipeptides in the model matrix were demonstrated.

Kaempferol 3- O-(2‴- O-Sinapoyl-β-sophoroside) Causes the Undesired Bitter Taste of Canola/Rapeseed Protein Isolates.

By means of activity-guided fractionation using taste dilution analysis, liquid chromatography-tandem mass spectrometry (LC-MS/MS), liquid chromatography-time-of-flight mass spectrometry, one-/two-dimensional nuclear magnetic resonance spectroscopy, LC-MS/MS quantitation, dose-over-threshold considerations, and sensory spiking experiments, kaempferol 3- O-(2‴- O-sinapoyl-β-sophoroside), exhibiting a bitter taste above the low threshold concentration of 3.4 μmol/L, was found for the first time as the key molecule contributing to the unpleasant bitter taste of rapeseed (canola) protein isolates. This finding opens new avenues for a biorefinery approach targeting an off-taste removal.

Isolation and identification of the umami peptides from shiitake mushroom by consecutive chromatography and LC-Q-TOF-MS

Umami is critical to the taste of shiitake mushroom. To isolate and identify umami peptides, fractions from hydrolyzed dried shiitake mushroom were separated by ultrafiltration, gel filtration chromatography (GFC), and reversed-phase high-performance liquid chromatography (RP-HPLC). Separations were combined with sensory evaluations (grading and taste dilution analysis) and analysis of electronic tongue, which were used to identify the most umami component in shiitake mushroom. Low-molecular-weight fractions (MW < 3 kDa) have the strongest flavor in the shiitake mushroom hydrolysate. In the 3 subfractions separated from low-molecular-weight fractions (MW < 3 kDa) by GFC, the second subfraction (F2) was selected for RP-HPLC analysis. The first peak (G1) in RP-HPLC was identified by LC-Q-TOF-MS, and 2 tripeptides and 3 dipeptides were identified. The amino acid sequence of these peptides were Gly-Cys-Gly, Glu-Pro-Glu, Cys-Met, Val-Phe, and Gly-Glu.

The behavior of umami components in thermally treated yeast extract

Umami proteolytics are natural food flavor alternatives to glutamate. In this study, key umami taste fractions were separated and purified from thermally treated yeast extract (YE) to yield fifteen umami peptides. Systematic approaches using sensory-guided fractionation on taste-active umami proteolytics separation and detection were utilized. A reaction temperature of 110 °C was optimum for umami peptide generation. Under this reaction temperature, the sensory score and E-tongue results of umami taste were the highest. The sensory evaluation-based taste dilution analysis and taste threshold determination supported the hypothesis that umami peptides have their physiological effect by binding to G-protein coupled receptors. The structural differences of umami peptides contribute to their taste profile and allow categorization into two group Types. Fifteen umami peptides were then categorized into Type I and Type II regarding the contractual-based taste mechanism: Type I peptides imparted complex tastes. The tastes of Type I peptides could split into two stages: bitterness and umami in pure water, whereas, Type II peptides presented strong umami taste at a high concentration in pure water, and the relationship between umami capacity and peptides concentration was linear. Finally, the guidance of the umami peptide usage in the flavor industry has been established according to broths dissolution test.