Aroma-active components of yeast extract pastes with a basic and characteristic meaty flavour

Comparison of nutritional profile between plant-based meat analogues and real meat: A review focusing on ingredients, nutrient contents, bioavailability, and health impacts

In order to fully understand the nutritional heterogeneity of plant-based meat analogues and real meat, this review summarized their similarities and differences in terms of ingredients, nutrient contents, bioavailability and health impacts. Plant-based meat analogues have some similarities to real meat. However, plant-based meat analogues are lower in protein, cholesterol and VB12 but higher in dietary fiber, carbohydrates, sugar, salt and various food additives than real meat. Moreover, some nutrients in plant-based meat analogues, such as protein and iron, are less bioavailable. There is insufficient evidence that plant-based meat analogues are healthier, which may be related to the specific attributes of these products such as formulation and degree of processing. As things stand, it is necessary to provide comprehensive nutrition information on plant-based meat products so that consumers can make informed choices based on their nutritional needs.

Creating alternative seafood flavour from non-animal ingredients: A review of key flavour molecules relevant to seafood

This review summarises current knowledge of the molecular basis for flavour profiles of popular seafood types (crustacean (crab, lobster, prawn, etc.), mollusc (oyster, squid, etc.), oily fish (salmon, sardine, etc.) and white fish (barramundi, turbot, etc.)), and provides a foundation for formulating improved plant-based seafood alternative (PBSA) flavours. Key odour-active volatile molecules were identified from a systematic review of published olfactometry studies and taste-active compounds and macronutrient profiles of different seafood species and commercial PBSAs from nutrition databases were compared. Ingredients commonly used in commercial BPSAs and new potential sources of flavouring agents are evaluated. While significant challenges in replicating seafood flavour and texture remain, this review provides some insights into how plant-based ingredients could be applied to improve the acceptability of PBSAs.

Flavor of extruded meat analogs: A review on composition, influencing factors, and analytical techniques

Meat analogs are anticipated to alleviate environmental and animal welfare concerns as the demand for meat rises. High moisture extrusion is commonly employed to produce meat analogs, and its flavor could influence consumers' choice. To improve the development and market demand of extruded meat analogs, flavor precursors and natural spices have been used in high moisture extrusion process to directly improve the flavor profile of extruded meat analogs. Although there have been many studies on the flavor of high moisture extruded meat analogs, flavor composition and influencing factors have not been summarized. Thus, this review systematically provides the main pleasant and unpleasant flavor-active substances with 79 compounds, as well as descriptive the influence of flavor-active compounds, chemical reactions (such as lipid oxidation and the Maillard reaction), and fiber structure formation (based on extrusion process, extrusion parameters, and raw materials) on flavor of extruded meat analogs. Flavor evaluation of extruded meat analogs will toward multiple assessment methods to fully and directly characterize the flavor of extruded meat analogs, especially machine learning techniques may help to predict and regulate the flavor characteristics of extruded meat analogs.

Study of the flavor dissipation mechanism of soy-sauce-marinated beef using flavor matrices

Soy sauce-based marinade beef (SSMB) is a traditional Chinese cuisine with a unique flavor. However, pre-precooling and air-cooling tunnels are necessary industrial units in the cold chain for flavor dissipation. Sensory-directed flavor analysis was performed to identify the key aroma-active compounds in SSMB that had just completed (100 ℃), pre-cooled in the brine tanks (45 ℃), and exited the air-cooleded tunnel (10 ℃). We identified 110 aroma-active substances, of which 42 were quantified based on their high flavor dilution factors. Recombination and omission tests identified 29 odorants as the main aroma-active molecules. Additionally, the flavor matrix revealed the relationship between the aroma component expression and sensory attributes. Flavor substances derived from spices, such as eugenol, anethole, and linalool, are enriched during the pre-cooling stage. The different meat attributes of the three samples were primarily related to aldehydes generated from lipid oxidation.

Sensory Evaluation of Plant-Based Meat: Bridging the Gap with Animal Meat, Challenges and Future Prospects

Globally, the demand for plant-based meat is increasing rapidly as these products are becoming quite popular among vegans and vegetarians. However, its development is still in the early stage and faces various technological challenges; the imitation of the sensory profile of meat is the most challenging part as these products are meant to be an alternative to animal meat. The development of a product similar to meat requires accurate selection of ingredients and processing techniques. An understanding of the relevant sensory profile can help in constructing products and technologies that are consumer-centric and sustainable. In this review, we focus on the comparative differences in the sensory profiles of animal meat and plant-based meat alternatives, particularly regarding the color, texture, and flavor, along with the methods used to compare them. This paper also explains the sensory evaluation and how it affects consumer preference and acceptability. Additionally, a direction for further research on developing better plant-based meat products is suggested.

Descriptive Sensory Attributes and Volatile Flavor Compounds of Plant-Based Meat Alternatives and Ground Beef

The objective of this study was to characterize descriptive sensory attributes and volatile compounds among ground beef (GB) and plant-based meat alternatives (PBMA). The Beyond Burger, Impossible Burger, a third brand of PBMA, regular GB, and lean GB were collected from local and national chain grocery stores. Patties were formed and cooked on an enamel-lined cast iron skillet to an internal temperature of 71 °C. A trained descriptive sensory panel evaluated patties for 17 flavor attributes and 4 texture attributes. Volatile compounds were extracted using solid phase microextraction and analyzed via gas chromatography-mass spectrometry. Distinct differences in sensory and volatile profiles were elucidated (p < 0.05). PBMA possessed decreased beef flavor intensity and increased umami, nutty, smokey-charcoal, and musty/earthy flavor compared to GB. Sensory differences corresponded with pyrazine, furan, ketone, alcohol, and aldehyde concentration differences between products. These data support the conclusion that ground beef and PBMA possess different flavor and texture characteristics. Furthermore, the flavor of PBMA varied among available retail brands.

Characterization of the off-flavor from Pichia pastoris GS115 during the overexpression of an α-l-rhamnosidase

The off-flavor of Pichia pastoris strains is a negative characteristic of proteins overexpressed with this yeast. In the present study, P. pastoris GS115 overexpressing an α-l-rhamnosidase was taken as the example to characterize the off-flavor via sensory evaluation, gas chromatography-mass spectrometer, gas chromatography-olfaction, and omission test. The result showed that the off-flavor was due to the strong sweaty note, and moderate metallic and plastic notes. Four volatile compounds, that is, tetramethylpyrazine, 2,4-di-tert-butylphenol, isovaleric acid, and 2-methylbutyric acid, were identified to be major contributors to the sweaty note. Dodecanol and 2-acetylbutyrolactone were identified to be contributors to the metallic and plastic notes, respectively. It is the first study on the off-flavor of P. pastoris strains, helping understand metabolites with off-flavor of this yeast. Interestingly, it is the first study illustrating 2-acetylbutyrolactone and dodecanol with plastic and metallic notes, providing new information about the aromatic contributors of biological products.

IMPORTANCE

The methylotrophic yeast Pichia pastoris is an important host for the industrial expression of functional proteins. In our previous studies, P. pastoris strains have been sniffed with a strong off-flavor during the overexpression of various functional proteins, limiting the application of these proteins. Although many yeast strains have been reported with off-flavor, no attention has been paid to characterize the off-flavor in P. pastoris so far. Considering that P. pastoris has advantages over other established expression systems of functional proteins, it is of interest to identify the compounds with off-flavor synthesized in the overexpression of functional proteins with P. pastoris strains. In this study, the off-flavor synthesized from P. pastoris GS115 was characterized during the overexpression of an α-l-rhamnosidase, which helps understand the aromatic metabolites with off-flavor of P. pastoris strains. In addition, 2-acetylbutyrolactone and dodecanol were newly revealed with plastic and metallic notes, enriching the aromatic contributors of biological products. Thus, this study is important for understanding the metabolites with off-flavor of P. pastoris strains and other organisms, providing important knowledge to improve the flavor of products yielding with P. pastoris strains and other organisms.

ONE-SENTENCE SUMMARY

Characterize the sensory and chemical profile of the off-flavor produced by one strain of P. pastoris in vitro.

Cultured Meat on the Social Network Twitter: Clean, Future and Sustainable Meats

The rapid development of technologies for cultured meat production has led to new challenges for producers regarding appropriate communication with future customers in order to deliver products to a viable market. Communication analysis of social media enables the identification of the key characteristics of the monitored topic, as well as the main areas of communication by individual users based on active digital footprints. This study aimed to identify the key characteristics of cultured meat based on communication analysis of the social network Twitter. Communication analysis was performed based on 36,356 Tweets posted by 4128 individual users. This analysis identified the following main communicated characteristics: clean meat, future meat, and sustainable meat. Latent Dittrich allocation identified five communication topics: (1) clean and sustainable products, (2) comparisons with plant-based protein and the impact on agribusiness, (3) positive environmental aspects, (4) cultured meat as an alternative protein, and (5) the regulation of cultured meat.

Flavor challenges in extruded plant-based meat alternatives: A review

Demand for plant-based meat alternatives has increased in recent years due to concerns about health, ethics, the environment, and animal welfare. Nevertheless, the market share of plant-based meat alternatives must increase significantly if they are to support sustainable food production and consumption. Flavor is an important limiting factor of the acceptability and marketability of plant-based meat alternatives. Undesirable chemosensory perceptions, such as a beany flavor, bitter taste, and astringency, are often associated with plant proteins and products that use them. This study reviewed 276 articles to answer the following five research questions: (1) What are the volatile and nonvolatile compounds responsible for off-flavors? (2) What are the mechanisms by which these flavor compounds are generated? (3) What is the influence of thermal extrusion cooking (the primary structuring technique to transform plant proteins into fibrous products that resemble meat in texture) on the flavor characteristics of plant proteins? (4) What techniques are used in measuring the flavor properties of plant-based proteins and products? (5) What strategies can be used to reduce off-flavors and improve the sensory appeal of plant-based meat alternatives? This article comprehensively discusses, for the first time, the flavor issues of plant-based meat alternatives and the technologies available to improve flavor and, ultimately, acceptability.

Production and characterization of yeast extracts produced by Saccharomyces cerevisiae, Saccharomyces boulardii and Kluyveromyces marxianus

In recent years, prejudice in society against monosodium glutamate (MSG) has directed food manufacturers to alternative sources. Yeast extracts are considered as "natural" due to the production process and stand out due to their nutritional properties as well as giving a flavor similar to MSG. In this study, chemical, functional and flavor properties of yeast extract powders produced from Saccharomyces cerevisiae TGM10, Saccharomyces boulardii S11 and Kluyveromyces marxianus TGM66 were evaluated. Results revealed that the most protein-rich sample was S. cerevisiae TGM10 extract (69.17%), followed by S. boulardii S11 (66.16%) and K. marxianus TGM66 (62.42%) extracts, respectively and S. cerevisiae TGM10 extract was also the richest yeast extract for essential amino acids. Additionally, flavor-enhancing amino acids such as glutamic acid, aspartic acid, alanine and glycine were dominant in S. cerevisiae TGM10 extract (47.41 g/100 g protein). Sensorial evaluation of yeast extracts demonstrated that salty taste, umami taste and meaty flavor scores of yeast extracts were lower than MSG whereas for fruity flavor, yeast extracts had the highest scores. These findings revealed the potential of three yeast strains to produce yeast extracts in order to increase the nutritional value and flavor of foods.

Characterization of Subcutaneous Fat of Toscano Dry-Cured Ham and Identification of Processing Stage By Multivariate Analysis Approach Based on Volatile Profile

During ham processing the action of endogenous proteolytic and lipolytic enzymes leads to the development of volatile compounds (VOCs) responsible of typical aromas. Protected Designation of Origin (PDO) of Toscano ham requires at least 12 months of ripening but extended seasoning might improve flavor and economic value. This study aimed at assessing the evolution of color, fatty acids, and VOCs profile in subcutaneous fat, and, among VOCs, at identifying possible markers characterizing different seasoning length. For this purpose, a reduced pool of VOCs was selected by 3 multivariate statistical techniques (stepwise discriminant analysis, canonical discriminant analysis and discriminant analysis) to classify hams according to ripening (<12 months) or seasoning (≥12 months) periods and also to seasoning length (S12, S14, S16, or S18 months). The main VOCs chemical families steadily increased along ripening. Aldehydes and hydrocarbons reached their peaks at S16, acids and ketones remained constant from R6 to S16, whereas esters started decreasing after 12 months of seasoning. Stepwise analysis selected 5 compounds able to discriminate between ripening and seasoning periods, with 1,1-diethoxyhexane and dodecanoic acid being the most powerful descriptors for ripening and seasoning period, respectively. Instead, 12 compounds were needed to correctly classify hams within seasoning. Among them, undecanoic acid methyl ester, formic acid ethyl ester, 2,4,4-trimethylhexane, and 6-methoxy-2-hexanone had a central role in differentiating the seasoning length.

Investigating characteristics and possible origins of off-odor substances in various yeast extract products

Yeast extract (YE) is rich in amino acids, nucleotides, peptides, and other flavor substances, and is a natural nutrient, umami, and flavor enhancer. However, certain YE samples impart a yeasty flavor that affects the quality parameters of YE. We compared solid-phase microextraction (SPME), solvent-assisted evaporation (SAFE), dynamic headspace sample preparation (DHS), stir bar sorptive extraction (SBSE), and other pretreatment methods for the extraction of volatiles substances in YE. SPME was selected as a suitable extraction method, and aroma extract dilution analysis (AEDA) was combined with gas chromatography-olfactometry-mass spectrometry (GC-O-MS) for identification of key odor-active compounds in 23 YE samples. The yeast off-odor substances were screened from these compounds. Principal component analysis (PCA) was used to investigate the relationship between strains and the processing of YE products and their yeasty flavor. PRACTICAL APPLICATIONS: YE is prepared primarily from baker's yeast or waste beer yeast by autolysis or enzymatic hydrolysis, and is rich in nucleotides, peptides, amino acids, and other flavor compounds. It is used globally as a common umami and flavor enhancer. However, consumers have observed that YE imparts a certain yeasty flavor that influences the overall flavor negatively. Hence, the yeasty flavor-imparting substances from 23 YE samples were investigated in this study, and the observations (including strains, processing techniques, etc.) were integrated to explain the relationship between the yeasty flavor of the YE products with strain (different yeast strain for production) or processing of YE products (enzymes used, enzymatic hydrolysis conditions, composition of products, concentration conditions of YE, etc.), or storage conditions (temperature, humidity, duration, package, etc.), providing a scientific basis for removal/lowering or masking of yeasty flavor and the improvement of flavor quality of YE products.

Characterization of Aroma-Active Compounds in Four Yeast Extracts Using Instrumental and Sensory Techniques

Gas chromatography-olfactometry coupled with sensory analysis and partial least-squares regression (PLSR) analysis led to the identification of the odorants responsible for the different flavors of four yeast extracts. Sensory analysis showed that LA00L had an intense sulfurous attribute, and LA00 was characterized by fatty and green notes, FA31 exhibited the floral odor, while KA02 had strong phenolic, animal, fermented, roasted, and caramellic notes. A total of 37 key aroma compounds with odor activity values greater than 1 were determined. 2,4-Di-tert-butylphenol and methional were the most potent aroma compounds. In addition, the key aroma compounds in LA00L were nonanal, dimethyl disulfide, and γ-decalactone. Octanal, dimethyl disulfide, and benzeneacetaldehyde were the key aroma compounds in LA00. In FA31, styrene, benzeneacetaldehyde, and acetophenone were the key aroma compounds, while indole, 2-methoxyphenol, benzeneacetaldehyde, and p-cresol contributed significantly to the aroma of KA02. PLSR showed that p-cresol and indole were significantly responsible for the phenolic and animal notes inducing the off-flavor (yeasty odor) of yeasty extracts. More significantly, indole was first reported to have an important effect on yeasty odor.

Characterization of Key Aroma-Active Compounds in Black Garlic by Sensory-Directed Flavor Analysis

Black garlic is a new garlic product produced through fermentation of fresh garlic and is very popular in Asia countries due to its health benefits. Its key aroma-active compounds were characterized by gas chromatography-olfactometry-mass spectrometry (GC-O-MS), gas chromatography-time-of-flight mass spectrometry (GC-TOFMS), and sensory evaluation. In total 52 aroma compounds were identified, and 15 of them with high flavor dilution (FD) factors based on aroma extract dilution analysis (AEDA) were selected and quantitated. Finally, 9 key aroma-active compounds, including acetic acid (sour), allyl methyl trisulfide (cooked garlic), Furaneol (caramel), diallyldisulfide (garlic), diallyltrisulfide (sulfur), (E,Z)-2,6-nonadien-1-ol (cucumber), 3-methylbutanoic acid (sweat), 5-heptyldihydro-2(3H)-furanone (apricot), and diallyl sulfide (garlic), were determined through aroma recombination and omission experiment. In addition to the sulfur-containing compounds, heterocyclic compounds were the major aroma contributors in black garlic. Sensory evaluation revealed that the flavor profile of black garlic mainly consisted of sulfur, sour, sweet, fresh, sauce, gasoline, and roasted odors.

Optimization of Headspace Solid-Phase Microextraction (HS-SPME) Parameters for the Analysis of Pyrazines in Yeast Extract via Gas Chromatography Mass Spectrometry (GC-MS)

Yeast extract was analyzed through headspace solid-phase microextraction (HS-SPME) in combination with (GC-MS) for its pyrazine compounds. Four different types of SPME fibers with various polarities were selected for preoptimization. The three coated fiber 50/30 µm DVB/CAR/PDMS showed the maximum volatile extraction efficiency and was selected for further analysis. Twenty-eight volatile compounds were tentatively identified through GC-MS including eight pyrazines and were categorically characterized as major volatile compounds responsible for the flavor enhancing notes in YE. Response surface methodology encoded with face centered central composite design was employed to optimize the experimental design. Average peak area of selected pyrazines; methylpyrazine, 2,3-dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethyl-5-methylpyrazine, trimethylpyrazine, 3-ethyl-2,5-dimethylpyrazine, tetramethylpyrazine, 3,5-diethyl-2-methylpyrazine, and 2,3,5-trimethyl-6-ethylpyrazine were optimized through RSM-CCD to get the best conditions for HS-SPME. The HS-SPME variables X₁ (equilibrium time), X₂ (extraction time), and X₃ (extraction temperature) were programed into the run sheets to opt an optimistic statistical approach. Among these, the variable X₂ and X₃ showed the most significant results with the response variable R and could be concluded as the most tantalize variables while practicing pyrazines extraction through HS-SPME method. Resultantly, the optimization methodology was successfully applied for the extraction of pyrazines from yeast extract. PRACTICAL APPLICATION: The selection of optimal conditions to conduct a HS-SPME experiment can dramatically affect the sensitivity and accuracy of aroma extraction process. Optimizing the SPME conditions is the best way to identify the role of all the possible factors that can fluctuate the volatile profile of any sample. This type of statistical approach to optimize the HS-SPME conditions for pyrazines in yeast extract was practiced for the very first time and could be considered as a prerequisite strategy to proliferate future projects related to some novel studies in terms of pyrazines flavor perception.

Mass spectrometry-based metabolomics of volatiles as a new tool for understanding aroma and flavour chemistry in processed food products

BACKGROUND

When foods are processed or cooked, many chemical reactions occur involving a wide range of metabolites including sugars, amino acids and lipids. These chemical processes often lead to the formation of volatile aroma compounds that can make food tastier or may introduce off-flavours. Metabolomics tools are only now being used to study the formation of these flavour compounds in order to understand better the beneficial and less beneficial aspects of food processing.

AIM OF REVIEW

To provide a critical overview of the diverse MS-based studies carried out in recent years in food metabolomics and to review some biochemical properties and flavour characteristics of the different groups of aroma-related metabolites. A description of volatiles from processed foods, and their relevant chemical and sensorial characteristics is provided. In addition, this review also summarizes the formation of the flavour compounds from their precursors, and the interconnections between Maillard reactions and the amino acid, lipid, and carbohydrate degradation pathways.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review provides new insights into processed ingredients and describes how metabolomics will help to enable us to produce, preserve, design and distribute higher-quality foods for health promotion and better flavour.

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.

GC-O-MS technique and its applications in food flavor analysis

Gas chromatography-olfactometry-mass spectrometry (GC-O-MS) is a combination of gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). GC-O-MS technique is a powerful tool to study food flavors and it has been widely applied for aroma and flavor analysis of various food items. In combination with different technologies, GC-O-MS can be applied to solve many flavor problems in the food industry such as quick mapping of aroma-active compounds, identification of key aroma-active compounds, cluster analysis based on the aroma-active compounds, relationship between odorants and sensory properties, and clarification of formation mechanism of important odorants. The newly proposed "molecular sensory science" concept (or sensory-directed flavor analysis) provides a much deeper research for the GC-O-MS application. Here, we have reviewed the operation, advantages and applications of GC-O-MS technique. Qualitative/quantitative analysis methods and sampling methods of aroma-active compounds have been described to introduce the different application areas of GC-O-MS. Case studies based on existing papers and our research have been discussed.

Flavour-active compounds in thermally treated yeast extracts

BACKGROUND

Aroma-active compounds and non-volatile substances determine the characteristic aroma and taste of yeast extract (YE). Changes in the characteristic aroma and taste of YE due to thermal reaction are rarely studied, and the relationship between aroma-active compounds and non-volatile compounds is not yet clear.

RESULTS

Non-volatile compounds identified by HPLC and LC/MS/MS were reduced by a rise in temperature, except for some amino acids. Peptides underwent degradation. In addition, a further rise in temperature above 120 °C resulted in a bitter and sour taste. Furans, pyrazines, thiophenes, thiazoles and some branched chain sulfur compounds were derived from GC/O/MS (SPME and SAFE). Sensory results revealed that the concentration of volatile compounds increased with an increase in temperature. The overall aroma profiles of YE at 25, 100 and 110 °C were buttery, green, nutty and meaty, while YE at 140 °C had a strong sour and sulfur odour.

CONCLUSION

The non-volatile compounds of YE were reduced and different volatile compounds were produced under different thermal treatments. There was a negative correlation between these two types of compounds. The different taste sensors and all precursors were correlated with each other. There are significant relationships between different odorants and aroma-active compounds of YE after thermal treatment. © 2018 Society of Chemical Industry.

Discovery of kokumi peptide from yeast extract by LC-Q-TOF-MS/MS and sensomics approach

BACKGROUND

Yeast extract can impart thickness, complexity and long-lasting taste impression, coined kokumi taste, to blank chicken broth. In this research, the kokumi-active peptide in yeast extract was discovered by ultrafiltration, liquid chromatographic and quadrupole-time-of-flight-tandem mass spectrometric technologies. Furthermore, the sensory characters of these peptides were evaluated by a sensomics approach.

RESULTS

A total of 10 kokumi peptides were identified from yeast extract. They were γ-Glu-Cys-Gly, γ-Glu-Leu, γ-Glu-Val, γ-Glu-Tyr, Leu-Lys, Leu-Gln, Leu-Ala, Leu-Glu, Leu-Thr and Ala-Leu. Apart from the well-known kokumi-active glutathione and γ-glutamyl dipeptides, five leucyl dipeptides were first proposed having kokumi activity. Among them, Ala-Leu was found to have the highest kokumi threshold concentration (1.5 mmol L(-1) ) in the blank chicken broth, while Leu-Glu was the lowest (0.3 mmol L(-1) ). A subsequent dose-response experiment indicated that the bitter-tasting leucyl dipeptides could impart kokumi taste to chicken broth at low concentrations (less than bitter threshold concentrations). Interestingly, the kokumi sensation began to decrease when such peptides exceeded the threshold concentration by approximately 16-fold in the blank chicken broth.

CONCLUSION

Key kokumi-active fractions were purified from yeast extract. Among them, ten important kokumi peptides from yeast extract were identified.