Effects of nutrient supplementation on fermentation kinetics, H2S evolution, and aroma profile in Verdicchio DOC wine production

Different yeast nutrient additions were studied for the 2008 and 2009 vintages of Verdicchio grape juice fermentation. Addition of yeast derivatives at the beginning of fermentation and/or different amounts of diammonium phosphate at various times within the first half of fermentation were examined, with initial yeast assimilable nitrogen concentrations set at 200 and 250 mg l^?1. Supplementation with glutathione in combination with this nitrogen addition was also evaluated. Fermentation rates were monitored throughout these fermentations carried out under different nutrient conditions. H₂S production during fermentation and synthesis of volatile compounds in the finished wines were quantified; the wines also underwent sensory evaluation. The fermentation kinetics were almost exclusively influenced by the inorganic nitrogen supplementation with diammonium phosphate. H₂S evolution was more affected by assimilable nitrogen than glutathione. Diammonium phosphate significantly reduced H₂S production, with a further reduction in the presence of yeast derivative. This nitrogen supplementation yielded higher concentrations of acetate esters, and in particular of isoamyl acetate (fruity aromas), which positively influences the analytical and aroma profile of wines and results in a general reduction in 2-phenylethanol production (floral aromas). Overall results (two harvesting times and vintages) indicate that the management with diammonium phosphate and yeast derivative supplementation improves the kinetics of fermentation and provides a good tool to reduce H₂S formation and increase the analytical and sensory quality of Verdicchio wine.     

Hydrogen sulphide production during cider fermentation is moderated by pre‐fermentation methionine addition

Yeast assimilable nitrogen (YAN) concentration and composition impact hydrogen sulphide (H₂S) production and fermentation kinetics during wine fermentation, but this phenomenon has not been extensively studied in cider fermentation. Our hypothesis was that H₂S production during cider fermentation could be decreased through pre‐fermentation modification of concentrations of individual amino acids. Apple juice (53 mg L⁻¹ YAN) was supplemented with asparagine, arginine, methionine or ammonium and fermented with EC1118 and UCD522 yeast strains. No difference in H₂S production among fermentations was observed with addition of asparagine, arginine or ammonium. Methionine addition of 5 mg L⁻¹ decreased H₂S production by yeast strain EC1118 at 53 mg L⁻¹ YAN. With 153 mg L⁻¹ initial YAN, only methionine addition of 50 mg L⁻¹ decreased H₂S production, and no tested methionine rates decreased H₂S production with 253 mg L⁻¹ initial YAN. Supplementation to 153 mg L⁻¹ YAN resulted in increased H₂S production at all methionine concentrations tested. Sensory differences in aroma were detected in samples supplemented with ammonium and methionine, and these differences were correlated with observed differences in H₂S production. Our results indicate that supplementing cider fermentations with methionine leads to lower H₂S formation, especially in apple juice containing low YAN. © 2017 The Authors Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling     

INTERACTIVE EFFECTS OF SELECTED NUTRIENTS AND FERMENTATION TEMPERATURE ON H2S PRODUCTION BY WINE STRAINS OF SACCHAROMYCES

ABSTRACT

Metabolic interactions between yeast assimilable nitrogen (YAN), biotin, pantothenic acid, and fermentation temperature that affect H₂S production by wine yeast during alcoholic fermentation were examined. Strains of Saccharomyces cerevisiae (UCD 522 and EC1118) were inoculated into a synthetic grape juice medium with H₂S evolution monitored under fermentative conditions. While a number of interactions affected the evolution of H₂S, YAN as a factor by itself was found to be not significant (P > 0.05) for both yeasts examined. Maximal cumulative H₂S production for strain UCD 522 occurred in media fermented at 30C with 60 mg/L YAN, 10 µg/L biotin, and 50 µg/L pantothenic acid while minimum production was observed with 250 mg/L YAN and 250 µg/L pantothenate. Similarly, strain EC1118 produced the most H₂S at 30C, but with 250 mg/L YAN, 0.5 µg/L biotin, and 50 µg/L pantothenic acid and the least in media that contained 250 mg/L YAN and 250 µg/L pantothenic acid.

PRACTICAL APPLICATIONS

“Reduced” off‐odors of wines, primarily associated with sulfur‐containing molecules such as H₂S, continue to be a difficulty facing winemakers worldwide. One strategy for wineries to limit these problems is to add yeast nutrients prior to fermentation, most commonly, nitrogen‐containing compounds such as diammonium phosphate. However, nitrogen deficiency is not always the sole cause for these problems. Rather, the current research suggests the need to consider factors other than nitrogen including availability of biotin and pantothenic acid as well as fermentation temperature in order to minimize these off‐odors.     

Addition of amino acids to grape juice of the Merlot variety: Effect on amino acid uptake and aroma generation during alcoholic fermentation

The effects of adding selected amino acids (phenylalanine, alanine, aspartic acid and threonine) to grape juice on the generation of aroma compounds and on amino acid uptake were studied. The fermentation kinetics varied according to the quantities of amino acids added. The fermentations finished more quickly in supplemented juices and their alcoholic content was significantly higher than in the control (p < 0.05). Amino acids were consumed mainly in the first quarter of fermentation. Higher alcohol formation took place at the same time as ethanol formation: with more amino acids present in the medium, more phenyl ethanol (p = 0.01) and benzyl alcohol were formed while isoamyl alcohol production decreased. The contents of isoamyl and phenylethyl acetates, ethyl hexanoate and ethyl octanoate, as well as most fatty acids increased during the fermentation, reaching a maximum for 10% of ethanol; with higher alcoholic contents, their concentrations decreased.     

Influence of addition of ammonium and different amino acid concentrations on nitrogen metabolism in spontaneous must fermentation

The effect of the addition of different amino acid concentrations in must on yeast nitrogen metabolism during alcoholic fermentation was studied. To do this, fermentations of Mazuelo must, poor in nitrogen compounds, were carried out. Ammonium and different concentrations of amino acids (0, 45, 120, 250 and 450 mg/l) were added to the must. Addition of 45, 120 and 250 mg/l of proteic amino acids to the must increased the rate of fermentation. Proline was mainly consumed in fermentations with smaller amounts of amino nitrogen and, at the same time, this amino acid showed the highest residual concentration in the final wines. The consumption of other proteic amino acids was directly proportional to their concentration in the musts, with the exception of leucine and isoleucine that were synthesized. However, a difference in the percentages of the amino acids consumed by the yeasts was observed. The percentages of aspartic acid, alanine and arginine consumed were higher in the fermentations supplemented with amino acids than in the fermentation where only ammonium was added. The percentages of tyrosine and phenylalanine consumed gradually increased with increase of their initial concentration.     

Influence of yeast strain on binding of sulphur dioxide in wines,and on its formation during fermentation

The amounts of sulphur dioxide bound by acetaldehyde, pyruvic acid and α-ketoglutaric acid during fermentation of three grape juices by eight wine yeasts (Saccharomyces sp.) are reported. These constituents accounted for 49–83 % (mean 69) of the measured bound SO₂, depending on the yeast strain and juice. the maximum range of concentrations of the binding components for individual wines were 10–48 ppm for acetaldehyde, 9–77 ppm for pyruvic acid and 5–63 ppm for α-ketoglutaric acid, depending on yeast strain and grape juice. the validity of the calculations was verified by an experiment with SO₂ and the three binding compounds in a multicomponent model system. The acetaldehyde content was related to the total SO₂ present, which itself was determined by the strain of yeast. SOz bound in the wines after a further SO₂ addition was correlated significantly with pyruvic and α-ketoglutaric acids, but not with acetaldehyde. Certain yeasts produced SO₂ during fermentation in grape juice and in synthetic media with defined sulphur sources. More SO₂ was produced at pH 3.6 than 3.0 in the absence of added sulphate in grape juice. Sulphate was the best sulphur source for SO₂ production in synthetic media, although some yeasts were able to produce smaller amounts of SO₂ from l-cysteine and reduced glutathione.     

Fermentation of sulphite-free white musts with added lysozyme and oenological tannins: Nitrogen consumption and biogenic amines composition of final wines

The influence on amino acid consumption and biogenic amines composition of white wines obtained by replacing SO₂ during fermentation with lysozyme and tannins was studied. At the same time, the fermentative performance of two low SO₂ producing selected yeasts strains was evaluated. For this purpose, a series of laboratory-scale fermentations of fresh white must and a HPLC-DAD method for the analysis of amino acids, biogenic amines and ammonium ion were undertaken. The presence of SO₂ or lysozyme affected the consumption of nitrogen as a function of the yeast strain, while oenological tannin had no substantial influence. Strain 1042 increased the consumption of total YAN in the presence of SO₂, as a consequence of the enhanced utilization of ammonium ion and a number of amino acids. By contrast, strain 333 tended not to change the total YAN uptake, whatever the juice treatment, and reduced the consumption of aspartic and glutamic acids, GABA and other compounds in the case of samples added with SO₂. When compared with lysozyme addition, for both strains, SO₂ increased the consumption of alanine and glutamine, the latter being a major contributor to the assimilable nitrogen of the must. No influence of must treatments was found on the content of biogenic amines in the final wines.     

Simultaneous utilization of ammonia,free amino acids and peptides during fermentative growth of Saccharomyces cerevisiae

The efficiency of nitrogen use by yeast is one of the key determinants of the successful completion of alcoholic fermentations. In this work the growth of Saccharomyces cerevisiae S288c in a synthetic medium containing ammonia and free amino acids, supplemented with yeast hydrolysate, was studied. Experiments with ¹⁵NH₄Cl and ¹⁵N‐labelled yeast hydrolysate were carried out to gain insight into which of these three classes of assimilable nitrogen sources yeast cells prefer. Co‐consumption of all three sources was observed; approximately 40% of the total nitrogen in the yeast protein fraction originated from yeast hydrolysate, while free amino acids and ammonia contributed 40 and 20%, respectively. The results indicate that several amino acids are more readily obtained from peptides, most likely when the uptake of their free forms is competitively inhibited and/or repressed. During the second half of each fermentation, a decrease in the incorporation of yeast hydrolysate‐derived nitrogen was observed. These results highlight the nutritional role of peptides in various yeast fermentations. Copyright © 2016 The Institute of Brewing & Distilling     

Apple Aminoacid Profile and Yeast Strains in the Formation of Fusel Alcohols and Esters in Cider Production

The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (<75 mg/L) nitrogen content, and four enological yeast strains, were used in cider fermentation. The aspartic acid, asparagine and glutamic acid amino acids were the majority in all the apple juices, representing 57.10% to 81.95%. These three amino acids provided a high consumption (>90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3‐methyl‐1‐butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation.     

Sucrose Fermentation by Brazilian Ethanol Production Yeasts in Media Containing Structurally Complex Nitrogen Sources

Four Saccharomyces cerevisiae Brazilian industrial ethanol production strains were grown, under shaken and static conditions, in media containing 22% (w/v) sucrose supplemented with nitrogen sources varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids) and peptides (peptone). Sucrose fermentations by Brazilian industrial ethanol production yeasts strains were strongly affected by both the structural complexity of the nitrogen source and the availability of oxygen. Data suggest that yeast strains vary in their response to the nitrogen source's complex structure and to oxygen availability. In addition, the amount of trehalose produced could be correlated with the fermentation performance of the different yeasts, suggesting that efficient fuel ethanol production depends on finding conditions which are appropriate for a particular strain, considering demand and dependence on available nitrogen sources in the fermentation medium.     

Effect of the respiro-fermentative balance during yeast propagation on fermentation and wort attenuation

Breweries use different yeast strains to create beers with different flavours and aromas. Yeast propagation must produce yeast that performs consistently from the first fermentation to harvesting and re-pitching in subsequent fermentations. Breweries propagate yeast in wort leading to low efficiency fermentative growth in Crabtree-positive yeast. There is limited knowledge on the impact on beer production when fermenting with yeast propagated in sugar limited and nutrient supplemented wort. It was hypothesised that propagating yeast in this way would have a positive impact on subsequent fermentation performance. Saccharomyces cerevisiae was propagated at the laboratory scale in standard wort with a high carbon to nitrogen (C:N) ratio (850) or in modified wort supplemented with yeast extract to achieve a low C:N ratio (100) and at varying sugar concentrations. Propagation in low C:N wort with 2°P sugar yielded a 27% decrease in fermentation efficiency and a 46% increase in cell production compared to 2°P high C:N wort. This suggests nitrogen is critical to the respiro-fermentative balance during growth. Yeast propagated in standard wort resulted in slower fermentations and significant under-attenuation compared to yeast grown in the modified wort with low sugar and high nitrogen. The results of this study suggest the nitrogen and sugar content drive the respiro-fermentative balance during yeast propagation. The metabolism of yeast during propagation induces significant downstream impacts on the subsequent fermentation performance and wort attenuation. © 2020 The Institute of Brewing & Distilling     

Partial characterization of peptides from red wines. Changes during malolactic fermentation and ageing with lees

The peptide fraction of an industrially manufactured red wine has been studied during malolactic fermentation, carried out in stainless-steel tanks or in the barrel and ageing in the barrel, with or without lees, for 12 months. Peptides were fractionated using Sephadex LH-20 and Cosmosil 140 C₁₈-OPN columns, giving two fractions in relation to peptide polarity. The most important changes were detected during malolactic fermentation and during the ageing in barrel with lees. The peptides present in the wine could be glycopeptides from grape or yeast. Most amino acids in the most polar peptides were aspartic acid and/or asparagine, glutamic acid and/or glutamine, serine, glycine, α-alanine and tyrosine and, in the less polar fraction, were glycine, α-alanine and leucine. The amino acid distribution is most different in the most polar fraction, among the studied wines, owing to autolysis and hydrolysis of the polypeptides and proteins.     

Effect of pure and mixed cultures of the main wine yeast species on grape must fermentations

Mixed inoculation of non-Saccharomyces yeasts and S. cerevisiae is of interest for the wine industry for technological and sensory reasons. We have analysed how mixed inocula of the main non-Saccharomyces yeasts and S. cerevisiae affect fermentation performance, nitrogen consumption and volatile compound production in a natural Macabeo grape must. Sterile must was fermented in triplicates and under the following six conditions: three pure cultures of S. cerevisiae, Hanseniaspora uvarum and Candida zemplinina and the mixtures of H. uvarum:S. cerevisiae (90:10), C. zemplinina:S. cerevisiae (90:10) and H. uvarum:C. zemplinina:S. cerevisiae (45:45:10). The presence of non-Saccharomyces yeasts slowed down the fermentations and produced higher levels of glycerol and acetic acid. Only the pure H. uvarum fermentations were unable to finish. Mixed fermentations consumed more of the available amino acids and were more complex and thus better able to synthesise volatile compounds. However, the amount of acetic acid was well above the admissible levels and compromises the immediate application of mixed cultures.     

Structural Complexity of the Nitrogen Source and Influence on Yeast Growth and Fermentation

The structural complexity of the nitrogen source strongly affects both biomass and ethanol production by industrial strains of Saccharomyces cerevisiae, during fermentation in media containing glucose or maltose, and supplemented with a nitrogen source varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids) and peptides (peptone). Diauxie was observed at low glucose and maltose concentrations independent of nitrogen supplementation. At high sugar concentrations diauxie was not easily observed, and growth and ethanol production depended on the nature of the nitrogen source. This was different for baking and brewing ale and lager yeast strains. Sugar concentration had a strong effect on the shift from oxido‐fermentative to oxidative metabolism. At low sugar concentrations, biomass production was similar under both peptone and casamino acid supplementation. Under casamino acid supplementation, the time for metabolic shift increased with the glucose concentration, together with a decrease in the biomass production. This drastic effect on glucose fermentation resulted in the extinction of the second growth phase, probably due to the loss of cell viability. Ammonium salts always induced poor yeast performance. In general, supplementation with a nitrogen source in the peptide form (peptone) was more positive for yeast metabolism, inducing higher biomass and ethanol production, and preserving yeast viability, in both glucose and maltose media, for baking and brewing ale and lager yeast strains. Determination of amino acid utilization showed that most free and peptide amino acids present, in peptone and casamino acids, were utilized by the yeast, suggesting that the results described in this work were not due to a nutritional status induced by nitrogen limitation.     

Fermentation of grape must by sequential association of yeasts: Accumulation of pyruvic and α-ketoglutaric acid

Fermentations of grape (cv. Malvar) musts from two consecutive vintages were carried out using the autochthonous microflora, a sequential association of yeasts and conventional fermentations with addition of sulfur dioxide to the must. The pyruvic and α-ketoglutaric acid content over the course of fermentation was measured and showed that for both vintages tested the maximum accumulation of the ketoacid pyruvic acid took place several days earlier in fermentations using a sequential association of yeasts than in conventional fermentations. The accumulation of pyruvic acid was higher in the must made from grapes with a higher degree of ripening and the lowest level of added SO₂. In the fermentations using either a sequential association of yeasts or the autochthonous microflora with no added SO₂, accumulation of α-ketoglutaric acid was higher in the must with the higher nitrogen content when the species making the greatest percentage contributions at the start of fermentation presented high levels of proteolytic activity.     

THE SENSITIVITY OF DIFFERENT BREWING YEAST STRAINS TO CARBON DIOXIDE INHIBITION: FERMENTATION AND PRODUCTION OF FLAVOUR-ACTIVE VOLATILE COMPOUNDS

The sensitivity of brewing yeast strains, with different oxygen demands, to carbon dioxide inhibition was investigated. Laboratory fermentations were performed with, and without, protein-based “yeast foods” to lower dissolved CO₂ during fermentation. Differences were observed in yeast fermentative performance in the presence and absence of “yeast foods” for all yeast strains tested. Fermentation performance was improved with the addition of “yeast foods”. There was improved carbohydrate utilisation and amino acid uptake, while acetaldehyde levels at the end of fermentation were decreased. There was an increase in fusel oil production and acetate ester levels at the end of fermentation. Sulphur dioxide levels at the end of fermentation were unaffected by “yeast food” addition. Different yeast strains displayed differing sensitivity to CO₂ inhibition for all parameters tested. Sensitivity to CO₂ was not found to be related to oxygen demand of the yeast strains.     

Multifactorial analysis of acetaldehyde kinetics during alcoholic fermentation by Saccharomyces cerevisiae

Acetaldehyde is the terminal electron acceptor in the alcoholic fermentation by Saccharomyces cerevisiae. Quantitatively the most important carbonyl by-product, it has relevance for ethanol production yields as well as product stabilization and toxicology. The aim of this study was to investigate the effect of various enological parameters on acetaldehyde kinetics during alcoholic fermentations. Two commercial yeast strains were tested in two grape musts and the pH, temperature, SO₂ and nutrient addition were varied. All incubations had uniform kinetics where acetaldehyde reached an initial peak value followed by partial reutilization. Peak acetaldehyde concentrations and residual concentrations after 15 days of fermentations ranged from 62 to 119 mg l^− 1 and 22 to 49 mg l^− 1, respectively. A positive linear relationship was found between peak and final acetaldehyde levels in Gewürztraminer, but not Sauvignon Blanc fermentations, where sluggish fermentations were observed. Several factors had a significant effect on peak and/or final acetaldehyde levels. SO₂ addition, grape cultivar and fermentation nutrition were important regulators of peak acetaldehyde production, while final acetaldehyde concentrations were correlated with SO₂ addition, grape cultivar and temperature. The results allowed to estimate the acetaldehyde increase caused by SO₂ addition to 366 ??g of acetaldehyde per mg of SO₂ added to the must. The course of the final fermentation phase was shown to determine acetaldehyde residues. Comparison of acetaldehyde and hexose kinetics revealed a possible relationship between the time of occurrence of peak acetaldehyde concentrations and the divergence of glucose and fructose degradation rates.     

Volatile compound production in Agave duranguensis juice fermentations using four native yeasts and NH4Cl supplementation

Nitrogen has a significant effect on the fermentation rate and the chemical composition of alcoholic beverages. Nitrogen deficiency during fermentation of Agave juice for mescal production can lead to slow fermentations and end-products with low aromatic compound variety. In this study, the effects of NH₄Cl supplementation on volatile compound formation in Agave duranguensis juice fermented at 28?°C with the native yeast strains Saccharomyces cerevisiae ITD00185, Hanseniaspora uvarum ITD00108, Torulaspora delbrueckii ITD00110 and Kluyveromyces marxianus ITD00211 were analysed. Nitrogen content in the Agave juice unsupplemented with NH₄Cl was low. In the control treatments, the four yeasts consumed nitrogen at approximately the same rate, almost completely finishing by 24?h. Nitrogen supplementation increased biomass production with S. cerevisie, H. uvarum and T. delbrueckii but not with K. marxianus. K. marxianus consumed the total assimilable nitrogen more slowly than the other strains in the supplemented fermentations. In addition, the volatile compound profile differed between the studied yeasts. Volatile compound production by S. cerevisiae, H. uvarum and K. marxianus was higher in the supplemented fermentations, compared to the unsupplemented ones. In T. delbrueckii, the initial volatile compound concentrations remained unchanged, or decreased for some compounds, with nitrogen supplementation. The initial acetic acid and vanillin concentrations decreased with all strains tested and nitrogen supplementation. Furthermore, the concentration of higher alcohols increased with S. cerevisiae and H. uvarum in the NH₄Cl-supplemented fermentations, but they decreased with T. delbrueckii and K. marxianus. In conclusion, the addition of an inorganic nitrogen source promotes microorganism metabolism, increases biomass formation and benefits the fermentation process.     

Part II: the influence of the serial repitching of Saccharomyces pastorianus on the uptake dynamics of amino acids during the fermentation of barley and gluten‐free buckwheat and quinoa wort

The present paper is part of a comprehensive study regarding the influence of the serial repitching of Saccharomyces pastorianus TUM 34/70 on the composition of the barley, buckwheat and quinoa fermentation medium. In particular, it focuses on the uptake dynamics of amino acids during 11 successive fermentations. Samples were taken every 20 h after pitching, analysed for the particular amino acid content and statistically evaluated. The term ‘completion time’ (t₉₅), here defined as the percentage attenuation time necessary for ~95% of the total assimilation, has been introduced. In addition, ‘the serial repitching factor’ is used for the first time to support the visual evaluation of the influence of serial repitching. Amino acids that were essentially affected by serial repitching were glutamine, arginine, alanine and tryptophan in barley, aspartate, glutamate and tryptophan in buckwheat, and all in the quinoa wort fermentation. As opposed to buckwheat and quinoa, in barley the amino acids behaved more or less independently from each other, which for buckwheat and quinoa indicates a more general systemic change in the yeast. From the amino acids point of view, buckwheat can be fully regarded as a suitable gluten‐free substitute for barley beer since the amino acid assimilation was very consistent and hardly influenced by the serial repitching, especially regarding the final amino acid assimilation. In the case of quinoa, the assimilation of all amino acids became significantly affected after the sixth fermentation and quinoa is probably unsuitable for the production of beer‐like beverages. Results suggest no substitutional potential of quinoa for barley beer, but if a nutrient‐rich beverage of choice from quinoa malt is intended to be prepared, it seems that the serial repitching is limited to six fermentations at most. Copyright © 2015 The Institute of Brewing & Distilling     

Biodiversity and safety aspects of yeast strains characterized from vineyards and spontaneous fermentations in the Apulia Region,Italy

This work is the first large-scale study on vineyard-associated yeast strains from Apulia (Southern Italy). Yeasts were identified by Internal Transcribed Spacer (ITS) ribotyping and bioinformatic analysis. The polymorphism of interdelta elements was used to differentiate Saccharomyces cerevisiae strains. Twenty different species belonging to 9 genera were identified. Predominant on the grape surface were Metschnikowia pulcherrima, Hanseniaspora uvarum and Aureobasidium pullulans, whereas M. pulcherrima and H. uvarum were dominant in the early fermentation stage. A total of 692 S. cerevisiae isolates were identified and a number of S. cerevisiae strains, ranging from 26 to 55, was detected in each of the eight fermentations. The strains were tested for biogenic amines (BAs) production, either in synthetic media or grape must. Two Pichia manshurica, an Issatchenkia terricola and a M. pulcherrima strains were able to produce histamine and cadaverine, during must fermentation. The production of BAs in wine must was different than that observed in the synthetic medium. This feature indicate the importance of an “in grape must” assessment of BAs producing yeast. Overall, our results suggest the importance of microbiological control during wine-making to reduce the potential health risk for consumer represented by these spoilage yeasts.