Biogenic amine synthesis in high quality Tempranillo wines. Relationship with lactic acid bacteria and vinification conditions

A Comparative Study of Microbial Communities, Biogenic Amines, and Volatile Profiles in the Brewing Process of Rice Wines with Hongqu and Xiaoqu as Fermentation Starters

Rice wine is primarily crafted from grains through saccharification and liquification with the help of Qu. Qu plays an important role in the formation of the flavor quality of rice wine. Hongqu and Xiaoqu represent two prevalent varieties of Qu that are typically utilized in the brewing process of rice wine and play a crucial role in its production. In this study, GC, GC-MS, HPLC, and metagenomic sequencing techniques were used to contrast the microbial flora, biogenic amines, and aroma characteristics developed during the fermentation of rice wines, with Hongqu and Xiaoqu being used as initiating agents for the brewing process. The results show that the content of higher alcohols (including n-propanol, isobutanol, 3-methyl-1-butanol, and phenethyl alcohol) in rice wine brewed with Xiaoqu (XQW) was significantly higher than that in rice wine brewed with Hongqu (HQW). Contrarily, the concentration of biogenic amines in HQW surpassed that of XQW by a notable margin, but tyramine was significantly enriched in XQW and not detected in HQW. In addition, a multivariate statistical analysis revealed distinct disparities in the constitution of volatile components between HQW and XQW. Hexanoic acid, ethyl acetate, isoamyl acetate, ethyl caproate, ethyl decanoate, 2-methoxy-4-vinylphenol, etc., were identified as the characteristic aroma-active compounds in HQW and XQW. A microbiome analysis based on metagenomic sequencing showed that HQW and XQW had different dominant microorganisms in the brewing process. Burkholderia, Klebsiella, Leuconostoc, Monascus, and Aspergillus were identified as the primary microbial genera in the HQW fermentation period, while Pediococcus, Enterobacter, Rhizopus, Ascoidea, and Wickerhamomyces were the main microbial genera in the XQW brewing process. A bioinformatics analysis revealed that the concentrations of microbial genes involved in biogenic amines and esters biosynthesis were significantly higher in HQW than those in XQW, while the content of genes relevant to glycolysis, higher alcohol biosynthesis, and fatty acid metabolism was significantly higher in XQW than in HQW, which are the possible reasons for the difference in flavor quality between the two kinds of rice wine from the perspective of microbial functional genes.

Integrated meta-omics approaches reveal Saccharopolyspora as the core functional genus in huangjiu fermentations

Identification of the core functional microorganisms in food fermentations is necessary to understand the ecological and functional processes for making those foods. Wheat qu, which provides liquefaction and saccharifying power, and affects the flavor quality, is a key ingredient in ancient alcoholic huangjiu fermentation, while core microbiota of them still remains indistinct. In this study, metagenomics, metabolomics, microbial isolation and co-fermentation were used to investigate huangjiu. Although Aspergillus is usually regarded as core microorganism in wheat qu to initiate huangjiu fermentations, our metagenomic analysis showed that bacteria Saccharopolyspora are predominant in wheat qu and responsible for breakdown of starch and cellulose. Metabolic network and correlation analysis showed that Saccharopolyspora rectivirgula, Saccharopolyspora erythraea, and Saccharopolyspora hirsuta made the greatest contributions to huangjiu's metabolites, consisting of alcohols (phenylethanol, isoamylol and isobutanol), esters, amino acids (Pro, Arg, Glu and Ala) and organic acids (lactate, tartrate, acetate and citrate). S. hirsuta J2 isolated from wheat qu had the highest amylase, glucoamylase and protease activities. Co-fermentations of S. hirsuta J2 with S. cerevisiae HJ resulted in a higher fermentation rate and alcohol content, and huangjiu flavors were more similar to that of traditional huangjiu compared to co-fermentations of Aspergillus or Lactiplantibacillus with S. cerevisiae HJ. Genome of S. hirsuta J2 contained genes encoding biogenic amine degradation enzymes. By S. hirsuta J2 inoculation, biogenic amine content was reduced by 45%, 43% and 62% in huangjiu, sausage and soy sauce, respectively. These findings show the utility of Saccharopolyspora as a key functional organism in fermented food products.

Level of Biogenic Amines in Red and White Wines, Dietary Exposure, and Histamine-Mediated Symptoms upon Wine Ingestion

Biogenic amines (BAs) are involved in physiological processes. Foods where typically high levels of BAs occur are fermented food and beverage. This work set out to evaluate the occurrence of BAs in red and white wines, and to also ascertain the dietary exposure to BAs among consumers. Besides, a case report of a probable histamine intoxication upon ingestion of contaminated wine was described. The samples were analyzed through derivatization with dansyl chloride and HPLC-UV detection. Red wines showed higher levels of BAs, especially putrescine (PUT) and histamine (HIS), than white wines (median concentrations of 7.30 and 2.45 mg/L, respectively). However, results of our investigation showed that the dietary exposure to BAs through the consumption of wine (red and white) were lower than the recommended maximum levels for the acute exposure to HIS and tyramine (TYR). In contrast, the levels of BAs in wine on tap were much higher than in bottled wine and close to recommended values. The levels of HIS, TYR, and PUT in tap wine of 9.97, 8.23, and 13.01 mg/L, respectively, were associated with histamine-mediated symptoms in six young individuals after consumption of about three glasses of wine. The overall results and multivariate analysis confirm that red wine shows a higher concentration of BAs than white wine, especially putrescine and histamine. This finding is attributable to the malolactic fermentation that is common for most red wine production. It is also evident that incorrect preservation processes can lead to an increase in BA levels, probably due to the action of bacteria with high decarboxylase activity. The exposure values, although below the toxicity thresholds, could lead to histamine-mediated symptoms in susceptible individuals, also according to the case report discussed in this study.

The Management of Compounds that Influence Human Health in Modern Winemaking from an HACCP Point of View

The undesirable effects of some hazardous compounds involved in the different steps of the winemaking process may pose health risks to consumers; hence, the importance of compliance with recent international food safety standards, including the Hazard Analysis and Critical Control Point (HACCP) standards. In recent years, there has been a rise in the development of new technologies in response to the hazardous effects of chemical compounds detected during the winemaking process, whether naturally produced or added during different winemaking processes. The main purpose was to reduce the levels of some compounds, such as biogenic amines, ethyl carbamate, ochratoxin A, and sulfur dioxide. These technological advances are currently considered a necessity, because they produce wines free of health-hazardous compounds and, most importantly, help in the management and prevention of health risks. This review shows how to prevent and control the most common potential health risks of wine using a HACCP methodology.

Accumulation of Biogenic Amines in Wine: Role of Alcoholic and Malolactic Fermentation

Biogenic amines (BAs) are detrimental to health and originate in foods mainly from decarboxylation of the corresponding amino acid by the activity of exogenous enzymes released by various microorganisms. BAs can be generated at different stages of the wine production. Some of them are formed in the vineyard and are normal constituents of grapes with amounts varying with variety, soil type and composition, fertilization and climatic conditions during growth and degree of maturation. BAs can be also formed by the yeasts during the alcoholic fermentation (AF), as well as by the action of bacteria involved in the malolactic fermentation (MLF). As aminogenesis is a complex and multifactorial phenomenon, the studies carried out to identify the main vinification stage of BAs production yielded contradictory results. In particular, there is not a general consensus yet on which fermentation supports mostly the accumulation of BAs in wine. In this context, the aim of the present paper deals with the most recent results related with the influence of alcoholic and malolactic fermentation parameters on BAs-producer microorganism in wine.

Ability of Kocuria varians LTH 1540 To Degrade Putrescine: Identification and Characterization of a Novel Amine Oxidase

This work describes the identification and characterization of an amine oxidase from Kocuria varians LTH 1540 (syn. Micrococcus varians) primarily acting on putrescine. Data from MALDI-TOF MS/MS and the identification of Δ(1)-pyrroline as degradation product from putrescine indicate that the enzyme is a flavin-dependent putrescine oxidase (PuO). Properties of partially purified enzyme have been determined. The enzyme oxidizes diamines, putrescine and cadaverine, and, to a lesser extent, polyamines, such as spermidine, but not monoamines. The kinetic constants (Km and Vmax) for the two major substrates were 94 ± 10 μM and 2.3 ± 0.1 μmol/min·mg for putrescine and 75 ± 5 μM and 0.15 ± 0.02 μmol/min·mg for cadaverine. Optimal temperature and pH were 45 °C and 8.5, respectively. Enzyme was stable until 50 °C. K. varians PuO is sensitive to human flavin-dependent amine oxidase inhibitors and carboxyl-modifying compounds. The new enzyme has been isolated from a bacterial starter used in the manufacture of fermented meat. One of the problems of fermented foods or beverages is the presence of toxic biogenic amines produced by bacteria. The importance of this works lies in the description of a new enzyme able to degrade two of the most abundant biogenic amines (putrescine and cadaverine), the use of which could be envisaged to diminish biogenic amines content in foods in the future.

Implications of new research and technologies for malolactic fermentation in wine

The initial conversion of grape must to wine is an alcoholic fermentation (AF) largely carried out by one or more strains of yeast, typically Saccharomyces cerevisiae. After the AF, a secondary or malolactic fermentation (MLF) which is carried out by lactic acid bacteria (LAB) is often undertaken. The MLF involves the bioconversion of malic acid to lactic acid and carbon dioxide. The ability to metabolise L-malic acid is strain specific, and both individual Oenococcus oeni strains and other LAB strains vary in their ability to efficiently carry out MLF. Aside from impacts on acidity, LAB can also metabolise other precursors present in wine during fermentation and, therefore, alter the chemical composition of the wine resulting in an increased complexity of wine aroma and flavour. Recent research has focused on three main areas: enzymatic changes during MLF, safety of the final product and mechanisms of stress resistance. This review summarises the latest research and technological advances in the rapidly evolving study of MLF and investigates the directions that future research may take.

O risco das aminas biogênicas nos alimentos

Aminas biogênicas são bases orgânicas de baixo peso molecular com atividade biológica, produzidas a partir da ação da enzima descarboxilase. Microrganismos utilizados na fermentação de alimentos são capazes de produzi-las. O consumo desses compostos causam graves efeitos toxicológicos, indesejáveis para a saúde humana. Embora não exista legislação específica sobre a quantidade máxima permitida de aminas em alimentos e bebidas, a presença e o acumulo destes compostos é de grande importância. O objetivo desta revisão é evidenciar a necessidade de mais estudos e discutir a presença de aminas biogênicas em alimentos variados.