EP-4736661-A1 - METHOD FOR PREPARING A FERMENTED BEVERAGE AND FERMENTED BEVERAGE PRODUCED BY SAID METHOD

Abstract

The invention relates to a method of preparing a fermented beverage from tea or rooibos together with a carbon source, which contemplates the sequential addition of a lactic acid bacterium and a yeast, such that two independent fermentations occur with a simplified microbial consortium, whereas the claimed method has a duration of less than 7 days. Advantageously, the method of the invention allows manufacturing times to be reduced, and the characteristics of the beverage obtained to be personalised in an optimal manner. The fermented beverage obtained is also an object of the invention.

Inventors

• PORCAR MIRALLES, Manuel
• VILANOVA SERRADOR, Cristina
• Gimeno Valero, Helena
• Borrego Piquer, Marta
• Sanz López, Carmen

Assignees

• Darwin Bioprospecting Excellence S.L.

Dates

Publication Date

20260506

Application Date

20240619

Claims (15)

1. A method of preparing a fermented beverage comprising the steps of: - preparing a mixture of a tea or rooibos infusion and a carbon source to obtain a must, - adding at least one lactic acid bacterium for food use (GRAS/QPS) and fermenting for at least one day for the partial consumption of the carbon source and the production of organic molecules by the lactic acid bacterium, - adding a yeast for food use (GRAS/QPS) and fermenting for at least one day for the partial consumption of carbon by the yeast, generating CO 2 and alcohol, characterised in that the steps described in detail take place in a biorreactor with a free exit of fermentation gas, such that the fermentation caused by the lactic acid bacterium and the fermentation caused by the yeast are carried out openly and take place sequentially, being independent steps, whereas the steps of the fermentation method take place in less than 7 days, allowing a fermented beverage with a pH between 2.5 and 4.5 to be obtained.
2. The method of preparing a fermented beverage according to claim 1, characterised in that the addition of the lactic acid bacterium takes place before the addition of the yeast, such that fermentation with the lactic acid bacterium takes place before fermentation with the yeast.
3. The method of preparing a fermented beverage according to claim 1, characterised in that the addition of the yeast takes place before the addition of the lactic acid bacterium, such that fermentation with the yeast takes place before fermentation with the lactic acid bacterium.
4. The method of preparing a fermented beverage according to any of the preceding claims, characterised in that the biorreactor is provided with aeration means.
5. The method of preparing a fermented beverage according to any of the preceding claims, characterised in that the fermented beverage is taken to a closed container where a third fermentation takes place.
6. The method of preparing a fermented beverage according to claim 1, characterised in that the carbon source is honey or sugar.
7. The method of preparing a fermented beverage according to claim 1, characterised in that the tea is green tea.
8. The method of preparing a fermented beverage according to claim 1, characterised in that after the open fermentations, a sweetener, preferably xylitol, aspartame, erythritol, or steviol, is added.
9. The method of preparing a fermented beverage according to claim 1, characterised in that after the open fermentations, carbon dioxide is added.
10. The method of preparing a fermented beverage according to claim 1, characterised in that vinegar, long-fermented kombucha, and/or acetic acid is added.
11. The method of preparing a fermented beverage according to claim 1, characterised in that the bacterium used is preferably chosen from Lactiplantibacillus plantarum, Lactiplantibacillus paraplantarum, Levilactobacillus brevis, Lacticaseibacillus paracasei, Lacticaseibacillus casei, Pediococcus pentosaceus, and/or Pediococcus acidilactici.
12. The method of preparing a fermented beverage according to claim 1, characterised in that the added yeast is preferably chosen from Saccharomyces spp, Bretanomyces, Zygosaccharomyces, Torulaspora, Lachancea, and / or Kluyveromyces.
13. The method of preparing a fermented beverage according to claim 1, characterised in that flavouring are added, preferably: aromas, plant extracts, and/or spices.
14. The method of preparing a fermented beverage according to claim 1, characterised in that probiotic microorganisms, preferably microorganisms from the genus Bacillus, are added after the open fermentations.
15. A fermented beverage obtained according to the method described in any of the preceding claims, characterised in that it has a pH between 2.5 and 4.5.

Description

OBJECT OF THE INVENTION The present invention relates to a method of preparing a fermented beverage, as well as to the fermented beverage obtained by said method. Namely, the method of the invention is based on a controlled and sequential fermentation from tea or rooibos using a simplified microbial consortium based on at least one bacterium and one yeast, which advantageously allows manufacturing times to be reduced to times of less than 7 days, and guarantees that the quality and characteristics of the fermented beverage obtained are fully reproducible. BACKGROUND OF THE INVENTION Beverages obtained from an infusion or plant extract in which fermentation is carried out and which are particularly advantageous from a nutritional and organoleptic viewpoint are known in the state of the art. Namely, fermented beverages of the kombucha family are known, which beverages are usually produced by means of fermenting black tea sweetened with sugar (or sweetened with honey or another type of sugary solution) with a complex microbial consortium of bacteria and yeasts that form a thick gelatinous-looking layer known as SCOBY (an acronym for Symbiotic Consortium of Bacteria and Yeast). As mentioned above, said consortium is a complex combination of bacterial species (mainly acetic, but also lactic) and yeasts. Although the organoleptic properties of kombucha can vary greatly depending on the fermentation time, in general it is a beverage with a vinegary flavour due to the production of acetic acid. Another example of well-known beverages of this type is jun, which is made from green tea instead of black tea and honey instead of sugar, resulting in a more bubbly and less acidic beverage than kombucha. In the case of jun, fermentation is also carried out by a complex SCOBY in which acetic fermentation predominates. The complexity of the microbial community of the SCOBY used to obtain known fermented beverages results in the difficulty of standardising these beverages and, therefore, producing them on an industrial scale, as fermentation times are long (2-4 weeks) and fermentation is not easily reproducible, with large variations in the duration, acidity, sugar content, alcohol, or flavour of the end product. Additionally, known fermented beverages have high acidity, so in order for them to be accepted by certain consumers, it is necessary to incorporate a high content of sugar, sweetener, or the like, which detracts from the quality of the beverage obtained. Thus, the applicant for the present invention recognises the need to develop a simplified method in terms of the consortium of microorganisms used and the production time, which allows for the precise and reproducible selection of the characteristics of the fermented beverage obtained for its industrial-scale production. DESCRIPTION OF THE INVENTION The method described below solves the drawbacks set forth above, such that it enables a fermented beverage to be obtained with the desired parameters in a minimum amount of time and with reproducible characteristics, facilitating its industrial production. To that end, the method developed in the present invention is based on a controlled and sequential fermentation of a tea, a rooibos, or the like, using to that end a simplified microbial consortium made up of at least one bacterium and at least one yeast, based on the steps described below: Preparing a mixture of a tea, preferably green tea (although it could be any other type of tea) or rooibos infusion and a carbon source, such as sugar or honey, to obtain a must. It should be noted that the carbon source is a compound containing carbohydrates, such as refined sugar, cane sugar, or honey.Adding or inoculating at least one lactic acid bacterium for food use (GRAS/QPS) and fermenting for at least one day for the partial consumption of carbon by the lactic acid bacterium and the production of organic molecules, providing aromas, flavours, lactic acidity, etc. In the context of the present invention, GRAS/QPS refers to microbial safety standards, where GRAS is the acronym for 'Generally Recognised As Safe' used by the US FDA (Food and Drug Administration) to classify microorganisms considered safe from the food viewpoint, whereas QPS is the acronym for 'Qualified Presumption of Safety' used by the EFSA (European Food Safety Authority).Adding or inoculating a yeast for food use (GRAS/QPS) and fermenting for at least one day for the partial consumption of carbon by the yeast, generating an amount of CO2 and alcohol and providing aromas, flavours, and acidity. In this sense, the steps described in detail take place in a biorreactor or fermenter with a free exit of fermentation gas, such that the two steps of fermentation described in detail are carried out openly. Preferably, the biorreactor is provided with aeration means which allow the culture to be kept under optimal conditions for fermentation. Additionally, it should be noted that, unlike the known processes for obtain