BOISSON FERMENTEE

FERMENTED DRINK

Abrégé français

Procédé pour la préparation d'une boisson fermentée contenant un extrait aqueux préparé à partir d'une solution de thé ou de café à 0,5-2 %; l'extrait aqueux, auquel du sucre est ajouté, est récupéré et une fermentation à une ou plusieurs étapes est amorcée à l'aide d'au moins une souche de levure et d'au moins une souche bactérienne; les éléments insolubles sont enlevés de la boisson fermentée, qui est ensuite chauffée. L'invention renvoie aussi à la boisson fermentée ainsi obtenue.

Abrégé anglais

Process for the preparation of a fermented
drink in which an aqueous extract is prepared from 0.5-
2% tea or coffee, the aqueous extract, to which sugar
is added, is recovered and a fermentation is carried
out in one or more stages with at least one yeast
strain and at least one bacterial strain, the
insolubles are separated from the fermented drink and
then it is heat-treated.
The invention also relates to the fermented
drink obtained using the process.

Revendications

-9-
Claims
1. Process for the preparation of a fermented drink, in
which:
- an aqueous extract is prepared from 0.5-2% tea or coffee,
- 4-13% sugar is added to this extract,
- a fermentation is carried out in one or more stages with
at least one yeast strain and at least one bacterial strain in a
fermenter under a relative pressure of 50-80 kPa while stirring and
aerating,
- the insolubles are separated from the fermented drink,
- and then the fermented drink is heat-treated at 85-140°C
for 30 s to 15 min.
2. Process according to Claim 1, in which the aqueous
extract is prepared from 0.5-2% black or green tea which is infused in
boiling water for 3-30 min.
3. Process according to Claim 1, in which the said
fermentation is carried out in a single stage by inoculating a yeast
strain and a bacterial strain into the aqueous extract simultaneously,
under aerobic conditions, at 27-32°C for 2-10 h.
4. Process according to Claim 2, in which the pH of the
said aqueous extract is adjusted to a value of 4 to 5.5 before the
fermentation.
5. Process according to Claim 1, in which the said
fermentation is carried out under aerobic conditions in two stages by
inoculating into the aqueous extract first of all a yeast strain at 27-
32°C, for 15-27 h, and then by inoculating into the aqueous extract a
bacterial strain at 20-32°C for 3-9 h.

-10-
6 . Process according to Claim 3, in which the temperature
of the medium is adjusted to 17-25°C before inoculating the bacterial
strain.
7. Process according to Claim 1, in which 0.02 - 0.2% of
a culture containing 10 7 to 10 10 cells of a yeast strain is inoculated
into the aqueous extract for the fermentation in one or more stages.
8. Process according to Claim 1, in which 0.2-1.5% of a
culture containing 10 7 to 10 9 cells of a bacterial strain is inoculated
into the aqueous extract for the fermentation in one or more stages.
9. Process according to Claim 1, in which the temperature
is decreased to 0-12°C at the end of the fermentation.
10. Fermented drink obtained by the process according to
one of Claims 1-9.

Description

2197¢81
' Fermented drink
-
The subject of the present invention is a pro-
cess for the preparation of a fenmented drink as well
as the fermented drink obtained by this process.
The preparation of fermented drinks, especially
tea fermented by a yeast strain and/or a bacterial
strain, has been known for a long time.
Traditionally, the fermentation of tea occurs
at the surface for about ten days or even longer. The
mother is of variable composition; it contains
especially polysaccharides and rapidly increases until
it becomes cl~m~ersome. Accordingly, by using a tradi-
tional process, it is not possible to produce a fer-
mented tea in large quantities.
Deutsche Leben~;ttel-Rundschau, 83, 286-290,
1987 describes a process for the preparation of fer-
mented drinks, especially a fermented black tea, in
which a fermentation is carried out in a single stage
from a black tea filtrate by a yeast strain, especially
a Schizosaccharomyces pombe strain, and a bacterial
strain, especially an Acetobacter xylinum strain, for
six days, BO as to obtain a drink with a plea~ant
taste. The fermentation does not occur at the surface
but has the disadvantage of being relati~ely long.
The aim of the present in~ention is to pro~ide
a process for the preparation of a fermented drink
under particularly simple conditions and in a rela-
tively short preparation time thus allowing the produc-
tion of a fermented drink in large quantities.
To this end, in the process for the preparationof a fermented drink according to the present inven-
tion:
- an aqueous extract is prepared from 0.5-2% tea or
coffee,
- 4-13% sugar is added to this extract,
- a fermentation is carried out in one or more stages
with at least one yeast strain and at least one
bacterial strain,

2 1 9 748 1
-- 2
- the insolubles are separated from the fermented
drink,
- and then it is heat-treated at 85-140~C for 30 s to
15 min.
It was observed, surprisingly, that such a
process effectively makes it possible to produce, in
large quantities, a fermented drink with a pleasant
taste in a short preparation time.
To carry out the present process, an aqueous
extract i8 therefore prepared from 0.5-2% tea or
coffee.
If the aqueous extract i8 prepared from tea,
0.5-2% black or green tea may be infused in boiling
water for 3-30 min for exa~ple. To do thi~, the tea may
be infused in a filter bag immersed in boiling water
for example. But it is also possible to infuse the tea
directly in boiling water and then to carry out a
centrifugation or a filtration so as to separate the
insolubles from the aqueous extract for example.
If the aqueous extract is prepared from coffee,
0.5-2% soluble coffee may be diluted in boiling water
for ex~mple.
Preferably, 4-13% sugar, especially sucrose, is
added to the aqueous extract as substrate for the
fermentation by at least one yeast strain.
There may be inoculated into the aqueous
extract, for the fermentation in one or more stages,
0.02-0.2% of a culture con~;nin~ 107 to 101~ cells of a
yeast strain, especially a Saccharomyces cere~isiae
strain, 80 as to produce ethanol, and 0.2-1.5% of a
culture cont~;n;n~ 107 to 109 cells of a bacterial
strain, especially an Acetobacter strain or a Glucono-
bacter strain, 80 as to acidify the aqueous extract.
For the fermentation by at least one yeast
strain, there may be used as S~c~h~romyces cere~isiae
strain that marketed under the name DCL Spady by The
Distillers Company L;m~ted~ Collingwood House, Sutton,
Surrey SM3 AT England or that marketed under the name

21974~1
Castelli by Laboratorio Zimotecnico Italiano, via dei
-
Setti Santi 28, IT-Florence, for example.
For the fermentation by at least one bacterial
strain, there may be used especially the Acetobacter
strain deposited on 16 January 1996, in accordance with
the Budapest treaty, at the Collection Nationale de
Microorganismes, lN~'Ll'lU'L PASTEUR, 25 Rue du Docteur
Roux, F-75724 PARIS CEDEX 15, France, where it received
the deposit number CNCM I-1656. It is also possible to
use the Gluconoh~~ter suboxydans strain accessible at
the Collection D~ul~ SAMMLUNG VON MIKROORGANISMEN,
DE-R~ SCHEIG, where it received the deposit number
DSM 50049 for example.
The fermentation may be carried out in a
fermenter under a relative pressure of-50-80 kPa for
example. There may be used as fermenter in particular a
fermenter of the PAC type - APP fermenter No. 9-273-
300-68, marketed by Chemap SA, CR-8604 VOLRETSWIL.
The fermentation may also be carried out in a
simple open tank for example.
In a first preferred embodiment of the process
according to the present invention, there is inoculated
into the aqueous extract simultaneously a yeast strain
and a bacterial strain and the fermentation is carried
out in a single stage under aerobic conditions, at 27-
32~C for 2-10 h.
Preferably, the pH of the aqueous extract is
adjusted to a value of 4 to 5.5 before the fermen-
tation, 80 as to facilitate the fermentation by a yeast
strain.
In a second preferred embodiment of the process
according to the present invention, the fermentation is
carried out under aerobic conditions in two stages. To
do this, a yeast strain is first of all inoculated into
the aqueous extract and the fermentation i8 allowed to
proceed at 27-32~C, for 15-27 h. Then a bacterial
strain is inoculated into the aqueous extract and the
fermentation is allowed to proceed at 20-32~C for
3-9 h.

21 97481
- 4 -
Preferably, the temperature of the medium is
adjusted to 17-25~C before inoculating the bacterial
strain, so as to slow down the formation of ethanol due
to the fermentation by the yeast strain.
5At the end of the fermentation in one or more
stages, the temperature may be decreased to 0-12~C, so
as to reduce the production of ethanol due to the
fermentation by the yeast strain and the acidification
due to the fermentation by the bacterial strain for
example.
Then the insolubles may be separated from the
fermented drink by centrifugation or by filtration for
example.
Preferably, the fermented drink is then heat-
15treated at 85-140~C for 30 8 to 15 min, so as to
inactivate the yeasts and the bacteria and to eliminate
all the pathogenic agents.
The subject of the present in~ention is also
the fermented drink obt~ine~ uging the said process.
20The process for the preparation of a fermented
drink according to the present invention is described
in greater detail in the non-limiting examples below.
In these examples, the percentages and parts are given
by weight, unless otherwise indicated. The measurements
of the ethanol content and of the acetic acid content
of the said fermented drinks were obtained by the
BohringertR) method of enzymatic measurement. Further-
more, the pH was measured with electrodes.
Example 1
Fermented tea is prepared.
In a simple open tank, 1% green tea is infused
in boiling water for 10 min. To do this, a filter bag
cont~;n;ng 1.2 kg of green tea is immersed in boiling
water.
The filter bag is removed and 11% sucrose is
added to the aqueous extract whose temperature has been
pre~iously adjusted to 30~C.

21 ~748 1
-- 5
The fermentation is carried out in two stages.
To this end, 0.1% of a culture cont~;ning 10 cells of
Saccharomyces cerevisiae Castelli strain is first of
all inoculated into the aqueous extract and the fermen-
tation is allowed to proceed at 30~C for 19 h. The tem-
perature of the aqueous extract is decreased to 20~C,
before inoculating into the aqueous extract 1% of a
culture cont~in;ng 108 cells of the Acetobacter strain
CNCM I-1656 and the fermentation is allowed to proceed
at 20~C for 7 h, while stirring and aerating, so as to
provide a supply of oxygen.
At the end of the fermentation, the temperature
of the aqueous extract i~ decreased to 5~C.
- Then the fermented tea is isolated by
separating the insolubles by filtration.
Finally, the fermented tea which has been
- -prepacked is sterilized at 140~C for 40 s.
A fermented tea with an apple-like taste is
thus obtained which has a pH of 3.4 and has an ethanol
content of 0.32% and an acetic acid content of 0.36%.
Example 2
Fermented tea is prepared.
In a simple open tank, 1% green tea is infused
in boiling water for 20 min. To do this, a filter bag
cont~; n; ng 1. 2 kg of green tea is ;mmersed in boiling
water.
The filter bag is removed and 7% sucrose is
added to the aqueous extract whose temperature has been
previously adjusted to 30~C.
The fermentation i~ carried out in a single
stage. To do this, before the fermentation, the pH of
the aqueous extract is adju~ted to 5 and then 0.05% of
a culture contA;n;ng 108 cells of the Saccharomyces
cerevisiae Castelli strain and 0.5% of a culture con-
t~;n;ng 10 cells of the Gl~cQnoh~cter Ruboxydans
strain DSM 50049 are inoculated into the aqueous
extract simultaneou~ly and the fermentation is allowed

~ - 6 - 2 1 ~ 7 ~ 8 1
to proceed at 30~C for 7 h, while stirring and
aerating, 80 as to provide a supply of oxygen.
At the end of the fermentation, the temperature
of the aqueous extract is decreased to 5~C.
Then, the fermented tea is isolated by separat-
ing the insolubles by filtration.
Finally, the fermented tea which has been
prepacked is pasteurized at 95~C for 5 min.
A sweet fermented tea with an apple-like taste
is thus obt~;ne~ whi~h has a pH of 4.47 and has an
ethanol content of 0.05% and an acetic acid content of
0.032%.
Example 3
The procedure i8 carried out in the ~-nn~r
described in Example 2, except for the fact that during
the fermentation stage, 0.05% of a culture cont~in;ng
108 cells of Saccharomyces cere~isiae Spady strain and
0.5% of a culture cont~;n;ng 10 cells of the Glucono-
bacter suboxydans strain DSM 50049 are inoculated.
A fer_ented tea with an apple-like taste is
thus obtained which has a pH of 4.45 and has an acetic
acid content of 0.05%. The said fermented tea contains
ethanol in trace amounts.
Example 4
1% green tea i8 infused in boiling water for
10 _in. To do this, a filter bag cont~;n;ng 1.2 kg of
tea i8 immersed in boiling water.
The filter bag is L~ ,v~d and the aqueous
extract, to which 11% sucrose i8 added, is collected in
a fermenter of the PAC type - APP fermenter No. 9-273-
300-68, _arketed by Ch~m~p SA, CH-8604 VOLRETSWIL.
The fermentation is carried out in two stages.
To this end, the t~m~erature of the fermenter is
adjusted to 30~C. The pressure is adjusted to 60 kPa so
as to ha~e an oxygen concentration of 10 mg/l in the
fermentation medium. The injection of air into the
fermentation medium is adjusted to 1000 l/h so as to

21~14(3~
maintain a stable oxygen concentration. Finally, the
stirring of the fenmentation medium is adjusted to
400 rpm so that the whole of the aqueous extract is
properly oxygenated during the fermentation.
Under these conditions, 0.1% of a culture con-
t~in;ng 108 cells of a Saccharomyces cerevisiae
Castelli strain is inoculated into the aqueous extract
and the fermentation is allowed to proceed at 30~C for
19 h. Then the temperature of the aqueous extract is
decreased to 20~C and the pressure is adjusted to
70 kPa, before inoculating into the aqueous extract 1%
of a culture cont~;n;n~ 10 cells of an Acetobacter
strain CNCM I-1656 for 7 h.
At the end of the fermentation, the temperature
of the aqueous extract iB decreased to 5~C.
Then the fermented tea iB isolated by separat-
ing the insolubles by filtration.
Finally, the fermented tea which has been
prepacked is sterilized at 140~C for 40 s.
A fermented tea with an apple-like taste is
thus obt~; neA~ which has a p~ of 3.4 and has an ethanol
content of 0.32% and an acetic acid content of 0.36%.
Example 5
Fermented coffee is prepared.
To do this, 1% soluble coffee is diluted in
boiling water.
The temperature of the aqueous extract is
adjusted to 30~C before ~AAing 5% sucrose thereto.
The fermentation i8 carried out in a 6ingle
stage. To do this, before the fermentation, the pH of
the aqueous extract is adjusted to 5 and then 0.05% of
a culture cont~;ning 108 cells of Saccharomyces
cere~isiae Castelli and 0.5% of a culture cont~;n;ng
10 cells of the Acetobacter strain CNCM I-1656 are
inoculated into the aqueous extract simultaneously and
the fermentation is allowed to proceed at 30~C for 7 h,
while stirring and aerating, so as to pro~ide a supply
of oxygen.

8 2 1 9748 1
At the end of the fermentation, the temperature
of the aqueous extract i8 decreased to 5~C.
Then the fermented coffee is isolated by
separating the insolubles by filtration.
5Finally, the fermented coffee which has been
prepacked is pasteurized at 95~C for 5 min.
A fermented coffee with a fruity taste is thus
obtained which has a p~ of 4.31 and has an acid content
of O.03%. The said fermented coffee contains ethanol in
lC trace amounts.