USE OF A YEAST EXTRACT FOR CLARIFYING MUSTS AND BEVERAGES

Abstract

The present invention relates to the use of a yeast extract including at least 10 wt % of nucleic acids, preferably at least 15 wt %, and more preferably 30 to 95 wt %, relative to the total weight of said extract, said nucleic acids being formed from fragments of ribonucleic acid (RNA), for clarifying musts and liquids, in particular wines and teas.

Claims

1. A method for clarifying musts and beverages chosen from wine, tea, beer and fruit juices, said method comprising contacting: a yeast extract comprising an amount by weight of nucleic acids of at least 10% relative to the total weight of said extract, said nucleic acids being formed from fragments of ribonucleic acid (RNA), with said musts and beverages.

2. A method as claimed in claim 1, wherein each of said fragments of RNA of the yeast extract has an average molecular weight of greater than 10 kDa.

3. A method as claimed in claim 1, wherein the yeast extract also comprises mineral materials, saccharides and free amino acids.

4. A method as claimed in claim 1, wherein the yeast extract is in the form of a powder or of a more or less concentrated liquid.

5. A method as claimed in claim 1, wherein the yeast of the extract is chosen from the group comprising Saccharomyces, Kluyveromyces, Torula and Candida.

6. A method as claimed in claim 1, for clarifying wines.

7. A method as claimed in claim 6, wherein the yeast extract is in the form of a powder and is used at a content ranging from 0.1 g (gram) to 50 g per hectoliter (hl) of wine.

8. A method as claimed in claim 1, for clarifying tea.

9. A method as claimed in claim 8, wherein the yeast extract is in the form of a powder and is used at a content ranging from 0.01 g (gram) to 5 g per liter (l) of tea.

10. A method for clarifying musts and beverages chosen from wine, tea, beer and fruit juices, said method comprising contacting: fragments of ribonucleic acid (RNA) originating from a yeast chosen from the group comprising Saccharomyces, Kluyveromyces, Torula and Candida and mixtures thereof, with said musts and beverages.

11. A method as claimed in claim 10, for precipitating the tannins and/or pigments present in tea.

12. A method as claimed in claim 1, wherein said yeast extract comprises an amount by weight of nucleic acids of 30% to 48% relative to the total weight of said extract.

13. A method as claimed in claim 2, wherein each of said fragments of RNA of the yeast extract has an average molecular weight from 30 to 110 kDa.

14. A method as claimed in claim 8, for precipitating the tannins and/or pigments from tea.

Description

[0069] The photos of FIGS. 1 and 2 illustrate the results, after 20 hours in a cold room, of the clarifying tests obtained with various clarifiers (respectively from left to right: Control, YPE, YNE30 and YNE95) on the wine A (FIG. 1) and the wine B (FIG. 2).

[0070] The photos of FIGS. 3, 4 and 5 illustrate the results, after 20 hours in a cold room, of the clarifying tests obtained with various clarifiers (respectively from left to right: Control, YPE, YPE/YNE30 and YNE30) on the CRUDE wine (FIG. 3), the wine A (FIG. 4) and the wine B (FIG. 5).

[0071] The photo of FIG. 6 illustrates the results of the clarifying test on the ice tea, and more particularly the results of the precipitation of the tannins from the ice tea, obtained after 18 hours at ambient temperature with the YNE30 clarifier at a concentration of 0.1 g/l.

[0072] The photos of FIG. 7 illustrate the results of the clarifying tests on the ice tea, and more particularly the results of precipitation of the tannins from the ice tea, obtained after 10 hours at a temperature of 6 C. (see respectively from left to right: Control (ice tea alone), YPE at a concentration of 1 g/l, YNE30 at a concentration of 0.3 g/l and YNE30 at a concentration of 1 g/l).

EXAMPLES 1 AND 2

Wine Clarifying Tests

[0073] The wines tested in examples 1 and 2 below are:

[0074] a crude wine (the most cloudy);

[0075] a wine A;

[0076] a wine B.

[0077] The products (clarifiers) tested are in powder form and are:

[0078] a yeast protein extract, represented by YPE, which serves as control (this YPE comprises in total approximately 13% of nucleotides and is described in Revue des nologues [Enologists' Review], No. 120; pages 47-50, 2006);

[0079] a yeast nucleic extract of the invention comprising 30% by weight of ribonucleic acid, represented by YNE30;

[0080] a yeast nucleic extract of the invention comprising 95% by weight of ribonucleic acid, represented by YNE95;

[0081] a sample consisting of 50% of YPE and of 50% of YNE30, represented by YPE/YNE30).

Example 1

Tube Tests

[0082] 1) A first series of clarifying tests in wine is carried out with the following clarifiers: YPE, YNE30 and YNE95 and on the following wines A (FIG. 1) and B (FIG. 2).

[0083] The clarifiers (in powder form) are incorporated at the maximum usable dose recommended for red wines or musts, namely 30 g of clarifier per hectoliter (hl) of wine/must.

[0084] The powders are pre-suspended diluted in 10 times their weight of water before incorporation into the wine. Thus, one gram (1 g) of clarifier is diluted in ten milliliters (10 ml) of distilled water.

[0085] An amount of thirty microliters (30 l) of each clarifier thus diluted is incorporated into a test tube (except the control tube) comprising 10 ml of wine/must tested.

[0086] The objective is to demonstrate the differences in clarifying efficiency of the various clarifiers used at the same concentration and on two different samples of wine.

[0087] The results obtained after a 20-hour residence time of the tubes in a cold room (approximately+4 C.) are illustrated in FIGS. 1 (for the wine A) and 2 (for the wine B).

[0088] The bigger the decanting pellet observed in the test tube (i.e. the greater the decanting), the more satisfactory the clarifying.

[0089] The photos of FIGS. 1 and 2 show that, in the two cases, the control does not give a pellet since there is no natural decanting.

[0090] On the other hand, in the tubes comprising the clarifiers of the invention (YNE30 and YNE95), a decanting pellet is observed that is much larger (regardless of the wine tested) than in the tube comprising the prior art clarifier (YPE), which makes it possible to demonstrate better clarifying of the wine with the clarifiers of the invention compared with the prior art clarifier.

[0091] 2) A second series of clarifying tests in wine is carried out with the following clarifiers: YPE, YPE/YNE30 and YNE30, on the crude wine (FIG. 3), the wine A (FIG. 4) and the wine B (FIG. 5).

[0092] The clarifiers are prepared at the same concentration (30 g/hl) as described in section 1) above.

[0093] The results obtained after a 20-hour residence time of the tubes in a cold room (approximately +4 C.) are illustrated in FIGS. 3 (crude wine), 4 (wine A) and 5 (wine B).

[0094] The photos of FIGS. 3 to 5 show that, in the three cases, the control does not show a pellet (no natural decanting).

[0095] The largest decanting pellet is observed with the YNE30 clarifier of the invention, regardless of the wine tested (FIGS. 3 to 5).

[0096] A larger decanting pellet is also observed with the YPE/YNE30 clarifier mixture than with the YPE prior art clarifier, regardless of the wine tested (FIGS. 3 to 5).

[0097] Thus, when a clarifier comprising a mixture of a clarifier of the invention and a clarifier of the prior art is prepared, this mixture makes it possible to improve the clarifying obtained with the clarifier of the prior art alone, not mixed with the clarifier of the invention.

3) Conclusion

[0098] The tests above demonstrate that the nucleic yeast extracts of the invention are clarifiers which are much more efficient for wines than the YPE natural clarifier of the prior art.

[0099] Moreover, the yeast nucleic extract of the invention has the important advantage of being simpler to produce than the YPE and of not requiring complex facilities.

Example 2

Spectro Cuvette Tests

[0100] Turbidity tests were carried out directly in a spectro cuvette.

[0101] As a reminder, turbidity, expressed in NTU (Nephelometric Turbidity Units), denotes the content of a fluid in terms of matter which makes it cloudy.

[0102] The YNE30 and YNE95 clarifiers of the invention are prepared at three different concentrations: 10 g/hl, 20 g/hl and 30 g/hl, by means of a prior dilution of each clarifier in distilled water (see previous example), followed by addition to the wine B.

[0103] The initial turbidity of the wine B is 127 NTU.

[0104] The turbidity of said wine to which the clarifiers of the invention at various concentrations were added is measured after 48 hours in a cold room (+4 C.)

[0105] The results are given in table 1 below.

TABLE-US-00001 TABLE 1 Clarifier Clarifier Clarifier Wine B 10 g/hl 20 g/hl 30 g/hl YNE95 127 NTU 9.9 NTU 10.2 NTU 8.8 NTU YNE30 127 NTU 10.2 NTU 11 NTU 10.7 NTU

[0106] The decrease in the turbidity is significant, for each of the two clarifiers, and regardless of their concentrations. The YNE95 and YNE30 clarifiers of the invention are each already very active at a concentration of 10 g/hl (decrease in the turbidity by a factor of 12).

[0107] A virtually identical clarification of the supernatants is noted after 48 hours, regardless of the concentration of the clarifiers of the invention.

[0108] The yeast extracts of the invention, rich in RNA, are thus very efficient as clarifiers in the wine sector.

EXAMPLE 3

Tea Clarifying Tests

[0109] The tea tested in this example is ice tea.

[0110] The objective of this example is to demonstrate, on the one hand, the precipitation of the tannins from the tea (which are found in the decanting pellet) and, on the other hand, the change in color of the tea.

[0111] The clarifier tested is in powder form and is YNE30.

[0112] Three samples having different concentrations are prepared, namely 0.1 g of YNE30 per liter of tea and 0.3 g of YNE30 per liter of tea and 1 g of YNE30 per liter of tea.

[0113] The powder is diluted beforehand in 10 times its weight of water. Thus, one gram of powder is diluted in 10 ml of distilled water.

[0114] The powder is totally soluble in the water; it is thus a clear solution that is added to the tea.

1) Test at Ambient Temperature

[0115] The YNE30 is introduced into a tube comprising ice tea (concentration prepared=0.1 g/l). The results obtained after 18 hours at ambient temperature are shown in FIG. 6.

[0116] The formation of a decanting pellet and a slight decoloration of the tea are observed.

[0117] The decanting pellet is removed using a pipette and is tasted by 3 individuals, including a flavorist.

[0118] The sensation noticed by each of the testers is astringency.

[0119] Since the sensation of astringency is provided by the tannins, it can be concluded from this that there has been good precipitation of the latter in the decanting pellet.

2) Test at 6 C.

[0120] The following four samples were tested:

[0121] ice tea alone (control),

[0122] ice tea into which has been introduced YPE at a concentration of 1 g/l,

[0123] ice tea into which has been introduced YNE 30 at a concentration of 0.3 g/l,

[0124] ice tea into which has been introduced YNE 30 at a concentration of 1 g/l.

[0125] The results obtained after 10 hours at 6 C. are shown in FIG. 7.

[0126] The 4 samples described above are respectively represented from left to right in FIG. 7 (thus, the sample on the far left is the control, the one next to it is the one into which YPE has been introduced, etc.).

[0127] For the ice tea alone, no decanting or decoloration is observed.

[0128] For the ice tea into which has been introduced YPE (1 g/l), decanting and slight decoloration are observed after 2 to 3 months (as a reminder, FIG. 7 shows the results after 10 hours, therefore no decanting or decoloring observed), whereas, with the ice tea into which has been introduced YNE (at 0.3 and 1 g/l), a clear decanting and decoloring are observed after 3 to 6 hours.

[0129] The decanting pellet was removed by using a pipette and was tasted by the 3 testers mentioned in point 1 above.

[0130] The sensation noticed by each tester in terms of astringency is evaluated in table 2 below.

TABLE-US-00002 TABLE 2 Ice tea + Ice tea Ice tea + 0.3 g/l Ice tea + as is 1 g/l YPE YNE 1 g/l YNE Decanting None 2-3 months 3-6 hours 3-6 hours and decoloring Temperature 6 C. 6 C. 6 C. 6 C. Tasting of the 0 3 3 5 precipitation pellet: Sensation of astringency

[0131] The sensation of astringency is slightly higher for the decanting pellet in the tube to which was added the YNE30 at a concentration of 0.3 g/l, compared with that felt by the tester for the decanting pellet in the tube to which was added the YNE30 at a concentration of 1 g/l.

Conclusion

[0132] After 10 hours, no difference was observed between the control sample (ice tea alone) and that to which was added the YPE at a concentration of 1 g/l. The addition of YPE to the ice tea does not make it possible to produce the precipitation of the tannins from the tea and/or the precipitation of the pigments from the tea.

[0133] On the other hand, the addition of YNE30 at concentrations such as 0.3 g/l or 1 g/l is sufficient to induce the precipitation of the tannins from the tea and of the pigments from the tea, this starting from 3 to 6 hours after the addition of YNE. The decoloring of the ice tea is clear for the tubes to which was added YNE30, regardless of the YNE concentration.

[0134] The addition of YNE30 at a concentration of 1 g/l to the ice tea results in a decanting pellet that is larger than with the addition of YNE30 at a concentration of 0.3 g/l.

[0135] Moreover, the sensation in terms of astringency is higher for the decanting pellet in the tube to which was added YNE at 1 g/l.

[0136] Since the sensation of astringency is provided by the tannins, it can be concluded from this that there has been good precipitation of the latter in the decanting pellet.