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 wine clarification method for clarifying cloudy wine having an unstable-particle load and comprising particles, wherein the particles are due to protein degradation or to microbiological growth, said method comprising flocculating and precipitating the particles in the wine, comprising contacting the wine comprising the particles with a yeast nucleic acids extract, wherein the yeast nucleic acids extract comprises ribonucleic acid (RNA) molecules in an amount by weight of 30% to 48% relative to the total weight of said yeast nucleic acids extract, wherein said RNA molecules of the yeast nucleic acids extract have an average molecular weight of greater than 10 kDa, and wherein said contacting results in flocculating and precipitating the particles and whereby the wine is clarified.

2. The method as claimed in claim 1, wherein the yeast nucleic acids extract additionally comprises mineral materials, saccharides, and free amino acids.

3. The method as claimed in claim 1, wherein the yeast nucleic acids extract is in a form comprising a powder or a concentrated liquid.

4. The method as claimed in claim 1, wherein yeast of the yeast nucleic acids extract comprises Saccharomyces, Kluyveromyces, Torula or Candida.

5. The method as claimed in claim 1, wherein the yeast nucleic acids extract is in the a form of comprising a powder and the contacting comprises adding from 0.1 g (gram) to 50 g of the yeast nucleic acids extract per hectoliter (h1) of wine.

6. The method as claimed in claim 1, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

7. The method as claimed in claim 4, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

8. The method as claimed in claim 1, wherein the yeast nucleic acids extract is a product of a plasmolysis.

9. The method as claimed in claim 1, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

10. The method as claimed in claim 2, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

11. The method as claimed in claim 3, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

12. The method as claimed in claim 5, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

13. The method as claimed in claim 8, wherein each of the molecules of RNA of the yeast nucleic acids extract has an average molecular weight from 30 to 110 kDa.

Description

(1) 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).

(2) 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).

(3) 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.

(4) 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

(5) The wines tested in examples 1 and 2 below are:

(6) a “crude” wine (the most cloudy);

(7) a wine “A”;

(8) a wine “B”.

(9) The products (clarifiers) tested are in powder form and are:

(10) 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 œnologues” [“Enologists' Review”], No. 120; pages 47-50, 2006);

(11) a yeast nucleic extract of the invention comprising 30% by weight of ribonucleic acid, represented by “YNE30”;

(12) a yeast nucleic extract of the invention comprising 95% by weight of ribonucleic acid, represented by “YNE95”;

(13) a sample consisting of 50% of YPE and of 50% of YNE30, represented by “YPE/YNE30”).

Example 1

Tube Tests

(14) 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).

(15) 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.

(16) 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.

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

(18) 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.

(19) 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).

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

(21) 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.

(22) 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.

(23) 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).

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

(25) 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).

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

(27) The largest decanting pellet is observed with the “YNE30” clarifier of the invention, regardless of the wine tested (FIGS. 3 to 5).

(28) 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).

(29) 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

(30) 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.

(31) 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

(32) Turbidity tests were carried out directly in a spectro cuvette.

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

(34) 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”.

(35) The initial turbidity of the wine “B” is 127 NTU.

(36) 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.)

(37) The results are given in table 1 below.

(38) 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

(39) 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).

(40) A virtually identical clarification of the supernatants is noted after 48 hours, regardless of the concentration of the clarifiers of the invention.

(41) The yeast extracts of the invention, rich in RNA, are thus very efficient as clarifiers in the wine sector.

EXAMPLE 3

Tea Clarifying Tests

(42) The tea tested in this example is ice tea.

(43) 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.

(44) The clarifier tested is in powder form and is YNE30.

(45) 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.

(46) 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.

(47) 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

(48) 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.

(49) The formation of a decanting pellet and a slight decoloration of the tea are observed.

(50) The decanting pellet is removed using a pipette and is tasted by 3 individuals, including a flavorist.

(51) The sensation noticed by each of the testers is astringency.

(52) 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.

(53) The following four samples were tested:

(54) ice tea alone (control),

(55) ice tea into which has been introduced YPE at a concentration of 1 g/l,

(56) ice tea into which has been introduced YNE 30 at a concentration of 0.3 g/l.

(57) ice tea into which has been introduced YNE 30 at a concentration of 1 g/l.

(58) The results obtained after 10 hours at 6° C. are shown in FIG. 7.

(59) 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.).

(60) For the ice tea alone, no decanting or decoloration is observed.

(61) 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.

(62) The decanting pellet was removed by using a pipette and was tasted by the 3 testers mentioned in point 1 above.

(63) The sensation noticed by each tester in terms of astringency is evaluated in table 2 below.

(64) 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

(65) 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

(66) 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.

(67) 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.

(68) 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.

(69) 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.

(70) 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.