Process for stabilising of alcoholic drinks and precursors and derivatives thereof

Abstract

Process for the stabilizing of alcoholic drinks and precursors and derivatives thereof, consisting in adding thereto a solution containing polyglutamate and/or polyaspartate. The stabilization obtained is not only against tartrate precipitation, but also for colour stability and against oxidation. Such process basically provides the use of a composition containing polyglutamate, polyaspartate or a mixture of the two substances.

Claims

1. A process for the stabilizing of alcoholic drinks and precursors and derivatives thereof, consisting of adding thereto a composition containing polyaspartate.

2. The process as claimed in claim 1, wherein the alcoholic drink is selected from the group consisting of: wines, vermouth, liqueurs, beers, whiskey, and cider.

3. The process as claimed in claim 1, such wherein the precursor is selected from the group consisting of: fruit juices and musts.

4. The process as claimed in claim 1, such wherein the alcoholic drink derivative is vinegar.

5. The process as claimed in claim 1, wherein the polyaspartate possesses an average numeral molecular weight ranging between 1,000 and 30,000.

6. The process as claimed in claim 1, the composition concentration ranges between 1 and 100 g/hl.

7. The process as claimed in claim 1, characterized in that said composition is added after a finishing classifications.

Description

BEST WAY TO CARRY OUT THE INVENTION

(1) The present invention refers to a process for stabilising an alcoholic drink, such as wine, vermouth, liqueurs and the like, a precursor, typically a fruit juice or a must, or a derivative, such as typically vinegar. The stabilisation obtained is not only against tartrate precipitation, but also for colour stability and against oxidation. Such process basically provides the use of a composition containing polyglutamate, polyaspartate or a mixture of the two substances.

(2) These substances belong to the class of polyaminoacids, polymers the repeating unit of which is an aminoacid. These substances are perfectly biodegradable and non-toxic. Polyglutamate and polyaspartate are substances known per se. In particular, polyaspartate is used nowadays as a component of insecticides, fertilisers, detergents, as well as being an additive of cement, an anti-corrosion and limescale-removing agent. A particular use is in water treatment. However, neither of the two compounds employed according to the present invention has ever found application in the wine industry. Preferably, the average numeral molecular weight of such polyglutamates and polyaspartates ranges between 1,000 and 30,000.

(3) Without wanting to be bound to theory, it is believed that the stabilising action is due to the high charge density of the two compounds, such as to change the electrochemical balances of the solutions it is a component of. Furthermore, a chelating effect is assumed towards cations and positively-charged agents in wine, so that they are believed to reduce the ability to interact with negatively-charged molecules.

(4) The composition is added to the drink during the treatment thereof, before the final bottling.

(5) The present invention is now illustrated in greater detail, with reference to some examples. They refer to tartaric stability (examples 1, 2 and 3) and to colour stability (examples 3 and 4).

(6) The composition is added to the product to be treated so as to reach a concentration between 1 and 100 g/hl.

(7) If the composition is used in powder, it is added to a small amount of wine or of water, for example so as to obtain a 1:5 v/v dilution, agitating until full dissolution. The solution obtained is added to the liquid to be processed.

(8) If one starts from the liquid form, it is diluted in a small amount of wine or water (for example 1:5 v/v) until it is homogeneous and then it is added to the liquid to be processed.

(9) The addition is preferably made after the finishing classifications, a few days before bottling.

EXAMPLE 1

(10) Some samples of different wines, white and red ones, have been treated with a series of substances, adding 5 g or 10 grams, respectively, of a series of different stabilisers for each hectolitre of wine. Wines having high instability with respect to tartaric precipitation have been chosen, since such wines, before the treatment, have S/cm above 30. A value of S/cm below 20 is considered acceptable. As stabilisers, metatartaric acid (AMT), carboxymethylcellulose (CMC) and sodium polyaspartate (PAAaccording to the present invention) have been used. The results are reported in Table 1.

(11) TABLE-US-00001 TABLE 1 Stabilisation of some wines with different substances. Data in S/cm at 30 C. +5 +10 +5 +10 +5 +10 As g/hl g/hl g/hl g/hl g/hl g/hl Wine such AMT AMT CMC CMC PAA PAA Trebbiano 230 19 13 51 33 20 16 Chardonnay 146 14 12 28 22 15 10 Sangiovese 68 14 10 68 33 15 14 Cabernet 115 13 15 Trebbiano 230 21* 14* Verdicchio 126 135** 12** *The additives used have undergone a thermal treatment at 80 C. for 3 hours. **The additives used have undergone a thermal treatment at 40 C. for one day.

(12) It can be immediately noticed that the effectiveness of polyaspartate, the dosages being equal, is at least the same as that of metatartaric acid and greater than carboxymethylcellulose. Moreover, it is noticed that polyaspartate is more stable than metatartaric acid. As a matter of fact, when they undergo prolonged thermal treatment, the metatartaric acid tends to lose its properties, while polyaspartate maintains them, as can be seen from the last two table rows.

EXAMPLE 2

(13) In this example the filterability of a wine treated according to the present invention over an untreated wine is verified. The treated and untreated wine has been made to pass through a membrane with porosity 0.45 m, at a pressure of 2 bar and at a temperature of 20 C. The filterability index (T2-2T1, see below) and the modified filterability index [(T3-T1)-2(T2-T1)] are measured. A wine is considered filterable if the modified filterability index is below 10. The results are reported in Table 2.

(14) TABLE-US-00002 TABLE 2 Influence of polyaspartate addition on wine filterability Eluition time Eluition time for Chardonnay Filtered volume for untreated treated with 10 (ml) Chardonnay (s) g/hl of PAA (s) 100 23 23 200 T1 47 48 300 73 73 400 T2 98 98 500 125 125 600 T3 153 152 Filterability 4 2 index Modified filter- 4 4 ability index

(15) The experiment just reported shows that the addition of polyaspartate does not damage filterability, unlike what happens when carboxyimethylcellulose is added, which causesespecially in red winescolloidal instability phenomena and subsequent clogging of the filtering systems.

EXAMPLE 3

(16) This example highlights the stabilising properties both towards tartaric precipitation, and with regard to colour.

(17) A white wine and a red wine have been compared, assessing the possible formation of precipitates with no additions and with additions of crystallisation inhibitors. After the additions, the wines have been kept at 4 C. for 28 days. The results are reported in Table 3, where GA is gum arabic.

(18) TABLE-US-00003 TABLE 3 +10 g/hl +10 g/hl +10 g/hl Wine Wine as such PAA AMT GA Chardonnay Presence of No precipi- No precipi- No precipi- S/cm at tartrate tate tate tate 30 C. = 146 crystals Sangiovese Presence of No precipi- Deposit of Deposit of S/cm at tartrate tate colouring colouring 30 C. = 68 crystals and matter matter + colouring calcium matter tartrate- malate

(19) The experiment just described allows to see that, as far as Chardonnay is concerned, the stabilising effect of PAA is comparable to that of AMT and GA. In red wine, the stabilising effect of PAA is dramatically higher.

(20) Summary of the results of the experiments of tartraric stabilisation

(21) As seen, PAA, preventing ionswhich, however, remain present in solutionfrom salifying around precipitation nuclei until reaching a size which determine visual perception, allows to reach and maintain in time a high, virtually complete tartaric stability in red and white wines, without damaging the filterability and colour of the treated wines.

(22) The technique according to the present invention replaces with at least equal effectiveness, but usually with greater one, the practices already in use, is applicable in any type of manufacturing situation and has no contraindications from an environmental point of view.

(23) It must also be noted that the technique according to the present invention is not of a subtractive type, since it eliminates no wine component, maintaining the integrity thereof unchanged. The wine can be treated according to the present invention both during the processing steps and before the final packaging.

EXAMPLE 4

(24) A Portuguese red wine from Alentejo has been cold treated with polyaspartate, subjecting the sample to spectrophotometry, after filtration, in a 1-mm-thick cuvette.

(25) TABLE-US-00004 Data after cold testing Test 10 AMT 10 CMC 10 PAA 420 nm 4.03 3.84 3.3 3.9 520 nm 5.16 4.92 4 5.18 620 nm 1.09 1.03 0.83 1.06 IC (colouring 10.28 9.79 8.13 10.13 intensity) T (shade) 0.78 0.78 0.83 0.75 Change % D.O. 520 4.65 22.48 +0.39 nm compared to Test

(26) The cold test, 72 h at 4 C., is much more severe than the one which is normally used in wine cellars (24 hours at 0 C.) such test has been carried out that way to highlight the positive effect of PAA compared to the other tartaric stabilisation coadjuvants on antocyan balances also in extreme destabilising conditions.

(27) However, it is understood that the invention must not be considered limited to the particular examples illustrated earlier, which represent only an exemplifying embodiment threof, but that a number of modifications are possible, all within the reach of a person skilled in the field, without departing from the scope of protection of the invention, as defined in the following claims.