Impregnated wood chip, wood chip impregnation method and use thereof

Abstract

The present invention relates to a novel method of impregnating wood, as well as wood chips to be subsequently used for wine aging. The wood chips are impregnated with a liquid food product or a dry residue of the liquid food product.

Description

[0001] This invention relates to a novel method for impregnating wood, or to impregnated wood that will subsequently be used for food-grade liquid soaking. Background of the Invention

[0002] The most classic method of wine aging is in oak barrels. These pre-flavored barrels can be used for aging liqueurs; however, this aging process has some drawbacks, such as the long time required and high fixed asset costs. These barrels that have held wine are called wine flavoring barrels. These wine flavoring barrels have been steeped in the wine they contained.

[0003] These wine-flavoring barrels are extremely useful in the aging of liqueurs; they act as carriers for the transfer of certain compounds between wine and liqueur, contributing phenolic compounds from both grapes and wood to the liqueur. These compounds are highly beneficial, influencing the color, aroma, body, and mouthfeel of beverages aged in such wood, and are key to determining many of the final sensory characteristics of the liqueur. Oak barrels are designed to hold wine or spirits and prevent leakage, with their planks cut along the grain of the wood (i.e., the wood's ducts are parallel to the cut surface). Even so, due to their porosity, some degree of evaporation is unavoidable. After six months of flavoring, the thickness of the slabs soaked in the glaze is typically no more than 1 to 2 millimeters, while the slabs themselves are 25 to 30 millimeters thick.

[0004] Liqueurs aged in these barrels become more complex due to the abundance of numerous compounds, most of which are phenols. The evaporation of some distillate due to capillary action also affects the spirit, making it more refined and losing the harshness of the original distillate.

[0005] Because this aging technique is so beneficial, there is a need to accelerate the process. Accelerated aging refers to any technique that utilizes physical or chemical processes to age alcoholic beverages, thereby significantly shortening the product's production time. The main advantage of accelerated aging is reduced costs at this stage.

[0006] The immersion process involves soaking wood in a specific liquid, after which the wood will be used to age liqueurs. Techniques used to accelerate immersion include microwaves and ultrasound.

[0007] US Patent No. 2012 / 0164300A1 describes a method for aging an alcoholic beverage, the method comprising contacting the alcoholic beverage with fine wood powder with a particle size of less than 1 mm for a sufficient duration to transfer desired flavor and aroma into the alcoholic beverage.

[0008] Patent application number US2021 / 0017479 describes a method for producing aged liqueur, which includes placing a piece of wood into a liqueur bottle.

[0009] Therefore, it is highly meaningful to continue developing technologies to accelerate the originally slow wood impregnation process, optimize key variables such as pressure and exposure time to reduce the degradation of target phenolic compounds and shorten impregnation time, so that these woods can then be used for impregnation in other food-grade liquids (such as aging liqueurs). Summary of the Invention

[0010] The problems solved by this invention are, on the one hand, to accelerate the wood impregnation process, and on the other hand, to obtain wood in which the liquid impregnation volume accounts for a large proportion of the total wood volume, because, as shown in the prior art, the liquid penetration depth in modern wood is usually no more than a few millimeters.

[0011] This invention improves the impregnation of wood, allowing liquids to penetrate and circulate within the wood.

[0012] The density of these woods ranges from 0.55 g / cm³ to 0.75 g / cm³. This density is the original density of the wood prior to the treatment processes defined in this specification.

[0013] In the wood chips of the present invention, the amount of liquid impregnation accounts for 10% to 50% of the total volume of the wood chips, or the amount of dry residue impregnation accounts for 10% to 50% of the total weight of the wood block.

[0014] In this invention, impregnation refers to both transverse and axial impregnation, wherein transverse impregnation is perpendicular to the wood vessels, while axial or longitudinal impregnation is along the direction of the wood vessels.

[0015] The impregnated wood block has a thickness of at least 5 mm in one dimension.

[0016] The liquid or dry residue that has penetrated into the wood is a food-grade liquid or a dry residue of such a food-grade liquid.

[0017] The first aspect of the invention relates to a wood chip having a thickness of at least 5 mm in one dimension, impregnated with a food-grade liquid or a dry residue of a food-grade liquid, wherein the wood is selected from wood with a density ranging from 0.55 g / cm³ to 0.75 g / cm³, and the liquid is impregnated in the wood chip at a volume range of 10% to 50% relative to the total volume of the wood chip, or the dry residue is impregnated in the wood chip at a weight range of 10% to 50% relative to the total weight of the wood chip.

[0018] The main novelty of this invention lies in the ability to impregnate wood blocks with liquid or its dry residue, and these wood chips can then be used for impregnation with food-grade liquid.

[0019] Therefore, the use of the wood chips of this invention for macerating and aging food-grade liquids is also an aspect of this invention. Maceration and aging is a process of contacting liqueurs with wood for a specific period of time. The purpose of maceration and aging is to remove the harshness of the original spirit while adding the unique flavor characteristics of the wood. Maceration and aging in wood produces significant changes to food-grade liquids, especially liqueurs: reduced alcohol content, increased dry extract, a change in appearance from colorless to a straw-yellow hue, and enhanced aroma and complexity.

[0020] The wood chips of this invention are sized to hold containers, such as bottles, of food-grade liquids to be impregnated and aged with wood. The end consumer can then perform the impregnation of the food-grade liquid. Different wood chips of this invention can be used over time or in combination until the end consumer or manufacturer achieves the desired impregnation effect. Therefore, another aspect of this invention is a food-grade liquid bottle comprising the wood chips of this invention.

[0021] Another aspect of the invention is a barrel comprising a piece of wood of the invention inserted into a region that comes into contact with a liquid. Inserting the wood of the invention into the barrel can add value and flavor profile to the liquid contained within.

[0022] Also an aspect of the invention is a barrel containing the wood of the invention.

[0023] The process of this invention involves forcibly impregnating wood chips through a sequential system of varying pressures at different steps, thereby shortening the time required for the desired liquid to impregnate and remain within the wood.

[0024] Therefore, another aspect of the present invention relates to a method for impregnating wood chips with a food-grade liquid, characterized by comprising the following steps: a) Vacuum treatment step: In a sealed container, the wood chips are treated under a pressure range of 0.01 atm to 0.1 atm; b) Impregnation step: After step a), inject food-grade liquid into a sealed container to achieve a pressure within the sealed container ranging from 1 atm to 20 atm; and c) Excess liquid removal step: After step b), excess food-grade liquid is extracted from the wood chips in a sealed container under a pressure of 0.05 atm to 0.1 atm. Attached Figure Description

[0025] Figure 1 The left side shows three unimpregnated samples, and the right side shows three American oak samples impregnated according to the present invention, the wood being lightly baked and transversely cut at a 90-degree angle relative to the wood vessels; Figure 2The left side shows three unimpregnated samples, and the right side shows three American oak samples impregnated according to the present invention, which were pretreated by heavy baking and transversely cut at a 90-degree angle relative to the wood vessels; Figure 3 The left side shows three unimpregnated samples, and the right side shows three natural American oak samples impregnated according to the present invention, cut at a 45-degree angle to the direction of the wood vessels; and Figure 4 The right side shows three unimpregnated samples, while the left side shows three American oak samples impregnated according to the present invention, cut along the grain of the wood ducts without baking. Detailed Implementation

[0026] As previously stated, a first aspect of the present invention relates to a wood chip having a thickness of at least 5 mm in one dimension, impregnated with a food-grade liquid or a dry residue of a food-grade liquid, wherein the wood chip is selected from wood with a density ranging from 0.55 g / cm³ to 0.75 g / cm³, and the amount of liquid impregnated in the wood chip is 10% to 50% of the total volume of the wood chip, or the amount of dry residue impregnated in the wood chip is 10% to 50% of the total weight of the wood chip.

[0027] Preferably, the amount of the liquid or the dry residue of the liquid impregnated in the wood chips is 20% to 40% (volume ratio) of the total volume of the wood chips. More preferably, it is in the range of 25% to 35%.

[0028] Preferably, the wood is selected from: American cherry wood, European cherry wood, acacia wood, American maple, European maple, chestnut wood, American oak, and European oak.

[0029] Preferably, the wood chips are selected from: barrel lids, barrels, barrel boards, mixed barrel boards (i.e., barrel boards composed of multiple types of wood), barrel boards cut with the grain, barrel boards cut with the grain, barrel boards cut at an angle of 90° to 0° to the wood grain, baked barrel boards, cut and baked barrel boards, or impregnated wood inside barrel containers.

[0030] Preferably, the food-grade liquid is selected from: wine; liqueur; infusions of spices, herbs, fruits, flowers, and roots; fruit juice; coffee; cocoa; and liquid smokers. Preferably, the liquid smoker is obtained by burning peat or wood and condensing the resulting smoke.

[0031] As previously mentioned, another aspect is the use of the wood chips for impregnating food-grade liquids: preferably, for impregnating liqueurs or wines. Preferably, the liqueurs or wines are selected from: whiskey, vodka, gin, Armagnac, Cognac, coffee liqueurs, blackcurrant liqueurs, and vermouth.

[0032] Another aspect of the invention is a food-grade liquid bottle comprising the wood chips of the invention and a food-grade liquid. Preferably, the wood chips are in partial contact with the food-grade liquid. If the wood chips are only partially submerged in the food-grade liquid, with a portion exposed above the liquid surface, the capillary effect is enhanced; part of the wood chips is in contact with the food-grade liquid, and another part is in contact with the air inside the bottle. Preferably, the food-grade liquid is a liqueur or wine.

[0033] The final aspect of the invention relates to a method for impregnating wood chips with a food-grade liquid, characterized by comprising the following steps: a) Vacuum treatment step: In a sealed container, the wood chips are treated under a pressure range of 0.01 atm to 0.1 atm; b) Impregnation step: After step a), inject food-grade liquid into a sealed container to achieve a pressure within the sealed container ranging from 1 atm to 20 atm; and c) Excess liquid removal step: After step b), excess food-grade liquid is extracted from the wood chips in a sealed container under a pressure of 0.05 atm to 0.1 atm.

[0034] Preferably, steps a) to c) are repeated in a cycle to achieve a higher concentration of food-grade liquid in the wood chips, thereby adjusting the properties of the wood chips according to the desired sensory characteristics.

[0035] Preferably, the process includes a drying step performed outside the sealed container. Preferably, the drying is carried out until the relative humidity is below 10%.

[0036] Preferably, the execution time of step a) is 2 minutes to 300 minutes. Preferably, the execution time of step b) is 2 minutes to 420 minutes. Preferably, the execution time of step c) is 2 minutes to 60 minutes.

[0037] Preferably, step a) is performed in a sealed container at a pressure range of 0.01 atm to 0.05 atm for a duration of 2 minutes to 180 minutes; step b) is performed in a sealed container at a pressure range of 2 atm to 15 atm for a duration of 3 minutes to 360 minutes; and step c) is performed in a pressure range of 0.05 atm to 0.4 atm for a duration of 10 minutes to 30 minutes.

[0038] Preferably, step b) is performed under a pressure of 1 atm to 3 atm.

[0039] In one specific embodiment of the method of the present invention, the wood chip itself is also a sealed container, and the wood chip is specifically embodied in a barrel. Here, a barrel refers to a wooden container used for brewing and storing wine or liqueur. Therefore, in one specific embodiment, the impregnation method refers to a method of impregnating a barrel with a food-grade liquid, characterized by including the following steps: a) Vacuum treatment step: Treat the container under a pressure range of 0.01 atm to 0.1 atm; b) Impregnation step: After step a), inject food-grade liquid into the barrel, with the pressure controlled in the range of 1 atm to 3 atm; c) Excess liquid removal step: After step b), the excess food-grade liquid is extracted from the tank under a pressure of 0.05 atm to 0.1 atm.

[0040] In a preferred embodiment, the method further includes a step of toasting the wood prior to step a). More specifically, this involves toasting and / or burning. During this step, aromatic substances complementary to the wood's aroma are produced, and the carbonized wood acts similarly to activated charcoal for wines or liqueurs. Subsequent toasting alters the wood's structure and chemical composition, thereby increasing the quantity and complexity of volatile compounds not present in dry wood. Preferably, this step involves applying a heat source to the wood at a temperature of 130-230°C for 30-45 minutes, depending on the desired degree of toasting. As a result, the polymers constituting the wood (lignin, cellulose, hemicellulose, and tannins) undergo thermal degradation, generating small molecules or monomers with high aromatic intensity, which impart the properties of the final product. Based on temperature and toasting time, wood can be classified into different toasting grades. Toasting can be categorized into three types based on the time and temperature of the wood surface. An example of light baking is baking at 120°C to 130°C for 30 minutes, medium baking can be baking at 160°C to 190°C for 30 to 40 minutes, and an example of heavy baking is baking at 200°C to 210°C for 45 minutes.

[0041] Baking is applied to unimpregnated wood because it is a step before impregnation.

[0042] In another embodiment, the method includes a step prior to step a) of making at least one cut in the wood at an angle between 90° and 0° relative to the wood vessels, particularly 45°.

[0043] Numerous combination possibilities are unlocked: barrels with different slats, different wines, different treatments, slats with wood inlays cut at different angles, etc. The process of this invention allows for the combination of different toasting levels, impregnation liquids, and cutting angles, thereby customizing the characteristics and value that will give the final product. Example

[0044] Table 1 lists embodiments of the present invention, in which American oak chips are treated by the method of the present invention. The first step is carried out at 0.02 atm for 180 minutes, the second step at 12 atm for 360 minutes, and the third step at 0.1 atm for 30 minutes. The food-grade liquid used is wine. The table indicates the pretreatment and drying stages.

[0045] Table 1. Experimental Data

Claims

1. A wood chip, having a thickness of at least 5 mm in one dimension, impregnated with a food-grade liquid or a dried residue of the food-grade liquid, characterized in that, The wood chips are selected from wood with a density range of 0.55 g / cm³ to 0.75 g / cm³, and the amount of liquid impregnating the wood chips accounts for 10% to 50% of the total volume of the wood chips, or the amount of dry residue impregnating the wood chips accounts for 10% to 50% of the total weight of the wood chips.

2. The wood chips according to claim 1, characterized in that, The amount of liquid impregnated in the wood chips is 25% to 40% of the total volume of the wood chips, or the amount of the dry residue of the liquid impregnated in the wood chips is 25% to 40% of the total weight of the wood chips.

3. The wood chips according to any one of claims 1 to 2, characterized in that, The wood is selected from: American cherry, European cherry, acacia, American maple, European maple, chestnut, American oak, and European oak.

4. The wood chips according to any one of claims 1 to 3, characterized in that, The wood chips are selected from: barrel lids, barrel bodies, barrel boards, mixed barrel boards, barrel boards cut with the grain, barrel boards cut with the grain, barrel boards cut at an angle of 90° to 0° to the wood grain, baked barrel boards, cut and baked barrel boards, and impregnated wood inside barrel containers.

5. The wood chips according to any one of claims 1 to 4, characterized in that, The food-grade liquid is selected from: wine; liqueur; infusions of spices, herbs, fruits, flowers and roots; fruit juice; coffee; cocoa and liquid smokers.

6. Use of wood chips according to any one of claims 1 to 5 for impregnation with food-grade liquids.

7. The use according to claim 6, characterized in that, The food-grade liquid is selected from liqueurs or wines.

8. A liqueur bottle, characterized in that, It comprises wood chips as described in any one of claims 1 to 5 and a food-grade liquid to be impregnated.

9. A bucket, characterized in that, It comprises wood chips according to any one of claims 1 to 5.

10. A method for impregnating wood chips as described in any one of claims 1 to 5 with a food-grade liquid, characterized in that... Includes the following steps: a) Vacuum treatment step: In a sealed container, the wood chips are treated under a pressure range of 0.01 atm to 0.1 atm; b) Impregnation step: After step a), inject food-grade liquid into the sealed container to bring the pressure inside the sealed container to the range of 1 atm to 20 atm; as well as c) Excess liquid removal step: After step b), excess food-grade liquid is extracted from the wood chips in a sealed container at a pressure of 0.05 atm to 0.1 atm, and optionally a drying stage is carried out outside the sealed container.

11. The method according to claim 10, characterized in that, Step a) is performed in a sealed container at a pressure range of 0.01 atm to 0.05 atm for a duration of 2 minutes to 180 minutes; Step b) is performed in a sealed container at a pressure range of 2 atm to 15 atm for a duration of 3 minutes to 360 minutes; Step c) is performed in a pressure range of 0.05 atm to 0.4 atm for a duration of 10 minutes to 30 minutes.

12. The method according to any one of claims 10 to 11, characterized in that, This includes the wood baking step performed prior to step a).

13. The method according to any one of claims 10 to 12, characterized in that, It includes the step of making at least one cut along the wood at an angle to the wood ducts, which is performed before step a).

14. The method according to any one of claims 10 to 13, characterized in that, The pressure range in step b) is 1 to 3 atm.

15. The method of claim 14, wherein the wood chips are a sealed container and are a barrel.

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