Low Alcohol or Alcohol Free Fermented Malt Based Beverage and Method for Producing It

Abstract

The present invention concerns an alcohol free or low alcohol fermented malt based beverage having an alcohol content of not more than 0.7 vol. %, characterized by a relationship yA x.sup.b wherein A=0.25 and b=1.5, and wherein x is the ratio between unfermentable over real extracts, wherein the unfermentable extract is the value of the real extract less the total content of real sugars, which consist of fructose, maltose, glucose, maltotriose, and saccharose, and y is the ratio between the combined content of maltopentaose, maltohexaose, and maltoheptaose over the total amount of main sugars, wherein the main sugars consist of fructose, maltose, glucose, saccharose, maltotriose, maltotetraose, maltopentaose, maltohexaose, and maltoheptaose. It also concerns a method for producing an alcohol free or low alcohol fermented malt based beverage comprising Preparing a wort (23) of fermentability not higher that 29%, preferably, not higher than 25%, more preferably at most 20%; and Fermenting the thus prepared wort in a fermentation tank (4) by a cold contact process.

Claims

1. Alcohol free or low alcohol fermented malt based beverage having an alcohol content of not more than 0.7 vol. %, characterized by a relationship
yA x.sup.b wherein A=0.25 and b=1.5, and wherein x is the ratio between unfermentable over real extracts, wherein the unfermentable extract is the value of the real extract less the total content of real sugars, which consist of fructose, maltose, glucose, maltotriose, and saccharose, and y is the ratio between the combined content of maltopentaose, maltohexaose, and maltoheptaose over the total amount of main sugars, wherein the main sugars consist of fructose, maltose, glucose, saccharose, maltotriose, maltotetraose, maltopentaose, maltohexaose, and maltoheptaose.

2. Fermented malt based beverage according to claim 1, wherein b=1, and/or wherein preferably A=0.3, more preferably 0.35.

3. Fermented malt based beverage according to claim 1 or 2, wherein the ratio x between unfermentable over real extracts is of at least 25%, and/or the sugars ratio y is of at least 25%, preferably at least 30%, more preferably at least 35%

4. Fermented malt based beverage according to any of the preceding claims, wherein the alcohol content is not more than 0.5 vol. %, preferably not more than 0.3 vol. %, more preferably not more than 0.1 vol. %, most preferably, not more than 0.05 vol. %.

5. Fermented malt based beverage according to any of the preceding claims, wherein the unfermentable extract is at least 4.0 g/100 ml, preferably at least 5.5 g/100 ml, more preferably 6.0 g/100 ml, most preferably at least 6.5 g/100 ml.

6. Fermented malt based beverage according to any of the preceding claims, wherein the real extract is at least 5.0 g/100 ml, preferably at least 6.0 g/100 ml, more preferably at least 7 g/100 ml.

7. Fermented malt based beverage according to any of the preceding claims, wherein the total content of sweet sugars is not more than 3 g/100 ml, preferably not more than 2 g/100 ml, more preferably not more than 1.5 g/100 ml.

8. Fermented malt based beverage according to any of the preceding claims, wherein the beverage is a beer.

9. Method for producing an alcohol free or low alcohol fermented malt based beverage comprising the following steps: (a) Mashing grain grits by inactivating -amylase and reacting -amylase with starch within the grits to produce a wort of fermentability of not more than 29%, preferably not more than 25%, more preferably nor more than 20%; and (b) Fermenting the thus produced wort by a cold contact process to produce a beer having an alcohol content of not more than 0.7 vol. %, preferably not more than 0.5 vol. %, more preferably not more than 0.3 vol. %, most preferably not more than 0.03 vol. %.

10. Method according to claim 9, wherein the grain grits comprises malt, preferably admixed with corn grits and/or rice grits.

11. Method according to claim 9 or 10, wherein -amylase is inactivated by bringing the temperature of the grits mash over 75 C., preferably over 85 C. and wherein thermostable -amylase is added.

12. Method according to any of claims 10 and 11, wherein the grits comprises 30 to 100 wt % malt and 70 to 0 wt % corn grits, and wherein the mashing comprises the following steps: (a) If any, adding to a corn grits mash an appropriate amount of thermostable -amylase and heating the corn mash to a temperature of 85 to 100 C.; (b) Mashing in malt at a temperature of 70 to 100 C., preferably 78 to 85 C., and combining it with the corn mash, if any, and bringing the temperature of the thus obtained mash to higher than 75 C., preferably higher than 85 C. and adding thereto thermostable -amylase (c) Raising the temperature to a value of 90 to 98 C. and transferring the mash to lautering.

13. Method according to any of claims 9 to 12, wherein the wort is boiled and has then a gravity comprised between 6 and 20 P, preferably between 8 and 12 P, more preferably between 9 and 11 P.

14. Method according to any of claims 9 to 13, wherein the wort is then cooled to a temperature of 2 to 8 C., preferably of 2 to 5 C., and then cooled to 2 to 0 C. for the cold contact fermentation stage.

15. Method according to any of claims 9 to 14, wherein a beer according to any of claims 1 to 8 is produced.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0024] For a fuller understanding of the nature of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawings in which:

[0025] FIG. 1: shows a schematic representation of the main steps for the production of a fermented malt based beverage.

[0026] FIG. 2: shows an embodiment of temperature-time profile in the cereal cooker and the mash tun, according to the present invention.

[0027] FIG. 3: shows a plot of the ratio of x vs y for a number of beers according to the present invention compared with prior art commercial NA beers and showing the function, y=A x.sup.b, defining the subject matter of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0028] The fermented malt based beverage of the present invention has an alcohol content of not more than 0.7 vol. %, and may even have alcohol contents of not more than 0.1 vol. % or even 0.05 vol. % with a flavour profile which preferably remains very close to normal lager beer. The flavour profile of a beer is a very complex issue and is usually assessed by a panel of experts marking several dozens of parameters such as sweetness, fruitiness, bitterness, after-bitterness, caramel note, worty note, and the like. Although some flavour characteristics may be associated with a specific component, such as bitterness being associated with the presence of hops, the overall flavour profile is beyond a full understanding, as there are a myriad of parameters controlling it: types and contents of the components used, time-temperature profiles, pH, etc. Any change in one of said parameters, affects the flavour profile of a beer.

[0029] A typical brewing process involves the main steps schematically depicted in FIG. 1. Malt (21) is mashed in a mash tun (1) to transform starch into sugars. It is possible to add thereto grain grits (22) previously cooked in a cereal cooker (2). When mashing is over, mixture is transferred to lautering where the solid phase is separated from the liquid wort (23), the latter being loaded in a copper (3), sometimes also called kettle. The wort is boiled and hops is added, giving to beer its distinct bitter taste. During this stage, many reactions, such as Maillard reactions, occur, developing various flavours and aroma characteristic of each beer. At the end of the boil, the hopped wort is clarified and cooled down prior to transferring it into a fermentation tank (4) where the fermentable sugars, in presence of yeast (25), will be transformed into alcohol and CO.sub.2. After fermentation is completed, the liquid is conditioned for several days or even weeks in conditioning tanks (5) until the beer has matured and is ready to be bottled or transferred into kegs (6).

[0030] The malt based beverage of the present invention can be produced by a method as disclosed supra, further characterized in that it comprises: [0031] (a) Preparing a wort (23) of fermentability not higher than 29%, preferably not higher than 25%, more preferably at most 20%; and [0032] (b) Fermenting the thus prepared wort in a fermentation tank (4) by a cold contact process.

[0033] Such low fermentability wort (23) is prepared in a mash tun (1) by inactivating -amylase in a grain grits mash and reacting -amylase with starch within the grits. -amylase is best inactivated by heating the mash at a temperature higher than 75 C., preferably higher than 85 C. Because a substantial fraction of -amylase formed by malt may be inactivated too at a temperature higher than 75 C., it may be necessary to add thermostable -amylase to the mash, for instance Thermamyl of Novo Enzyme. The mash is maintained at such thermal conditions until a wort (23) of fermentability of at most 29%, preferably at most 25%, more preferably not higher than 20% is obtained, resulting in a wort which is rich in poorly fermentable dextrins, typically maltopentaose, maltohexaose, and maltoheptaose, and concomitantly which is poor in highly fermentable sweet sugars (i.e., glucose, fructose, maltose, saccharose, and maltotriose). These worts are richer in dextrins and poorer in sweet sugars than a wort of say 30% fermentability as disclosed in GB2181450. Beyond yielding a beer with less alcohol after the fermentation process, it is believed that the higher content in dextrins is responsible for less Maillard reactions during the boiling step in the copper (3). The Maillard reaction is [0034] a chemical reaction between an amino acid and a reducing sugar, usually requiring heat, [wherein] the reactive carbonyl group of the sugar reacts with the nucleophilic amino group of the amino acid, and forms a complex mixture of poorly characterized molecules responsible for a range of odors and flavo[u]rs [ . . . ]. In the process, hundreds of different flavor[u]r compounds are created. These compounds in turn break down to form yet more new flavor[u]r compounds, and so on. Each type of food has a very distinctive set of flavor[u]r compounds that are formed during the Maillard reaction (cf. http://en.wikipedia.org/wiki:Maillard_reaction).

[0035] Reducing Maillard reactions in the beer brewing process is not an objective per se, but it was observed that in the case of NA beers, it yields a flavour profile which is closer to normal lager beer. Without being bound by any theory, it is believed that a higher fraction of dextrin with respect to sweet sugars in the mash reduces the number of reactive carbonyl groups available for Maillard reactions during the boiling of the wort in the copper (3).

[0036] Preferably the grain grits comprises malt (21), such as malted barley, which Is preferably admixed with corn grits and/or rice grits (22). For example, the grits may comprise 30 to 100 wt % malt and 70 to 0 wt % corn grits and/or rice grits. The water to grist ratio in the mash is preferably comprised between 3 and 6, preferably between 4 and 5, mote preferably between 4 and 4.5, and the pH is maintained between 5 and 7, preferably between 5.2 and 6, more preferably between 5.4 and 5.6.

[0037] FIG. 2 shows an example of temperature-time profile during mashing. In the embodiment illustrated therein, malt (21) is admixed with grain grits (22), for example corn grits, which is first cooked in a cereal cooker (2) at a temperature between 85 and 100 C. Thermostable -amylase can be added to the cooking corn grits. Malt (21), e.g., barley malt, is mashed in a mash tun (1) at a temperature of 78 to 85 C. with additional thermostable -amylase. The corn grits Is added into the mash tun containing the malt and the temperature is raised to above 85 C. The necessary amount of thermostable -amylase may be added at any time during mashing. When mashing is completed, the temperature is raised again to 90-98 C. for the transfer to lautering to recover a wort of fermentability of at most 25%, preferably, at most 20%.

[0038] After boiling of the wort in the copper in presence of hops, the boiled wort preferably has a gravity comprised between 6 and 20 P, preferably between 8 and 12 P, more preferably between 9 and 11 P. The wort is then cooled to a temperature of 2 to 8 C., preferably of 2 to 5 C. before transferring it into a fermentation tank (4), wherein the wort is fermented by a cold contact process at a temperature of 0 to 2 C. for 12 to 72. It is possible to flush beer or malt based beverage shortly with CO.sub.2 before transferring it to conditioning tanks to yield a NA beer or malt based beverage of alcohol content of not more than 0.7 vol. %, down to even not more than 0.05 vol. %. Some dilution Is not excluded but only to fine tune the final alcohol content of the beer, and not as the main mean to reach a low alcohol content. Optionally sweet sugars or other additives can be added to the fermented malt based beverage in order to alter the flavor profile so as to obtain sweet beverages wherein the beer flavor is substantially masked.

[0039] Different batches of beer obtained by such process, all having an alcohol content of less than 0.45 vol. %, were tested by a panel of experts, and their conclusion was that their flavour profiles were particularly close to the ones of STELLA ARTOIS and JUPILER BLUE, two popular lager beers in Belgium. Table 1 lists the alcohol contents, extracts and sugars contents of a number of commercial NA beers (CEX1 to CEX16) compared with the ones of NA beers according to the present invention (EX1 to EX13). As many of the NA beers of the comparative examples belong to the competition, it is not always known how they were processed. It is known, however, that the NA beer of CEX3 was obtained by arresting fermentation by a cold contact process, whilst the NA beers of CEX14-16 were obtained by evaporation.

[0040] It can be seen from Table 1, that the sweet sugars contents (=fructose, glucose, maltose, saccharose, and maltotriose) of the NA beers according to the present invention are quite low when compared with CEX3 obtained by a cold contact fermentation process. This Is to be expected, since in these beers, the wort contains a high proportion of fermentable, sweet sugars, which are not allowed to ferment by the cold contact process, and thus remain in the beers, giving a strongly sweet taste. Based on their high contents of sweet sugars, it can be assumedwith no guaranteethat the NA beers of CEX4 and 9 were also fermented by cold contact. On the other hand, as could be expected, the content in sweet sugars of NA beers of CEX14-16 is very low, since the sweet sugars present in the wort were allowed to ferment, but the alcohol thus produced was withdrawn by evaporation. Based on their low amounts of sweet sugars, it can be assumed that the NA beers of CEX10&11 were obtained by retrieving the alcohol after fermentation, by any process such as evaporation, distillation, etc.

TABLE-US-00001 TABLE 1 alcohol content, extracts, and sugars content of a number of prior art and inventive NA Beers Unfermentable Sweet sugars Alcohol Real extract Real extract extract Fructose Glucose Maltose Saccharose Maltotriose Beer vol. % g/100 g g/100 ml g/100 ml g/100 ml g/100 ml g/100 ml g/100 ml g/100 ml CEX1 0.46 3.71 3.76 2.57 0.55 0.60 0.02 0.00 0.02 CEX2 0.42 4.28 4.34 2.44 0.83 1.01 0.02 0.00 0.04 CEX3 0.43 6.65 6.81 2.17 0.18 0.45 3.13 0.00 0.88 CEX4 0.04 6.61 6.77 2.42 0.49 0.67 2.09 0.64 0.46 CEX5 0.01 4.67 4.75 2.60 0.22 0.28 1.31 0.07 0.27 CEX6 0.57 5.28 5.38 2.81 0.11 0.18 1.62 0.00 0.66 CEX7 0.00 5.87 6.00 2.28 0.22 0.17 2.57 0.01 0.75 CEX8 0.48 7.12 7.31 3.73 0.06 0.77 2.41 0.00 0.34 CEX9 0.04 6.18 6.32 2.00 0.13 0.34 2.91 0.03 0.91 CEX10 0.33 4.47 4.54 4.09 0.00 0.00 0.07 0.00 0.38 CEX11 0.04 4.38 4.45 4.07 0.00 0.00 0.04 0.00 0.34 CEX12 0.22 3.64 3.69 1.29 0.14 0.29 1.58 0.00 0.39 CEX13 0.06 6.34 6.49 2.72 0.00 0.00 2.91 0.06 0.80 CEX14 0.40 3.66 3.71 3.10 0.39 0.22 0.00 0.00 0.00 CEX15 0.44 4.10 4.16 3.47 0.40 0.24 0.00 0.00 0.05 CEX16 0.45 5.34 5.44 4.99 0.29 0.14 0.00 0.00 0.02 EX1 0.01 7.78 8.01 6.58 0.31 0.27 0.38 0.00 0.47 EX2 0.31 7.47 7.68 6.55 0.16 0.12 0.38 0.00 0.47 EX3 0.00 7.94 8.18 5.88 0.28 0.61 0.83 0.03 0.55 EX4 0.00 8.02 8.26 6.47 0.35 0.45 0.48 0.00 0.51 EX5 0.12 7.77 8.00 6.02 0.31 0.44 0.73 0.00 0.50 EX6 0.14 7.71 7.93 6.50 0.31 0.27 0.38 0.00 0.47 EX7 0.13 7.78 8.01 5.98 0.31 0.45 0.75 0.00 0.52 EX8 0.13 7.80 8.03 6.01 0.31 0.46 0.74 0.00 0.51 EX9 0.35 6.42 6.57 5.20 0.12 0.10 0.57 0.00 0.58 EX10 0.45 7.21 7.40 5.83 0.12 0.08 0.70 0.00 0.67 EX11 0.47 7.21 7.40 5.80 0.12 0.08 0.73 0.00 0.67 EX12 0.36 7.42 7.62 6.19 0.13 0.10 0.58 0.00 0.62 EX13 0.43 7.30 7.50 5.92 0.13 0.11 0.67 0.00 0.67 FIG. 3 malto-5-6-7-ose Sweet sugars Unfermentable Maltotetraose Maltopentaose Maltohexaose Maltoheptaose total extract Beer g/100 ml g/100 ml g/100 ml g/100 ml g/100 ml % malto 5,6,7-ose % CEX1 0.27 0.06 0.04 0.02 1.19 68% 8% CEX2 0.18 0.05 0.03 0.01 1.90 56% 4% CEX3 0.15 0.02 0.03 0.01 4.64 32% 1% CEX4 0.14 0.02 0.02 0.01 4.35 36% 1% CEX5 0.04 0.01 0.02 0.01 2.15 55% 2% CEX6 0.09 0.13 0.04 0.04 2.57 52% 7% CEX7 0.16 0.02 0.02 0.01 3.72 38% 1% CEX8 0.34 0.08 0.07 0.04 3.58 51% 5% CEX9 0.09 0.02 0.03 0.02 4.32 32% 2% CEX10 0.29 0.03 0.05 0.03 0.45 90% 13% CEX11 0.27 0.03 0.05 0.02 0.38 91% 14% CEX12 0.04 0.01 0.01 0.01 2.40 35% 1% CEX13 0.23 0.03 0.03 0.02 3.77 42% 2% CEX14 0.37 0.05 0.04 0.01 0.61 84% 9% CEX15 0.27 0.05 0.10 0.03 0.69 83% 16% CEX16 0.46 0.08 0.11 0.03 0.45 92% 20% EX1 0.21 0.22 0.60 0.20 1.43 82% 41% EX2 0.21 0.22 0.60 0.20 1.13 85% 47% EX3 0.35 0.30 0.71 0.15 2.30 72% 32% EX4 0.22 0.23 0.62 0.20 1.79 78% 37% EX5 0.33 0.29 0.70 0.15 1.98 75% 35% EX6 0.21 0.22 0.60 0.20 1.43 82% 41% EX7 0.35 0.29 0.71 0.15 2.03 75% 34% EX8 0.34 0.30 0.72 0.15 2.02 75% 35% EX9 0.13 0.23 0.41 0.09 1.37 79% 34% EX10 0.33 0.44 0.73 0.00 1.57 79% 38% EX11 0.33 0.48 0.72 0.04 1.60 78% 40% EX12 0.30 0.27 0.65 0.14 1.43 81% 40% EX13 0.29 0.42 0.71 0.06 1.58 79% 40%

[0041] All the NA beers on the market have an unfermentable extract below 5.0 g/100 ml, which is lower than the one of the NA beers of the present invention. The unfermentable extract is defined as the value of the real extract less the total content of sweet sugars, which consist of fructose, maltose, glucose, maltotriose, and saccharose. Another observation is that the content of high molecular weight dextrin, viz., maltopentaose, maltohexaose, and maltopentahose is quite low in the NA beers on the market, compared with the NA beers according to the present invention; the combination of maltopentaose, maltohexaose, and maltopentahose is hereinafter referred to as malto-penta/hexa/hepta-ose. FIG. 3 plots the ratio of unfermentable to real extracts, hereinafter referred to as x, vs the ratio of the contents of malto-penta/hexa/hepta-ose to total sugars, hereinafter referred to as y. The total sugars consist of fructose, glucose, maltose, saccharose, maltotriose, maltotetraose, maltopentaose, maltohexaose, and maltopentahose. Relative values bounded between 0 and 1 were considered to account for possible dilutions of varying degrees between NA beers of different origins and obtained from different processes in the hope of yielding a relationship between these two parameters and thus of defining a master curve for NA beers. Indeed, it was observed that all the NA beers on the market (white circles) clearly followed a master curve of the type, y=A x.sup.b regardless of their origins (cf. thin dotted line in FIG. 3), whilst the NA beers according to the present invention (black circles) distinguished themselves clearly from this trend.

[0042] The fermented malt based beverages of the present invention therefore characterize themselves from the beers on the market in that

yA x.sup.b

wherein A=0.25 and b=1.5, as represented in FIG. 3 with a thick solid line. In a preferred embodiment, b=1, to yield a linear relationship represented in FIG. 1 with a thin dashed line. A may take any value between 0.25 and 0.45, such as 0.3 or 0.35, and the power b may take any value between 1 and 1.5, such as 1.25 or 1.35.

[0043] In a preferred embodiment, the fermented malt based beverage of the present invention is characterized by: [0044] a ratio x between unfermentable over real extracts of at least 25%, and/or [0045] a sugars ratio y of at least 25%, preferably at least 30%, more preferably at least 35%

[0046] As discussed above, the preparation of a won of fermentability not higher than 25% combined with a cold contact fermentation process allows a fermented malt based beverage and in particular NA beer to be produced having a flavour profile very close to normal lager beers and an alcohol content lower than 0.7 vol. %, such as not more than 0.5 vol. %, preferably not more than 0.3 vol. %, more preferably not more than 0.1 vol. %, and even not more than 0.05 vol. %. It is believed that such a close matching flavour profile of the NA beers of the present invention with normal lager beer is due inter alia to a high value of real extracts yielding body, in combination with a high amount of unfermentable extracts, and in particular of a high extract of unfermentable malto-penta/hexa/hepta-ose, resulting in a low amount of sweet sugars. In particular, a malt based beverage according to the present invention may have a real extract of at least 5.0 g/100 ml, preferably at least 6.0 g/100 ml, more preferably at least 7 g/100 ml and an unfermentable extract of at least 4.0 g/100 ml, preferably at least 5.5 g/100 ml, more preferably 6.0 g/100 ml, most preferably at least 6.5 g/100 ml. This should result in a total content of sweet sugars not exceeding 3 g/100 ml, preferably not more than 2 g/100 ml, more preferably not more than 1.5 g/100 ml.