"Food product obtained from the processing of beer waste"

DESCRIPTION

Technical field of the invention

The present invention is applicable in the food sector and, in particular, concerns a food product with a high fiber content and a procedure for the production thereof from beer production waste .

State of the art

The procedure for brewing beer consists mainly of the following steps: milling, mashing, filtering, boiling and hopping and, finally, cooling and oxygenation.

In a first step, the kernels of barley malt and any other cereals used are ground so as to make the starch contained therein available. The ground cereal is then mixed with hot water to allow the activation of the enzymes contained in the malt during the step defined as mashing. In effect, in the malt there are different enzymes, each with different actions, which operate optimally at different temperatures and pHs . The most important ones in the brewing sector are the diastase enzymes that break the cereal starches down into sugars. Once the starch has been transformed into sugars, the mixture obtained is filtered to separate the sugary wort from the so-called grains, i.e. the residue of the mash consisting of malt husks and other parts of the cereal in which no saccharification takes place. For a more effective action, the first wort (cloudier) is usually subjected to further filtrations that allow the sugars left imprisoned in the grains after the first filtration to be recovered. Filtering operations, even if very simple, are of fundamental importance in the production process of beer, in effect they are essential to avoid passing the grains into the wort and thus into the next steps of boiling where they would cause a release of tannins and other bitter substances in the finished beer, creating a product with an undesirable astringent taste.

Finally, the wort is boiled, the hops are added, and the wort is transferred to the fermenters, cooled through a heat exchanger to a temperature suitable for the type of fermentation chosen (high 18-25°C or low 7-15°C) and adequately oxygenated. The wort is now considered ready for the addition of yeast and for the fermentation step. One of the main challenges of the brewing sector, in this sense, is the need to dispose of the waste from the production of beer, represented by grains, spent yeasts and process water, which together account for about 90% of the raw materials used.

Ideally, this waste would be recovered, reused and, preferably, enhanced in value.

In particular, barley grains (on average about 20 kilos per 100 liters of beer) are characterized by a water content between 70-80%, which, together with the high content of organic matter, makes them particularly unstable as they are easily subject to putrefaction .

Today, the grains are transformed into livestock feed, which, however, has the disadvantage of requiring the transport of the grains promptly to the livestock farm because of their tendency to rot, which makes it impossible to store them.

Alternatively, the grains may be subjected to pyrogasification to convert them into charcoal and pellets.

Pyrogasification, however, is not without its drawbacks and does not completely solve the problem of disposing of the grains.

Summary of the invention

The authors of the present invention have surprisingly found that it is possible to enhance the waste obtained from the process of preparing beer to obtain a food product with a high fiber content .

Object of the invention

According to a first object, the invention describes a process for the preparation of a food product obtained from the waste of the beer production process.

In a preferred aspect, this food product is represented by a flour .

A second object food there are described products obtained from the flour of the invention.

Detailed description of the invention

According to a first object, a process for the preparation of a food product obtained from the waste of the beer production process is described.

For the purposes of the present patent application, the "waste" obtained from the beer preparation process, which is the input product in the process of the invention, is represented by the grains, i.e. the residue obtained from mashing; this residue consists in particular of malt husks and other parts of the cereal for which no saccharification (or hydrolysis of the saccharide portion) takes place.

In one aspect of the invention, the cereal is represented by barley .

According to alternative aspects, the cereal may be represented by oats, rye, rice, wheat.

In particular, the process of the present invention for the preparation of a food product from the waste of the beer production process comprises the steps of:

1) subjecting said waste to a heating step,

2) subjecting the product obtained from step 1 to grinding.

With respect to the waste of the beer production process, the grains are in the form of a wet mass with a water content varying from 50% to 90% by weight, depending on the characteristics of the beer production process from which they derive.

In a preferred aspect of the present invention, step 1) has to be conducted in such a way as to obtain a dry mass of grains with a water content of less than 15% by weight, preferably less than 8% by weight, and even more preferably about 6% by weight.

Advantageously, the achievement of these preferred values of the water content in the dry mass of grains allows the next step of grinding to be sped up.

According to one aspect of the invention, step 1) is preferably carried out within a maximum of 48 hours from the recovery of the wet mass of grains from the beer production process, thus limiting the processes of unwanted bacterial proliferation that may produce any unpleasant aromas in the final food product.

According to a preferred aspect of the invention, before step 1), a step of pressing of the grains may be carried out.

Advantageously, this pressing step allows for the removal of part of the water content present in the wet mass of the grains, thus speeding up the subsequent drying step.

In a preferred aspect of the invention, the pressing step allows at least 10%-80% of the water (weight/weight ) to be removed from the grains, preferably about 20-70%, and even more preferably about 20-80% (weight/weight ) .

When the pressing is carried out, preferably it should be carried out within 48 hours of the recovery of the wet mass of grains from the beer production process.

With regard to step 1) of the process, this comprises a drying step .

In particular, the drying step is preferably carried out in an oven.

Particularly preferred are ventilated ovens.

According to alternative aspects of the invention, the drying step may be carried out in different equipment, provided that the equipment is suitable for drying a wet mass of grains, such as a static oven or a dryer. In a preferred aspect of the present invention, the drying step is carried out at a temperature between about 60°C and 180°C, preferably at a temperature between about 70°C and 140°C and even more preferably at a temperature of about 100°C.

In a preferred aspect, the drying step is carried out for a period of time of more than 35 minutes, more preferably for a period of time between about 50 minutes and 9 hours and, even more preferably, for about 6 hours.

In a particular aspect of the invention, the drying step is conducted for a period of about 6 hours, where it is not preceded by a pressing step and the drying itself is conducted without the use of perforated trays on which to place the product in the oven.

The use of perforated trays may reduce the duration of the drying step.

When the pressing step is carried out and perforated trays are used, the drying step may last about 1.5-4 hours.

In accordance with a particular aspect of the invention, a sterilization step (pasteurization) is conducted before the drying step .

This pasteurization step is preferably carried out at a temperature of about 110°C-135°C, preferably about 130°C for a period of time of about 45-70 minutes, even more preferably between 55 and 65 minutes or about 60 minutes.

Particularly preferred, therefore, is a pasteurization step conducted at a temperature of about 130-135°C for a duration of about 1 hour . Advantageously, this combination does not adversely affect the organoleptic characteristics of the final product obtained by the present invention.

In addition, the final product is found to have a low, if not minimal, microorganism count (as determined by the ISO 48-33- 1:2013 method) .

Still advantageously, the completion of the sterilization step allows a hygienically safe, food-grade final product to be obtained. In particular, the sterilization step allows a dry mass of grains to be obtained with the following microbial load values: Escherichia coli <10 cfu/g, molds <1000 cfu/g, yeasts <1000 cfu/g and absence of Salmonella spp . in 25 g of product.

Depending on the preferred embodiment, the sterilization step is performed prior to the drying step; however, it is not excluded that, according to an alternative aspect, the drying step is performed prior to the sterilization step.

Moreover, the pasteurization and drying step may or may not be carried out in the same equipment.

For the purposes of the present invention, step 1) leads to a product characterized by a moisture content of less than about 10%, preferably less than about 5% and even more preferably less than about 2-4% (ISTISAN 1996/34 Met B Page 7) .

With regard to step 2) of grinding, this is carried out on the dry mass of grains deriving from step 1) of drying by means of manual or automatic cutting groups; examples not to be considered restrictive of such cutting groups comprise cutter grinders, blade granulators and blenders.

The dry mass of grains is preferably ground to an average particle size of between 0.1 and 0.8 mm, preferably about 0.2 and 0.4 mm.

Optionally, after the grinding step there is a sieving step of the dry mass of ground grains, which is carried out with a device with a mesh opening of about 0.2 and 0.8 mm.

Advantageously, the sieving step allows a dry mass of ground grains of substantially consistent grain size to be obtained and, again, any particles larger than 0.8 mm that are undesirable in the final product to be removed.

According to the present invention, the described process allows a gluten-free product to be obtained.

In particular, the flour obtained is characterized in that it includes gluten in a quantity of about 200 mg/kg, preferably less than 100 mg/kg, more preferably less than 50 mg/kg, even more preferably less than 20 mg/kg (ELISA methodology, AOAC 2014.03) .

In a much more preferable aspect, gluten is present in a quantity of less than 5 mg/kg (ELISA methodology, AOAC 2014.03) .

In one aspect of the invention, the processing of the grains allows the amount of gluten to be reduced by about 80%, and preferably by about 90%, with respect to the initial gluten content of the grains. In accordance with a preferred aspect, the process of preparing the flour of the present invention comprises a step of removing the gluten.

In particular, this removal is conducted with the aim of further reducing the gluten content in the final product represented by the flour obtained through the process of the invention .

In particular, this removal is achieved by an enzymatic treatment .

More specifically, this enzymatic treatment may comprise the use of a lactobacilli preparation and possibly also proteolytic fungal enzymes.

Lactobacillus may for example be represented by Lactobacillus sanfranciscensis and Lactobacillus plantarum.

Proteolytic fungal enzymes may for example be represented by proteases of Aspergillus oryzae, Aspergillus niger or mixtures thereof .

An example of a procedure that may be carried out is that reported in the Italian patent no. 1,392,414 and in the European patent application no. EP 2,890,817 (Giuliani S.p.A., Italy) .

According to another aspect of the invention, as an alternative or in addition to the aforesaid treatment, a treatment step of the grains may be conducted at the beginning of the process, with the aim of reducing the initial gluten content of the grains . According to a second object of the invention, a food product obtained from the grains coming from the waste of the beer production process is described.

In a particular aspect of the invention, the food product is obtainable by means of the process described above.

It has been surprisingly found that the product, the flour of the invention, comprises dietary fiber in a concentration of about 20%-55% by weight of the total weight of the food product.

Even more advantageously, the food product of the invention comprises dietary fiber in a concentration ranging from 35% to 50% by weight, preferably from 40% to 45% by weight of the total weight of the food product.

The value of the concentration of dietary fiber in the food product of the invention was measured by the method reported in AOAC Official Method 991.43 of 1994 and subsequent MP 2135 rev. 3 of 2015.

Surprisingly, the food product of the invention contains more dietary fiber than known food products derived from the milling of cereals in general.

In particular, referring to the food composition tables currently published by the Food and Nutrition Research Center of the Council for Agricultural Research and Analysis of Agricultural Economics, it may be seen that the food product of the invention comprises, by weight, a greater quantity of dietary fiber than the quantity of dietary fiber present in oatmeal, type 00 wheat flour, type 0 wheat flour, whole wheat flour and many others. Advantageously, the food product of the invention has the typically advantageous properties of a high fiber food such as improving intestinal function, stimulating colon motility, increasing the sense of satiety, reducing the glycemic index of carbohydrates .

In addition to the particularly advantageous concentration of dietary fibers, the product of the invention comprises protein in a concentration that varies from 10% to 30% by weight, preferably from 12% to 20% by weight of the total weight of the food product. The protein concentration was evaluated according to the 1992 AOAC Official Method 992.23.

According to a preferred aspect of the invention, the product is in the form of flour.

Advantageously, the flour of the invention may be stored for a long time, in warehouses or similar, avoiding problems due to degradation .

Still advantageously, the aforesaid flour is easy to handle and may therefore be handled and packaged according to methods and techniques known per se.

Still advantageously, the flour of the invention is particularly suitable to be used for the production of flour products and food items.

Preferably, such food items comprising the food product of the invention, are, by way of example, in the form of sweet or savory baked goods, mixes for sweet and savory items, bread, pasta, pizza, brioche, focaccia, cake, biscuit or crackers. Other food preparations such as creams or sauces may be obtained by using the flour of the invention.

In particular, the flour of the invention may be used for the preparation of pizza.

More specifically, the product of the invention in the form of flour has been used for making pizza dough.

Advantageously, due to the surprisingly higher concentration of dietary fiber compared to known flours, the use of the flour of the invention for making food items results in food items with a high fiber content, particularly appreciated for the improvement of intestinal activity.

The invention and the advantages thereof are best illustrated by the following examples. The following examples describe the process and the food product of the invention only for illustrative and non-limiting purposes.

Example 1

Procedure for the production of a flour product

Approximately 2 kg of wet grains are subjected to a drying step in the oven at a temperature of 130°C for about 1 hour. Drying was continued at a temperature of about 100°C for 6-6.5 hours or 80°C for about 8 hours, until a dry mass was obtained. The final product was ground to obtain an average grain size of about 0.2 and 0.4 mm.

Example 2

Food product A sample of the flour of Example 1 was analyzed, and the results obtained are shown in Table 1.

The phrase g/lOOg corresponds to the grams of component per 100 g of food product. The phrase mg/kg corresponds to the milligrams of component in one kilogram of food product.

Table 1

The fraction of fatty acids is composed as in Table 2.

Table 2

Example 3

Gluten reduction

The flour according to Example 1 was subjected to the gluten content reduction treatment of the invention.

For this purpose, the flour is mixed with water and with a lactobacilli preparation according to the present invention and a preparation of proteolytic fungal enzymes. After this step, the resulting mixture is left to ferment so that the enzymes may act and break down the gluten.

Finally, the fermented mass is left to dry.

The quantity of gluten has been reduced by more than 90% compared to the initial quantity.

From the aforesaid description, the advantages of the present invention will be immediately evident to the person skilled in the art .

In particular, the invention allows the recovery and enhancement of waste from beer production, otherwise intended for processes of low value, such as gasification for energy production.

Moreover, it fits very well into a more general context of environmental sustainability of the beer production chain.

The food product obtained may moreover be used for human consumption .

In this respect, it was noted that the flour described above has a high fiber content, which makes it desirable for health benefits . The described process implements methods that may be easily integrated vertically within the production of beer and is economically non-impacting.