DD267508A1 - PROCESS FOR THE EXCLUSION OF CEREALS UNDER PRESSURE-FREE CONDITIONS - Google Patents

Abstract

The invention relates to a non-pressurized starch digestion method which makes it possible to operate at temperatures by activating the self-enzyme potential of the cereal in the aqueous suspension (ratio cerium: water 1: 1 to 1: 3) using amylolytic, proteolytic and cellulolytic activities. when using Kühlwasserabgaengen require no further use of energy and achieve the same yields as in the conventional method.

Description

Field of application of the invention

The invention relates to a pressureless digestion and is in grain and grain distilleries (rye, wheat) applicable.

Characteristic of the known technical solutions

Pressureless digestion processes for the preparation of cereals into ethanol are becoming increasingly important internationally. They require much less energy than pressure.

The cold mash process, a form of non-pressurized digestion process, is known to operate at lower temperature than other processes. The steepness of the cereal is carried out at 45 to 50 ° C. In the temperature range from 58 ⁰ C to a maximum of 85 ⁰ C different restraints are maintained and starch hydrolyzing enzymes added, the saccharifying enzyme is generally dosed at temperatures <6O ⁰ C after re-cooling. Such a procedure is also followed by so-called "overnight mashes", which are subject to enzyme enrichment during the single-stage phase, but are not processed in the sense of the solution according to the invention.

When applying the known process steps not .1er desired grain digestion was achieved because the quality of the raw material is subject to considerable fluctuations, which may be due to sorting, cultivation and processing. It has therefore been attempted to overcome the disadvantages by improved milling of the crop and modification of the technology.

Furthermore, the dosed activities of microbial alpha-amylase had to be increased as opposed to the high pressure steaming method.

With the increasing use of miWobieller enzyme preparations also Machteile have set. Thus, serine-type microbial proteases, such as those present in many alpha-amylase preparations of commerce as alkaline protease, are partially completely inhibited by inhibitors of the cereal, above all wheat, rye, barley, and oat. From a biological biochemical point of view, such reactions of the inhibitors are likely to be defense reactions of the plant to microbial attack. If, nevertheless, an enzymatic effect is to be achieved, one must specify activities which are higher than the existing inhibitor concentrations.

Also, alpha-amylases of animal origin, e.g. Salivary and pancreatic amylase as well as those of cereal pests (grain beetle, cereal bug), strongly inhibited.

In contrast, bacterial or fungal alpha-amylases are scarcely inhibited by native alpha-amylase inhibitors. In practice, it can therefore be assumed, when using bacterial alpha-amylase preparations, that the alpha-amylase remains largely effective.

However, proteolytic side activities may be partially or completely inhibited depending on their composition. According to the current state of knowledge, the cereal inhibitors are temperature-stable and pH-stable. They are turned off only after exposure to temperatures above 8O ⁰ C and correspondingly long exposure time, which is the case with the high-pressure damping method.

The method described in DE-OS 3149931 is based on certain relatively high mash concentrations (ratio of water to grain 1: 1.8 to 1: 3.4) and operates in the temperature range below the viscosity increase of the starch.

-2- 26T508

As tracing agent Japanese commercial preparations, preferably from Rhizopus, but also malt are used. The

oingss' / Uten relatively high activities (cereals from 15.6 to 25 units per g of raw material) are together with the

Hefek'jltur added and fermented for 120h. WP 2 * 0137 describes a process that takes into account the quality of the raw materials and selected on the basis Cereal parameters, e.g. Case number and catalase activity, an adjusted digestion temperature and saccharification agent

allows.

The WP 220137 according to exploit the enzymatic potencies of the raw grain to use more, as they are by the plant's own Inhibitors can not be affected and grains own amylases naturally in terms of their specificity

most adapted to the substrate.

ZIe! the invention

The aim of the invention is to realize process parameters which ensure the full utilization of natural enzymes whose action is supplemented by the addition of enzyme preparations with amylolytic, cellulolytic and proteolytic activities 7U, so that it is possible to carry out starch solution and saccharification at temperatures When using well and cooling water outlets (3G3 to 323K), do not require any further use of heat energy.

Explanation of the essence of the invention

It has surprisingly been found that the alpha-amylase activity increases significantly in a Geireideschrot when stirring an aqueous suspension in the ratio 1: 1 to 1: 3 for 12 to 23 hours at temperatures of 283 to 303 K constantly or alternately. The increase in activity of alpha-amylase is 30 to 50% relative to the ursp. Only Activity dos Schrotes. In addition, further grain own I nzyme be activated because the increase in reducing sugar and the extract content in the meal suspension alone de r de ^r effect amylolytic activity can not be explained. These effects are further enhanced by the addition of proteolytic and cellulolytic activities. As a result of this complex action, it is possible to dispense with amylolytic enzymes which are customary in comparison to known pressureless digestion methods, since the activated corneigenic enzymes act more specifically than conventional amylolytic enzyme preparations.

For these effects to use rounder., Keeping temperatures below 50 ⁰ C is required. The addition of proteolytic and cellulolytic activities ensures that ethanol yields that are on the order of conventional methods can be achieved using the described procedure.

As a result of the solution according to the invention results in a method which does not require a separate heat energy supply by the use of the secondary energy accumulating in distillery {cooling water outlets) for the Maischprozbß.

Ausfuhrungsbeisplel

1100g Rogrjenfeinschrot be stirred in the mixing vessel with 220OmI to 298 K heated water and kept for 16 h with gentle stirring. Thereafter, it is heated to 313K, and 0, ^ 85g alpha-amylase (activity = 350 x 10 ⁹ ΙΕ / kg) and 2,42ml glucoamylase (activity - 3 x 10 ^e e / l) was added. After 1 h is cooled by addition of cold water to shutdown temperature. After usual fermentation with a distillery yeast within, on 70 h the mash arrives to the distillation. The yield is 621 U / 100kg starch.

Claims (6)

1. A process for the digestion of cereals, preferably rye, under unpressurised conditions using microwell enzyme preparations or enzyme culture solutions having amylolytic, proteolytic and cellulolytic activity, characterized in that, prior to the actual processing, thecarycidated enzymes are removed by treatment of the Activated cereals in suspension with water by a grain-water ratio of 1: 1 to 1: 3 is used. 2. The method according to item 1, characterized in that the adjusted to 283 to 303 K suspension during the treatment constantly or alternately stirred and the process is stopped after 12 to 20h. 3. The method according to item 1 and 2, characterized in that the grain suspension after 12 to 20 hours of alpha-amylase is supplied. 4. The method according to item 1 to 3, characterized in that the grain suspension during treatment celluiolytische and proteolytic activities are supplied, wherein the addition of these enzyme mixtures is proportional and stepwise. 5. The method according to item 1 to 4, characterized in that the pH of the mash is adjusted in a range of 4 to 6.0. 6. The method according to item 1 to 5, characterized in that the mash is heated by the addition of hot water from 313 to 333K to 293 to 313K.