AU717831B2 - Process for processing protein-containing plants - Google Patents

Abstract

The invention concerns a method of processing protein-containing plants, in particular lupins, by means of which method proteins and other substances having in particular a nutritional value are prepared such that the proteins can be used for producing foodstuffs and fodder without undesirable effects, as well as for other purposes, e.g. as raw materials used in technology. To this end, at least two extractions (8, 11) are carried out in a method according to the invention: in one extraction (8) antinutritive constituents (9) of the plants or plant components are separated and in the other extraction (11) proteins are extracted.

Description

"Process for processing protein-containing plants" The invention relates to a process for processing protein-containing plants in accordance with the generic part of claim 1.

Various plants, for example the various lupin species, are high in plant proteins of high nutritional value. Such proteins can be a valuable addition in the production of foodstuffs and animal feeds. Since most plants and, in particular, the abovementioned lupin species not only contain the desired proteins of high nutritional value, but also so-called antinutritive substances, e.g. alkaloids, certain sugars (oligosaccharides) and the like, some of which may even be poisonous, the plants or their seeds must be pretreated before the proteins are utilized.

The water treatment of lupin seeds to extract such antinutrivite substances, in particular lupin alkaloids, was already known to various ancient civilizations (Egyptians, Greeks, Incas and the like).

The processes for debittering lupin seeds were developed further in the past and improved using modern techniques. Thus, for example, EP 084 547 describes a process for debittering lupin seeds based on water as the extractant. However, the main objective of this publication is to obtain, from the lupin seeds, the alkaloids which can also be exploited as crop protection products or plant conditioners. The protein-containing filter cake obtained in accordance with this process is dried and recommended as a foodstuff and animal feed of high nutri- Stional value. This publication contains no instructions 2 for processing this filter cake further. Concentration is merely mentioned as a possibility, but no further details are provided.

Furthermore, a process for preparing a proteincontaining lupin milk is given in EP 449 396. This process essentially exploits the process which is well known from processing soya plants, but also lupins, in which soaked lupin seeds are ground, stirred with water and subsequently expressed (cf. in this context Richard Yu, Lupin Newsletter, February 1989, p. 33 et seq.). The resulting lupin milk is intended as a raw material for the preparation of foodstuffs.

However, the disadvantage of this process is that all water-soluble antinutritive substances remain in the lupin milk. If a bitter lupin is processed by this process, the resulting lupin milk is inedible since it is high in alkaloids, i.e. bitter substances.

This process is also disadvantageous when processing sweet lupins since in this case too the lupin milk contains antinutritive substances such as, for example, oligosaccharides, alkaloids and the like, which cause unpleasant side-effects in the human digestive tract, for example flatulence.

Moreover, there is no indication whatsoever in the prior art on the utilization of other valuable constituents of the protein-containing plants to be processed, which may be present, for example, in the form of fiber.

It is therefore an object of the invention to propose, starting from the abovementioned prior art, a process for processing protein-containing plants, in particular lupins, by means of which proteins and other nutritionally particularly valuable substances are prepared in such a way that they can be used for the production of foodstuffs and animal feeds, but also for other purposes, for example as industrial feedstocks, without undesirable side-effects.

SThis object is achieved by the characterizing features of claim 1.

3 Advantageous developments and embodiments of the invention are made possible by the measures given in the subclaims.

Accordingly, a process according to the invention involves at least two extractions being carried out, where antinutritive constituents, for example alkaloids, oligosaccharides and the like, of the plants or the plant organs are separated off in one extraction and proteins are extracted in the other extraction.

This process allows a protein-enriched fraction to be obtained which can be used readily in the food sector since antinutritive substances have been extracted. Depending on the original plant material, however, the antinutritive substance fraction may also be used further, for example as crop protection product, plant conditioner, in medicine and the like. Even the third fraction originating from the two extractions may contain valuable constituents, for example fiber, vitamins and the like, in the case of certain original plant materials, such as lupins or the like.

The plants and/or plant seeds are preferably comminuted prior to the extractions so as to increase the surface at which the extractant, or extractants, can attack. To increase the yield, it is recommended to comminute, for example grind, the plants and/or plant seeds to such an extent that the structure of a coarse flour is obtained. Good results were achieved with a coarse flour having particle sizes of between 200 and 600 micrometers.

Since the resulting crude product from the plants or their seeds contains, inter alia, also fats and corresponding enzymes for cleaving these fats, so-called lipoxygenases, it is recommended, prior to the first extraction, to subject this crude product to a treatment in which the abovementioned enzymes are inactivated. This prevents oxidation of the existing unsaturated fatty acids taking place in the crude product, or in the process products obtained by the process described, in the case of corresponding storage. Such an oxidation leads to 4 a rancid taste, which would adversely affect a use in the food sector. Also, the proposed treatment considerably reduces the introduction of microorganisms into the processing plant used.

Inactivation of such enzymes can be effected, for example, thermally by the action of heat. A combined action of heat and moisture improves enzyme inactivation.

Inactivation is therefore preferably carried out by blanching. This blanching process is preferably carried out using steam. However, brief immersion in hot water would also be conceivable, inter alia.

A further advantage of this steam treatment is that the air which is present in cavities, such as pores and the like, of the raw material is displaced by the steam. If this raw material is subsequently transferred into an environment of cold extractant, the steam located in these cavities condenses and the extractant is drawn into these cavities. In a manner of speaking, the raw material is thus impregnated with extractant. The result is therefore an improved wetting of the surface with the extractant, which increases the efficacy of the extraction. Preferably, these processes take place in a closed system, i.e. a sealed reaction vessel.

To improve the protein/fiber ratio even before carrying out the extractions according to the invention, it is recommended only to process the plant seeds.

Husking the seeds prior to comminution allows much of the fiber to be removed as early as at this point in time.

The husks themselves can be further processed as fiber, in particular in ground form, for example for use in the foodstuff or animal feed sector. However, an industrial use, for example as insulation material in the construction industry and the like, would also be conceivable.

The process according to the invention is particularly well suited to processing lupins. It has emerged that processing lupins or lupin seeds allows products to be obtained which have an almost neutral flavor and which are distinguished by being high in proteins of high I nutritional value and high-quality, i.e. fermentable, 5 fiber. The process is suitable for processing both bitter and sweet lupins since even the latter contain antinutritive substances, in particular in the form of the oligosaccharides which have already been mentioned, which are unsuitable for use in foodstuffs, as stated above. An advantage in processing bitter lupins is that the alkaloid-containing fraction resulting from one of the two extractions can also be further processed as crop protection products, plant conditioners, for medicinal purposes and the like, as has already been mentioned.

Since in particular water is outstandingly suitable as an extractant for use in the food sector, it is recommended to carry out at least one of the extractions according to the invention using water as the extractant. The yield of the relevant extraction can be optimized by modifying the pH.

A particular advantage is the finding that both extractions according to the invention can be carried out with water as the extractant. This procedure exploits the fact that most of the existing proteins which are in principle soluble in water do not dissolve when extracting in an acidic environment, which means that essentially only the antinutritive substances are extracted.

Both extractions are advantageously carried out under atmospheric pressure since this keeps the outlay when establishing and operating a suitable environment within limits. Moreover, at least one of the two extractions is carried out using cold water, i.e. in a temperature range of between 15 0 C and 25 0 C. This largely reduces microbiological activity, in particular undesirable multiplication of bacteria, in the course of the process.

Thus, it is possible to extract twice in succession with water as the extractant, the first extraction being carried out in an acidic environment and the second extraction in an alkaline environment. Preferably, the first extraction is carried out at a pH of from 3.5 to particularly good results having been achieved at between 4.5 and 5.0. It is recommended to carry out the S second extraction at a pH of greater than 7.5, preferably 6 greater than 8. By intentionally varying the pH of the first and/or the second extraction, it is possible to obtain a selective choice of specific proteins.

Thus, the second extraction results in two fractions, one being protein-enriched and the other being protein-depleted. Because the first extraction for removing the antinutritive substances has been carried out beforehand, both fractions can be processed to give the foodstuff and, in particular, cause no undesirable side effects, e.g. flatulence.

The protein yield may be increased by precipitating, in the extract originating from the first, acidic extraction, the residual protein constituents which are dissolved therein, for example by heat precipitation, adding alcohol and the like. Subsequent separation, for example by means of a centrifuge, gives a proteincontaining sediment which, for further processing, is returned to the first, acidic extraction step, by which any residues of alkaloids or other antinutritive substances are removed from this sediment and from the raw material for extraction. The total raffinate arising both from the plant raw material and the said sediment is then processed further together.

As was the case with the abovementioned protein precipitation, the extract from the first, acidic extraction may also be subjected to ultrafiltration (if appropriate in combination with protein precipitation) and the resulting residue can be returned to the first, acidic extraction.

One or both of the abovementioned extractions are advantageously carried out in more than one step, a countercurrent method preferably being employed. Such extraction methods, in which the extractant is concentrated stepwise and the raffinate obtained from the extraction steps in question is depleted stepwise in countercurrent, are already known. In the first (acidic) extraction, a nine-stage procedure resulted in a good Syield when extracting the antinutritive substances. In the second (alkaline) extraction, i.e. when extracting 7 the proteins, a two-step process has proved advantageous.

Separation of the suspensions during extraction is preferably effected by means of gravity or by means of mechanical separation, for example by sedimentation, centrifugation, filtration, expressing and the like.

As indicated above, the above-described second extraction yields two fractions. On the one hand, a protein-enriched protein milk is present, while on the other hand, a solid raffinate is obtained, which, when it contains a certain remainder of proteins, is enriched with valuable, i.e. fermentable, fiber. This raffinate can be used directly in the foodstuffs sector for adding fiber, for example in baked goods, drinks, sausage, fresh products or the like.

Depending on the original plant material, the protein milk may contain a certain amount of fat. It is recommended to remove at least part of this fat, and it would seem that mechanical fat separation, for example by means of a centrifuge, would be the least harmful method in the foodstuffs sector since no chemicals whatsoever are added. Besides, fat separation may already be effected before or during one or more extraction steps of the first extraction and/or also before or during one or more extraction steps of the second extraction.

The other fraction from the second extraction is a protein-containing milk. Plant-based fresh products similar to cheese, yoghurt, quark and the like may be obtained from this protein milk by further processing.

Alternatively, the protein milk may also be processed further to give a protein concentrate or protein isolate. To this end, protein precipitation is preferably carried out, for which purpose, for example, enzyme precipitation, precipitation by means of coagulants, heat and/or acid precipitation are suitable, in each case alone or in any combination with each other.

A membrane separation process could also be applied for protein isolation or protein concentration.

In an advantageous embodiment of the invention, the proteins are precipitated with acid, if appropriate 8 followed by heat precipitation.

Suitable coagulants would be, for example, CaSO 4 MgSO 4 Na 2

SO

4 or organic substances such as glucano- [lacuna] -lactone [sic].

Thus, a highly concentrated protein-containing product is obtained after drying of the constituents which have been precipitated. This protein-containing product, in turn, is outstandingly suitable for use in the foodstuff and animal feed sector. However, it may also be used wherever proteins are used, for example in the pharmacology sector or in the sector of the so-called industrial proteins, in particular for the production of biodegradable polymers or building materials, for example for films, adhesives, colors and the like.

The functionality, i.e. the effect on the chemico-physical behavior of systems, for example food systems, of the protein isolate or protein concentrate and of all other intermediates or end products which have been described can be influenced as early as during one of the two extractions, preferably the second, i.e.

alkaline, extraction from the original plant material.

This influencing of the functionality plays a role in adapting the proteins for their specific requirements. To alter the functionality, it is possible, for example, to add additives or to vary process parameters such as temperature, pH and the like. Suitable added chemicals are oxidants, substitution agents, metal ions (in particular divalent metal ions, such as, for example, Ca") or similar.

It is furthermore possible to cleave not only the protein milk, but also the protein concentrate or protein isolate obtained therefrom, by means of hydrolysis, for example enzymatic hydrolysis, acid hydrolysis and the like. The resulting hydrolyzate which, if appropriate, may still require purification, evaporation and/or drying, may be used, in turn, in a wide range of sectors, for example, in foodstuffs or in industry as indicated above. In the foodstuff sector, it may be used for Smaking, inter alia, sports products or anabolic products 9 for invalids.

By choosing one or more particular enzymes and/or microorganisms, the proteins can be cleaved selectively.

If purification is required to obtain a specific hydrolyzate, this can be effected, for example, by means of a membrane separation process.

It must also be mentioned that the product obtained after the abovementioned protein precipitation is a liquid whey which contains a remainder of proteins, these proteins being highly water-soluble. Even these highly water-soluble proteins may be obtained if so required, for example by means of a membrane separation process, in particular ultrafiltration. They can either be utilized immediately or processed further. If required, they may also be added to the protein isolate or protein concentrate obtained in the protein precipitation.

An exemplary embodiment of the invention is shown in the drawing and is illustrated in greater detail in the description which follows.

The figures show: Fig. 1 a block diagram which illustrates the preparation of the original plant material prior to carrying out the extractions according to the invention; Fig. 2 a block diagram which shows how a variety of fractions can be obtained from the original plant material in the two extractions according to the invention; Fig. 3 a block diagram which illustrates the processing of a raffinate obtained from an extraction to give a saleable product; Fig. 4 a block diagram, which shows the processing of a protein milk according to the invention, and Fig. 5 a block diagram which illustrates the 10 manufacture of fresh products.

The process sequence is described hereinbelow with reference to the processing of lupin seeds. As already mentioned, other protein-containing plants and in particular not only plant seeds can be processed in the same manner.

The process of Fig. 1 starts with lupin seeds 1 ready for use which have, if appropriate, previously been subjected to cleaning to remove stones, sand or other foreign objects. A magnetic separation of ferric constituents which may conceivably contaminate the lupin seeds during automatic harvesting, transport and storage is carried out.

The lupin seeds 1 are husked in a husking operation 2. This can be effected for example by means of a lower-runner or upper-runner husking operation, or by means of an impact husker. It has proved advantageous to grade the lupin seeds according to size prior to husking.

The husks are separated from the kernels via a husk separator and either subjected to intermediate storage or further processed. The kernels are then ground, for example by means of a cylinder mill, in a grinding operation 3 with intermediate sifting until the particle size is within the desired particle size spectrum. In the event that the lupin flour still contains husk constituents, these may be separated off via a pneumatic sifter, if so required.

The subsequent blanching 4 serves to inactivate enzymes. As already mentioned, it is in particular the lipoxygenase that is inactivated and which might otherwise cause the fats present in the lupin flour to be oxidized as mentioned above. The blanching operation 4 is carried out by means of steam, the temperature-time-load being chosen in such a way that the lupin proteins retain their native form. It has proved advantageous to carry out the blanching operation at approximately 920C, at an ambient pressure of 1 bar for a period of approximately 2 minutes. Blanching can be effected for example in a continuously operated belt blancher, which guarantees a 11 continuous and mild product mass stream.

After the blanching operation 4, the blanched flour is ready for the extractions 5 according to the invention.

The broken lines in Fig. 1 furthermore show that even the husks which have been separated off can be subjected to a grinding operation 6 and that they can be fed to the extraction process 5 according to the invention after a blanching operation, just like the kernels.

The entire process which takes place after husking, however, is to be carried out separately for the kernels and the husks. Fig. 1 must not be misunderstood in such a way that only the grinding processes 3 and 6 would proceed separately. Processing the husks in analogy to the following process, which is described for the kernels, results in a fiber concentrate or fiber isolate, as will be illustrated further below.

The process steps in accordance with Fig. 2 start from a raw material 7 as is obtained from the abovedescribed blanching operation 4 of the lupin flour from the ground kernels. This raw material 7 is subjected to a first extraction 8. This first extraction is to be carried out in an acidic medium with fresh drinking water as the solvent. The pH should be around the isoelectric point of the lupin proteins, i.e. around 4.5. The pH may be adjusted for example by means of sulfuric acid (H 2

SO

4 and/or phosphoric acid (H 3 P0 4 It has emerged that such a process, in particular with a countercurrent extraction in more than one step, allows alkaloids and other antinutritive substances such as the already repeatedly mentioned oligosaccharides to be extracted from the raffinate, apart from traces which are immaterial. Countercurrent extraction can be carried out in a stirred-vessel cascade. Each step comprises a stirred container with stirring equipment, a decanter and a pump for feeding the decanter. The stirred containers are preferably linked to a cooling device so as to dissipate from the process the energy which has been Sintroduced via the decanter. This extraction is operated 12 with cold water (for example at a temperature of between 0 C and 25 0 C) so that the lupin proteins retain their native form and that the solubility of the proteins is kept lower in order to increase the protein yield.

The countercurrent extraction, which comprises, for example, nine stages, is effected in such a way that the lupin flour enters in stage one and the solvent (fresh drinking water) in stage nine of the extraction.

The flour from stage one, which is depleted in antinutritive substances, is then passed on to stage two. The solvent from stage nine, which is enriched slightly with antinutritive substances, is used in the further depletion of the flour in stage 8. In general, it can be said that in each case the flour from extraction stage n is passed to extraction stage n 1, while the solvent is fed in countercurrent from extraction stage n to extraction stage n 1. The extract containing the antinutritive substances thus leaves the extraction from stage one, while the extracted raffinate is generated in stage nine of the extraction. As a consequence, a flour/solvent suspension is made up by stirring in each of these stages, and then again separated into a raffinate (moist solid) and extract (aqueous plant extract) Extract 9 thus contains the essential components of the antinutritive substances, while raffinate 10 is a product of vegetable origin which contains a valuable proportion of proteins and of digestible fiber. This raffinate 10 may already be used in fortifying foodstuffs or animal feeds with protein and fiber. Possible further processing to give a ready-to-sell product is illustrated further below.

In accordance with the invention, the raffinate can be digested further with a second extraction 11.

In the present exemplary embodiment, this extraction is also carried out with water as the solvent, but an alkaline environment must be ensured. Care must be taken that the maximum solubility for the protein extraction is around a pH of 8.5 or above.

However, as indicated above, the pH may be varied 13 in order to vary the functionality of the proteins to adapt them to specific applications of the end products of the process described. Variation of the functionality of the end products may also be effected by altering the process temperature or by adding additives. The abovementioned measures for altering the functionality may differ at each extraction stage.

The pH may be adjusted for example by adding NaOH, Ca(OH) 2 and/or KOH, the two last-mentioned substances being preferable for use in foodstuffs, since foods already contain a large amount of sodium.

The second extraction may also be carried out using cold water of 150C 250C. Again, this guarantees that the proteins are not denatured.

However, in the present exemplary embodiment, protein extraction is also carried out in a countercurrent process, albeit in two stages. The abovementioned measures for altering the functionality may be applied analogously to the second extraction too.

At the end of this second extraction, a raffinate 12 is present which is high in fiber, while extract 13 represents a protein milk which is high in proteins.

Both the raffinate 10, which originates from the first extraction 8, and the raffinate 12 of the second extraction 11 may already be used immediately as raw material for the production of foodstuffs or animal feeds.

To arrive at a ready-to-sell product, the raffinates are advantageously subjected to the following process steps, which are illustrated with reference to Fig. 3.

The starting point is in each case raffinate or 12, which is the direct product of the appropriate extraction, and this raffinate is subsequently dried 33.

If required, this may be followed by a grinding process 34 and/or a cooling phase 35. The end product from raffinate 10 or 12 which has thus been processed and which is in the form of a powder or coarse meal can subsequently be packaged 36, for example bagged. Thus, there already exist two end products of the process 14 according to the invention which can be utilized further and which differ from each other by a different ratio between fiber content and protein content.

The protein milk 13, which is the product from the second (alkaline) extraction 11, may be used for manufacturing a wide range of protein-containing products. The process sequence in accordance with Fig. 4 illustrates the various process branches in a simplified manner. For example, various fish [sic] products 14, such as yoghurt, quark, cheese and many others, may be prepared from the protein milk. The basic process sequence will be discussed further below.

Another processing option is to cleave the proteins of the protein milk by means of enzymatic hydrolysis. Depending on the choice of enzyme, functionspecific hydrolyzates 15 can be obtained. If appropriate, a purification step may be inserted. Such peptides, which have been obtained selectively by choosing the enzymes (proteases) in question, can be used, inter alia, in the foodstuffs sector, for example for sports products or for anabolic products for invalids. The hydrolyzates 15, in turn, can be marketed in dried form as powders, but also in liquid form.

The proteins of the protein milk 13 may also be obtained in concentrated form. To this end, they have to be separated from the whey. To separate off the proteins, they can be subjected, for example, to a protein precipitation 16. As already mentioned, the protein precipitation 16 can consist of a heat precipitation or an acid precipitation or a combination of the two types of precipitation. Thus, separation, for example with the aid of a centrifuge, gives a whey which only contains proteins which are highly soluble in water, and a moist protein-containing solid bulk. Another method of separating off the proteins consists in a membrane separation process 18, for example an ultrafiltration. Again, this immediately gives a moist protein-containing product.

The whey which results from the two processes, the ultrafiltration 18 and in particular the protein 15 precipitation 16 with separation 17, in turn, can be subjected to an ultrafiltration 19 to obtain the proteins which are highly soluble in water. These are subsequently added to the moist solid product which has previously been obtained, as shown in the diagram. However, they can also be used separately for a specific purpose.

The moist solid bulk, in turn, can be used for obtaining a fresh product 14 in the form of a set quark, for example by expressing. Fig. 4 shows this by a branch in the flow diagram, which leads to the fresh products 14.

The moist protein isolate or protein concentrate, which originates from the preceding process steps, can be processed to a dry product by a drying operation 20, for example a spray drying operation with a fluidized bed arranged downstream, a subsequent cooling phase 21 being provided, if so required, and bagged 22 as a commercial product. If appropriate, additives 23 are added at any desired point, for example prior to drying 20, to neutralize the protein isolate or protein concentrate, or to alter the functionality.

The protein isolate or protein concentrate resulting from the process sequence of Fig. 4 can be used in a variety of ways in the foodstuffs or animal feed sector. Naturally, the abovementioned fresh products 14 may also be prepared readily from the dry product 22. As a rule, however, it is less complicated to produce the fresh products 14 directly from the protein milk 13, since this dispenses with a drying step. Equally, the dry product is available for a hydrolysis 15, but, again, the direct use of the protein milk 13 represents a less complicated process, for the same reasons.

The protein isolate or protein concentrate can be used not only in the foodstuffs and animal feed sector, but also in the industrial protein sector. As mentioned above, suitable for this purpose are building materials or polymers, for example colors, adhesives, films and the like. The lupin protein behaves similarly to casein, which is known from cows' milk, which again has been used 16 not only in the food sector, but also for industrial products, for example colors.

Furthermore, it must be mentioned that the lupin milk can also be used directly under certain circumstances. An example for the necessity of a milk replacement is the so-called lactose allergy, which occurs occasionally, which means that affected persons cannot ingest any lactose-containing products from cows' milk.

This may be remedied with the protein milk under certain circumstances. Not only the protein milk as such, but also the plant-based fresh products 14, which have already been mentioned, represent an alternative in such a case.

The fresh products 14 can be produced (see Fig. 5) by processes which are analogous to the processes known from cows' milk processing. Thus, the protein milk 13 can be subjected either to precipitation with lactic acid bacteria 25 or else to enzymatic precipitation 26 (so-called rennet precipitation), if appropriate with an addition of additives 24, such as minerals or carbohydrates.

The precipitation with lactic acid bacteria if appropriate again with the addition of other additives 24, for example again carbohydrates and minerals, results in products which are similar to yoghurt 27, quark 28, cultivated sour milk 29 and various types of soft cheese or cream cheese 30. The enzymatic precipitation gives a quark 31, which can be processed to hard cheese 32, either with or without additives 24.

In addition to the abovementioned types of food, all protein products which are known from soya bean processing may also be produced. The following may be mentioned as examples: tofu or tofu-like products or else the so-called tempeh, which can be obtained after a controlled incubation period from a mixture of protein quark and fungal spores.

The protein isolate or protein concentrate has already been used successfully as a replacer when making processed cheese. It was possible to replace a consider- -17able proportion of Gouda cheese which is normally used as a starting material for processed cheese, by a protein isolate or protein concentrate according to the invention.

The above-described process stages have given rise to solid and liquid products which have a wide range of protein/fiber ratios. Amongst the products described up to here, the raffinate 12, which originates from the second extraction according to the invention, was highest in fiber.

However, if the husks which are separated off in the husking operation 2 (Fig. 1) are subjected to the same process steps as described above and which are shown by the broken lines in Fig. 1, in particular at least one of the two extractions 8 and 11, then a product which contains almost exclusively fiber is obtained in place of the raffinate 12.

All essential antinutritive substances have been removed virtually completely from this fiber concentrate or fiber isolate by the extractions according to the invention, in particular the first extraction 8.

When processing the husks, extraction in a neutral environment or without setting 15 a specific pH may give the desired fiber concentrate or fiber isolate, depending on the original plant material, if the husks no longer contain substantial amounts of protein.

It will be understood that not each specific use and each specific end product can be described in detail because of the diversity of all possible end products from the.

proposed process for processing protein-containing plants or plant seeds. What is 1 20 essential, however, is the removal of the antinutritive substances, which is why not only the above-described protein isolates or protein concentrates, but also the fiber concentrates and fiber isolates, or else mixtures of fiber and proteins represent easily digestible products.

Throughout the description and claims of the specification the word "comprise" and variations of the word, such as "comprising" and "comprises" is not intended to exclude other additives, components, integers or steps.

195-96.OC

Claims (18)

1. A process for processing protein-containing and alkaloid-containing plants or parts thereof, such as lupins or the like, and in particular the seeds of these plants, which comprises carrying out at least two separate extractions with water as the extractant, where antinutritive substances are extracted in one extraction and proteins are extracted in the other extraction and where both extractions are performed under atmospheric pressure.

2. The process as claimed in claim 1, wherein the plants and/or plant parts, such as plant seeds and the like, are comminuted.

3. The process as claimed in one of the preceding claims, wherein the material is comminuted to such an extent that it has the structure of a course meal.

4. The process as claimed in any of the preceding claims, wherein enzymes are inactivated. The process as claimed in any of the preceding claims, wherein plant seeds are 15 husked.

6. The process as claimed in one of the preceding claims, wherein lupins and/or parts of lupins are processed. C

7. The process as claimed in any of the preceding claims, wherein at least one extraction is carried out with water as the extractant.

8. The process as claimed in any of the preceding claims, wherein in both extractions water is used as the extractant, antinutritive substances being extracted in the first extraction in an acidic medium and proteins in the second extraction in an alkaline medium.

9. The process as claimed in any of the preceding claims, wherein the pH in the first (acidic) extraction is in the range of from 3.5 to The process as claimed in any of the preceding claims, wherein the pH in the second (alkaline) extraction is greater than

11. The process as claimed in any of the preceding claims, wherein at least one extraction is performed in more than one step by the countercurrent method.

12. The process as claimed in any of the preceding claims, wherein fat is separated off mechanically. CAkWINWORDWICHELLE\SPECIES 7695-9.OOC -19- r

13. The process as claimed in any of the preceding claims, wherein proteins are obtained by a membrane separation process and/or precipitated from the protein milk obtained.

14. The process as claimed in any of the preceding claims, wherein the functionality of at least one of the end products is varied by adding additives, selecting the process temperature and/or adjusting the pH during at least one extraction stage of at least one of the two extractions. A fiber-fortified plant product from protein-containing plants or parts thereof when prepared by a process according to any of the preceding claims, wherein at least some of the antinutritive substances and/or proteins have been extracted.

16. A plant-based, in particular lupin-based, protein milk when prepared by a process according to any of claims 1 to 14, wherein at least some of the antinutritive substances have been extracted.

17. A protein-containing product which can be prepared from a protein milk as claimed in claim 16.

18. A protein hydrolyzate which can be prepared from a protein milk of claim 16 :and/or from a protein-containing product of claim 17.

19. A fresh product as claimed in any of the preceding claims, which can be prepared at least partially from a protein milk as claimed in claim 16 and/or a protein-containing product as claimed in claim 17.

20. A fiber- and protein containing product from processing protein-contaiiling plant seeds such as lupin seeds, soya beans and the like when prepared by a process according to any of claims 1 to 14, where antinutritive substances are removed in an extraction, which comprises husking the plant seeds prior to extraction.

21. A process according to claim 1 substantially as hereinbefore described with reference to any of the figures. DATED: 28 January, 2000 PHILLIPS ORMONDE FITZPATRICK ttdm R;A CONSU AG and FRAUNHOFER-GESELLSCHAFT ZUR .FORDERUNG DER ANGEWANDTEN FORSCHUNG E.V.