METHODS OF PROCESSING A FAVA BEAN COMPOSITION

Abstract

A method of processing a fava bean composition is disclosed, the method comprising the steps of: i. providing a fava bean composition comprising fava beans, and ii. subjecting the fava bean composition to a betaglucosidase and at least one lactobacillus plantarum bacteria under dosage, time and temperature conditions selected so as to be sufficient to reduce the content of at least one of the compounds vicine and convicine, and preferably also at least one of the compounds divicine and isouramil, by at least 90 wt % as compared to the content of said compounds in the fava bean composition provided in step i. A fava bean composition obtained by the method as well as methods of producing food compositions using the fava bean composition and food compositions thus produced are also disclosed.

Claims

1. A method of processing a fava bean composition, comprising the steps of: i. providing a fava bean composition comprising fava beans, and ii. subjecting the fava bean composition to a betaglucosidase and at least one lactobacillus plantarum bacteria under dosage, time and temperature conditions selected so as to be sufficient to reduce the content of at least one of the compounds vicine and convicine, and preferably also at least one of the compounds divicine and isouramil, by at least 90 wt % as compared to the content of said compounds in the fava bean composition provided in step i.

2. The method according to claim 1, wherein the fava bean composition provided in step i has been heat treated for reducing the microbial content or for sterilizing the fava bean composition, or wherein the method further comprises a step of: iii. heat treating the fava bean composition for reducing the microbial content of the fava bean composition or for sterilizing the fava bean composition.

3. The method according to claim 1, wherein the fava bean composition provided in step i comprises crushed, milled and/or homogenized fava beans in an aqueous liquid, and wherein the dry matter content of the fava bean composition preferably is from 5 to 20%, preferably 5 to 15%, such as 7 to 12% or 8-10%.

4. The method according to claim 1, wherein the dosage, time and temperature conditions are selected so as to be sufficient to decrease the sum content of vicine and convicine in the fava bean composition to less than 6 wt %, preferably less than 2 wt %, more preferably less than 1 wt % of the sum content of said compounds in the fava bean composition provided in step i, or alternatively selected so as to be sufficient to decrease the sum content of vicine and convicine in the fava bean composition to less than 65 mg/kg, preferably less than 22 mg/kg, more preferably less than 12 mg/kg of the fava bean composition.

5. The method according to claim 1, wherein the dosage, time and temperature conditions are selected so as to be sufficient to decrease the sum content of divicine and isouramil in the fava bean composition to less than 150 mg/kg of the fava bean composition, preferably less than 50 mg/kg of the fava bean composition, more preferably less than 10 mg/kg of the fava bean composition, such as less than 1 mg/kg of the fava bean composition, such as less than 0.1 mg/kg or less than 0.01 mg/kg of the fava bean composition.

6. The method according to claim 1, wherein step ii comprises subjecting the fava bean composition to the betaglucosidase, wherein the dosage is at least 0.1 wt % based on the amount of the fava bean composition, and wherein the time and temperature conditions are at least 2 hours and at least 60° C.

7. The method according to claim 1, wherein step ii comprises subjecting the fava bean composition to the at least one lactobacillus plantarum bacteria, wherein the dosage is at least 0.01 wt %, such as 0.01 to 0.1 wt % based on the amount of the fava bean composition, and wherein the time and temperature conditions are at least 10 hours, such as at least 12 hours, and at least 35° C.

8. The method according to claim 1, wherein the fava bean composition is subjected to the betaglucosidase under first dosage, time and temperature conditions, and subjected to the lactobacillus plantarum bacteria under second dosage, time and temperature conditions.

9. The method according to claim 8, wherein step ii comprises subjecting the fava bean composition simultaneously to the betaglucosidase and the at least one lactobacillus plantarum bacteria, and wherein the first and second time and temperature conditions are the same, and wherein preferably the first and second time and temperature conditions are at least 10 hours, such as 10-16 hours, and at least 35° C., such as 35-40° C., preferably 37-39° C. or 38° C.

10. The method according to claim 1, wherein the at least one lactobacillus plantarum bacteria is L. plantarum 299 or L. plantarum 299v.

11. The method according to claim 8, wherein the first and second dosage, time and temperature conditions are selected so as to be sufficient for reducing the total sum content of vicine, convicine, divicine and isouramil, calculated using the formula:
total sum content=sum content of vicine and convicine 30 30*sum content of divicine and isouramil to less than 1500 mg/kg of the fava bean composition, preferably less than 340 mg/kg of the fava bean composition.

12. The method according to claim 1, further comprising the step of: v. collecting a solid fraction of the fava bean composition, such as by decanting, whereby the remainder of the fava bean composition defines a liquid fraction of the fava bean composition.

13. A fava bean composition obtained by the method according to claim 1.

14. A method of manufacturing a food product or a feed product comprising using the fava bean composition according to claim 13.

15. A food product or feed product obtained by the method according to claim 14.

Description

BRIEF DESCRIPTION OF THE FIGURES AND DETAILED DESCRIPTION

[0078] A more complete understanding of the abovementioned and other features and advantages of the technology proposed herein will be apparent from the following detailed description of preferred embodiments in conjunction with the appended drawings, wherein:

[0079] FIG. 1A shows inter alia a first embodiment of the method of processing a fava bean composition according to the first aspect of the technology proposed herein,

[0080] FIG. 1B shows inter alia a second embodiment of the method of processing a fava bean composition according to the first aspect of the technology proposed herein

[0081] In the below description of the figures the same reference numerals are used to designate the same features throughout the figures. Further, where present a ′added to a reference numeral indicates that the feature is a variant of the feature designated with the corresponding reference numeral not carrying the ′-sign.

[0082] FIG. 1A shows inter alia a first embodiment of the method of processing a fava bean composition according to the first aspect of the technology proposed herein. As shown in the figure fava beans 2 and water 4 are admitted to a mill 6 in which the fava beans are milled and finely divided together with the water. The fava beans are disintegrated to particles less than 5 mm in diameter. The milling in the mill 6 may take place at any suitable temperature. Typically the temperature is at least 20° C. The temperature may be higher, such as at least 70° C. or 90° C., for example 95° C. temperature. The milling continues until of the fava beans 2 have been reduced in size to the size provided by the mill 6, i.e. less than 5 mm diameter. The mixture of milled fava beans, i.e. the fava bean material, and water is hereinafter referred to as a fava bean composition. The fava bean composition here has a dry matter content of about 9 wt %. The fava bean composition may optionally, after the mill 6, be homogenized in a homogenizer 8 at elevated pressure and temperature, for example at more than 70° C. or more than 80° C. and at more than 100 bar or any other pressure suitable to further disintegrate the fava bean material in the fava bean composition and to increase the degree of extraction of the nutrients (carbohydrates, proteins, minerals, vitamins, etc.) from the fava bean material.

[0083] The fava bean composition is then decanted in decanter 10 for separating out a solid fraction 12 of the fava bean composition. This solid fraction 12 may be used as described further below.

[0084] The remainder of the fava bean composition, the liquid fraction 14, is transferred into a mixing tank 16. In order to reduce the content of the compounds vicine, divicine, convicine and isouramil in the liquid fraction 14 a betaglucosidase enzyme 18 is added to the mixing tank 16. The addition of the enzyme 18 is typically 0.1 to 1 wt % of the fava bean composition and the enzyme is allowed to process the liquid fraction 14 for about at least 1 hour, such as for example 2-4 hours and at a temperature, such as from 40-70° C., for example from 55 to 65° C., at which the enzyme is active. The enzyme may, as here, be provided as a solution containing 20 wt % enzyme, whereby the dosage of 0.1 to 1 wt % refers to the enzyme solution and corresponds to 0.02 to 0.2 wt % of isolated enzyme being added.

[0085] The so treated liquid fraction comprises a reduced content of at least one of the compounds vicine and convicine.

[0086] Optionally, to reduce the microbial content, the liquid fraction may for example be heat treated, for example as illustrated here using an UHT device 20 wherein it is heat treated at temperatures above 100° C. for sufficient time.

[0087] If then enzyme is not inactivated in the UHT device 20, then the enzyme may be deactivated in the mixing tank 16, after the enzymation process has concluded by cooling the mixing tank 16 to a temperature below room temperature, or alternatively be heating the mixing tank 16 to a temperature sufficient to cause heat denaturing of the enzyme.

[0088] Optionally the liquid fraction 14 may be homogenized in a second homogenizer 22 before being stored, for example in a sterile tank 24, or used further.

[0089] The liquid fraction 14 of the fava bean composition so obtained may be used as a substitute to cream and whipping cream, as a base for soups etc.

[0090] The solid fraction 12 may be used as a meat substitute.

[0091] Both the solid fraction 12 and the liquid fraction 14 contain reduced contents of the compounds vicine, divicine, convicine and isouramil as compared to the fava beans 2 in the beginning of the process.

[0092] Although in FIG. 1A only the liquid fraction 14 enters the mixing tank 16 to be enzymated using the enzyme 18, it is also possible to position the decanter 10 after the mixing tank 16 such that the enzymation using the enzyme 18 is performed on the fava bean composition prior to the separation of the fava bean composition into the solid fraction 12 and the liquid fraction 14.

[0093] Further, whereas FIG. 1A (and 1B below) show and describe the use of a number of devices and steps, including the mill 6, the homogenizer 8, decanter 10, UHT device 20, homogenizer 22, sterile tank 24, which are advantageous, these devices and steps are not essential for achieving the objects of the technology described herein.

[0094] FIG. 1B shows inter alia a second embodiment of the method of processing a fava bean composition according to the first aspect of the technology proposed herein. This embodiment differs in that, in addition to the enzyme 18 and the following enzymation in the mixing tank 16, fermentation is also performed in the mixing tank 16 following the addition of a lactobacillus plantarum strain bacteria 26 (L. plantarum 299). Specifically Lactobacillus plantarum DSM 9843 can be used.

[0095] In a first alternative embodiment the bacteria 26 is added prior to the addition of the enzyme 18. The liquid fraction 14 is thus allowed to ferment for 12-24 hours (preferably 12 hours) at a temperature of 35-40° C. (such as 38° C.). Thereafter the enzyme 18 is added and the enzymation takes place at 30-70° C. (such as 60° C.) for a time of 1-12 hours (such as 2 hours).

[0096] In a second alternative embodiment the bacteria 26 is added at the same time as the enzyme 18. The liquid fraction 14 in the mixing tank 16 is then simultaneously fermented and enzymated for at least 6 hours at a temperature of 35-40° C. (such as 38° C.).

[0097] In certain cases it may be desired to further adjust or increase the nutritious properties of the fava bean composition. Edible oil, such as rape seed oil, may in particular be added to the mixing tank upon conclusion of the enzymation and fermentation.

[0098] This option is illustrated in FIG. 1B by the addition of edible oil 30 either in the beginning of the process, or the addition of edible oil 32 to the mixing tank 16. Edible oil may additionally be added at other steps of the method.

[0099] Other foodstuffs may also be added to the fava bean composition. One example is oats and other cereals. Foodstuffs may in particular be added prior to the addition of the enzyme 18 and or the bacteria 26, for example as indicated by 34 in FIG. 1B.

EXAMPLE

[0100] Table 1 disclose the results obtained on reducing the content of vicine, divicine, convicine and isouramil in a fava bean composition (liquid fraction) dependent on the treatment method used.

[0101] The content of the compounds was determined as follows.

[0102] Vicine and convicine were determined as based on the method described by Gutierrez et al: CAPs markers to assist selection for low vicine and convicine contents in faba bean (Vicia faba L.). Theor. Appl. Genet. 2006. The samples were extracted with water in a hot water bath for 3.5 hours, after which concentrated HCl was added to the sample extracts. Samples were analyzed by an Agilent 1100 series high performance liquid chromatography device with a diode array detector (HPLC-DAD). A C18 column was used with a gradient of phosphate buffer and methanol. The breakdown products divicine and isouramil were identified by their UV-spectra and quantitated using a calibration curve of vicine and correcting the result by molar mass ratio.

[0103] For samples no. 2-6, the respective methods were carried out as described in table 1, and samples for the analysis above were collected about 24 hours after conclusion of the enzymation and fermentation step(s). The collected samples were then frozen, stored for 1-2 weeks, and then thawed before being extracted with water and further prepared for analysis as described above.

[0104] The results listed in table 1 are typical values from several runs of each of the respective methods (sample no. 2-6), and from several samples collected from each run.

TABLE-US-00001 TABLE 1 Sample no. Method/sample Contents Comment 1 Freshly harvested fava In total about 10740 Reference value for a non- bean mg/kg of convicine processed fava bean. and vicine Divicine and isouramil are degradation products/metabolites of convicine and vicine, and therefore not present in any significant amount in the fava bean. 2 Fava bean composition 360 mg/kg of The fava bean composition as formed according to convicine comprises a lower content FIG. 1A but without the 791 mg/kg of vicine of convicine and vicine enzymation step. (in total about 1079 compared to the freshly (Temperature of fava mg/kg of convicine harvested fava bean. This bean composition and vicine) is due to the dilution during processing Less than 2 mg/kg of effected by the addition of about 90° C.) divicine and isouramil the water 4. In this case the ratio of fava bean:water was about 1:9. Although the content of convicine and vicine has been reduced compared to the freshly harvested fava bean, it however needs to be further reduced. 3 The liquid fraction 5 mg/kg of convicine This process provides a obtained as shown in 68 mg/kg of vicine significant reduction of FIG. 1A, i.e. using only divicine could not be convicine and vicine. A enzymation. detected (less than 2 total reduction of about 93% (The temperature of mg/kg) has been obtained fava bean composition isouramil could not (corresponding to ((5 mg + in the steps up to the be detected (less 68 mg)/1079 mg)). No enzymation was about than 2 mg/kg) divicine or isouramil could 90° C. Enzymation be detected in the fava using 0.25 wt % dosage bean composition. of betaglucosidase (activity of 1500 AZO BBG U/g or 6200 IU/g) for 2 hours at 60° C.) 4 The liquid fraction 12 mg/kg of This process reduces obtained as shown in convicine convicine and vicine more FIG. 1A with the 4 mg/kg of vicine than the process using difference that In total 134 mg/kg of enzymation; however the fermentation alone was divicine and isouramil content of divicine and used instead of isouramil has increased. enzymation. A total reduction of about (The temperature of 86% has been obtained fava bean composition (corresponding to ((12 mg + in the steps up to the 4 mg + 134 mg)/1079 mg). fermentation was about 90° C. Fermentation using 0.02 wt % dosage for 12 hours at 38° C.) 5 The liquid fraction 2 mg/kg of convicine, The sequential obtained as shown in 21 mg/kg of vicine, fermentation and FIG. 1B: first alternative In total 46 mg/kg of enzymation reduces the in which fermentation divicine and isouramil content of convicine and and enzymation are vicine further in performed sequentially. comparison to enzymation (Temperature of fava only, however the sum bean composition in the content of divicine and steps up to isouramil is higher. fermentation was about A total reduction of about 90° C. fermentation: 93% has been obtained 0.02 wt % for 12 hours (corresponding to ((2 mg + at 38° C.), enzymation: 21 mg + 46 mg)/1079 mg) 0.25 wt % for 2 hours at 60° C.). 6 The liquid fraction 10 mg/kg of Concurrent enzymation obtained as shown in convicine, and fermentation yields the FIG. 1B: second 2 mg/kg of vicine, lowest contents of alternative in which In total no mg/kg of convicine and divicine, enzymation and divicine and isouramil together with a low sum fermentation performed could be detected content of divicine and concurrently. isouramil. (Temperature of fava A total reduction of about bean composition in the 99% has been obtained steps up to (corresponding to ((10 mg + fermentation was about 2 mg + 0 mg)/1079 mg) 90° C. Combined fermentation (0.02 wt %) and enzymation: 0.25 wt % for 12 hours at 38° C.)

[0105] Divicine and isouramil are about 30 times more potent in causing symptoms in individuals with G6PDD. Accordingly it becomes clear that at least an enzymation step using betaglucosidase is preferably used for processing the fava bean composition. The addition of the fermentation step, as shown in FIG. 1B, further decreases the content of convicine and vicine, especially when, as in sample 6, the enzymation is performed during the time that the fermentation is performed.

[0106] As stated above, the reported values for vicine, convicine, divicine and isouramil in table 1 were obtained from samples collected 24 hours after the enzymation and fermentation step(s), the collected samples also having been frozen and stored for 1-2 weeks before being thawed before analysis. It was further noted that the results for the compounds showed no significant variation between samples and runs for the same method (sample no-2-6).

[0107] Taking this into account, it appears that the compounds divicine and isouramil did not exhibit any significant spontaneous degradation during the time after the fermentation and enzymation step(s). Hence there exists a need for a method, i.e. the method according to the first aspect of the technology proposed herein, that is capable of also sufficiently reducing divicine and isouramil during the enzymation and fermentation.

[0108] The various aspects of the technology proposed herein and described above are further exemplified by the following points: [0109] 1. A method of processing a fava bean composition, comprising the steps of: [0110] i. providing a fava bean composition comprising fava beans, and [0111] ii. subjecting the fava bean composition to a betaglucosidase and/or at least one lactobacillus plantarum bacteria under dosage, time and temperature conditions selected so as to be sufficient to reduce the content of at least one of the compounds vicine and convicine, and preferably also at least one of the compounds divicine and isouramil, by at least 90 wt % as compared to the content of said compounds in the fava bean composition provided in step i. [0112] 2. The method according to point 1, wherein the fava bean composition provided in step i has been heat treated for reducing the microbial content or for sterilizing the fava bean composition, or wherein the method further comprises a step of: [0113] iii. heat treating the fava bean composition for reducing the microbial content of the fava bean composition or for sterilizing the fava bean composition. [0114] 3. The method according to any preceding point, wherein the fava bean composition provided in step i comprises crushed, milled and/or homogenized fava beans in an aqueous liquid. [0115] 4. The method according to any preceding point, wherein the dosage, time and temperature conditions are selected so as to be sufficient to decrease the sum content of vicine and convicine in the fava bean composition to less than 6 wt %, preferably less than 2 wt %, more preferably less than 1 wt % of the sum content of said compounds in the fava bean composition provided in step i, or alternatively selected so as to be sufficient to decrease the sum content of vicine and convicine in the fava bean composition to less than 65 mg/kg, preferably less than 22 mg/kg, more preferably less than 12 mg/kg of the fava bean composition. [0116] 5. The method according to any preceding point, wherein the dosage, time and temperature conditions are selected so as to be sufficient to decrease the sum content of divicine and isouramil in the fava bean composition to less than 150 mg/kg of the fava bean composition, preferably less than 50 mg/kg of the fava bean composition, more preferably less than 10 mg/kg of the fava bean composition, such as less than 1 mg/kg of the fava bean composition, such as less than 0.1 mg/kg or less than 0.01 mg/kg of the fava bean composition.. [0117] 6. The method according to any of the preceding points, wherein step ii comprises subjecting the fava bean composition to the betaglucosidase, wherein the dosage is at least 0.1 wt % based on the amount of the fava bean composition, and wherein the time and temperature conditions are at least 2 hours and at least 60° C. [0118] 7. The method according to any of the points 1-5, wherein step ii comprises subjecting the fava bean composition to the at least one lactobacillus plantarum bacteria, wherein the dosage is at least 0.01 wt %, such as 0.01 to 0.1 wt % based on the amount of the fava bean composition, and wherein the time and temperature conditions are at least 10 hours, such as at least 12 hours, and at least 35° C. [0119] 8. The method according to any preceding point, wherein step ii comprises subjecting the fava bean composition to both the betaglucosidase and the at least one lactobacillus plantarum bacteria, wherein the fava bean composition is subjected to the betaglucosidase under first dosage, time and temperature conditions, and subjected to the lactobacillus plantarum bacteria under second dosage, time and temperature conditions. [0120] 9. The method according to point 8, wherein step ii comprises subjecting the fava bean composition simultaneously to the betaglucosidase and the at least one lactobacillus plantarum bacteria, and wherein the first and second time and temperature conditions are the same. [0121] 10. The method according to any of the preceding points, wherein the at least one lactobacillus plantarum bacteria is L. plantarum 299 or L. plantarum 299v. [0122] 11. The method according to any of the points 8-10, wherein the first and second dosage, time and temperature conditions are selected so as to be sufficient for reducing the total sum content of vicine, convicine, divicine and isouramil, calculated using the formula:

total sum content=sum content of vicine and convicine+30*sum content of divicine and isouramil

to less than 1500 mg/kg of the fava bean composition, preferably less than 340 mg/kg of the fava bean composition. [0123] 12. The method according to any of the preceding points, further comprising the step of: [0124] v. collecting a solid fraction of the fava bean composition, such as by decanting, whereby the remainder of the fava bean composition defines a liquid fraction of the fava bean composition. [0125] 13. A fava bean composition obtained by the method according to any of the preceding points. [0126] 14. A method of manufacturing a food product or a feed product comprising using the fava bean composition according to point 13. [0127] 15. A food product or feed product obtained by the method according to point 14.