WO2012138582A1

WO2012138582A1 - Pulse dry cooking and hydration process

Info

Publication number: WO2012138582A1
Application number: PCT/US2012/031698
Authority: WO
Inventors: Janis Zakis
Original assignee: Pulstar International Corporation
Priority date: 2011-04-02
Filing date: 2012-03-30
Publication date: 2012-10-11

Abstract

A cooking and hydration system for whole seeds and pulses, including a dry friction cooker having a product inlet and a product outlet; a hydration system in fluid communication with said product outlet of said dry friction cooker, wherein said hydration system is airtight or includes an inert gas supply so as to maintain commercial sterility of the product being processed; a disintegrator mill in fluid communication with said hydration system, said disintegrator mill including a comminution screen defining a comminution screen portion within said disintegrator mill, a motorized mixer operatively coupled to a mixer blade in said comminution screen portion, and an disintegrator mill outlet; and optionally a pressure boosting hydration system in fluid communication with said disintegrator mill outlet and in fluid communication with a back pressure source applied to said pressure boosting hydration system through a back pressure valve.

Description

PULSE DRY COOKING AND HYDRATION PROCESS

BACKGROUND OF THE INVENTION

Technical Field

[0001] The present invention relates generally to food processing methods, and more specifically to a process for cooking and hydrating pulses, and still more particularly to an aseptic method of hydrating and cooking dry beans, dry broad beans, dry peas, chickpeas, lentils, and seeds.

Background Art

[0002] The commercial production of chickpea hummus is currently a $300 million business in the United States. World-wide commercial production is at least ten times that large. However, despite its importance in regional cuisine and as a staple food, the process of preparing hummus is time consuming and expensive, requiring considerable factory floor space.

[0003] The traditional method of producing chickpea puree to make hummus involves soaking raw chickpeas for up to 12 hours in excess water, then draining the soaked peas, adding new cooking water, and then cooking the chickpeas at close to 95 degrees C for up to an hour. The cooked chickpeas are then drained, ground, and chilled before being mixed with olive oil, spices, and tahini. These steps result in the Mediterranean dipping sauce called hummus.

[0004] The traditional industrial process utilized in large hummus production plants requires (a) considerable floor space to soak the beans, (b) an enormous amount of energy to heat and cook the chickpeas, and (c) excess water and additional energy to chill the beans before grinding. The production costs are thus very high, and the time needed for production is extensive. [0005] In recent years pressure cooking of the chickpeas has been used to shorten the cooking time, but the actual reduction in cooking time amounts to no more than about 30 minutes.

[0006] A second improvement was to convert the process from a batch to a continuous process. Using this method, the whole beans are first ground to reduce the particle size so that the soaking water penetrates more quickly to the center of the bean pieces; this reduced the time of the soaking step. The soaked, ground chickpeas are then heated under pressure to approximately 126 degrees C at 1.72 bar (25 psi), well over the atmospheric boiling point, and they are held at this temperature and pressure for 10 to 15 minutes. This pressure cooking process shortens overall processing time from approximately 13 hours to slightly over an hour.

[0007] The continuous system also reduces the energy required for producing the hummus, since the ground chickpeas and the water to be absorbed by the puree are all that are heated. In other words, there is no excess water heated in the process. However, since the water content of continuous pressure cooked hummus puree is a little more than two thirds of the total weight, heating of the water to about 126 degrees C still requires a considerable amount of energy. Cooling it down to 5 degrees C requires additional energy. While this system requires less time and less energy than the original traditional system, it is still an expensive process. Accordingly, there remained a need for an efficient and economical method of hydrating and cooking pulses.

[0008] As a step in solving the foregoing problems, the present inventor devised a predecessor invention to the present invention; namely, a dry friction cooking process for seeds and pulses. The process involves the introduction of whole, dry chickpeas (or other seeds or pulses) into a friction cooker. The dry chickpeas are cooked under pressures up to 40 atmospheres (580 PSI) and at temperatures between 100 degrees C (212 degrees F) and 200 degrees C (392 degrees F) using only friction to create the product pressure and temperature. The whole chickpea beans fed into the friction cooker are dry from the field with only 10- 12% natural moisture. No additional water is added in the process, and only the natural moisture in the chickpeas gelatinizes the starch. A granular, commercially sterile product is discharged from the friction cooker having between 4-6% moisture with the balance of the natural moisture flashing to steam. The starch granules in the discharged product are fully cooked (gelatinized) so the granular product can be hydrated with cold water. The product discharged from the friction cooker has been marketed as a cooked flour by milling the product with a rotary disintegrator. The flour is sold with a micron size of 150 micron or above (up to 2000 micron), depending on the desired smoothness of the customer's hummus.

[0009] Due to the economies of cooking chickpeas without adding water during the cooking process, the dry friction cooking process allows a producer to market a hummus product at a lower price. The water required for soaking is eliminated. In addition this process eliminates the energy required to heat and then chill the water absorbed into the chickpea puree. Only the water absorbed by the friction cooked flour after cooking is used, and this hydration water is added to the flour cold. Adding water cold minimizes the need to chill the chickpea puree down to the final hummus refrigerated temperature of 5 degrees C for storage.

[0010] The dry friction cooking process invention was a huge step in reducing the processing costs of hummus compared with the traditional process of soaking, cooking in excess water, and chilling with refrigeration. The invention in practice is less costly than grinding raw chickpeas and soaking and continuously cooking hummus puree in a pressure cooking system. However, the disadvantage of the dry friction cooking process is that the cooked flour is very difficult to hydrate because of the rapidity with which the flour absorbs hydration water. As with many hydroscopic powders, the friction cooked flour tends to lump up and leave lumps of flour called 'fish eyes' that do not hydrate properly. The 'fish eye' problem lowers yield and leaves unpleasant chunks of flour in the final product.

[0011] To overcome the mixing and hydration problems of dry friction cooked chickpeas, the hummus must be mixed in high speed mixers that pulverize the un-hydrated particles. In the alternative, the flour and water can be gradually added together in an atmospheric high speed mixer grinder. However, it is nearly impossible in both of these systems to keep air from being mixed into the product. And once air is introduced into the product, there is a high possibility of introducing pathogens, vegetative cells, and spores into the hummus product. These unwanted 'additives' reduce the shelf life and make preservatives or acids necessary to lower the pH to below 4.2 in order to provide a commercially practical refrigerated shelf life for the final product. [0012] In fact, all three of the above-described processes make a chickpea puree that requires the hummus to be formulated with higher acid content by adding lemon juice or other ingredients to lower the pH to less than 4.2. The processor also may have to add preservatives such as potassium sorbate. Lowering the pH or adding preservatives either changes the flavor of the hummus or makes it 'unnatural' because of the addition of the preservatives.

[0013] It is desirable to develop a production process that keeps the pathogen and live spore count low enough that a natural hummus can be made with a pH level above 4.2, preferably in a range between 4.2 and 4.8 pH, or above, and still have a refrigerated shelf life of 60 days or more.

[0014] There remains a need for the development of a process that will solve the above- described problems. A commercial hummus production system should have the following advantages: (1) no requirement for soaking chickpeas prior to cooking; (2) no requirement to cook the chickpea beans in excess water, thereby reducing the need to add heat energy; (3) uses only the amount of water absorbed in the hydration process so that there is no excess water drained off during processing; (4) eliminates the addition of water prior during the cooking process to reduce the energy requirements of heating the added water during cooking and then chilling the added water after cooking; (5) produces a puree that is commercially sterile with zero measureable pathogens and live spores; (6) maintains the commercially sterile condition throughout the downstream mixing and hydration process; and (7) eliminates any risk of introducing pathogens, vegetative, or live spores from the environment during the cooking and hydration process, thereby discharging a chickpea puree product into the aseptic mixing and packaging system that is essentially free of any cells or spores that can grow during a 60 day refrigerated shelf storage period. This will allow the formulation of the final hummus product with a pH above 4.2 with a natural flavor and without the need to add preservatives.

Disclosure of Invention

[0015] The present invention is a process for the cooking and hydrating of chickpea puree for the production of natural hummus. The inventive method involves friction cooking whole chickpeas without the addition of water, while simultaneously hydrating and grinding the dry, cooked chickpeas continuously without exposing the product to the environment. This process dramatically reduces the steps required and results in dramatically reduced energy and water requirements compared to the above-described traditional processes. The resulting chickpea puree can be mixed with olive oil, tahini, and spices to make a product with a pH above 4.2, which can be safely refrigerated for more than 60 days without the addition of preservatives.

[0016] It is a first and principal object of the invention to eliminate the requirement of soaking chickpeas prior to cooking.

[0017] Another object and advantage of the present inventive system is that it adds only the amount of water absorbed in the hydration process so that there is no excess water drained off during processing.

[0018] A still further object and advantage of the present invention is to eliminate cooking of beans in excess water, thereby savings considerable added heat energy.

[0019] Yet another object and advantage is to minimize the addition of water prior to or during the cooking process, which reduces the energy requirements of heating the added water.

[0020] A still further object and advantage is to eliminate the high cost of chilling added water after cooking.

[0021] Additionally, it is an object of the invention to provide a cooking system that produces a hummus puree that is commercially sterile with zero measureable pathogens and live spores and maintains the commercially sterile condition throughout the downstream mixing and hydration process.

[0022] Yet another object and advantage is to provide a process that increases yield as a result of increased gelatinization and processing under pressure.

[0023] A further object and advantage of the inventive process is that it discharges into an aseptic packaging system a hummus product that is essentially free of any cells or spores that can grow during a 60-day refrigerated shelf storage period. This will allow the formulation of the final hummus product with a pH level above 4.2 with a natural flavor without adding a preservative. Brief Description of the Drawings

[0024] The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawing wherein:

[0025] FIG. 1 is a schematic view showing the inventive dry cooking and hydration process for pulses and seeds.

Best Mode for Carrying Out the Invention

[0026] The inventive pulse dry cooking and hydration system and process 10 includes and integrates four separate continuous processes into a single closed system. The first step in the process is dry friction cooking 12. The dry friction cooking system receives whole, dry chickpeas 14 from silo storage. Typically, the whole chickpeas have approximately 11% moisture as they come from the storage silos, where they are dried after field harvest. The dry raw product is placed in a feed hopper 16, which delivers the product to a pulsator dry friction cooker 18. Exemplary machines include the Pulsator P-300 or P-600 Model friction cookers by Koex Pty Ltd, Braeside, Victoria, Australia. The friction cooking process pulverizes the dry chickpeas without any water being added and heats the dry bean fragments to between 100 C to 200 C at pressure up to 40 bar (580 psi).

[0027] The cooked chickpeas are discharged from the friction cooker through an outlet 20, at which time they are in the form of dry granular flakes having approximately 4-6% moisture. The remainder of the natural moisture is flashed off as steam and then condensed back into the cooked chickpea flakes. The temperature of the discharged chickpea flakes flash cool down to 100 degrees C as they discharge from the friction cooker and enter the non-pressurized atmosphere of the closed chamber.

[0028] The second step in processing is hydration and mixing 22. The cooked dry chickpea flakes are pumped, transferred by gravity, or washed with hydration water through a closed, sealed transition 24 into a mixing and milling chamber (disintegration mill) 26, which has a hydration and mixing portion 36 with a rotating high speed mixer blade 29 inside, the mixer blade operatively connected to a high speed motor 28. An exemplary mixing and milling chamber system is the Corenco M8A angled disintegrator, made by Corenco, Inc., of Sebastopol, California. The hydration and mixing system is preferably performed in a closed, airtight system. However, as an alternative to using an airtight process, the system may be flushed with an inert gas during production. For instance, during transit through the sealed transition, inert gas from an inert gas source 30 may be introduced through a gas injection manifold 32 to impose aseptic processing conditions on the system. The gas may be injected into the sealed transition or into the disintegration mill. By injecting an inert gas into the disintegration mill any potential for pathogens or spores from the environment getting into the closed process is eliminated.

[0029] As product is transferred from the dry friction cooker through the sealed transition 24 into the disintegrator mill, clean, potable water, preferably though not necessarily chilled to approximately 4 degrees C, is pumped through pipes 34 into the hydrating and mixing portion 36 of the disintegrator mill using a metering pump 38. The water is combined with the cooked chickpea flakes in the proper ratios to create a chickpea puree. In the disintegrator mill, the chilled water contacting the 100 degree C cooked chickpea flakes rapidly cools the flakes. Using a ratio of chilled water to chickpea flakes of approximately 3: 1, the chickpea flakes and developing puree are flash cooled from 100 degrees C to approximately 8 degrees C. This rapid cooling condenses the steam that had earlier flashed off at the discharge of the dry friction cooker, thus contributing to the hydration of the chickpea flakes. This is a significant processing feature, because the portion of the original 11% moisture content in the raw chickpea beans that flashed off in the sealed transition (approximately 5-7% of the original moisture content) now condenses back into the chickpea puree, thus keeping the closed airtight system from over pressurizing.

[0030] Combining cold water with the hot chickpea flakes increases the moisture pickup of the friction cooked chickpea flakes, thereby increasing the yield of the chickpea puree. A whole chickpea soaked and cooked in the excess water process will have a moisture content of about 70% moisture, or 2.33 to 1 moisture, relative to dry matter. A chickpea dry friction cooked and hydrated in the inventive closed hydration system will end up with approximately 77% moisture, or 3.35 to 1 moisture ratio, a significant improvement in yield. [0031] The third processing step is milling 40. This step also includes further mixing of the product. This is accomplished as the chickpea flakes and chilled water shatter as they hit the blade 29 of the high speed mixer, which may be rotating at speeds up to 3000 rpm or higher. The disintegrator blade combines the water with the chickpea flakes and forces both through the circular milling screen, which divides the mixing and milling chamber into the hydration and mixing portion 36 discussed above, and a milling portion 41. The particle size of the hydrated chickpea puree is determined by the size of the holes in the screen, which are preferably from 150 micron to 2,000 microns in size. As the chilled water and chickpea flakes pass through the screen, the flakes are wetted and comminuted down to the size of the holes in the screen. The process of forcing the chickpea flakes through the screen with the water is a very effective method of mixing the cooked chickpeas with the hydration water, and this step eliminates 'fish eyes' forming from un-hydrated particles of chickpea.

[0032] The fourth processing step 42 is pressure boosting for added hydration. At the outlet 44 of the disintegrator/mixer is a positive displacement high pressure pump 46. This pump receives the hydrated and mixed hummus puree and pumps the puree downstream through a high pressure water absorption line 48 against a back pressure created by pumping against a back pressure control valve 50, which modulates the pressure in the closed system. In the alternative, a positive displacement back pressure pump (not shown) could be used in place of the back pressure valve. This section of the system between the high pressure pump and the back pressure control valve forms a chamber of backpressure on the chickpea puree flowing through. In this section of the process the puree is exposed to an increased pressure up to as high as 13 bar (188 psi) causing the puree to absorb an additional 1% to 3% water, increasing the yield of the puree even further. In addition, this boost in pressure on the puree also fixes the moisture in the chickpea puree so that it does not leach back out in the package during the 60-day refrigerated storage period. The pressure boost also allows the upstream water metering pump 38 to be set to add more water to the puree than would be absorbed into the puree if this boost of pressure were not applied to the puree. The added moisture would not be absorbed and the discharged chickpea puree would not have the additional yield or the desired viscosity.

[0033] After pressure boosted hydration, the chickpea puree is discharged for packaging 52 or further aseptic processing.

[0034] Improvements in yield and the reduction in production cost and production space are but a few of the advantages of the present invention. The inventive process is a completely closed, airtight process in which there is no human contact with the product from the time the whole chickpeas enter the friction cooker until the puree is discharged into the customer's aseptic packaging system. Because the friction cooker discharges commercially sterile, dry chickpea flakes and the downstream hydration process maintains the sterility therefore there is no point in the overall process that permits pathogens or spores from the environment to enter into the puree. Because of this closed, airtight process the sterility of the puree is maintained. Thus, it is possible to formulate the product with improved flavor with a pH of over 4.2 and without any need to add preservatives. If package integrity is maintained, the product will be considered 'all natural' and will have a refrigerated 60-day shelf life.

[0035] From the foregoing it will be appreciated that in its most essential aspect when viewed as a system, the present invention is a dry cooking and hydration system for dry pulses and seeds that includes a product input for supplying dry and uncooked product to said system; a dry friction cooking section system for receiving dry pulses or seeds from said product input and pulverizing and heating the dry product without adding water, and having a product discharge outlet; a sealed transition for transferring product discharged from said dry friction section to a second cooking section; a hydration and mixing section disposed within a sealed and airtight mixing and milling chamber having a hydration/mixing portion, a high speed mixer blade located in said hydration portion and operatively connected to a motor, and a chilled water supply in fluid communication with said hydration portion, wherein said hydration portion simultaneously receives product from said sealed transition and chilled water from said chilled water supply; and a milling section disposed within said mixing and milling chamber comprising a milling screen dividing said chamber into said hydration and mixing section and said milling section, wherein product is forced through said milling screen by said mixing blade during processing, said milling section having a product outlet.

[0036] When viewed in its most essential aspect as a process, the inventive system is seen to be a method of cooking and hydrating dry pulses and seeds, comprising the steps of feeding a volume of dry pulses or seeds into a dry friction cooker; friction cooking the product at a predetermined rate; transferring the cooked product into a hydration system through a sealed transition into an airtight mixing and milling chamber having a comminution screen and a rotating high speed mixer blade; pumping clean, potable, chilled water into the mixing and milling chamber and onto the mixer blade so as to rapidly cool the cooked product and to combine the cooked product with the water in a ratio necessary to produce the desired degree of hydration; and forcing the product and water through the comminution screen to limit the particle size of the hydrated product.

[0037] The inventive process has been described using an exemplary chickpea cooking and hydration process as a predicate to making hummus. However, numerous other dry pulse cooking and hydration processes are contemplated and encompassed within the foregoing description. For instance, gelatinized corn flour processed using the inventive process can be combined with raw corn flour in the right percentages to make a paste that can be formed in sheets for punching out corn tortillas. This new process eliminates the traditional method that entails soaking corn and cooking it in excess water, dramatically reducing the cost of production. In making tortillas with the inventive system can include the addition of lime to give the final product a special flavor that conventionally produced tortillas have when the corn is soaked in lime water.

[0038] In Japan most pastries use a base ingredient made from a white bean soaked in excess sugar water and then cooked in the excess sugar water. The sweetened beans are then ground into a sweet paste - on paste - which is used as the base ingredient. The inventive system can be used in a manner similar to that used in making hummus, but it would use a thick sugar water to hydrate the bean flour produced with the pulse dry cooking technique.

[0039] In Indonesia the staple breakfast food is a rice pudding, which is soaked and cooked with sugar water into a slurry of soft mashed rice kernels. The inventive system described herein can be used to make a pulse dry cooking product with rice and mixing in dry flavoring which would be sold as an instant breakfast rice pudding product.

[0040] And finally, corn for whiskey must be soaked and cooked in excess water and then fermented to make whiskey. By using the pulse dry cooking method disclosed herein to cook the corn, the whiskey making process can be dramatically streamlined.

[0041] The above description and illustrations should not be construed as limiting the scope of the invention, which is defined by the appended claims.

Claims

CLAIMS What is claimed as invention is:

1. A cooking and hydration system for whole seeds and pulses, comprising:

a dry friction cooker having a product inlet and a product outlet;

a hydration system in fluid communication with said product outlet of said dry friction cooker, wherein said hydration system is airtight or includes an inert gas supply so as to maintain commercial sterility of the product being processed;

means for transferring product from said dry friction cooker to said hydration system;

a disintegrator mill in fluid communication with said hydration system, said disintegrator mill including a comminution screen defining a comminution screen portion within said disintegrator mill, a motorized mixer operatively coupled to a mixer blade in said comminution screen portion, and an disintegrator mill outlet; and

a pressure boosting hydration system in fluid communication with said disintegrator mill outlet and in fluid communication with a back pressure control valve which modulates pressure in the system to produce a back pressure on product passing through said pressure booting hydration system.

2. A dry cooking and hydration system for dry pulses and seeds, comprising:

a product input for supplying dry and uncooked product to said system;

a dry friction cooking section system for receiving dry pulses or seeds from said product input and pulverizing and heating the dry product without adding water, and having a product discharge outlet;

a sealed transition for transferring product discharged from said dry friction section to a second cooking section;

a hydration and mixing section disposed within a sealed and airtight mixing and milling chamber having a hydration/mixing portion, a high speed mixer blade located in said hydration portion and operatively connected to a motor, and a chilled water supply in fluid communication with said hydration portion, wherein said hydration portion simultaneously receives product from said sealed transition and chilled water from said chilled water supply; and

a milling section disposed within said mixing and milling chamber comprising a milling screen dividing said chamber into said hydration and mixing section and said milling section, wherein product is forced through said milling screen by said mixing blade during processing, said milling section having a product outlet.

3. The system of claim 2, wherein said dry friction cooking section is a pulsator friction cooker.

4. The system of claim 2, wherein said dry friction cooking section heats dry product to between 100 C to 200 C at pressure up to 40 bar (580 psi).

5. The system of claim 2, wherein said dry friction cooking section produces a product output in the form of dry granular flakes having approximately 4-6% moisture when discharged.

6. The system of claim 2, further including a flash off portion where natural moisture remaining in the dry product flashes off as steam when discharged from said dry friction cooking section, and wherein steam from said flash off is contained within said system for use as a condensate to be added back into the product when cooked.

7. The system of claim 2, including means to flash cool product discharged from said dry cooking section to a temperature of approximately 100 degrees C.

8. The system of claim 2, where said mixing and milling chamber is an airtight chamber.

9. The system of claim 2, further including an inert gas supply in fluid communication with either or both of said mixing and milling chamber or said sealed transition for flushing said sealed transition or said chamber or both with an inert gas during production.

10. The system of claim 2, wherein said hydration and mixing section pumps clean, potable into said hydration and mixing portion of said mixing and milling chamber, wherein the water is combined with the cooked product ratios to create a product puree.

11. The system of claim 10, wherein said water is chilled to approximately 4 degrees

C.

12. The system of claim 2, wherein said mixing blade combines the water with the product and forces both through said milling screen, and wherein the particle size of the hydrated product is determined by the size of the holes in said milling screen.

13. The system of claim 12, wherein the holes in said milling screen are from 150 micron to 2,000 microns in diameter.

14. The system of claim 2, further including a pressure boosting section proximate said outlet of said mixing and milling chamber, including a displacement pump, a high pressure water absorption line, and a back pressure system having a back pressure valve, wherein said displacement pump receives hydrated and mixed product from said mixing and milling chamber and pumps the product downstream through said high pressure water absorption line against a back pressure modulated by said back pressure back pressure control valve.

15. The system of claim 14, wherein said pressure boosting section includes a positive displacement high pressure pump.

16. A method of cooking and hydrating dry pulses and seeds, comprising the steps of: feeding a volume of dry pulses or seeds into a dry friction cooker; friction cooking the product at a predetermined rate; transferring the cooked product into a hydration system through a sealed transition into an airtight mixing and milling chamber having a comminution screen and a rotating high speed mixer blade;

pumping clean, potable, chilled water into the mixing and milling chamber and onto the mixer blade so as to rapidly cool the cooked product and to combine the cooked product with the water in a ratio necessary to produce the desired degree of hydration; and forcing the product and water through the comminution screen to limit the particle size of the hydrated product.

17. The method of claim 16, further including the steps of:

transferring the milled and mixed product to a pressure boosted hydration system for added hydration; and

pumping the hydrated and mixed product against a back pressure modulated by a back pressure control valve.

18. The method of claim 16, further including the steps of:

pumping the hydrated and mixed product against a back pressure provided by a positive displacement pump.