Homogeneous fiber product based on bio-oil and/or water and method for their production

Abstract

The present invention relates to typically homogeneous gel-like cellulose-based fiber products which do not contain hemicellulose but may nevertheless contain lignin. The invention relates also to a method for the production of such fibrous products, in which microcrystalline cellulose (MCC) is mixed into oil or water to form a fiber mixture, and is degraded into homogeneous form by mechanical treatment.

Claims

1. A method for producing an oil- or water-based homogeneous fiber product from microcrystalline cellulose (MCC), wherein the MCC is mixed with oil or water, or a mixture thereof, into a fiber mixture and is degraded into homogeneous form by a two-stage mechanical treatment.

2. The method according to claim 1, wherein the MCC is either unbleached lignin- and cellulose-containing MCC, or bleached cellulose-containing MCC.

3. The method according to claim 1, wherein an oil-based fiber mixture including 0.5 to 20% by weight of water, preferably 1 to 10% by weight, is formed from the MCC.

4. The method according to claim 1, wherein the MCC is mixed into an oil-based fiber mixture having at least 1% water and at least 1% fiber in the oil, or preferably into an oil-based fiber mixture having at least 2% water in the oil.

5. The method according to claim 1, wherein the oil is selected from liquid oils or oils that become liquid when the temperature rises to temperatures of >20° C.

6. The method according to claim 1, wherein the consistency when feeding the oil- or water-based fiber mixture to mechanical treatment is 5 to 20% by weight, preferably 10 to 15% by weight, with respect to the fiber.

7. The method according to claim 1, wherein the MCC is mixed into a water-based fiber mixture having a feed consistency of 10%, or a maximum of 15%, when being fed to mechanical treatment.

8. The method according to claim 1, wherein the MCC is mixed into an oil-based fiber mixture having a feed consistency of 5 to 10% with respect to the fiber when being fed to mechanical treatment.

9. The method according to claim 1, wherein in the first step of the two-stage mechanical treatment, the liquid part of the fiber mixture is made to cavitate, whereby the structure of the fiber particle weakens, typically softens and partially separates into fibers.

10. The method according to claim 1, wherein in the second step of the two-stage mechanical treatment, the particles of the fiber particle that were structurally weakened and partially separated into fibers in the first step are mixed into a homogenous fiber product when the mixture is passed through a small gap by means of pressure.

11. The method according to claim 1, wherein a fiber product is produced in which the particle is predominantly of microsize.

12. An oil- or water-based homogeneous fiber product, wherein it has been produced from microcrystalline cellulose (MCC) by a method for producing an oil- or water-based homogeneous fiber product from microcrystalline cellulose (MCC), wherein the MCC is mixed with oil or water, or a mixture thereof, into a fiber mixture and is degraded into homogeneous form by a two-stage mechanical treatment.

13. The oil- or water-based homogeneous fiber product according to claim 12, wherein it is MCC-based and contains either unbleached lignin- and cellulose-containing MCC or bleached cellulose-containing MCC.

14. Use of the oil-based homogeneous fiber product produced according to claim 1 in fat- and oil-based foods.

15. The use according to claim 14 in mayonnaises, chocolates or salad dressings, or in plastics by adding hydrophilic fibers.

16. Use of the water-based homogeneous fiber product produced according to claim 1 in foods such as mustards, ketchups, yoghurts, juices and sports drinks.

17. The method according to claim 5, wherein the oil is selected from oils of vegetable or animal origin, or fossil oils.

18. The method of claim 5, wherein the oil is selected from edible oils.

19. The method of claim 5, wherein the oil is selected from; linseed oil, mustard oil, almond oil, soybean oil, hemp oil, palm oil, peanut oil, castor oil, coconut oil or corn oil.

20. The method of claim 5, wherein the oil is selected from rapeseed oil, canola oil, sunflower oil, olive oil, or cocoa butter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1. An example of the operating principle of the two-stage device, whereby both water- and oil-based gels are obtained from an undried AaltoCell™ fiber product.

[0022] FIG. 2. Shown on the left side is a water-based gel-like cellulose fiber mixture with a feed consistency/final product consistency of 10%, and on the right side a pulp/lignin-based gel-like mixture with a feed consistency/final product consistency of 10%.

[0023] FIG. 3. Oil-based gel-like cellulose fiber mixture with a feed consistency of 8%.

[0024] FIG. 4. Shown in the middle of the figure is an aqueous gel-like mixture prepared with a feed consistency of 10% and diluted with water to a consistency of 1.5%. As shown in the figure, MCC without mechanical treatment is on the left and MCC with mechanical treatment with a feed consistency of 15% on the right.

DEFINITIONS

[0025] In the present context, the term “homogeneous fiber product” comprises a mixture or hydrocolloid having a partially hydrophobic or hydrophilic gel form.

[0026] “MCC”, i.e. microcrystalline cellulose, comprises particulate (microcrystalline) cellulose produced from fibrous cellulose by chemical degradation, from which hemicellulose has been removed at the same time. It can be either unbleached or bleached.

[0027] In the present context, “mechanical treatment” thus refers to a first pressurized treatment step of the MCC-containing mixture, by which cavitation is achieved, resulting in deterioration of the particle structure and possibly partial defiberization, and a second treatment step, in which the mixture is passed by applying pressure through a small gap in the treatment apparatus, whereby the weakened portion of the mixture can be further treated in order to mix the particles of the mixture into a homogeneous fibrous product.

[0028] “Cavitation” in turn, refers to the modification of fibers by the flow of the mixture (and the bubbles created by it), typically by weakening the fiber structure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The present invention relates to a method for preparing an oil- or water-based homogeneous fiber product from microcrystalline cellulose (MCC). In this method, the MCC is mixed with oil or water, or a mixture thereof, into a fiber mixture, and can be degraded to a homogeneous form by a two-stage mechanical treatment.

[0030] A typical liquid in the fiber mixture is water or oil, in which latter case there is also some water in the fiber.

[0031] The MCC is typically either unbleached, in which case it contains both lignin and cellulose, or bleached, being only cellulosic. Preferably it is unbleached, in which case it is lignin-containing microcrystalline cellulose.

[0032] The MCC can also be either dried or undried. Preferably, however, the MCC is undried, which facilitates obtaining a homogeneous, gel-like mixture.

[0033] Prior to mechanical treatment, the MCC is converted into a fiber mixture by mixing the MCC with oil or water.

[0034] However, if an oil-based mixture is used, the mixture typically contains 0.5 to 20% by weight, preferably 1 to 10% by weight, of water. Preferably, the oil-based mixture contains at least 1% water and 1% fiber. Typically, all concentrations are expressed as weight percents.

[0035] The oil is selected from liquid oils or oils that become liquid when the temperature rises to temperatures >20° C. Preferably, an oil of vegetable or animal origin, or a fossil oil is selected. Most suitably, however, the oil is selected from edible oils such as linseed oil, mustard oil, almond oil, soybean oil, hemp oil, palm oil, peanut oil, castor oil, coconut oil or corn oil, typically from vegetable oils such as rapeseed oil, canola oil, sunflower oil, olive oil, or cocoa butter.

[0036] A special feature of the method of the invention is that higher consistencies than before can be used when feeding the oil or water-based fiber mixture to mechanical treatment. Preferably, this feed consistency is 5 to 20% by weight, more preferably 10 to 15% by weight, based on the fiber.

[0037] In order to make the mechanical treatment as efficient as possible, a two-stage mechanical treatment is used.

[0038] According to an embodiment of the invention, in the first step of the two-stage mechanical treatment, a treatment is performed in which the liquid portion of the fiber mixture is made to cavitate, whereby the structure of the fiber particle changes, typically softens.

[0039] According to a second embodiment of the invention, in the second step of the two-stage mechanical treatment, the portion of the fiber particle that was structurally altered in the first step is caused to separate into fibers when the mixture is passed through a small gap by means of pressure.

[0040] In one exemplary embodiment, an oil-based gel-like cellulosic fiber mixture was prepared in the tests as follows: undried AaltoCell™ fiber blend in which AaltoCell pulp with a moisture content of 50% was mixed with rapeseed oil so that the mixtures contained 2, 4, 6 and 8% of both fiber and water. When passing such mixtures through the apparatus of FIG. 1 it was found that the fiber product is degraded as it would in the aqueous phase, but makes a homogeneous mixture with the oil. This phenomenon has not been previously observed or publicly reported.

[0041] As shown in FIG. 1, such a device may typically have a filter module, a nozzle module, a turbulence module, and a valve module.

[0042] A water-based gel-like cellulosic fiber mixture was prepared in a similar way, but without oil, achieving a maximum feed consistency of 15%, but most preferably 10%.

[0043] In the past, MCC or MFC dried by different methods has been merely mixed with oil, the problem being an inhomogeneous mixture in which the fibers have formed lumps in the oil. The mixture obtained by the method described above is homogeneous and forms with the fiber an oil mixture in which the oil does not separate from the fiber, whereby it is possible to speak of an oil-based gel-like cellulose fiber mixture produced in a new manner.

[0044] Water-based cellulose gel has also been prepared in the past, but a MFC gel obtained with a low feed density and still in the above-mentioned manner contains nano-sized particles, which are not produced by our method, all particles instead being micro-sized, at least substantially.

[0045] Shown in FIG. 4 is a water-based gel-like mixture prepared at 10% feed consistency by the previously described mechanical method and diluted to 1.5% consistency. This yielded a hydrocolloid which was evenly distributed in the aqueous solution and did not settle even over 66 h.

[0046] The present invention also relates to a product prepared by the described method. Because MCC is used as a source of cellulose in the method of the present invention, a product can be produced in which no significant amounts of nano-sized particles are present. The health effects of this kind of product have been investigated, whereby the fiber product according to the invention meets the requirements of the food and pharmaceutical industry.

[0047] Thus, the product according to the invention can be used in foodstuffs, and accordingly also in pharmaceutical additives.

[0048] Preferably, the oil-based AaltoCell™-based gel-like mixture prepared by the method described above can be used in fat- and oil-based foods to improve e.g. mouthfeel, such as in mayonnaise, chocolate, and salad dressings. In addition, it can be used in plastics to which hydrophilic fibers are added. In this case, the adhesion of the hydrophilic fiber in plastic products can be improved, whereby the strength properties of the composite are significantly improved and its production is facilitated when the oil reduces friction e.g. in extruder-type mixers.

[0049] The water-based AaltoCell™-based gel-like mixture prepared by the method described above can in turn be advantageously used in foods to improve the mouthfeel of the final product, such as in mustards, ketchups, yoghurts, juices and sports drinks.

The Embodiments

[0050] Embodiment 1. A mechanical method for producing water- and oil-based high-consistency gel-like cellulose fiber mixtures in which the particle size is predominantly of microsize and the mixture contains hardly any nano-sized particles.

[0051] Embodiment 2. A mechanical method for producing water- and oil-based high-consistency gel-like cellulose fiber mixtures in which the particle size is of microsize and the mixture contains no nano-sized particles.

[0052] Embodiment 3. The mechanical method typically requires two stages, in which in the first step the liquid portion of the fiber mixture, which is aqueous, is made to cavitate, whereby the fiber particle softens and can partially separate into fibers. In the second step, the defiberization of the softened portion of the fiber particle can be completed.

[0053] Embodiment 4. A mechanical method wherein an oil-based gel-like mixture is obtained when the oil-based mixture also contains water, enabling that cavitation step, and also the oil is made to distribute evenly in the gel-like mixture. Preferably, there is at least 2% water in the oil-based mixture, and more preferably 8%.

[0054] Embodiment 5. A mechanical method wherein prior to mechanical treatment, a fiber mixture is formed in which MCC is added to a water- or oil-based liquid to a consistency of 5 to 20% by weight based on the fiber.