Field of the invention

The present invention relates to a dietary fibre of tapioca origin and to a food product comprising a dietary fibre of tapioca origin. Background of the invention

Tapioca, also known as cassava and manioc, has been widely consumed as a human food for thousands of years. The name tapioca refers to the processed products of the roots of the tapioca plant. Millions of people around the world consume tapioca products on a regular basis. A variety of products containing tapioca have become popular and preferred due to their exceptionally bland flavour and unique textural attributes.

A number of dietary fibres are available on the market as ingredients for use in formulating food products. An example is potato fibre, which is received by grinding potatoes. The potato fibre has a large water binding capacity, which may result in that a food product comprising potato fibre is considered dry and woody. The addition of potato fibre to a food product can also result in giving the food product an unwanted residual flavour.

US patent 5,350,593 (LaCourse et al.) discloses a dietary fibre of tapioca origin, comprising on a dry solid basis, at least 70% total dietary fibre, of which at least 12% is soluble dietary fibre, and less than 15% starch, wherein the dietary fibre is said to have a water-holding capacity of at least 2.5 and a viscosity of at least 100 B. U. in a 5% aqueous solution. The dietary fibre according to US patent 5,350,593 is produced by means of a process comprising enzymatic treatment of a slurry of ground tapioca pulp (5 to 10% by weight in an aqueous media) with a 1 ,4-alpha-D-glucosidase to depolyme- rise sufficient starch to yield a tapioca fibre containing less than 15% starch. Thereafter the tapioca fibre is separated from the slurry and finally the tapioca fibre is washed to give a refined tapioca fibre.

There are some drawbacks with the dietary fibre according to US patent 5,350,593. For instance, the dietary fibre according to US patent

5,350,593 is not effective to use in some food applications. This drawback is related to the composition and possible structure of the dietary fibre of tapioca origin according to US patent 5,350,593. However, this drawback is in itself related to the object of US patent 5,350,593 and the process described therein. The process for the production of the dietary fibre according to US patent 5,350,593 comprises a starch depolymerisation step where 1 ,4-alpha-D- glucosidase is added to achieve an enzymatic treatment. By this enzymatic treatment, the starch is decomposed so that a cleaner fibre is possible to obtain after a washing step. In other words, the process according to US patent 5,350,593 is not natural as it involves adding chemical agents, such as 1 ,4-alpha-D-glucosidase but also a bleaching agent, e.g. hydrogen peroxide or sodium chlorite. Moreover, the process treatment used according to US patent 5,350,593 is not gentle for the fibre structure and contained starch. However, the purpose of the process according to US patent 5,350,593 is to obtain a very clean dietary tapioca fibre, and not to provide an optimal fibre for specific food applications. Summary of the invention

The aim of the present invention is therefore to solve the problems according to above regarding e.g. residual flavour and dry, woody food products when using dietary fibres in food products. Moreover, one other object of the present invention is to provide a dietary fibre of tapioca origin, which has optimal properties for some specific food applications, such as in meat applications. Moreover, the present invention is directed to provide a dietary fibre of tapioca origin having optimal fibre structure and composition, and which is possible to achieve by a totally natural process, i.e. without adding any chemical substances besides clean water. This is achieved according to the present invention by a dietary fibre having the characteristics as stated in claim 1. Preferred embodiments of the dietary fibre are given in the dependent claims 2-8.

The problem is further solved by a food product according to claim 9. Preferred embodiments of the food product are given in the dependent claims 10-14. Brief description of the drawings

Fig. 1 is a figure showing the good freeze/thaw stability of a dietary fibre according to the present invention compared to sugar beet fibre and wheat fibre. Definitions

The following terms and expressions are defined with a view to facilitate the understanding of the present invention. Meat

Throughout the present application the expression meat comprises skeleton muscles, MDM and organ raw materials, including offal, from all kinds of mammal, poultry, fish and mollusc. Fresh meat

Meat without any additives, which only has been cooled or deep- frozen, is called fresh meat. Meat products

Meat which has been cured so much that the appearance of the fresh meat has changed is called a meat product. Processed meat

Meat which has been cured with modern injecting methods that do not change the appearance of the meat is called processed meat. Heat treated meat products, whole or in pieces

An example is meat that has been cured so much that the appearance of fresh meat has changed and thereafter is heat treated. Heat treated meat products, small pieces An example is a meat product that has been produced by blending or emulsifying and thereafter is heat treated. Non heat treated meat products, whole or in pieces

An example is meat that has been cured so much that the appearance of fresh meat has changed, but the meat product is not heat treated. Non heat treated meat products, small pieces

An example is a meat product that has been produced by blending or emulsifying, but the meat product is not heat treated. Detailed description of preferred embodiments of the invention

When producing starch from tapioca, this leads to a lot of waste material normally used as feed, which by the present invention can be used for the production of a dietary fibre instead. This gives a great advantage and opportunity for the factories producing starch from tapioca, since the waste material now can be used for dietary production, creating both better economy to the production and job opportunities.

A new natural dietary fibre derived from tapioca roots has been found to offer significant advantages compared to other commercial fibre sources in food products. This dietary fibre of tapioca origin comprises 35-60% by weight total dietary fibre and 30-50% by weight starch, on a dry solids basis.

In a preferred embodiment of the present invention the dietary fibre comprises 46-53% by weight total dietary fibre and 35-40% by weight starch, on a dry solids basis.

In a further preferred embodiment of the present invention the dietary fibre comprises 49% by weight total dietary fibre and 37% by weight starch, on a dry solids basis.

In another preferred embodiment the fibre distribution, when the total dietary fibre is 46-53% by weight, the fibre distribution is 38-45% by weight insoluble fibres and 6-10% by weight soluble fibres, on a dry solids basis.

In one preferred embodiment the fibre distribution, when the total dietary fibre is 49% by weight, the fibre distribution is 41 % by weight insoluble fibres and 8% by weight soluble fibres, on a dry solids basis. There are several advantages of the dietary fibre composition of tapioca origin according to the present invention in comparison to known tapioca fibre compositions. One such advantage is the high content of starch giving a high water binding (holding) capacity. However, a high content of starch as such does not provide this property without the right structure of the dietary fibre. According to the present invention, the starch granules are contained inside of the intact fibre matrix structure, also after the mechanical treatment, which provides this property. This structure, where the starch granules are contained inside of the cell wall matrix of the fibre in granular shape, provides a natural fibre which absorbs water and fat at desired temperatures in a controlled way. This is due to a protection of the starch granules which as such may swell up in a controlled way when exposed to water. As said, the fibre according to the present invention, having a high content of intact fibre and enclosed starch granules, has enhanced properties. When compared to only fibre content, this does not have a high water holding capacity, and when compared to only starch, this swells up and retrogrades faster when exposed to heat or shear. The fibre matrix structure according to the present invention, however, provides a controlled water holding capacity at increased tempera- tures.

These properties are not something achieved by known dietary tapioca fibre compositions today. For example, the fibre according to US patent 5,350,593, having a low content of starch, does not have a similar water holding capacity when compared to the fibre according to the present inven- tion. Due to the fact that the starch content is low and not enclosed inside of an intact fibre structure, such as according to the present invention, the water holding capacity will not increase when heated in such an effective way as for the fibre according to the present invention. Although the water holding capacity is similar at room temperatures for the two different fibres, the value of the water holding capacity at increased temperatures is much better for a dietary fibre according to the present invention in comparison with the fibre composition of US patent 5,350,593. This is explained in more detail below and especially with reference to Fig. 2.

Chemical analysis of examples of dietary fibres according to the pre- sent invention gave the following composition: Chemical analysis of dietary fibres

The composition of the dietary fibre, with a high content of both fibre and starch, makes it special. When viewing the fibre particles in a microscope you will find the starch granules both enclosed in the fibre matrix and as free granules between the fibre structures. Therefore, according to one embodi- ment of the present invention, the starch content is provided as starch granules which are both enclosed in the fibre matrix and as free granules between the fibre structures. When heating the fibre, this composition will increase the water holding capacity, resulting in a pulpy texture with a smooth appearance.

The dietary fibre further has a very good freeze/thaw stability compa- red to several other known fibres. After three cycles of freeze/thawing the dietary fibre according to the present invention hold the water almost twice as good as fibre from sugar beet or wheat, which is shown in Fig. 1.

Now with reference to Fig. 2, this figure shows that the water holding capacity (WHC) for the dietary fibre according to the present invention increa- ses with increasing temperatures. The actual test is performed according to the following. 5% of fibre according to the present invention is mixed with 95% water. The desired temperature is set in a water bath and then the sample is stirred at low speed. After that the sample is allowed to cool to about 24 ^Q C, the sample is thoroughly stirred and then centrifuged 6 min at 4000 rpm. Finally, the water phase is removed and the content of water held by the fibre is measured.

The increase in WHC is also something obtained for starch alone with an increased temperature, however the fibre according to the present invention maintains the WHC on a high level at higher temperatures and does not release the water again, which happens for a starch alone as it retrogrades. It is important to understand that the fibre content of the dietary fibre according to the present invention, in addition to the starch granules, of course also binds the water. This high WHC level at high temperatures is not possible to obtain for known dietary tapioca fibre compositions, such as the one disclo- sed in US patent 5,350,593. Due to the properties of the dietary fibre according to the present invention, it is very effective to use in different food applications, such as in processed meat products, e.g. heat treated meat products. A further attractive feature of the dietary fibre according to the present invention is that it only contains very low levels of fat. The absence of fat leads to the avoidance of undesirable problems associated with rancidity and residual flavour development, and appeals to health-conscious consumers who want to decrease their consumption of fat.

The dietary fibre has, however, due to the special ratio between starch and fibre, a high water/fat holding capacity, which results in that more water and/or fat stays in a food product comprising the dietary fibre. The result of this is increased juiciness, improved yield and reduced cooking losses. A suitable dosing of the dietary fibre in meat products is 0.5 to 3.0% by weight.

In Asia carragenan is traditionally used to obstruct the water loss in different types of meat products. The dietary fibre according to the present invention has a dual functionality in these applications, binding water and fat very effective in the emulsified products and also preventing leakage of water and fat to the surface.

In a traditional chicken sausage normally both modified tapioca starch and carragenan is added to achieve the right texture and to avoid water loss during heating. When using the dietary fibre of tapioca origin according to the present invention a better water holding capacity is reached, while it is possible to decrease the level of starch. When using the dietary fibre according to the invention the cost is also decreased noticeably.

Isolated Soy Protein, ISP, is often used in emulsion products for emulsifying the fat in the product. If the ISP is replaced 1 :1 with the dietary fibre according to the present invention a much better flavour release and a cleaner taste without affecting the texture is achieved. A change also results in a lower cost.

To compensate for the water loss during preparation and to restore the original water content in meat products it is very common to inject some type of brine into the meat. Some type of phosphate and brine are often used. To reach an even better water binding capacity, giving a juicier meat with reduced cooking loss, a dietary fibre according to the present invention can be used. An example of meat to be treated with the dietary fibre according to the present invention is chicken. Other examples are pork, lamb, beef and fish. The dietary fibre can be used in both meat products and processed meat. The addition of 0.5-3.0% by weight of the dietary fibre according to the invention in brine to meat gives a yield of 90-95% with a very good texture. When adding the dietary fibre to brine when tumbling meat it is possible to reach a yield of 95-99% depending on the dosage. The texture is influenced in a positive way, giving a better feeling of whole meat.

The dietary fibre according to the present invention also has the advantage that it binds less water than e.g. potato, is more colour neutral and gives less residual flavour. In view of this, a larger amount of the dietary fibre according to the invention can be added to a food product in comparison to potato fibre.

The dietary fibre according to the invention also works well in traditional fibre applications, such as in baked goods, extruded products, breakfast cereals, fruit fillings etc. and is an excellent alternative to improve the texture.

The dietary fibre according to the present invention can be manufactured in different particle sizes. The particles with the larger size, i.e. with a particle size of 200 μm or more, are called T-fibre and work excellent in emulsion products and traditional fibre applications. The particles with the smaller size, i.e. with a particle size of less than 200 μm, are called T-crown, give no visible parts in an otherwise homogenous product, which makes them suitable for tumbling and injection. Otherwise, the smaller particles have all the properties and advantages as the larger particles.

In one embodiment of the present invention the dietary fibre has a par- tide size of less than 500 μm.

In a preferred embodiment the dietary fibre has a particle size of less than 200 μm.

In a further preferred embodiment the dietary fibre has a particle size of less than 100 μm. HCN is an important parameter in all tapioca products. A chemical analysis of the dietary fibre according to the present invention gave a content of 4.0 mg HCN/kg fibre, which means that if a person at 70 kg eats 50 g/day of the tapioca fibre according to the present invention then that person consu- mes 0.20 mg HCN. This corresponds to 2.9 μg HCN/kg body weight, i.e. a very low consumption of HCN. Reported lethal dose for a human being at acute toxicity is somewhere between 0.5-3.5 mg HCN/kg body weight. Process for production of the tapioca fibre The tapioca fibre according to the present invention can be produced according to the following process:

The tapioca roots are controlled at the production line, and any occurring waste material, such as stones etc, are removed. Thereafter, the roots are washed and are cut up into smaller pieces through rasping. After being cut up the incoming stream of tapioca is divided into three fractions, namely the starch fraction, the fibre pulp fraction comprising cell membranes, dry substance approximately 15%, and the remaining wet fraction.

The pulp fraction is then transported to the tapioca fibre process and the fibre is filtrated to remove any large impurities. Remnants of soil and sand, if any, are removed to ensure a clean fibre. The clean fibre phase is refined and thereafter dewatered mechanically to achieve a drying step with as low addition of energy as possible. The fibre is then dried to a water content of 8-10% by weight. After drying the fibre is processed into a specified particle size. The process for producing the tapioca fibre according to the present invention is a physical and thermal process where the only addition is clean water at the washing step. No foreign chemical agents are added.