The present invention relates to a puff pastry that is based on potato. The invention further relates to a dry mix for preparing puff pastry dough, to food products prepared from the puff pastry and to a method for preparing the food products.

Puff pastry is a flaky light pastry made from a laminated dough composed of dough and butter or other solid fat. The butter is put inside the dough (or vice versa), making a dough ball which is repeatedly folded and rolled out before baking. The gaps that form between the layers left by the fat melting are pushed (leavened) by the water turning into steam during the baking process.

Most doughs and also the dough used for making puff pastry have viscoelastic properties. This is often the result of gluten which gives elasticity to dough, helping it rise and keep its shape and often gives the final product a chewy texture. Gluten comprise proteins, such as prolamins and glutelins, that are stored together with starch in the endosperm of various grass- related grains. It is found in wheat, barley, rye, oat, related species and hybrids, such as spelt.

A small part of the general population is hypersensitive to gluten, which can trigger coeliac disease and other gluten-related disorders. These people cannot eat food products prepared from gluten-containing doughs and batters. It is therefore desirable to have alternatives that have the same or similar mouth-feel and the same cooking characteristics.

It is therefore an object of the present invention to provide an alternative type of puff pastry that can be used for the preparation of food products that are also suitable for use in a gluten-free diet.

In the research that led to the present invention it was found that it is possible to prepare a versatile puff pastry based on potato that can be mechanically processed and is extendable. Potato is gluten-free and can thus be part of the diet of gluten-intolerant people.

The present invention thus relates to a dry mix for the preparation of a potato-based puff pastry dough, comprising dehydrated potato, added starch, added protein and optionally added amylopectin and added sugar. The added starch, protein, amylopectin and sugar are added to the mix in addition to starch, protein, amylopectin and sugar originating from the dehydrated potato. The extra starch, protein, amylopectin and sugar that are added to the mix are added as such. The composition of the above ingredients are called herein“dry mix”. When this dry mix is mixed with a liquid a so-called“pre -dough” is formed. When a fat is added to the pre-dough and the fat is laminated by rolling and turning a number of times a“puff pastry” is obtained. The puff pastry is the starting material for various types of food products. A dry mix has a much longer shelf-life than wet preparations. The puff pastry pre dough obtained after adding a liquid to the dry mix can be turned into an actual puff pastry by adding a fat, such as butter, and repeatedly rolling out and folding the dough to obtain layers.

Dehydrated potato is prepared according to well-known processes. In summary, raw potato pieces are steam cooked, mashed, dried and comminuted into flakes or granules. Both forms can be used in the dry mix of the invention. Dehydrated potato flakes or granules thus comprise all the ingredients already present in the raw potato and optionally in addition a processing aid, such as an emulsifier. Freshly harvested, potato contains about 80 percent water and about 20 percent dry matter. About 60 to 80 percent of the dry matter is starch. In addition, the potato contains protein and is low in fat. Potatoes are rich in several micronutrients, especially vitamin C. They also contain iron, vitamins Bl, B3 and B6 and minerals such as potassium, phosphorus and magnesium, and contains folate, pantothenic acid and riboflavin. Potatoes also contain dietary antioxidants. The dehydrated potato used in the present invention is suitably made from raw potato and contains all its constituents. Suitably, the dehydrated potato constitutes more than 50% of the dry mix. This means that when combining the various ingredients of the mix 50% thereof is formed by dehydrated potato.

Suitably, the potato flakes for use in the dry mix of the invention have the following composition: 75-80% starch, consisting of 20-30% amylose and 70-80% amylopectin, 8-10% water, 6-10% protein, 1-3% sugar and 0.1-1% fat.

Dehydrated potato can be prepared from different potato varieties that have differing contents of the components. The average nutritional value of fresh raw potato is however considered to comprise: 77% water, 18% starch of which 20-30% is amylose and 70-80% is amylopectin, 2% protein, 1% sugar and 0.1% fat. After processing fresh potatoes to dehydrated potato flakes the composition of the potato flakes is about 78% starch, about 9% water, about 8% protein, about 1% sugar and about 0.5% fat.

In a preferred embodiment the potato content of the dehydrated potato is at least 95%. In an even more preferred embodiment the dehydrated potato is made from fresh potato. The advantage there of is that it still comprises an amount of native starch. The combination of native and heat treated starch in the potato flakes contributes to the viscosity and elasticity of the puff pastry dough. In addition, it provides the puff pastry with a good moisture balance.

The dry mix of the invention further comprises a starch. The starch is added to the mix in addition to the starch that originates from the dehydrated potato. In a preferred embodiment, the added starch is at least partially, preferably completely formed by potato starch. The added starch can either be native starch or modified starch or combinations thereof.

As a further ingredient the dry mix comprises an added protein. The protein is added to the mix in addition to the protein that originates from the dehydrated potato. Preferably the added protein is a potato protein, in particular a native potato protein. Native potato proteins can be divided into the following three classes: (i) the patatin family, highly homologous acidic 43 kDa glycoproteins (40-50 wt. % of the potato proteins), (ii) basic 5-25 kDa protease inhibitors (30-40 wt. % of the potato proteins) and (iii) other proteins, mostly high molecular weight (HMW) proteins (10-20 wt. % of the potato proteins). HMW proteins are proteins with a molecular weight of >200 kDa.

The protein that is added to the mix has preferably not been heat-treated and is thus not inactivated. This is different from the protein present in the dehydrated potato flakes or granules. These proteins underwent a heat treatment during production of the flakes. The added protein is thus preferably a native protein with functionality in dough and baking properties.

The added native potato proteins are mainly formed by patatin, protease inhibitors and HMW proteins. These proteins are in particular useful in the dry mix of the invention and are thus a preferred ingredient. It is found that the addition of potato proteins provides the puff pastry pre dough and the puff pastry of the invention with the ability to be mechanically processed, makes it extendable and contributes to the viscoelastic properties of the puff pastry pre-dough and puff pastry of the invention.

The dry mix of the invention also comprises amylopectin. The amylopectin is added to the mix in addition to the amylopectin that originates from the dehydrated potato. The source of added amylopectin is preferably an amylopectin-rich potato starch. An amylopectin-rich potato starch comprises more than 70%, preferably at least 85%, more preferably 100% amylopectin. When a certain percentage of amylopectin is added to the mix this percentage is based on the actual amylopectin. When the amylopectin source is an amylopectin-rich starch that comprises less than 100% amylopectin a higher amount of starch is added to obtain the desired percentage of added amylopectin. The amylopectin is involved in the moisture control of the puff pastry dough. Amylopectin-rich starch can be obtained from potatoes that are genetically modified to produce a higher content of amylopectin, or potatoes that have a spontaneous or induced mutation that leads to higher content of amylopectin or the amylose may be removed from the starch leaving a higher amylopectin content.

The dry mix of the invention preferably also comprises an added sugar but this ingredient is optional. The sugar is added to the mix in addition to the sugar that originates from the dehydrated potato. Suitably, the sugar is dextrose monohydrate, and preferably it is potato dextrose monohydrate. Alternatively, the dextrose originates from a source other than potato, such as corn or rice. The sugar is added for obtaining a nice golden-brown color after baking or frying and confers crispiness to the end product.

In addition to the above ingredients, the dry mix may further comprise one or more additional ingredients selected from salt, flavorings, coloring agents, seasoning, spices, eggs, yeast. The dry mix of the present invention preferably comprises at least 90%, preferably 92%, more preferably 95% potato ingredients. This will for example be the case when the mix also contains salt which is inherently not potato-based and dextrose from another source, such as corn or rice. Even more preferably, at least 98% of the ingredients originate from potato. This will for example be the case when the mix also contains salt which is inherently not potato-based. Most preferably, the dry mix is completely potato-based. The advantage of an almost completely potato- based product is that it will not contain traces of gluten. Furthermore, the fried or baked product will be crispy on the outside and soft, like puree, on the inside leading to an attractive mouth-feel.

In one embodiment the dry mix of the invention comprises:

40-70%, in particular 50-60% dehydrated potato;

15-40%, in particular 20-35% added starch;

3-12%, in particular 5-10% added protein;

1-10%, in particular 2-6% added amylopectin;

optionally 1-5%, in particular 2-4% added sugar; and

optionally 0.5-3.5%, in particular 1-3% salt.

In one particular embodiment, the dry mix comprises:

about 57% dehydrated potato;

about 28% potato added starch;

about 7% potato added protein;

about 3% added amylopectin-rich potato starch;

about 3% monohydrate potato dextrose; and

about 2% salt.

The above composition of the dry mix of the invention lists the separate components that are blended to make up the dry mix. It is in fact the recipe for preparing the dry mix. However, dehydrated potato also comprises starch, protein, amylopectin and sugar. After mixing the above listed ingredients the composition has a content of the components starch, protein, amylopectin and sugar that is different from the added amounts listed above. The composition of the mix after blending the ingredients thus comprises:

60-80%, in particular 65-75% starch, comprising, in particular consisting of 15-30%, in particular 17-27% amylose and 70-85%, in particular 73-83% amylopectin;

5-15%, in particular 10-13% protein;

optionally 1-5%, in particular 2-4% sugar;

0.1-1%, in particular 0.3-0.7% dehydrated potato components other than starch, protein, amylopectin and sugar, in particular fat;

optionally 0.5-3.5%, in particular 1-3% salt.

In one embodiment, the dry mix consists of the above listed components, in particular: about 70% starch, which comprises, and in particular consists of 17-27% amylose and 73-83% amylopectin;

about 11% protein;

about 3% sugar; and

about 0.5% fat.

According to a further aspect thereof the invention relates to puff pastry pre-doughs prepared from the dry mix. The puff pastry pre -dough is produced by mixing the dry mix with a liquid.

Optionally, further ingredients can be added to the pre-dough. One additional ingredient is coconut oil. The pre -dough suitably comprises 0-10%, in particular 2-5% coconut oil, more in particular about 3% coconut oil. Depending on the temperature coconut oil is either liquid or solid. Another useful ingredient is glutinous rice, which can be added in an amount of 5-15%, in particular 8-12%, more in particular about 10%. Glutinous rice provides the dough improved extensibility, better recovery after rolling and better sheetablility. Furthermore, 0.1-2%, in particular 0.5-1.5% HPMC (hydroxypropyl methylcellulose) can be added to the pre-dough. This ingredient also improves the recovery and sheetablility and further enhances resistance to extension and facilitates film forming.

The liquid used in the puff pastry pre -dough can be any liquid but is preferably selected from water, oil, fat, in particular baking fat, butter, egg or combinations thereof. The various liquids can confer different characteristics to the end product. The term“liquid” as used herein thus also refers to solids that can be liquefied, such as fats and butter, or to semi-solids, such as eggs.

The puff pastry is prepared from the pre-dough by the addition of a fat. Common types of fat used include butter, vegetable shortenings, margarine, zero trans & low trans-fat types and lard. Butter is most commonly used because it provides a richer taste and superior mouthfeel. Shortenings and lard have a higher melting point therefore puff pastry made with either will rise more than pastry made with butter. Low trans-fat types are fats that comprise less than 1.5g trans- unsaturated fatty acids per lOOg end product.

According to a further aspect thereof, the invention relates to a puff pastry pre-dough, comprising the dry mix and a liquid, wherein for 100% dry mix 80-120%, in particular 100% liquid is added.

The invention further relates to puff pastry, comprising a puff pastry pre -dough and a laminating fat folded into the puff pastry pre -dough. The laminating fat is suitably selected from butter, margarine, zero trans & low trans-fat types, etc.

Puff pastry can be processed in various ways, such as by kneading, rolling and shaping. Puff pastry according to the invention are suitable for the production of all products for which normal puff pastry is used, such as palmiers, fruit turnovers, apple beignets, sausage rolls, savory sticks, cheese rolls, pie’s pasties, tompouces, coffee buns, croissants, mille-feuille’s.

According to the further aspect thereof, the invention relates to food products prepared from the puff pastry described above.

The food products can have a sweet or savory taste depending on the additional ingredients that are added to the dry mix or to the puff pastry. Food products may themselves be filled with sweet or savory fillings, such as apple, raisins, cane sugar, pecan nuts, almond paste, cheese, custard pudding.

The food products are in general crispy and comprise multiple layers. Products made from naturel puff pastry have a potato taste. In other products the taste can be adapted by the addition of sweet and savory additives. The product can be colored with natural food colors, such as saffron water, tomato juice, beet juice, carrot juice etc.

According to the invention various commercial forms can be envisaged. One suitable commercial product is the dry mix which has a long shelf-life and can according to ones need be combined with a desired liquid and other ingredients. Other products made with the dry mix, such as the prepared puff pastry and semi-finished and finished products are also part of this invention. The puff pastry and the semi-finished products may for example also be provided in frozen form. The same applies to the finished product.

The present invention also relates to a method for preparing a food product, comprising the steps of:

a) shaping the puff pastry of the invention into a semi-finished food product; and b) cooking the semi-finished food product to obtain the finished food product.

The puff pastry can be shaped with a variety of shaping techniques, in particular kneading, forming, rolling out, filling, depositing in a baking mold, die-cutting, sheet-forming, molding.

The end product, i.e. the finished food product can be obtained by means of various cooking methods, such as baking, frying, deep-frying, etc. Suitably, the cooking is performed in an oven, such as an impingement oven or a convectional oven, in a frying pan, an air-fryer, a waffle iron, deep-fryer, hot plate, etc.

The present invention will be further illustrated in the Examples that follow and that are not intended to limit the invention in any way. In the Examples reference is made to the following figures:

Figure 1: Savory sticks with sprinkled sea salt and sesame seeds; and

Figure 2: Sweet palmiers with cane sugar and cinnamon. EXAMPLES

EXAMPLE 1

Preparation of the dry mix

For the preparation of the dry mix the following ingredients were mixed in dry form: 57% dehydrated potato;

28% potato starch;

7% potato protein;

3% amylopectin-rich potato starch;

3% monohydrate potato dextrose; and

2% salt.

This dry mix is used as the starting material for the preparation of various products.

EXAMPLE 2

Preparation of puff pastry

A puff pastry dough is prepared by starting to mix 250 g cold water (15°C) in a Hobart mixer with the butterfly kneading hook and slowly adding 250 g of the dry mix prepared in Example 1 and mixing for 2 min at a medium speed till a rough dough is obtained.

250 g Butter is cut into small cubes of 15x15mm, added to the rough dough and kneaded into the dough with a dough hook in 1 min. The dough is gathered in the bowl using one hand, then turned onto the work surface. The dough is then squashed into a flat sausage, without kneading. Wrapped in cling film the dough is chilled in the fridge for 15 minutes.

The work surface and the pastry are lightly floured with native potato starch. The pastry is then rolled it in one direction until it is about 1cm thick and three times as long as it is wide, or about 60x15cm. The top and bottom edges are kept as square as possible.

The bottom of the pastry is then folded up till the middle, then the top is also folded down to the middle, and the pastry is subsequently folded in the middle to place the dough pieces right on top of each other, making a block about 15x15cm. The corners should be nice and square.

The dough is then turned so that its open edge is facing to the right, like a book. The edges of the pastry are then pressed together with the rolling pin. The pastry is then rolled out and folded again, which is repeated three times in all to make a smooth dough, with buttery streaks here and there. Between the rolling sessions the dough wrapped in cling film has to rest for 15 min in the fridge. The finished pastry is chilled for at least an hour, or ideally overnight, before using.

To prepare savory sticks and sweet palmiers the pastry is rolled out to about the thickness of 2mm, shaped, filled, glazed, decorated and baked at 220°C for about 20 minutes.

The resulting product applications are shown in Figures 1 and 2.