WO2000021374A1

WO2000021374A1 - Method for production of potato pastes and equipment for execution of this method

Info

Publication number: WO2000021374A1
Application number: PCT/CZ1999/000037
Authority: WO
Inventors: Jiří VONDRÁČEK
Original assignee: ILJUŠKO, Ivan
Priority date: 1998-10-13
Filing date: 1999-10-13
Publication date: 2000-04-20
Also published as: AU6076699A; CZ328598A3

Abstract

According to a method of production of potato pastes dough made of a mixture of wheat flour and a potato-based ingredient is extruded through delivery nozzles of an extruder head and an extruded pressing is subsequently cut, pasteurised and dried and the pressing is surface stiffened at the output from the delivery nozzles, advantageously by a stream of the gaseous drying media, which stream can be dry air. The surface stiffening is performed on a pressing with the smallest thickness a = 1.5 mm and with a circumference of the cross section with a minimum size of four times the smallest dimension 'a'. An equipment for execution of the method consists of a cooled extruder with a head with delivery nozzles for extruding the pressings, whereas a device for crosswise cutting of the product is attached to the front face of the head, whereas a source (7) of gaseous drying media is attached to a head (3) provided with delivery nozzles (5), whereas the source (7) is arranged for directing the gaseous drying media onto front face (4) of the head (3) of the extruder (2).

Description

Method for production of potato pastes and equipment for execution of this method

Description

The invention relates to a method of production of potato pastes, in which dough made of a mixture of wheat flour and a potato-based ingredient is extruded through delivery nozzles of an extruder head and an extruded pressing is subsequently cut, pasteurised and dried. The invention further relates to an equipment for execution of the method of production of potato pastes consisting of a cooled extruder with a head with delivery nozzles for extruding the pressings, whereas a device for crosswise cutting of the product is attached to the front face of the head.

The document of the utility design CZ 5607 describes a dough-based product of a half-finished type that is made of non-boiled water-based flour dough prepared of wheat flour and a potato-based ingredient. To prepare a finished meal, the half-finished product is only boiled in water. The meal prepared from this half-finished product replaces the well- known potato dumplings and potatoes as a side dish. The main advantage of the above dough product consists in easy handling, storage and in an easy way of preparation of the meal that has the same taste as the today known ways of preparation of potatoes. The time for preparation of the dough product is shorter than that of the known dough products made only of corn flour and is much shorter that that of known potato dumplings. The mentioned dough product is produced by means of extruding to the required shape through delivery nozzles placed in the head of the extruder. The stuff extruded from the nozzles is subsequently pasteurised and dried. The disadvantage of this technique is that the substance extruded from the delivery nozzles does not have permanent physical properties and is difficult to be processed in the subsequent stages. When crosswise cut to short pieces, the extruded stuff is often deformed and does not keep the shape it obtains when passing through the delivery nozzles in the extruder head. The changes in the shape of the extruded stuff make no problem, if the changes occur in the crosswise direction, i.e. in the plane of the crosswise cuts. However, after leaving the nozzle, the extruded stuff also changes its length in the longitudinal direction before it is cut crosswise. The changes in shape of the extruded stuff are also accompanied by changing the surface quality that becomes sticky and causes that single pieces more or less stick together. After leaving the delivery nozzles in the extruder head or after going through next processing phases - pasteurisation and drying - the dough half-finished product often acquires too smooth, glossy, glass-like surface that leads neither water nor air. The reason of this phenomenon is presence of starch. No improvement was achieved by adding compounds that have a solidification effect. The half-finished product prepared from the stuff extruded through the extruder head delivery nozzles is usually also difficult to process. It does not keep its shape after being boiled, it often collapses into a flat cake and its taste can have a variable quality. The higher is the amount of the potato component, the longer time for boiling is necessary, however, final boiling is fast and the potato pastes soften quickly unlike the long time necessary to soften classical egg pastes that do not include the potato-based component. There was an attempt to find various ratios of the potato-based component and admixtures affecting the shape stability, however, the results were neither satisfactory nor reproducible. Measures were taken to improve the quality of the extruded stuff consisting in cooling the dough in the longitudinal cylindrical part of the extruder before the extruder head by means of water cooled cylinder walls. Cooling the dough in the cylindrical part of the extruder helped to achieve a partial improvement of physical properties of the extruded stuff, however, not sufficient for its reliable processing and more over, variability of the physical properties of the extruded stuff was not eliminated. The properties of the half-finished product after boiling in water were also not improved.

The object of the invention is to eliminate the drawback of the state of art and to secure a method of production of potato pastes made of a mixture of wheat flour and a potato- based component by extrusion through delivery nozzles of an extruder head and by subsequent cutting, pasteurisation and drying, which guarantees the stuff extruded through the delivery nozzles on the extruder head to have a constant quality and enable its further processing in wet condition, namely good loosiness, reliable and easy crosswise cutting, and to facilitate further handling during processing of the half-finished product by boiling and in preparation the final meal. The object of the invention also is a device for providing such method of production of the potato pastes, which enables production of easily divisible pieces of pastes with a constant quality, good loosiness and that have a constant shape and are easy to be processed by boiling as a half -finished product and that enable good qualities of the final product.

Disadvantages of the existing state of the art are significantly eliminated and the set objects of the invention are met by a method of production of potato pastes, in which dough made of a mixture of wheat flour and a potato-based ingredient is extruded through delivery nozzles of an extruder head and an extruded pressing is subsequently cut, pasteurised and dried according to the invention the principle of which consists in that the pressings are surface stiffened at the output from the delivery nozzles. According to an advantageous execution the pressings can be surface stiffened by a stream of the gaseous drying media, the gaseous drying media can be dry air. With advantage te surface stiffening is performed on a pressing with the smallest thickness a = 1.5 mm and with a circumference of the cross section with a minimum size of four times the smallest dimension "a" , surface stiffening can be advantageously performed on a pressing with a cross section with a square, rectangular or crescent shape. The equipment for execution of the method according to claim 1 consists of a cooled extruder with a head with delivery nozzles for extruding the pressings, whereas a device for crosswise cutting of the product is attached to the front face of the head, whereas a source of gaseous drying media is attached to a head provided with delivery nozzles, whereas the source is arranged for directing the gaseous drying media onto front face of the head of the extruder. According to an advantageous execution the delivery nozzles have the smallest dimension a = 1.5 mm in the cross section and a circumference with a minimum size of four times the smallest dimension "a" . The delivery nozzles can have a cross section with a square, rectangular or crescent shape.

The method of production of potato pastes according to the invention enables reaching a constant quality of the stuff extruded from the delivery nozzles of the extruder head, the pressings are easy to separate, they keep the shape, do not st^'ick together and their surface dries quickly so that they are acceptably loose and easy to transport and process . The above method of production of potato pastes can be used on equipment consisting of a cooled extruder with a head containing delivery nozzles. A tool for crosswise cutting of pressings is attached to the front face of the head, whereas a source of gaseous drying media focused on the front face of the extruder head is combined with the head. Direction, speed and amount of the drying media are determined according to the size of the extruder and according to the speed and volume of the extruded stuff. Advantageously, the delivery nozzles can have the smallest dimension a = 1.5 mm in the crosswise section and the circumference of the crosswise section with a minimum size of four times the smallest dimension "a" . Smaller dimensions of the delivery nozzles cause the pieces of pastes not to keep their shape after boiling. This phenomenon is more significant namely with potato pastes having the potato-based component that is the main reason why the potato pastes lose their shape after boiling. The design according to the invention enables the delivery nozzles to have a square, rectangle or a crescent shape of the cross section. It turned out that pressings with a circular crosswise profile lose their shape after boiling, even if they have a large diameter. It was discovered that the shape stability after boiling is affected namely by the ratio between the smallest thickness of the pressing and the circumference of its cross section. Properties of pressings, that are liable to changes of the shape, considerably change in case of ratios 4:1 (square) . The best properties of pressings and pieces of pastes after boiling were achieved by combining the surface stiffening of pressings and the ratio between the smallest pressing thickness and the circumference of its cross section higher than 4:1.

The invention is explained by means of drawings in which Figure 1 shows a view of the front face of the extruder head; Figure 2 shows a view of the front face of the head with square delivery nozzles; Figure 3 shows a view of the front face of the head with rectangular delivery nozzles and Figure 4 shows a view of the front face of the head with crescent delivery nozzles.

According to an example of embodiment of the invetion, the potato flour is first mixed with the wheat flour in weight ratios 1:1. Then ingredients affecting the dough property (e.g. eggs, salt, natural food colours, etc.) and subsequently water 20° C warm in the amount necessary are added to form the dough. Basically, the dough remains loose; it does not become a homogenous stretchy stuff. The dough in this condition is brought for extruding by the delivery nozzles 5 of head 3 of extruder 2 as shown in Figure 1. According to another example of embodiment, one weight part of wheat flour is first mixed with two weight parts of boiled grated potatoes, then one egg per each 2 kg of mixture, natural food colour (for example with the trade name "kurkuma") and salt are added and the stuff is mixed. When preparing the dough by mixing wheat flour and potato flour or boiled potatoes, it is necessary to reach such density that the dough does not form a homogenous block, but so that it enables single pieces to be separated. These pieces are basically loose and will form a homogenous stuff only by subsequent pressing. In case that boiled potatoes are added as a potato-based ingredient, the amount of added water has to be reduced, because the boiled potatoes already include about 40% weight parts of water. In case that potato flour is used as the potato-based ingredient, it is necessary to take into consideration that the potato flour is produced by drying potatoes and subsequent grinding of the dried product . Therefore, when dry potato flour is used as the potato-based ingredient, it is necessary to use more water, which is a normal technology procedure. The prepared dough is taken to the extruder body 2 and is extruded through the delivery nozzles 5 of head 3 of extruder 2. When output from the delivery nozzles 5 of head 3 of extruder 2 with a capacity of 100 kg/hr, the pressing according to the invention is stiffened by the stream of gaseous drying media. This gaseous drying media can be a stream of dry air generated by a standard type of fan. This stiffens the pressing that has a thickness a = 2 mm and a rectangular cross section with a circumference of 12 mm. The pressing remains sufficiently damp inside, but is dry on the surface to such extent, that it is loose. After extruding through the delivery nozzles 5 of head 3 of extruder 2 and surface stiffening according to the invention, the pressing is subjected in the subsequent steps to pasteurisation in the pasteurisation chamber by means of hot steam at 100° C, then pre-dried for about 15 minutes at approximately 30 - 40° C. The final drying is completed in the drying chamber for 8 - 10 hours at 40 - 60° C. After the pasteurisation and drying, the finished product was boiled. During this boiling, the product did not lose its shape, it did not become sticky and therefore it was easy to be picked up and its shape was not undesirably affected. According to Figure 1, the equipment for production of potato pastes consists of extruder 2 accommodated in cabinet 1. The extruder 2 -is fitted with head 3 with front face 5, in which delivery nozzles 4 are formed. Cutting device 6 for crosswise cutting of pressings is attached to front face 5. According to the invention, source 7 of gaseous drying media is attached to head 3 with delivery nozzles 5. This source is arranged to focus the media on front face 4 of head 3 of extruder 2. Direction, speed and amount of the drying media are determined according to the size of the extruder and according to the speed and volume of the extruded stuff. For the production volume of 100 - 150 kg/hr, it is possible to use a standard type of directional fan, whose inclination can be set depending on particular conditions, i.e. according to dimensions of the attached devices so that it is directed to the front face of the extruder head. Delivery nozzles 4 must have a minimum dimension in the crosswise section a = 1.5 mm and circumference of the opening in the cross section with a minimum size of four times the smallest dimension "a" . The cross section of delivery nozzles 4 can have a square, rectangular or crescent shape, as shown in Figures 2, 3 and 4. These shapes proved to be the most suitable to achieve the smallest necessary thickness and simultaneously the smallest necessary circumference of the finished product in the crosswise section.

Claims

Patent claims

1. Method of production of potato pastes, in which dough made of a mixture of wheat flour and a potato-based ingredient is extruded through delivery nozzles of an extruder head and an extruded pressing is subsequently cut, pasteurised and dried, c h a r a c t e r i s e d b y t h a t the pressing is surface stiffened at the output from the delivery nozzles.

2. Method of production of potato pastes according to claim 1, c h a r a c t e r i s e d b y t h a t the pressing is surface stiffened by a stream of the gaseous drying media.

3. Method of production of potato pastes according to claim 2, c h a r a c t e r i s e d b y t h a t the gaseous drying media is dry air.

4. Method of production of potato pastes according to one of claims 1, c h a r a c t e r i s e d b y t h a t the surface stiffening is performed on a pressing with the smallest thickness a = 1.5 mm and with a circumference of the cross section with a minimum size of four times the smallest dimension "a" .

5. Method of production of potato pastes according to claim 4, c h a r a c t e r i s e d b y t h a t surface stiffening is performed on a pressing with a cross section with a square, rectangular or crescent shape.

6. Equipment for execution of the method according to claim 1 consisting of a cooled extruder with a head with delivery nozzles for extruding the pressings, whereas a device for crosswise cutting of the product is attached to the front face of the head, c h a r a c t e r i s e d b y t h a t a source (7) of gaseous drying media is attached to a head (3) provided with delivery nozzles (5) , whereas the source (7) is arranged for directing the gaseous drying media onto front face (4) of the head (3) of the extruder (2) .

7. Equipment for execution of the method according to claim 6 c h a r a c t e r i s e d b y t h a t the delivery nozzles (5) have the smallest dimension a = 1.5 mm in the cross section and a circumference with a minimum size of four times the smallest dimension "a" .

8. Equipment for execution of the method according to claim 7, c h a r a c t e r i s e d b y t h a t the delivery nozzles (5) have a cross section with a square, rectangular or crescent shape.