NL1037939C2 - METHOD RESP. SYSTEM FOR THE TREATMENT OF A NUTRITIONAL FOODSTUFF. - Google Patents

Abstract

Method and system for treating a substantially solid food product (3) wherein cell disruption of the food product occurs and the building up of the necessary rise in temperature required for the processing of macro-nutrients. The system comprises means (8,10) that are arranged for subjecting the food product to a pulsed electric field for disruption of the cells of the food product and processing of the macronutrients, making it suitable for the intended consumption and efficient digestion, so that the body optimally takes in the nutrients.

Description

TITLE: Method resp. system for treating a substantially solid foodstuff

DESCRIPTION

5

The present invention relates to a method resp. system for treating a substantially solid foodstuff.

Food preparation includes all operations of preparing foods for consumption. The many different types of preparations include the heating of food (ingredients), but also other types such as the use of chemical, biological, mechanical means or techniques. For the preparation of food using heat, the words cooking treatment, cooking or cooking are also used.

15

Known methods for cooking or cooking food are roasting, baking, cooking (in hot or boiling water), deep-frying or roasting, smoking.

In the preparation of solid food by heating, as important in the present application, two processes, individually or together, can play an important role, namely tissue disruption and cell disruption, the concept of disruption being as disruptive, separation, rupture, splitting, crushing etc.

Tissue Disruption: Tissue consists of attached cells and can be made digestible by separating cells from each other.

Cell Disruption: Cells contain substances that become more accessible to humans (and animals) when the cells are broken open.

In the following, with regard to the treatment of solid food, particular attention will be paid to the preparation (possibly pre-cooking) thereof, in which cell disruption and / or tissue disruption can play a role, albeit in possibly different proportions with different food types ( meat, fish, vegetables, potatoes). In addition to cooking, treatment may also include the drying of food (for example meat, fruit), where cell disruption in particular appears to be important, or the pleating (skinning) of food (for example tomatoes, eel) in which preparation type, in particular tissue disruption, is important.

35 1037939 2

It is generally known to prepare solid food, in particular to cook, and to make it (better) suitable for human or animal consumption, by cooking and baking that solid food, for example meat, fish, potatoes, vegetables. and / or to roast, generally to heat such that the (cell resp.

The tissue structure of the relevant food is affected or damaged. disrupted - called (cell) disruption - to make the food sufficiently soft and digestible, the (macro) nutrients being released via the cell walls disrupted by the heating and then - also by that heating - converted into body-recordable modes.

10

Besides that heating of the food causes disruption of the cells of the foodstuff itself and thus makes the foodstuff more digestible, the heating may also be necessary to remove specific proteins and / or other substances in cells of microorganisms, such as bacteria, denaturing germs etc. (or changing them in such a way) that they lose their ability to divide cells and can no longer exert pathogenic influence on the consumer.

Although from time immemorial the treatment of both the cells of foodstuffs and the cells of harmful organisms has been effected by means of conventional heating (cooking, baking, etc.), there are some disadvantages to this. Thus, disruption due to heating costs a lot of energy, since the food in question must generally be heated for a longer period of time ("cooking through", "roasting"). In addition to keeping it at the required temperature for a longer time, bringing it up to that temperature also costs a lot of energy. Besides a lot of energy, the well-known processes of cooking and baking / roasting also cost a lot of time. Moreover, in particular by boiling in water, the taste and quality decrease, among other things because sometimes nutrients (proteins, carbohydrates, fats, micronutrients, bio-active substances, vitamins, minerals, etc.) end up in the (to be poured) cooking water and 30 by thermal degradation of such nutrients. Especially where larger groups of people (or animals) are served, where larger amounts of food have to be prepared and where food safety is of great importance, the food is often cooked for such a long time that serious damage to taste, structure ("bite ") and useful nutrients. An additional consequence is that where the taste perception of such food, for example of "junk food", is low, consumers tend to absorb more of such food in order to compensate for its low taste enjoyment 3 ("taste sensation"). with the result - as is the case today - many cases of obesity, etc. If too much structure is lost, there is a tendency to eat less of such food and there is a risk of malnutrition.

5

The present invention contemplates a greatly improved method of treatment - using heat; also provide cooking or cooking - of a substantially solid foodstuff.

According to the invention, a method is provided for treating a substantially solid food, comprising a step in which cell and / or tissue disruption of the food occurs, in particular (but not exclusively, see below) corresponding to the result of a cooking treatment for cooking the food, which method preferably comprises the steps of: a. placing the food in a treatment room which is adapted to generate a pulsed electric field (hereinafter also referred to as PEF for the sake of brevity); b. subjecting the foodstuff to a pulsed electric field with an electric field strength within a predetermined range, with a number of pulses within a predetermined range and with a pulse width within a predetermined range; such that the cell and / or tissue structure of the food in question is affected and / or disrupted corresponding to the result of a boiling treatment or thermal heating, to make the food, or a part thereof, soft, processable and / or digestible. .

Preferably, the term "treatment" used includes the preparation, pre-cooking or cooking of the foodstuff, for example of a meat, fish product or potato, vegetable, and / or drying thereof. It has further been found that the method 30 also lends itself to loosening, for example, the skin of fish (eel) and the outer sheets of tomatoes ("pleated") and fruits (plum), so that the term "treating" is also understood to mean these applications. include. In general, "treating" can be defined here as converting and / or preparing the relevant foods in such a way that they: 35 a. Better match the wishes and needs with regard to consumption and / or (for example industrial) processing thereof and 4 b . through the digestive tract of humans (or animals) the food components (proteins, starches, fibers) become (better) available for and can be used by the body.

c. the cell and / or tissue structure of the food in question is affected and / or broken corresponding to the result of a boiling treatment or thermal heating, to make the food, or a part thereof, soft, processable and / or digestible

It is noted that it is known per se to subject foods, both liquid and (semi-) solid to a pulsed electric field (PEF): US5549041 discloses a device for subjecting solid and semi-solid foods to a pulsed electric field formed by means of a series of high-voltage pulses which are applied to two electrodes which are arranged in a treatment chamber on either side of the relevant foodstuff. The (pulse-shaped or pulsed) fields generated by the high-voltage pulses have field strengths in the range of 20-100 kV / cm. The object of the proposed device is to provide a "food processor" for effectively controlling the growth of microorganisms. There is no mention of the use of PEF for treating food as described above.

US6083544 discloses a method for improving a "meals-ready-to-eat (MRE) rotational retort process" wherein a PEF process is (also) used to inactivate microorganisms, thereby sterilizing the food. Also from this publication the use of PEF for treating food or foodstuffs, such as in particular, the (pre) cooking thereof, is not known. On the contrary, this publication states that "the resultant product of the PEF process is not ready to eat". The field strength range specified in this publication is 20-45 kV / cm.

WO9949561 discloses a system for generating bipolar high-voltage pulses for inducing "stress and mortality in biological cells". This system is also intended for pasteurization and / or sterilization, i.e. for killing microorganisms; not for handling (such as pre-cooking or coming-off etc.) of food.

35 The Applicant has, to the great surprise of himself and of PEF and food experts, found that subjecting food to a series (or series) of PEF

Pulses, precisely of relatively low field strength, result in the food in question being cooked as if it were cooked / cooked in a known manner or prepared only using heat. In addition, the treatment time - resulting in a good "ready-to-eat" product - is exceptionally short and taste and nutritional value are well preserved. Although tests are still in progress, it appears that the "PEF cooking process" proposed here, i.e. the cooking of food by means of. PEF without having to bring the food to a high (cooking) temperature - which process is introduced under the name "e-Cooking" ®, which name will also be used hereinafter to indicate the method or method. device according to the present invention - to be eminently suitable for, for example, cooking (cooking) fish and meat. However, e-Cooking® is also excellent for cooking (cooking) potatoes and vegetables, again without having to bring them to a high cooking temperature of 100 ° C. Apart from that, it has been found that, for example, tomatoes can be peeled effortlessly by means of PEF pulses, which is important for the further industrial processing of tomatoes.

Advantages of the proposed combined mainly electric field pulses for breaking the cell walls (1) and for generating (just enough) heat for the conversion of the contents of the disrupted cells necessary for absorption into the body ( 2) - method are: the e-Cooking® (PEF) method according to the invention is heated volumetrically: the core temperature and the temperature at the edge of the product are virtually the same; the e-Cooking® (PEF) process works very quickly: the food does not have to be heated to conventionally high temperatures (water 100 ° C and baking / roasting 170-200 ° C); the e-Cooking® (PEF) method is energy efficient: only accurate energy supply to only the food and the immediately surrounding liquid. In addition, the food does not first have to be brought (for a longer period of time) up to or above boiling / baking / roasting temperature and then cooled again to the desired serving / consumption temperature; the e-Cooking® (PEF) method only uses cell structures and some nutrients, such as proteins, starches, enzymes, very accurately and in a controllable manner; 6 With the e-Cooking® (PEF) method, the desired nutritional value, taste and texture are preserved much better than a conventional cooking treatment such as cooking / roasting / baking.

Preferably, the foodstuff is heated by the pulsed electric field with a temperature rise within a predetermined range or heated to a final temperature within a predetermined range, so that the foodstuff is suitable for its intended consumption and / or processing thereof. In particular, the predetermined temperature rise range is 10 - 100 ° C and the predetermined end temperature range is 35 - 100 ° C.

The food is subjected to a PEF treatment so long that the temperature of the food has risen by a predetermined value or that the temperature has reached a predetermined final temperature.

The invention also relates to the use of a pulsed electric field for the treatment of foodstuffs and to a system suitable for the treatment of a foodstuff according to a method of the invention.

In the following, the invention will be further discussed on the basis of a simple exemplary embodiment of an installation for treating a food product using an e-Cooking® (PEF) system designed for this purpose. The system shown, by the way, shows a lot in common with the system shown in US 5549041; however, it is used there to kill microorganisms at very high electric field strengths compared to the e-Cooking® method proposed here, while here using considerably lower field strengths is used for cooking (cooking etc.) of food.

Figure 1 shows schematically an exemplary embodiment of an installation for treating a foodstuff by means of an e-Cooking® system based on the use of PEF;

Table A shows an overview of a number of food treatments using an e-Cooking® device.

35 7

The exemplary embodiment of a system for treating a foodstuff in which cell disruption occurs, shown in Figure 1, comprises a treatment space 1, surrounded by an outer housing 2 that can be accessed from outside and can be closed, which is arranged for placement and removal after treatment thereof of the foodstuff 3. Inside the outer housing 2 is a second, electrically insulated process chamber 4 which can be closed by means of a cover 5. At the bottom of the process chamber 4 is an earth electrode 6; a voltage electrode 7 is located at the top of the process chamber 4, against the lid 5. Preferably, the space in the process chamber 4 that is not occupied by the food 3 is supplemented with an amount of ambient liquid or broth to prevent air inclusion and undesired electrical breakdown. from air.

The process chamber can, if necessary, be actively vented beforehand by applying an underpressure. In addition, an overpressure can also be applied in the chamber during the process. By applying both underpressure and overpressure, the exchange of substances can be promoted, among other things.

How exactly the cover 5 and the electrode 7 can be moved up and down and how the electrode 7 is mechanically and electrically connected to a (below to be treated) PEF generator 8, is of less importance and is not shown in detail. Further preferred embodiments which have since been developed are the subject of another patent application by the applicant of the present patent application.

The means for generating one or more pulsed electric fields 25 is formed by the PEF generator 8, which is accommodated in a housing 9. The exemplary embodiment of the PEF generator shown is taken from www.fao.org/ag/-iags/ agsi-i / Nonthermal / Nonthermal Figurell.gif, wherein DC is a direct current source and S is a switch; furthermore the diagram shows a number of capacitors, self-induction coils and resistors, with which a desired pulse shape can be realized. One of the circuits shown in WO9949561 could also be used, albeit for a different purpose and with different values for the generated voltages and field strengths than as indicated there. It is, however, possible, as indicated in WO9949561, to have the PEF generator generate 8 bipolar pulses instead of unipolar pulses. 35 8

The PEF generator 8 is connected to a control module 10 (located inside or outside the housing 9) which is adapted for control or control. setting up such pulsed electric fields. The control module 10 can be computer-controlled and can be set by means of a usual integrated or 5 external terminal, touch screen interface or PC. Means for applying such controllable pulsed electric fields to the foodstuff 3 placed in the process chamber 4 are formed by plate-shaped electrodes 6 and 7 which are connected to the PEF generator 8 via lines 11 (ground) and 12 (high voltage).

The different components are adapted to subject the food 3 to a pulsed electric field of sufficient electric field strength and with a sufficient number of pulses to cause disruption of the cells and to build up a necessary temperature increase of the food that the food is then converted and is therefore suitable for the intended human or animal consumption and efficient digestion, so that the body optimally absorbs the valuable nutrients from the cells.

As explained above, the treatment of food is based on a specific high-frequency administration of high-voltage pulses such that the structure of animal and plant cells changes. Cells can separate from each other (for example with "flaky" cod) and cell walls can be opened, making the cell contents accessible. But a relatively low temperature (54 - 80 ° C) can also be accurately built up (due to ohmic heating) in which substances change their structure (proteins, starch, pectins, fibers) and thereby become (better) digestible. At the same time, other substances such as vitamins, bioactive substances and other micro-nutrients are affected as little as possible at this temperature and time.

The energy supply is only used for the food product itself and for its direct ambient liquid (against electrical air breakdown). This makes a huge energy saving possible. It is estimated that it is possible to use one third to one sixth of the energy compared to conventional electric cooking. This does not yet take into account the extraction of hot, humid air, which arises to a much lesser extent with e-35 Cooking® than with conventional cooking etc.

9

Because cooking "on demand" (only start with meal preparation on request and only what is needed) becomes possible, less food waste can be achieved.

e-Cooking®, as the present new method is called, is a safe method of food preparation because only the food becomes hot and not the environment (the pan).

The foodstuff is thus subjected for a short time to one or more pulses with an electric field strength suitable for the present purpose. This field strength is considerably lower than the field strengths used (see the treatment of the prior art) for decontamination of foodstuffs by killing off unwanted microorganisms, for which field strengths of 20 kV / cm and higher are used. The method proposed here thus uses a combination of disrupting (disruption) of food cells (cell walls) and / or tissue by the applied field strength (<20 kV / cm) and - preferably - causing ohmic heating, whereby very homogeneous cooking of the foods can be achieved. In practice, the present method for food preparation can be successfully applied by using pulses with field strengths from about 200 V / cm.

20

To achieve the desired cooking of products, the following predetermined parameters must be set correctly: a. The field strength; b. the pulse width; C. the pulse shape (preferably with steep flanks; optionally also the pulse frequency; d) the net treatment time, ie the pulse width multiplied by the number of pulses; e. the possible pause time between the pulses in view of the load on the device receiving the pulses. must deliver or for the purpose of intermediate relaxation (mortification) of the food f) the conductivity of the surrounding liquid / broth g) the starting temperature of product and liquid.

The amount of energy supplied to the product has to do with the available power of the developed system. This power is quadratic influenced by the applied voltage. This voltage is again partly determined by the height of the product.

Example 1 A beef stew should normally stew in a pan for 4 to 5 hours to cook, i.e., and thus make it edible and digestible in the body. Treatment in an e-Cooking® device as shown in Figure 1 with 1000 pulses of 10 ps with a pause time of 0.1 sec between the pulses took 100 seconds or 1.7 minutes. The core temperature here has become 75 ° C and the surrounding liquid 10 only 56 ° C. This result is amazing, also for professionals from the meat industry who were confronted with this.

Example 2

According to professional chefs, when 'poaching' cod, it is very important that the temperature does not exceed 54 ° C. With the e-Cooking® device this can be achieved very well and uniquely. The result is a beautiful "flaky" product.

Example 3

This example concerns the treatment of 'cooking' a potato slice. After the treatment in the e-Cooking® device with 1700 pulses of 10 ps and a pause time of 0.1 sec between the pulses, it took 170 seconds or 2.8 minutes. The core temperature here has become 87 ° C and the surrounding liquid only 79.5 ° C.

Example 4 The treatment of vegetables with the e-Cooking® device also gives a good result. A somewhat higher chamber (4 cm) was used here, so that the field strength was lower (with the same voltage across the electrodes). As a result, more pulses were needed and the yarn took a little more time, namely about 5 minutes. The core temperature of broccoli and Brussels sprouts in this example was 88 ° C.

30

Table A gives an overview of the above-mentioned examples of food preparation with the "e-Cooking®" method according to the invention proposed in this patent application, practically carried out in a laboratory copy of an "e-Cooking®" device. In addition to the very specific pulse conditions mentioned here, similar effects have also occurred in other conditions (milliseconds, pulses 4-60 units at 2 kV / cm).

11

Field - Pulse - Product - Broth - Color,

Feeding Quantity- Number Pause- Cooked- Struc- Strength width tempera- ture odor, medium (g) pulses time (s) hour (kV / cm) (ps) ture (° C) ture (° C) taste

Stew 90 1, 75 IÖ 1,000 Ö7 "ï 75 56 Good Good Good

Perfect Very

Cod 49 0, 88 10,000 40 1.0 52 45 Good "flaky" good

Potato 80 1, 75 IÖ 1,700 ÖTÏ 87 79 Good Good Good

Vegetables 31 0, 88 10 3,000 0, 1 88 88 Good Good Good (Broccoli, Brussels sprouts 45 0, 88 10 4,000 0, 1 88 82 Good Good Good

Table A 5 1 0 3 7 9 3 9

Claims (13)

Method for treating a substantially solid foodstuff for consumption and / or processing thereof, comprising the steps of: - placing the foodstuff in a treatment space that is adapted to generate a pulsed electric field; - subjecting the foodstuff to a pulsed electric field with an electric field strength within a predetermined range, with a number of pulses within a predetermined range and with a pulse width within a predetermined range; such that the cell and / or tissue structure of the food in question is affected and / or broken corresponding to the result of a cooking treatment or thermal heating, to make the food, or a part thereof, soft, processable and / or digestible. 2. Method as claimed in claim 1, wherein the foodstuff is heated by the pulsed electric field with a temperature rise within a predetermined range or is heated to a final temperature within a predetermined range, and is suitable for its intended consumption and / or processing. 3. A method according to claim 2, wherein the predetermined temperature rise range is 10 - 100 ° C and wherein the predetermined end temperature range is 35 - 100 ° C. The method according to any of the preceding claims 1-3, wherein the predetermined range of the electric field strength is 0.2 - 20 kV / cm, preferably 0.5-5 kV / cm. 30 The method according to any of the preceding claims 1-4, wherein the predetermined range of the number of pulses is 1 - 10,000. 6. Method according to any of the preceding claims 1-4, wherein the predetermined range of the pulse width is 1 - 20,000 ps. 1 0 3 7 9 3 9 A method according to any of the preceding claims 1-6, wherein the foodstuff is pot roast and wherein the predetermined range of the number of pulses is 100-5000, and wherein the predetermined range of the pulse width is 1-100 ps. 5 A method according to any of the preceding claims 1-6, wherein the foodstuff is fish and wherein the predetermined range of the number of pulses is 1 - 500, and wherein the predetermined range of the pulse width is 500 - 20,000 ps. The method of any one of the preceding claims 1-6, wherein the foodstuff is potato and wherein the predetermined range of the number of pulses is 200 - 10,000 and wherein the predetermined range of the pulse width is 1 - 100 ps. A method according to any one of the preceding claims 1-6, wherein the foodstuff is vegetable and wherein the predetermined range of the number of pulses is 500 - 10,000 and wherein the predetermined range of the pulse width is 1 - 100 ps. A method according to any of the preceding claims 1, 4 - 6, wherein the food is tomato or fruit and wherein the predetermined range of the number of pulses is 1 - 100 and wherein the predetermined range of the pulse width is 1 - 100 ps, such that the tomato or fruit can easily be peeled off. The use of a pulsed electric field for the treatment of food products according to a method of any one of the preceding claims. 13. System suitable for treating a foodstuff by applying a method according to one of the preceding claims 1 - 11. 30 1 0 3 7 9 3 9