AU2017201309A1

AU2017201309A1 - Method and apparatus for making a low density wafer product

Info

Publication number: AU2017201309A1
Application number: AU2017201309A
Authority: AU
Inventors: Abdessamad Arrachid; Stephen Coe; Rodolfo De Acutis; Richard Leadbeater; Hugh Powell
Original assignee: Nestec SA
Current assignee: Societe des Produits Nestle SA
Priority date: 2010-07-02
Filing date: 2017-02-27
Publication date: 2017-03-16
Anticipated expiration: 2031-06-28
Also published as: AU2015203284A1; AU2017201309B2

Abstract

Abstract The present invention relates to t he production of wafers and more particularly to t he use of a batter aerating system to obtain wafers with an effective density of at most 0.16 g/cm3, and with sufficient strength to be able to remove them from the wafer baking plates.

Description

2017201309 27 Feb 2017 1

METHOD AND APPARATUS FOR MAKI NG A LOW DENSI TY WAFER PRODUCT

The present application is a divisional application of Australian Application No. 2015203284, 5 which is incorporated in its entirety herein by reference.

Technical field of the invention

The present invention relates to the production of wafers and more particularly to a method for aerating the batter to maintain an aerated structure of wafersduring their production. 10

BackgOund of the invention

In International Jburnal of Food Sdence and Technology 41, p.569-576 (2006), Ismail S Dogan defines a wafer as low-moisture-baked foods being formed from a batter and baked between hot plates. It is further disclosed that the quality of wafer sheets is mainly controlled by flour 15 property, water level and temperature, mixing action, baking time and temperature. The quality of the wafer is a result of attributes of the batter such as the density, viscosity, holding time and temperature, and by properties of the wafer such as weight, surface colour, fragility and moisture content. The study condudesthat wafers have little in common with other types of biscuits in regard to the formulae and processing, and that water level and gluten content are important for 20 obtaining a high-quality wafer sheet.

Duncan Manley disdose in the book “Technology of biscuits, crackers and cookies;’ (p.296,3rd Ed., Woodhhead Flib. Ltd.) that creation of gas cells in gelatinised starch is most important in wafer manufacture. Although bubbles of air are induded during batter mixing most of these float 25 out of the batter before it isdeposited onto the plates. If the conditions are such that insuffident time is allowed for the bubbles to leave the batter it could be that the density of the batter changes during use and this will affed the baked sheet weights in terms of giving variable and uncontrolled texture. He further statesthat chemical aeration is usually achieved with sodium bicarbonate or ammonium bicarbonate or a mixture of the two. Ammonium bicarbonate is 30 particularly effective. Experience has shown that attention to the combination of batter 2017201309 27 Feb 2017 2 consistency and ammonium bicarbonate level is the best way to control batter spread and wafer sheet weight. Increasing the amount of these aeration chemicals increasesthe aeration, but again the texture of the wafer will be un-processable above acertain level, by which time the distinct and unpleasant off-flavour given by these chemicals becomes unpleasant and unpalatable for a 5 foodstuff. Tbe use of yeast as a method of aeration by the creation of carbon dioxide in the batter during fermentation issteeped in tradition. Batter standing time and suitable temperatures to allow multiplication of the yeast are not usually very practical in modern mixing and batterhandling systems, especially when producing wafer on an industrial scale. Yeast is now rarely used in batter recipes. 10

It is known that adding extrawater to a wafer batter mix will reduce the effective density of a wafer sheet. In the process of baking any wafer from water based batter, when the batter is heated the water turns to steam, the steam forms bubbles in the mix and these bubbles then form the cavities^cells in the wafer structure. Tbe more water there is in a batter, the more steam 15 isgenerated, and the steam generates more cavities^cells in the final wafer resulting in the batter having a reduced density. Tbe outer layers of the wafer are also thinner which gives the wafer a lighter texture. Low density wafers give a lightness and crispiness to some wafer products that is desirable to the consumer. 20 However, there is a lower limit to the effective density of finished wafer that this method makes. As more and more water is added, the structure of the cavities^cells that are generated becomes less uniform throughout the wafer as the process of the formation of the cells by the steam is not well regulated or controlled. A wafer made in such away isfragile due to the irregular cell structure and large cel Is that extend through the wafer. 25

Additionally, as more water is added to the batter mix, it is more difficult to control the process and bake wafers of consistent quality. Another added complication isthat, if more water isadded to the batter, then the viscosity of the batter decreases and it becomes difficult to handle and deposit a low viscosity liquid onto the baking plates. Unwanted dripping of the batter will occur at 30 the point of deposition causing waste and oven fires. 2017201309 27 Feb 2017 3

The result of these methods of producing very light wafersthrough the use of high dilution or high addition of aeration chemicalswafersisan inhomogeneous content of cavities^ cel Is which reduces robustness and causes breakage when subjected to further handling, such as simple removal from the baking plate. 5

Aeration by these well-known methods therefore has its limits before the quality of the wafer in terms of texture and flavour is compromised, and also becomes too fragile to handle in the industrial process, such as simple removal from the baking plate. Low density wafers of density <0.16g/cm3 aretherefore not known in existing technology. 10

Summary of the invention

Accordingly, one aspect of the invention relatesto a method for the production of awafer, the method comprises the steps of: 15 (i) providing a batter mix comprising at least flour and water; (ii) subjecting the batter mix to an aeration treatment obtaining an aerated batter mix; (iii) optionally subjecting the aerated batter mix to mixing; 20 (iv) feeding the mixed and aerated batter mix to a heated baking surface through a batter depositor; and (v) baking the mixed and aerated batter mix to obtain awafer; 25 wherein the aeration treatment in step (ii) isdown-stream from any direct pumping of the method.

Another aspect of the present invention relatesto an apparatusfor the production of awafer 30 which comprises: 4 2017201309 27 Feb 2017 (i) a storage vessel comprising a batter mix; (ii) an aeration device responsible for an aeration treatment; 5 (iii) a batter feed pump for providing the batter mix from the storage vessel to the aeration device; (iv) a batter depositor for depositing the aerated batter mix onto a heated baking surface. 10

Yet another aspect of the present invention isto provide awafer having: (i) a breakage force of at least 1N;

15 (ii) an effective density of at most 0.16 g/cm3 when measured at 20°G

Brief description of the figures 20 Figure 1 shows a schematic example of an apparatus for producing alow effective density wafer. The present invention will now be described in more detail in the following.

Detailed description of the invention 25 As mentioned it isof interest to provide a method for obtaining robust wafer, and wafers as such, which do not break when subjected to further handling, such as simple removal from the baking plate, even at low densities, and which also do not suffer from distinct off-flavour caused by added aeration chemicals or increased use of yeast in the recipe. 30 To lower the effective density of awafer, one will need to reduce the amount of flour deposited on the plate whilst maintaining the complete wafer shape in the baking mould. The current 2017201309 27 Feb 2017 5 technology solves this problem by adding more water to the batter mix (diluting the batter), by increasing the concentration of the chemical leavening agents such as sodium bicarbonate or ammonium bicarbonate or by using yeast or by any combination of these. 5 The conventional technology teaches an aerated structure in the wafer, wherein the aeration is created during the moment of baking, i.e. once the batter hitsthe heated baking surface. This is obtained by the steam generated within the baking mould. Alternatively aeration is achieved by chemical leavening agents, the action of which is set off by the heat of the baking plate or yeast, both of which leave the wafer with different off flavours. Furthermore, it is believed that the 10 steam generated from the added water and the high pressure between the baking plates, at the moment of baking, destroys any existing bubbles in the wafer batter.

The inventors of the present invention have surprisingly found that the pre-existence of bubbles in the wafer batter leadsto the formation of a more homogenous distribution of cavity/cell 15 and/or more homogenous size of the cavities^cells in the wafer. The effect of the more homogenous distribution and/or size of the cavities^cells in the baked wafer makesthe wafer much stronger compared to a conventionally baked wafer with the same effective density. This allows one to make complete wafers of a lower effective density than ever before, and still be able to remove them from the wafer baking plates. 20

The cellular structure can be further strengthened using known stabilisers such as starch, modified starch, gums such as locust bean gum, guar gum, gum acacia, tragacanth, xanthan, karaya, gellan, tars, cellulose and cellulose derivatives, pectin or gelatin, maltodextrins, gelling agents such as alginates or carageenan, proteins or protein sources such as albumins, casein, 2 5 caseinates, milk powders or whey powders.

Flowever, in practice it is very difficult to use the beneficial effect of bubbles in the batter. This is because in conventional baking equipment, a lobe-type deposition pump is placed at the end of the line, and thistype of pump isfound to destroy the bubbles in the aerated batter. Thus, by 30 having the aeration treatment in step (ii) down-stream from any direct pumping, such asthe lobe-or impellor-type deposition pump, it may be possible to avoid that bubbles introduced into the wafer batter are destroyed during the deposition. By direct pumping we mean pumping by a lobe 2017201309 27 Feb 2017 6 pump or impellor pump or progressive cavity pump or diaphragm pump or peristaltic pump or gear pump.

Tbe second problem preventing the inclusion of aeration in wafer batter prior to baking isthat in 5 most conventional wafer baking equipment the wafer baking plates are individually moving, with spaces between, so that the deposition has to go intermittently (start at beginning of plate, stop at end of plate). To avoid depositing batter between the plates, the deposition pump has to work intermittently. To maintain consistent aeration however, the pressure of the system must remain constant which requiresthe pumpsto run continuously. Therefore a solution to this is required 10 whereby the aeration of batter iscontinuousyet the deposition of the aerated batter can be started and stopped in a controlled manner. Whilst more diluted batters will also drip between plates causing waste and oven fires, aeration of the batter inaeasesthe viscosity of the batter, removing this issue. 15 In apreferred embodiment of the present invention the method is a conventional wafer baking oven of moving plates.

To control the process of deposition onto the baking plate, so that the batter may only deposited on the baking plates and not in between, a piston accumulator can be introduced. 20

This piston accumulator works as a buffer system which introduce breaks in the deposition of aerated batter onto the hot baking plates, while the pumps (e.g. deposition pump, batter pump, etc.) continuously pumps the batter. The use of a piston accumulator results in a pumping process which is kept continuous even though the deposition is intermittent., thereby maintaining the 25 aeration of the batter.

The present invention relates to a method for the production of a wafer, the method comprises the steps of: 30 (i) providing a batter mix comprising at least flour and water; (ii) subjecting the batter mix to an aeration treatment obtaining an aerated batter mix; 2017201309 27 Feb 2017 7 (iii) optionally subjecting the aerated batter mix to mixing; (iv) feeding the mixed and aerated batter mix to a heated baking surface through a batter 5 depositor; and (v) baking the mixed and aerated batter mix to obtain a wafer; wherein the aeration treatment in step (ii) isdown-stream from any direct pumping of the 10 method.

In one embodiment of the present invention, there is no direct pumping of the batter mix after the batter mix has been subjected to the aeration treatment. 15 In another embodiment of the present invention, the aeration treatment isjust before the batter reaches the batter depositor, such as within 5 minutes before deposition onto the heated baking surface, such as in the interval of 5 seconds to 4 minutes before, preferably within 2 minutes before, such as in the interval of 10-60 seconds before, preferably within 60 seconds before, more preferably within 30 seconds before, and most preferably within 15 seconds before depositing 20 onto the heated baking surface. In an embodiment of the present invention, the aeration treatment may form part of the batter deposition.

As mentioned, direct pumping of the foam or aerated batter will destroy the cavities^cells in the batter and therefore in the wafer, or at least cause undesirable-in terms of consistent batter 25 quality - inhomogeneous distribution of the size distribution of the cavities^ cells in the batter and therefore in the wafer. Hence, in still another embodiment of the present invention, the method does not involve any direct pumping of the aerated batter mix and/or any direct pumping of the aerated primary foam. 30 In yet another embodiment of the present invention, the aeration treatment involves preparation of a primary foam. 2017201309 27 Feb 2017 8

In one embodiment of the present invention, the aeration treatment involvesthe U9e of a medium to high-shear mixer with an aerating agent.

In apreferred embodiment of the present invention, the primary foam comprisesafoaming 5 agent and water. In a more preferred embodiment, the foaming agent is selected from the group consisting of aprotein containing milk composition, such as sodium caseinateor HYBOAMA, cellulose, wheat proteins and albumens.

In one embodiment of the present invention, the primary foam may be prepared by pumping a 10 foaming agent and water through a“Mondomix” mixing head. The liquid phase (foaming agent and water) and a gas phase merge at the inlet of the mixing head and are homogenized with accurate flow control under controlled pressure. The Mondomix mixing head isthe world standard, and consists of a rotor and stator both fitted with intermeshing pins, which provide, unlike other systems available, constant sheer to the product. This results in better temperature 15 control and controllable bubble size distribution.

Preferably, the primary foam hasafoam overrun above 100% such as above 150% e.g. above 200% such as above 300% e.g. above 400% such as above 600% e.g. above 800% such as above 1000% 20

In the present context the term “overrun” refers to the volume increase, from the change of phase from liquid to foam and isdefined in the following formula: Q/errun (%) = ((Volume after aeration - volume before aeration) / volume before aeration) * 100 25 In yet another embodiment of the present invention, the gas merging with the liquid phase at the inlet of the Mondomix mixing head is selected from the group consisting of helium, nitrogen, carbon dioxide, air and argon. 30 The present invention is illustrated with reference to the accompanying drawing in which Figure 1 depicts an apparatus for the production of a low density wafer. Fteferring to the drawing, a storage tank (10) for a batter mix is provided with a feed pump (11). A storage vessel (12) for a 2017201309 27 Feb 2017 9 solution of one or more foaming agents may be provided with adosing pump (13) adapted to run at the same time as the feed pump (11). fbe solution may be pumped through a Mondomix mixing head (14) and a pinch vaive (15) maybe used to regulate the back pressure in the Mondomix mixing head (14). Tbe produced foam maybe passed through an injection nozzle (17) 5 into the batter feed pipe (19) for transporting the batter mix. Downstream of the injection nozzle (17) in the batter feed pipe (19) may bean in-line static mixer (18) for blending the primary foam with the batter mix to form the aerated batter. Down-stream of the in-line static mixer (18), the batter feed pipe (19) leadsto abatter arm (21), positioned to deposit batter onto a heated baking surface (not depicted). Tbe apparatus may further comprise a piston accumulator (20) for control 10 of deposition of batter onto the heated baking surface.

One aspect of the present invention relatesto an apparatusfor the production of awafer which comprises: 15 (i) a storage vessel comprising abatter mix; (ii) an aeration device responsible for an aeration treatment; (iii) a batter feed pump for providing the batter mix from the storage vessel to the aeration 20 device; (iv) abatter depositor for depositing the aerated batter mix onto a heated baking surface.

In one embodiment, the flow of batter through the overall system may be driven by pumps up-25 stream to the aeration treatment.

In afurther embodiment of the present invention the flow of batter through the depositor may be controlled (stopped and started) by an accumulator system.

In afurther embodiment of the present invention, the flow of batter through the system may be 30 driven by pumps up-stream to the aeration treatment and the flow of batter through the depositor may be controlled (stopped and started) by an accumulator system. 2017201309 27 Feb 2017 10

The inventors of the present invention found that mixing of the aerated batter prior to deposition on the hot plates offers further advantages because it provided abetter and more homogenous distribution of the cavities cells in the aerated batter. In this way the wafer produced using mixing of the aerated batter may provide an even stronger wafer which may have an even lower 5 effective density.

In an embodiment of the present invention the method further comprises mixing of the primary foam and the batter.

In another embodiment of the present invention, the apparatus further comprises mixing of the 10 batter-foam mix and the mixing is provided by an in-line mixing device, the in-line mixing device should gently mix in the primary foam to form a homogeneous batter. In a specific embodiment of the present invention, the in-line mixing device isastatic mixer. Samples of static mixers and the function of such static mixers may be found in EP2105051. 15 Preferably, the static mixer may be located down-stream to the piston accumulator.

In yet another embodiment of the present invention, the apparatus further comprises a storage vessel for further batter ingredients 20 In another embodiment of the present invention, the apparatus comprises a dosing pump for feeding the further ingredients to the batter mix or the aerated batter mix.

In yet another embodiment of the present invention, the apparatus further comprises meansfor removing baked wafer from the heated baking surface. 25

In still another embodiment of the present invention, the aeration device may be comprising a Mondomix mixing head.

In still another embodiment of the present invention, a pinch valve may be located prior to the 30 mixing phase, post aeration of the aerating agent to maintain pressure. 2017201309 27 Feb 2017 1 1

In another embodiment of the present invention, the heated baking surface is a wafer baking mould comprising two plates locked in position to constrain the batter during the baking time.

Tbe quality of wafer sheets may be controlled by flour property, ratio of water to flour in the 5 batter and batter temperature, mixing action, baking time and temperature. Tbe quality may be judged by attributes of the batter such as the effective density, viscosity, holding time and temperature, and by properties of the wafer such as weight, surface colour, fragility, breakage force and moisture content. 10 Tbe inventors of the present invention have found that the pre-existence of bubbles in the wafer batter leadsto the formation of a more homogenous distribution and/or size of cavity/cell in the wafer. Tbe effect of the more homogenous distribution and/or size is to make the wafer much stronger compared to a conventionally baked wafer with the same effective density. This allows one to make wafers of a lower effective density than ever before, and still be able to remove 15 them from the wafer baking plates.

Oie aspect of the present invention relatesto awafer having: (i) a breakage force of at least 1N; 20

(ii) an effective density of at most 0.16g/cm3when measured a 20°G fbeterm breakage force is to be understood in the context of the present invention asthe force required to break the wafer and is measured by a 3-point bend test as detailed below. Die 3-point 25 bend breakage test is performed with aTA.HD Plus Texture Analyser from Sable Micro Systems (http://www.stablemiaosvstems.com/), using athree point bend rig and Exponent software to drive this rig as supplied by this company. Tbe force is applied to the centre of awafer suspended at two points 10 cm apart on strutshaving horizontal 1cm diameter cylinders. Tbe size of the wafer piece is 20cm by 8cm, and it is placed evenly over the struts. Tbe probe also has a 30 horizontal 1cm diameter cylinder. Atesting speed of the probe of 1.00 mm/second is used together with a 50kg load cell (also supplied by Sable Miao Systems). 2017201309 27 Feb 2017 12

Hie breakage force relates to the stiffness of the wafer which governs processability.

In the context of the present invention, the term “effective density” (peff)” relates to the weight of sample divided by the “envelope volume of sample”. Tbe envelope volume of the sample relates 5 to the volume defined essentially by the outer surfaces of the sample and includes any porosity within the sample.

In one embodiment of the present invention, the wafer has a breakage force of at least 1N, such as in the range of 1-4N, preferably in the range of 2-4N, and/or an effective density of at most 10 0.16g/cm3, such as in the range of 0.08-0.15 g/cm3, preferably in the range of 0.12-0.15g/cm3.

In another embodiment of the present invention, the wafer has a homogenous distribution of bubbles^ cavities. 15 In yet another embodiment of the present invention, the wafer has a homogenous size of bubbles^ cavities.

It should be noted that embodiments and features described in the context of one of the aspects of the present invention also apply to the other aspects of the invention. 20

All patent and non-patent references cited in the present application, are hereby incorporated by reference in their entirety.

Tbe invention will now be described in further details in the following non-limiting examples.

Examples fbe following B<amplesare provided of illustrative purposes only and they are not to be considered in anyway limiting to the scope of the present invention. 30 2017201309 27 Feb 2017 13

The skilled person would easily recognise that changes and modifications can be made with respect to the examples which are still within the scope of the claims. That is, the skilled person will recognise many variations in these examples to cover a wide range of formulas, ingredients, processing, and mixtures to rationally adjust the naturally occurring levels of the compounds of 5 the invention for a variety of applications. B<ample 1 A primary foam iscreated by pumping a 1%solution of sodium caseinate (foaming agent) in water through a Mondomix mixing head. A primary foam overrun in excess of 300% is created. Apinch 10 valve is used to regulate the back pressure in the Mondomix mixing head. Tbe conventional wafer batter ispumped as conventionally done by the batter pump towards the aeration treatment and the batter depositor. Before the batter reaches the batter depositor the primary foam is injected into the flow of the batter. Tbe batter and primary foam then passthrough a static mixer producing a homogeneous aerated batter. Tbe aerated batter then passesthrough the depositor 15 onto the wafer plates.

Fbbust wafers with an effective density in the range 0.08 g/cm3 to 0.16 g/cm3 are successfully baked. 20 B<ample2 A primary foam iscreated by pumping a 1%solution of FTYFQAMA (foaming agent) in water through an in-line Mondomix mixer. Tbe aeration gas is injected into the flow of solution immediately before the mixer. A primary foam overrun in excess of 300% iscreated. Apinch valve is used to regulate the back pressure in the mixer. Tbe conventional wafer batter is pumped as 25 conventionally done by the batter pump towards the aeration treatment and the batter depositor. Before the batter reaches the batter depositor the primary foam is injected into the flow of the batter - the batter and primary foam then passthrough a static mixer producing a homogeneous aerated batter. Tbe aerated batter then passesthrough the depositor onto the wafer plates. 30

Fbbust wafers with an effective density in the range 0.08 g/cm3 to 0.16 g/cm3 are successfully baked. 2017201309 27 Feb 2017 14

Example 3

Conventional Method 1:

It is known that adding extrawater to a wafer batter mix will reduce the effective density of a 5 wafer. In the process of baking any wafer from water based batter, when the batter is heated the water turns to steam, the steam forms bubbles in the mix and these bubbles then form the cells in the wafer structure. The more water there is in a batter, the more steam isgenerated, and the steam generates more bubbles^cells in the final wafer resulting in the batter having a reduced effective density. This method can make wafers with an effective density down to around 0.18 10 g/cm3 that are robust enough to be processed.

Example 4

Conventional method 2:

In order to reduce the effective density of a wafer it is known to add baking powder to a wafer 15 batter. Asthe baking powder is heated in the presence of water, gas ischemically generated that forms bubbles in the batter. These bubbles form the cellular structure in the wafer. Adding more baking powder increases the amount of gas generated, and hence reduces the final effective density of the wafer. However, there is a limit to the amount of baking powder that can be added, as an excess of baking powder leads to a distinct off flavour in the wafer. This leads to the same 20 effective density than by using Conventional method 1 but causes off-flavours in the wafer above 0.6%of batter recipe.

Claims

Qaims

1. A method for the production of a wafer, the method comprises the steps of: (i) providing a batter mix comprising at least flour and water; (ii) subjecting the batter mix to an aeration treatment obtaining an aerated batter mix; (iii) optionally subjecting the aerated batter mix to mixing; (iv) feeding the mixed and aerated batter mix to a heated baking surface through a batter depositor; and (v) baking the mixed and aerated batter mix to obtain a wafer; wherein the aeration treatment in step (ii) isdown-stream from any direct pumping of the method.
2. A method according to claim 1, wherein there is no direct pumping of the batter mix after the batter mix has been subjected to the aeration treatment in step (ii).
3. A method according to any one of claims 1 or 2, wherein the aeration treatment isjust before the batter reachesthe batter depositor or the aeration treatment form part of the batter deposition.
4. A method according to any one of claims 1-3, wherein the aeration treatment involves preparation of a primary foam followed by injection of the foam into the batter mix.
5. A method according to claim 4, wherein the primary foam is prepared by pumping a foaming agent and water through a Mondomix mixing head.
6. A method according to claim 5, wherein the foaming agent is selected from the group consisting of a protein containing milk composition, such as sodium caseinate or HYFQAMA, wheat proteins, albumens and cellulose.
7. A method according to any one of claims4-6, wherein the primary foam hasafoam overrun above 200% such as above 300% e.g. above 400%
8. An apparatusfor the production of awafer which comprises: (i) a storage vessel comprising a batter mix; (ii) an aeration device responsible for an aeration treatment; (iii) a batter feed pump for providing the batter mix from the storage vessel to the aeration device; (iv) a batter depositor for depositing the aerated batter mix onto a heated baking surface.
9. An apparatus according to claim 8, wherein the apparatus further comprises an in-line mixing device.
10. An apparatus according to claim 9, wherein the in-line mixing device is located down-stream from the aeration device.
11. An apparatus according to any one of claims 8-10, wherein the apparatus further comprises a storage vessel for further batter ingredients.
12. An apparatus according to any one of daims8-11, wherein the apparatus comprises a dosing pump for feeding the further ingredientsto the batter mix or the aerated batter mix.
13. An apparatus according to any one of claims 8-12, wherein the aeration device comprises a Mondomix mixing head.
14. Awafer obtainable by a method according to any one of claims 1-7.
15. A wafer having: (i) a breakage force of at least 1N; (ii) an effective density of at most 0.16g/cm3when measured a 20°G