Crackers

Abstract

A process of manufacturing crackers, in which flour 12 and a freeze-dried vegetarian ingredient 10 are mixed 14. The mixture is passed through an extruder 18, then dried 22 and fried 24 to produce the

Description

This invention relates to crackers, i.e. food crackers. THE INVENTION One aspect of the invention consists in a process of manufacturing crackers, in which a flour and a freeze-dried vegetarian ingredient are mixed and the mixture is passed through an extruder, then dried and fried to produce the crackers. Many recipes are known to the present inventor for producing crackers, comprising flour and a vegetarian ingredient (i.e. one containing no animal product), e.g. banana crackers, or other fruit, vegetable or cereal crackers, but these are complicated, intended to be handmade, and / or not consistent in the quality of crackers produced, or their texture, taste or keeping properties. The inventor had researched to find a cracker that should preferably be easy to make, and lend itself to industrial production, with a consistent result of high quality texture, taste and also keeping ability so as to have lasting crispness with maximum and lasting flavour. It is known to the inventor to produce banana crackers from a macerated mixture of mashed banana and tapioca flour that is then fried, but these failed to have the required qualities; and this method is not part of the present invention. In his search for a consistent, high-quality product which could be stored for an extended period without losing quality, he hit upon a freeze-dried banana-family ingredient. He combined this with tapioca flour and extrusion, the freeze-drying retains the flavours, smells and nutritional content. The extrusion alters the internal microstructure of the mix, and hence substantially improves the outcome, especially as to texture, including crunchiness, when it is cooked. He hit upon this idea of starting from freeze-dried bananas, because as an ingredient they could be produced with consistent quality and maintain this over an extended storage period. He has also tried, freeze-dried, a number of other ingredients of the banana family Musaceae, in order to obtain related taste and other qualities, including particularly plantain, but also other edible members of this family. These include various members of the genus Musa, including the scarlet banana (Musa coccinea), the pink banana (Musa velutina) and the Fe'i banana, and also members of the genus Ensete, including the snow banana (Ensete glaucum) and the so-called false banana (Ensete ventricosum). He has also tried successfully a large number of banana cultivars. The inventor later extended his researches to other vegetarian ingredients, namely, fruits, vegetables and cereals, looking particularly for suitable taste and other properties. He found that a process, as in the macerated example mentioned above, in which the ingredient is initially macerated to a soggy, high moisture content pulp containing substantially all the moisture that is to be in the final product, did not give as good a taste as he wanted. This also caused disruption (at this too early stage) of a substantial proportion of the plant cells, which the fruit or vegetable ingredient comprises, leading to a loss of texture and taste in the final product. He therefore eschewed this method of attempting to retain flavour and instead used freeze-drying, a method which, he realised, could quickly dry the ingredient before it was stored, or used to make the crackers, because it is a high-speed drying process that he found not to impair the integrity of the plant cells of the ingredient while moist and to retain substantially the whole of the flavour of the original ingredient. The freeze-drying is so effective (to give a high quality texture and flavour in the final product, due to e.g. preserving the microstructure, i.e. the cell structure, and flavour) that he much prefers to use it in spite of much higher cost than the macerating method. After his mixing, he can rehydrate, the small amount he may find necessary, with substantially no loss of flavour. Further, the final step of frying adds some fat content and substantially zero moisture, both of which the present inventor requires for improved taste and crunchiness, (and improved storability of the finished product,) even though it is quite an expensive step. The inventor's preferred process, in order to obtain a consistent quality of product, includes the step of extrusion. The final product's texture, e.g. crunchiness, requires expansion of the product. This expansion could be done either as the product exits the extruder, known as direct expansion, as used in the macerating method, or as part of the texture improvement due to the step of frying, which expansion is known as indirect expansion, as with the present embodiments; but, e.g. due to expense, no process would include both. The inventor prefers to do it during the step of frying because this gives better consistency, uniformity of product, improved texture and the required taste. It is to be noted that the inventor includes the step of extrusion, which provides a consistent quality of product and lends itself to additional processing (e.g. heating and cooking) in the extruder, and could then provide direct expansion, as just mentioned though not part of the present invention. However, in a method known to the inventor, not part of the present invention, there is provided a step of vacuum cooking, used also to provide expansion via the reduced vacuum pressure (as well as rapid dehydration), so that it would be redundant and too expensive to add to this a step of extrusion. The inventor also looked at flours. He researched a number of different ingredients in the nature of flour, and found that one of them was especially suitable to combine with the banana ingredient, namely tapioca. Reasons for choosing tapioca included that it (like other flours mentioned herein) is practically tasteless when cooked and also that it provides suitable crispness for the finished product. The tapioca is derived from cassava. It is largely starch and has bread- (or biscuit-) related qualities, while being low in saturated fat and sodium and having no dietary fibre. It combines well (in order to produce suitable crackers) with the banana-family ingredient, especially when the latter is comminuted. He then extended his research to other flours, some being more particularly suitable to other said ingredients, e.g having one or more of the properties similar to those just described of tapioca and banana. It is to be noted that the production of a flour or flour variant or other starch powder (e.g. for baking or even as the starchy component for the present embodiments) would not make use of freeze-drying since it is very expensive. The main purpose of the flour of the present embodiments is to provide starch, e.g. to help form the microstructure of the final product rather than its taste. Accordingly, the flour used in the present embodiments would comprise at least 60% starch (w / w when dry, e.g. not grass seed flour), possibly up to substantially 70% or 80%, (or even up to substantially 90% or even 100%, though these would not normally be used); and would provide little or no flavour which, instead, would be provided mostly or substantially entirely by said ingredient, apart from any flavour added after the frying. By way of example, if banana is used both for the flour and for the said ingredient, it is to be noted that the banana flour uses essentially the starch component of the banana (with much-reduced banana taste), while the freeze-dried said ingredient includes more of the banana (and, so, substantially more of the banana-taste), to provide the majority of the banana taste of the final product. The proportion of freeze-dried banana used ranges from substantially 20% upwards, preferably substantially 35% to 40%, preferably not above substantially 40% since the texture then starts to become chewy rather than crunchy. It is to be noted that crunchiness often depends upon the level of sugar in the freeze-dried ingredient and also tends to increase with increasing proportion of the flour used. Again, as exemplified below, the product may comprise substantially up to 80% of the almost tasteless tapioca flour, with the remainder (e.g. substantially 20% or more) being of the freeze-dried banana ingredient. In any case, the proportions will always depend upon what taste and texture are wanted for the final product. All proportional quantities given herein are weight-in-weight. Quantities, e.g. time and / or temperature, could be varied in a manner consequent upon experimentation, e.g. which would be obvious to a food technician. For example, it will be appreciated that figures given herein will need to be varied according to choice of flour and said ingredient and possibly other factors that will affect the texture and taste, by experimenting. For example, for banana flour, the flour-making process may take away substantially one-third to two-thirds of the banana taste.) However, for the flour materials: tapioca, cornflour and potato flour, one takes the immediate skin of their source materials, as well as the starch, if one wants to obtain their taste. For the freeze-dried cereals: corn, sorghum, millet and wheat, one takes the whole of each seed, i.e. fleshy starch plus skin, to give taste. The flour is preferably one which has been dried in a process which does not retain substantially the whole of its taste. This, for example, applies more particularly to a strongtasting flour such as cornflour, for those cases in which the inventor wishes the flour substantially not to impart its taste to the finished cracker, whether strongly or even noticeably. For various reasons, including taste, texture or other effect on or in the final product, the inventor may prefer to use a farinaceous flour, or a banana-family flour or again any flour that comprises one or more chosen from the group comprising tapioca or cassava flour, cornflour, potato flour, banana flour, plantain flour, sorghum flour, millet flour, wheat flour and rice flour. The said ingredient is preferably one which has been freeze-dried in a process which retains substantially the whole of its taste and its microstructure. Said ingredient is preferably in a comminuted form, e.g. a powder form for mixing into said mixture. Said ingredient may comprise a fleshy part of a vegetable or fruit. Said ingredient is preferably plantain or banana but may comprise any one or more edible members of the banana-family Musaceae. If said ingredient comprises a cereal, this can include the skin of the grain (which may contribute substantially to the taste of the finished product) but not the husk. Said ingredient may comprise any one or more chosen from the group comprising tapioca or cassava, banana, plantain, beetroot, butternut squash, honeydew melon, jackfruit, papaya, pumpkin, potato, sweet potato, swede, turnip, yam, corn, sorghum, millet, wheat and rice. This refers to the edible part of each of these, and usually the fleshy part. The various possible combinations of the flours and ingredients mentioned above have been tried and from each of them there has been produced a taste and texture better than any other known to the inventor. Embodiments of the invention may comprise any one or more of the following further steps: • water is added to said mixture in the extruder; • said mixture is part-cooked in the extruder; • the extruded mixture is cut into pellets (which will eventually become the crackers); • the extruded mixture is cut into pellets and then air-dried; • the extruded mixture is air-dried and then fried; • external flavouring is added to the mixture after it has been fried; • the frying is done to a degree which enhances the taste and crunchiness of the product. The ranges of times, temperatures, quantities, and rates of feed, and the order of drying and frying vary from one to another of said groups of flour and ingredient, as well as from one possible pair of flour and said ingredient to another, so that they will vary according to the choice of flour and said ingredient. The air-drying involves drying the product by exposing it to warm air, passing it through a warm chamber, and / or putting it in (or passing it through) a warm oven, for a set amount of time, e.g. half an hour to 2 hours, preferably substantially one hour, at a temperature of preferably between 30° C and 40° C. Other aspects of the invention consist in a cracker as claimed in claim 19 or 20. Thus, there may be provided a process of manufacturing crackers, in which a preferably farinaceous flour and a freeze-dried vegetarian ingredient are mixed and the mixture is passed through an extruder, then dried and fried to produce the crackers. Said flour may comprise one or more chosen from the group comprising tapioca or cassava flour, cornflour, potato flour, banana flour, plantain flour, sorghum flour, millet flour, wheat flour and rice flour. Said ingredient may comprise a fleshy part of a vegetable or fruit, a banana-family member, a cereal and / or one or more chosen from the group comprising tapioca or cassava, banana, plantain, beetroot, butternut squash, honeydew melon, jackfruit, papaya, pumpkin, potato, sweet potato, swede, turnip, yam, corn, sorghum, millet, wheat and rice. Water may be added to said mixture in the extruder and said mixture may be part-cooked in the extruder. The extruded mixture is preferably air-dried and / or fried; and external flavouring may be added to the mixture after it has been fried. The frying is preferably done to a degree which enhances the taste and crunchiness of the product. The invention extends to a cracker produced by any such process and to a cracker produced from a flour and a freeze-dried vegetarian ingredient which have been mixed, and the mixture then passed through an extruder then dried and fried. In one preferred embodiment, the process comprises the steps of providing a freeze-dried banana family ingredient and tapioca flour, mixing these and processing the mixture. More particularly: 1. using a freeze-dried banana-family ingredient, more preferably in a comminuted form, e.g. powder, 2. mixing this with tapioca flour, 3. part-cooking and extruding the mix and cutting the extrudate into pellets, 4. aerating (air-drying) the pellets in a low-temperature region, e.g. within the range 40° C to 50° C 5. frying the pellets, 6. flavouring the pellets, which are then the final product crackers. The range of quantities is 60-65% tapioca flour and 35-40% banana flour by weight. The process provides consistency of the cracker product and improvement of taste and texture and more efficiency in manufacture thereof. Part of the processing includes passing the mixture through an extruder. A small amount (up to substantially a third of the weight of the flour plus said ingredient, or even of the total mixture including the water) of water is added in the extruder. (In an example given below, water is added at a rate of 514 g per hour for a mixture throughput of 1700 g per hour.) There is heating in the extruder. In an example, the extrusion is in the form of a strip coming through a die having an outlet hole of substantially 3 to 4 cm width and a thickness of substantially 2 to 3 mm, the strip expanding after the die to substantially 3.5 to 4.5 cm width by substantially 3 to 5 mm thickness, being cut by a cutter at the extruder outlet into pellets having a length of substantially 3 to 10 cm, preferably substantially 3 to 5 cm. In the extruder, the product is heated to substantially 50 to 60° C. The extruder may have in the region of its outlet a manipulator to provide some degree of starch retrogradation. The pellets are transported on a conveyor belt from the extruder, via a drying and aerating area, e.g. for 5 to 10 minutes, to, and through, a fryer, preferably frying them in rape seed oil. The frying is preferably done at temperatures within the range of substantially 100 to 190° C, preferably 170 to 190° C (e.g. around all substantially at 180° C) and for a period of substantially 40 to 60 seconds. After the fryer, the conveyor passes the fried pellets through a flavouring station to provide flavour on the outside of them. An advantage of this, e.g. over using an initially-flavoured mix, is that the flavour does not contaminate the oil in the fryer (which then could not be used for a different flavour), so that this oil can be used continuously, or even reused, and especially can be used to produce successive batches of crackers having different flavours. The conveyor also allows the pellets to cool and dry (of oil), possibly in specialised stations to facilitate these steps. A manual check is then done. Packing is then automatic. Various processes can be used, comprising the steps: 1. Provide freeze-dried, said (e.g. banana-family) ingredient 2. Mix the materials (the flour and said freeze-dried ingredient) 3. Extrude (and part cook) and cut 4. Aerate (dry) the product in a low temperature area (preferably on a conveyor belt) 5. Fry The extruding is used to sheer the microstructure (cells) of the product and therefore is better than a process which uses moulding and steaming in step 3 just above. The inventor prefers not to combine banana and plantain, because they have different tastes. The freeze-drying of the said ingredient does not affect the crispness of the product, but affects the taste. The freeze-drying preserves the (cell) structure of the ingredient during storage so that, when you add water, the ingredient is restored almost to its original state. The freeze-drying is done on the said ingredient, e.g. banana or plantain, not on the (e.g. tapioca) flour. Preferably, substantially the following ranges of proportions are to be used: 50-60% tapioca and 50-40% freeze-dried banana or plantain powder. Preferably, no other ingredients will be added except that flavourings will be added to the (otherwise) finished product. The inventor has considered various aspects of the processing. In order to eliminate moisture and achieve maximum crispiness, he prefers, just before frying, step 4, described just above, to sun-drying or drying in an oven. This aeration (drying) also has the advantages that it is quicker, more hygienic and more suitable to an industrial process than sun-drying or drying in an oven. The crackers produced do not need to be fried by the purchaser and remain crisp if stored in an airtight container for up to 3 months without needing preservatives. Plantain / banana crackers / crunchies produced by embodiments of this invention differ from such products already known to the inventor in that, while they sometimes have a very similar taste, they have a much crunchier texture and a more uniform taste across crackers / crunchies. The process of manufacturing may comprise any of the following steps, as appropriate:- 1. Plantain or banana is peeled and the skin is discarded. 2. The flesh is sliced and then quickly frozen 3. The frozen slices are then dried very rapidly (freeze-drying) 4. The slices are ground to get the powder, this is the freeze-dried powder 5. The freeze-dried plantain or banana powder is mixed with tapioca flour 6. The mix is then passed through an extruder (a machine); at this stage water is added and the mixture is kneaded. 7. The mixed dough is passed through a die, where it is cut into pellets as it passes through the die. 8. The pellets are left to dry out, usually relatively gently, and then fried to form crackers or crunchies. The numbers or ranges required at different times during the manufacturing process of e.g. the plantain crunchies can be substantially as in the table that follows. These are from a series of tests carried out in a laboratory. Dimensions of the rectangular die opening: 25mm X 1mm Screw: Twin conveyor screw with 2 kneading elements each Speed of the screw: 160rpm Speed of the Feeder (feeding into the extruder): 8 rpm (of a feeding screw in the feeder) Dosing of water into the extruder: 514g / hr Air-drying Time: 24 hrs at room temperature in a preliminary trial. (This step was replaced in a production trial by passing the pellets through an aerating oven at substantially 50 °C. In some examples, 45 minutes to 1 hr at 40° C to 50° C.) Temperature of the screw:- Zonel 32°C Zone2 50°C Zone3 70°C 5 Zone4 80°C These heating zones are defined by length. The length of travel of the mixture through the extruder including the die head is about 1000 mm. The length of each heating zone is about 200 mm. Pressure in the screw 87psi 10 Frying time 30-40 seconds Frying temperature 190 °C The throughput of the mixture through the extruder is approximately 1.7Kg / h (1700gm / hr). Reference will now be made by way of further example to the accompanying drawings, in which: 15 Figure 1 is a schematic process flow diagram for the above-described examples of processes and apparatus; Figure 2 is a schematic side view, partly broken away, of an extruder used in the process; and Figure 3 is a schematic process flow diagram showing steps within the extruder. Referring to the drawings, identical references in the same Figure or different Figures refer to the same item or items that are identical or similar or have similar functions. Referring more particularly to Figure 1, freeze-dried plantain powder ingredient 10 is fed to a mixer together with tapioca flour 12 where they are mixed in a step 14 and fed together with water 16 to an extruder 18 where the mix is kneaded and part cooked, from whence the extruded product is cut in step 20 and then aerated (dried) in step 22 (in the aforementioned aerating oven) to remove moisture, following which the aerated product is fried in vegetable oil in step 24 after which flavouring 26 is added so that the fried product is cooled and flavoured 28 and finally packaged in step 30. Referring more particularly to Figure 2, the materials 10, 12 are fed through a feeding system 32 to a step 14 mixer which may simply be part of a mixing hopper 34 of extruder 18 (operated by gear, motor and bearing 36). The mix is fed by screw 38 through extruder 18 to die 40, following which it undergoes the downstream processing 42 (i.e. steps 22 to 30). Referring more particularly to Figure 3, raw materials 10, 12 are fed into extruder 18 via a feeding system 32 of a mixing hopper 34 followed by the liquid 16, usually water, through mouth 17 of hopper 34, and then in turn through heating zones 1, 2, 3 and 4 (mentioned above), referenced respectively 44, 46, 48 and 50, through to die 40 and then cutter 52, the material being progressed in the direction of arrow 54 by screw 38. The flour and freeze-dried ingredient must be thoroughly mixed, either before going into the hopper or certainly before going into the extruder. The water is added at the beginning of the extrusion process. It will be apparent to one skilled in the art, that features of the different embodiments disclosed herein may be omitted, selected, combined or exchanged and the invention is considered to extend to any new and inventive combination thus formed. Where a preference or particularisation is stated, there is implied the possibility of its negative, i.e. a case in which that preference or particularisation is absent. Many variations of the invention and embodiments hereinbefore described will be apparent to people skilled in the art and all such variations are to be considered as falling within the scope of the invention.

Claims

1. A process of manufacturing crackers, in which a flour and a freeze-dried vegetarian ingredient are mixed and the mixture is passed through an extruder, then dried and fried to produce the crackers.

2. A process as claimed in claim 1, in which said flour has been dried in a process which does not retain substantially the whole of its taste.

3. A process as claimed in any preceding claim, in which said flour comprises a farinaceous flour.

4. A process as claimed in any preceding claim, in which said flour comprises a banana-family flour.

5. A process as claimed in any preceding claim, in which said flour comprises one or more chosen from the group comprising tapioca or cassava flour, com flour, potato flour, banana flour, plantain flour, sorghum flour, millet flour, wheat flour and rice flour.

6. A process as claimed in any preceding claim, in which said ingredient has been freeze-dried in a process which retains substantially the whole of its taste and its microstructure.

7. A process as claimed in any preceding claim, in which said ingredient is in comminuted form for mixing into said mixture.

8. A process as claimed in any preceding claim, in which said ingredient comprises a fleshy part of a vegetable or fruit.

9. A process as claimed in any preceding claim, in which said ingredient comprises a bananafamily member.

10. A process as claimed in any preceding claim, in which said ingredient comprises a cereal.

11. A process as claimed in any preceding claim, in which said ingredient comprises one or more chosen from the group comprising tapioca or cassava, banana, plantain, beetroot, butternut squash, honeydew melon, jackfruit, papaya, pumpkin, potato, sweet potato, swede, turnip, yam, com, sorghum, millet, wheat and rice.

12. A process as claimed in any preceding claim, in which water is added to said mixture in the extruder.

13. A process as claimed in any preceding claim, in which said mixture is part-cooked in the extruder.

14. A process as claimed in any preceding claim, in which the extruded mixture is cut into pellets.

15. A process as claimed in any preceding claim, in which the extruded mixture is air-dried.

16. A process as claimed in any preceding claim, in which the extruded mixture is cut into pellets and then air-dried.

17. A process as claimed in any preceding claim, in which the extruded mixture is air-dried and then fried.

18. A process as claimed in any preceding claim, in which external flavouring is added to the mixture after it has been fried.

19. A process as claimed in any preceding claim, in which the frying is done to a degree which enhances the taste and crunchiness of the product.

20. A cracker produced from a flour and a freeze-dried vegetarian ingredient which have been mixed, and the mixture then passed through an extruder then dried and fried.

21. A cracker as claimed in claim 20, produced by a process as claimed in any one of claims 9 19.30 03 26Amendents to the claims have been filed as follows:NEW CLAIMS1. A process of manufacturing crackers, comprising:a. mixing a flour with a freeze-dried vegetarian ingredient,i. wherein the freeze-derived ingredient has been freeze-dried so as to retain substantially the whole of its flavour and cellular microstructure,ii. and is in comminuted form,b. passing the mixture through an extruder in which water is added and the mixture is kneaded and part-cooked,i. wherein the extrusion alters said structure,c. and subsequently drying and frying the extruded mixture to produce crackers, wherein the freeze-derived ingredient provides substantially entirely the flavour of the cracker and the flour provides starch for forming the microstructure of the final product.

2. A process as claimed in claim 1, wherein the flour comprises at least 60% starch by weight and provides substantially no flavour to the final product.

3. A process as claimed in any preceding claim, wherein the flour is a farinaceous flour selected from the group comprising: tapioca or cassava flour, com flour, potato flour, banana flour, plantain flour, sorghum flour, millet flour, wheat flour and rice flour.

4. A process as claimed in any preceding claim, wherein the freeze-dried ingredient comprises a member of the banana family (Musaceae).

5. A process as claimed in any preceding claim, wherein the freeze-dried ingredient is in powder form.

6. A process as claimed in any preceding claim, which includes the step of freeze-drying and wherein the freeze-drying preserves the cellular structure of the ingredient such that, upon addition of water as part of the process, the ingredient is rehydrated with substantially no loss of flavour.

7. A process as claimed in any preceding claim, wherein the freeze-dried ingredient is so used as to avoid disruption of its cells prior to extrusion.

8. A process as claimed in any preceding claim, wherein the extrusion step shears the cellular microstructure of the mixture to improve texture and crunchiness of the final product.

9. A process as claimed in any preceding claim, wherein the extruded mixture is air-dried at a temperature of 30°C to 40°C prior to frying.

10. A process as claimed in any preceding claim, wherein frying is carried out at 100°C to 190°C to enhance crunchiness and taste.

11. A process as claimed in any preceding claim, wherein the mixture comprises:a. 50"65% flour, andb. 3 5 "5 0% freeze-dried ingredient, by weight.30 03 2612. A process as claimed in any preceding claim, comprising:a. mixing freeze-dried banana or plantain powder with tapioca flour,b. extruding, cutting into pellets, air-drying, frying, and optionally flavouring.

13. A process as claimed in any preceding claim, in which water is added to said mixture in the extruder.

14. A process as claimed in any preceding claim, in which said mixture is part-cooked in the extruder.

15. A process as claimed in any preceding claim, in which the extruded mixture is cut into pellets.

16. A process as claimed in any preceding claim, in which the extruded mixture is air-dried.

17. A process as claimed in any preceding claim, in which the extruded mixture is cut into pellets and then air-dried.

18. A process as claimed in any preceding claim, in which the extruded mixture is air-dried and then fried.

19. A process as claimed in any preceding claim, in which external flavouring is added to the mixture after it has been fried.

20. A cracker produced by a process as claimed in any preceding claim, wherein the cracker comprises:-a. a starch-based matrix derived from the flour, andb. a freeze-dried vegetarian ingredient providing substantially the flavour of the cracker, the cracker having an improved crunchiness and uniform texture resulting from preservation and modification of the cellular-microstructure of the ingredient during extrusion and frying.

21. A cracker as claimed in claim 20, wherein the ingredient comprises a banana-family member.s

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