Patent Application
20170251681
The present disclosure relates to a healthy biscuit product which contains high levels of protein and fibers, sufficient to promote a feeling of fullness or satiety and to permit nutritional claims, such as being a “source” or “rich in” protein and/or fibers. In particular, the disclosure provides a dough and a method for forming the dough which allows for an increased content of fiber and protein, without compromising the handling characteristics of the dough.
Proteins are an important nutritional component of a healthy well balanced diet. During digestion, proteins are broken down into smaller polypeptide chains and amino acids which are then used to generate new proteins. Some amino acids are called “essential”, because they cannot be biosynthesized by the body and have to be found in food. Proteins are available from meat, fish and eggs, as well as from whole grains, pulses, legumes, soy, dry fruits, nuts and seeds. It is known in the art that protein is useful for increasing the satiety provided by food products.
It is also known that fiber is an important nutritional component of a healthy well balanced diet. Dietary fibers are carbohydrates with a degree of polymerization larger than 3 that are neither absorbed nor digested in the small intestine. They form a broad class of materials, from oligosaccharides to complex plant cell walls. Dietary fibres are usually separated in 3 main types, depending on their functional properties:
Dietary fibers have many physiological benefits, among which are lowering of blood glucose response, reducing cholesterol, improving transit and regularity, and promoting satiety. Fiber intake in many countries is below recommended levels, so there is a desire to increase the fiber content of food products.
WO2010046492 discusses the benefits of increasing the fiber content of biscuits and discusses a number of issues associated with increasing the fiber content. In particular, the inclusion of fibers can bind strongly to the water in the dough and affect the hydration of the dough.
EP2255663 discusses the use of a combination of denatured protein and fiber to increase the satiety experienced from a biscuit or cracker product.
U.S. Pat. No. 6,610,347 discloses fiber enriched compositions produced by a process involving cooking a calcium caseinate and whey protein slurry in an evaporator and spray-drying the mixture. The method relies upon physical interaction between the protein and the fibers to create a layer which limits swelling of the fiber particles.
US2005058759 discloses a protein enhanced, low carbohydrate snack food having from about 10% to about 50% fat material, from about 5% to about 40% sugar substitute, from about 5% to about 50% protein material, and methods of making and using the same.
CN102783610 discloses a meal replacing grain rod and preparation method for meal replacing grain rod.
Accordingly, there is a desire to provide an improved product which provides increased levels of protein and fibers, provides an increased satiety, tackles the problems associated with the prior art, or at least provides a useful commercial alternative thereto.
According to a first aspect there is provided a biscuit dough comprising:
The present invention will now be further described. In the following passages different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.
By the term “biscuit”, it is meant any baked cereal products, with a low moisture content (less than 5%, preferably less than 4%) and a crispy texture, made from a dough or a batter, which includes the commonly known biscuits, cookies, crackers, wafers and baked granola bars, preferably biscuits, cookies, crackers and wafers.
By the term “biscuit dough” it is meant a dough suitable for forming a biscuit when baked. Doughs are well known in the art and are typically formed from a mixture of dry ingredients and added water to make a workable mixture.
The dough comprises protein in an amount of at least 8 wt % by weight of the final biscuit. That is, the dough includes sufficient protein such that, when baked to form a biscuit, the final biscuit includes at least 8 wt % of protein. As will be appreciated, the baking process leads to a loss of water from the dough. Accordingly, a level of 8 wt % protein in the biscuit is achieved by a slightly lower amount of protein by weight of the moist dough. The protein levels of the biscuit correlate to the level of protein in the dry ingredients.
The dough comprises fibers in an amount of from 5 to 20 wt % by weight of the final biscuit. That is, the dough includes fiber such that, when baked to form a biscuit, the final biscuit includes at least 5 to 20 wt % of fiber. As will be appreciated, the baking process leads to a loss of water from the dough. Accordingly, a level of 5 wt % fiber in the biscuit is achieved by a slightly lower amount of fiber by weight of the moist dough. The fiber levels of the biscuit correlate to the level of fiber in the dry ingredients. Preferably the fiber is in an amount of from 10 to 16 wt % by weight of the final biscuit.
The dough comprises native whey protein in an amount of at least 0.5 wt % by weight of the dough. Since the whey protein may be affected by the baking process, the level of native whey protein is characterised by weight of the dough. The dough includes the added water sufficient to make the dough workable.
By the term “native” it is meant that the protein has not been denatured. Methods of denaturing proteins are well known in the field of baking and include thermal treatments, often with steam or hot water. A native whey protein is one which retains the form and structure that it has in the original dairy source material. The native whey protein may be a spray-dried whey protein or have been subjected to a low temperature treatment, provided that the protein remains substantially in its native form.
The dough comprises fiber which comprises viscous soluble fibers and/or insoluble fibers. As discussed above, dietary fibres are usually separated in three main types, depending on their functional properties. The dough preferably comprises insoluble fibres, such as resistant starches and plant cell wall polysaccharides found in grains, vegetable and fruits; and/or viscous soluble fibers, which are high molar mass polysaccharides with an extended conformation in solution, such as soluble beta-glucan from oat, guar gums and other viscous gums. Preferably the dough does not comprise any (preferably less than 2 wt % by weight of the biscuit, more preferably less than 1 wt %, more preferably essential none) non-viscous soluble fibers, which are mostly oligosaccharides, such as fructo-oligosaccharides, resistant dextrins and polydextrose.
The inventors have found that it is difficult to incorporate additional fibers into biscuit doughs. This is especially the case for insoluble fibers and viscous soluble fibers. Without wishing to be bound by theory, it is considered that because of their high affinity for water, fibers tend to absorb the water added during mixing, preventing or delaying the formation of the dough. More water is required to form processable dough, especially with viscous soluble fibers. The dough texture also tends to evolve during resting time, becoming drier and harder because of water migration from the continuous phase to the fiber particles, which can only be addressed with further water.
While increased dough hydration can be used to make a dough more malleable, the inventors have found that the increased hydration has a number of disadvantages when preparing biscuits. In particular, the increase in dough hydration can make dough texture develop, requiring increased baking times and/or temperatures, which are costly and can lead to quality issues, such as excess of coloration, burnt off-tastes and checking. Increasing dough hydration also leads to enhanced starch gelatinization during baking, which increases glycaemic response, and thus lowers the nutritional interest of such protein-fiber enriched biscuits.
The inventors have further found that the same problems arise for proteins as for fibers. Accordingly, for a combination of dietary fibers with proteins there is such an increase in the required dough hydration that the dough pieces cannot be handled anymore during the process. This prevents reaching levels that may be efficient for nutrition (“rich in” proteins and/or fibers) or satiety claims.
As noted above, fibers and proteins are known to increase dough stiffness significantly. While one way to address this is to increase the hydration of the dough, the inventors were surprised to find that a very different behaviour was observed with native whey protein, in particular native whey protein concentrates and isolates. The inventors found that this native whey protein could be used to allow the dough hydration to be reduced, or when used in combination with fibers, it allowed the moisture content to be maintained or reduced while increasing the fiber content of the dough.
Examples of native whey proteins include native whey protein concentrate (WPC) or isolates (WPI), for instance Prolacta 80™ from Lactalis Ingredients or native whey protein isolate WPI 894™ from Fonterra. Without wishing to be bound by theory, one possible explanation is the high solubility of these proteins that readily dissolve in the added water during dough mixing, hence increasing the volume of the continuous phase (water and sugars) rather than forming partially hydrated swollen particles that would be part of the dispersed phase. The findings indicate that such highly soluble and non-viscous proteins (being native and non-aggregated) can be considered as dough plasticizer, similar to water and sugars.
Preferably the insoluble fibers comprise one or more of brans from cereal grains and/or fibers from fruits or vegetables. Preferably the cereal grains are selected from wheat, oat, barley and rye, or combinations of two or more thereof. Preferably the viscous soluble fibers comprise one or more of guar gum, tara gum, locust bean gum, fenugreek, xanthan, pectins, alginates, beta-glucans, glucomannans, konjac and psyllium.
Preferably the viscous soluble fibers and/or insoluble fibers comprise from 3 to 15 wt % by weight of the dough. Preferably, these fibers form from 5 to 10 wt % of the dough. These fibers are important to provide a feeling of fullness, satiation and/or satiety and other dietary benefits such as flattening blood glucose response, lowering blood cholesterol and improving regularity. Moreover, these fibers allow the production of a dough with desirable levels of hydration, despite high levels of fiber and protein in the biscuit. Preferably the fiber comprises less than 2 wt % non-viscous soluble fibers by weight of the final biscuit, preferably less than 2 wt %. These fibers are easy to incorporate in biscuit dough, but their fermentation in the colon can generate some discomfort and limit gastro-intestinal tolerance, especially in the case of a high fiber product, containing already insoluble and/or soluble viscous fibers.
Preferably the dough comprises added water in an amount of less than 25 wt % by weight of the dough, more preferably less than 20 wt %, and most preferably less than 15 wt % by weight of the dough. Preferably the dough comprises added water in an amount of at least 12 wt %.
It is important to note that the water in the dough is the water added to form the dough. Trace amounts of moisture may be present, trapped in the ingredients used, and this is not included when considering the dough hydration, unless specified (see Examples 3 and 4)
Preferably the protein is in an amount of up to 25 wt % by weight of the final biscuit, preferably about 14 wt % by weight of the final biscuit. Preferably the protein is present in an amount of from 10 to 20 wt %, more preferably in an amount of from 12 to 16 wt % of the final biscuit. These levels of protein provide an improvement of the nutritional profile of the biscuits and/or advantageous satiation or satiety from the final biscuit.
The dough preferably contains at least 0.5 wt % native whey proteins. The inventors found that there is an optimal dosage of native whey protein that corrects the effect of dietary fibers or other proteins and “restores” dough machinability. Preferably the native whey protein is in an amount of from 1 to 11 wt % by weight of the dough. Below this critical dosage, the dough is too dry, too hard and not cohesive enough so that biscuit dough pieces do not resist transfer to the oven and break apart. More preferably the dough contains from 1.5 to 8 wt % of native whey protein, more preferably from 2 to 6 wt %.
Preferably the protein in the dough is below 25 wt %, more preferably below 20 wt %. Above this critical dosage, the dough becomes too sticky and dough pieces tend to deform and be incomplete after forming.
Preferably the dough comprises sugar in an amount of from 5 to 25 wt %, preferably from 10 to 20 wt %, by weight of the final biscuit. Preferably the dough comprises fat in an amount of from 5 to 25 wt %, preferably from 10 to 20 wt %, by weight of the final biscuit. Preferably the dough has a ratio by weight of sugar to fat of about 1:1. These levels of fat and sugar help to provide a cohesive dough, but also one which is nutritionally beneficial. Preferably the dough comprises inclusions, preferably oat flakes, or any fragments of grains (such as cereals and pseudo-cereals), ancient grains (e.g. quinoa) or pulses (pea, chickpea, etc . . . ) under the form of flakes, grits of crisps. These inclusions bring a combination of fibers and proteins, an appealing texture contrast and a natural/wholesome aspect to the finished product. Other inclusions such as chocolate drops or dried fruit pieces can also be incorporated.
Preferably the dough comprises flour and oat flakes in a ratio of flour to flakes of 1.5:1.
According to a further aspect there is provided a biscuit obtainable by shaping and baking the biscuit dough described herein. Shaping techniques, including rotary moulding, are well known in the art. Temperatures and conditions required for baking the dough composition to form a biscuit are well known in the art.
Preferably the biscuit has a water activity of less than 0.4. The water activity (Aw) of a product is a notion which is well known in the food industry field. This value measures the availability of water in a sample. In most cases, this water activity is not proportional to the water content of the product. Methods for measuring Aw of a product are known to the person skilled in the art. For example, it can be measured with an Aqualab CX-2 or series 3, or a Novasina. All Aw values indicated hereafter are measured at 25±0.1° C.
According to a further aspect there is provided a method for forming the biscuit dough described herein, the method comprising:
In a preferred example, the mixing process comprises:
The proteins including native whey protein can be added either at step b) or step d). The criterion for duration of each phase is the texture of the dough and its homogeneity, assessed by the operator. This process is unusual because it requires pre-dissolving the sugars. If this is not done, the inventors found that native whey proteins solubilize before sugars, enter in competition for water and this prevents the solubilisation of sugars, giving a stiffer dough which is more difficult to process Preferably the sugar solution comprises all of the added sugar and water in the dough, and optionally further comprises ammonium bicarbonate.
This process of mixing used is not recommended in the prior art: the impact of the order of incorporation of the ingredients has been studied by Manohar and Rao (R. S. Manohar, P. H. Rao, Eur. Food Res. Technol. 1999, 210, 43-48) on short dough biscuits. The authors conclude that the most efficient method to reduce dough hydration is to make a “creaming” (i.e. dissolve sugars and disperse fat in water to form a water-based emulsion) and add the rest of the powders (including flour) after. This allowed to obtain dough with low hydration (16%), low elastic recovery (indicative of low gluten development), low cohesiveness, low adhesiveness and gave after baking the crispier biscuits. In contrast, the mixing method used herein, referred to by Manohar and Rao as “creaming followed by water and flour addition” was the least effective: dough has a significantly higher hydration (25%), elastic recovery, cohesiveness, adhesiveness and gave after baking biscuits with excessively higher thickness, porous crumb and hard texture. Therefore, the prior art does not recommend to favour the contact of flour with water.
Dissolving the sugars usually leads to an increase in the spread of the cookies and a correlated reduction in their thickness. Furthermore, it can give hard products which lack crispiness, as the fully dissolved sugars form a hard “glass” after baking instead of staying in the form of sugar crystals which act like “breakage points” and promote a crispy texture. It is however required herein, since the whey proteins otherwise prevents sugar dissolution by competing with sugars against the added water. This would not be expected based on conventional baking techniques.
Advantageously, the inventors have found that the method described herein allows during the mixing stage for the dough hydration to be comparable to standard dough (i.e. without any enrichment in fibers or proteins), at the forming stage for the yield and dough stability to be comparable to standard dough (without enrichment), and for the stack height of final biscuits to be similar to control biscuits (without enrichment).
Preferably the liquid fat ingredient is provided with one or more emulsifiers.
Preferably the flour is provided with other dry powder ingredients, preferably salt, and/or sodium bicarbonate and/or sodium acid pyrophosphate.
According to a further aspect there is provided a method for forming a biscuit from the dough of described herein, the method comprising the steps of:
Preferably the step of shaping the dough is a step of rotary moulding. Rotary moulding is particularly advantageous for shaping doughs with low moisture levels and containing inclusions. Alternatively forming techniques such as, laminating, sheeting or low shear extrusion can also be used, provided appropriate corrections in the mixing and dough hydration, well known by the man of the art.
Preferably the method further comprises a step of applying a glazing, coating and/or filling to the biscuit.
Preferably the method further comprises a step of packaging the cookie.
The product may optionally further comprise a coating. The filling may be provided within a biscuit product, between two or more biscuit products or as an overlying coating layer around at least an outer portion of a biscuit. That is, when there is only one biscuit, the filling part can be deposited wholly onto one surface thereof or partially on each surface. The filling part can also be deposited inside the biscuit. When there are two or more biscuits, the filling part may be layered between two biscuits to form a so-called sandwich biscuit.
A glazing can also be added before baking to control the final colour of the biscuit and give a shiny appearance.
According to a preferred aspect of the disclosure there is provided a biscuit dough comprising:
The inventors have found that by combining specific dosage of native whey proteins with other proteins or texturing dietary fibers the dough processability can be maintained. This was surprising because the prior art recommends to denature and aggregate whey proteins as the best way to minimize their impact on dough processing. The prior art also often reports a shrinkage of such products when enriched in whey protein concentrates, while the inventors found the opposite for native whey proteins.
In particular, the inventors have found that a whey protein derived directly from cold milk (i.e. not previously heated) without heat-treatment has a preserved gelling ability. Without this protein, a high fiber dough is powdery and cannot be processed. The inventors have found an optimum amount of whey protein provides an ideally processable dough. Below this amount the dough is powdery, whereas above this amount the dough becomes too sticky for rotary-molding technology.
The present invention provides a number of particular advantages. These include a high fiber-high protein biscuits for satiety. Improvements for wholegrain products whereby the limit of dough hydration and dough stability may be improved. The whey protein also allows for a restored stack height and crispiness. In addition it is possible to provide high volume cookies with lots of inclusions (such as dry fruits).
Without wishing to be bound by theory, the method of the present invention does not involve any particular physical interaction between the protein and fibers. It is instead the protein dissolution which creates a reduction in the water holding capacity.
According to a further aspect there is provided a biscuit comprising:
The disclosure will be described in relation to the non-limiting figures:
The disclosure will now be described with relation to the following non-limiting examples:
In this example, rotary moulded dough was enriched in proteins and hydration level required to obtain dough suitable for rotary moulding was monitored.
Proteins were added in order to reach about 23 of total proteins in biscuits after baking. Different proteins were used:
Protein ingredients were added in replacement of flour in a control recipe. The amount of dry flour and proteins was kept equal to 1340 g. When added, proteins were kept constant on a dry basis and equal to 340 g. Other ingredients (fats, sugars, etc . . . ) were kept constant in the dough. Water content of the dough was adjusted in order to have suitable dough for subsequent forming. The recipes of the dough enriched in proteins are described in Table 1.
The following manufacturing process was used. A VMI Phebus mixer of 10 kg capacity equipped with a flat beater paddle and operating at speeds ranging from 30 to 120 rpm was used.
Incorporation of the ingredients was done manually in the following steps:
At the end of mixing, dough temperature was of 26.5±1.5° C. After mixing, dough was directly shaped (without resting time) using a lab-scale rotary moulding machine in order to assess dough technological behaviour.
The amount of added water and dough moisture required to obtain process able dough are reported in Table 2 and shown in
It was found that with all proteins except native whey protein concentrates (WPC), dough hydration had to be increased significantly, up to almost 3 fold vs control dough. Surprisingly, upon addition of WPC, it was possible to produce process able dough with a lower hydration than the control dough while maintaining dough machinability. Other dairy proteins such as sodium caseinate and milk protein concentrates (although containing 20% of WPC on dry basis), had a very different behaviour than native WPC.
Blending native whey proteins with other proteins, such as pea protein concentrates (PPC) and milk protein concentrates (MPC), gave a dough with an intermediate hydration requirement. For instance with a blend of 25% WPC and 75% PPC, it was required to add 18% water, which is between the value of 10.2% for WPC only and 23.5% for PPC only.
Summary of Example 1
A biscuit dough was enriched in proteins in order to reach about 23% of total proteins in biscuits after baking. Water content of the dough was adjusted in order to have suitable dough for forming using rotary moulding. Different protein ingredients were used: sodium caseinate, native whey protein concentrate, milk protein concentrate and pea protein concentrate. With all proteins except native WPC, it was required to increase dough hydration significantly, up to almost 3 fold vs control dough. Surprisingly, upon addition of WPC, it was possible to reduce dough hydration (vs control dough). Blending WPC with other proteins required intermediate values (i.e. between that of WPC and that of the other protein) of added water to have workable dough.
In this example, dough was enriched in both fibers and proteins and hydration level required to obtain dough suitable for rotary moulding was monitored.
Viscous soluble fibers, guar gum (GG) and oat bran (OB) were added in order to reach 12 of total dietary fibers (TDF) in biscuits after baking, including those from flour and flakes. The protein ingredients were pea protein concentrate (PPC) and native whey protein concentrate (WPC). Proteins were added in order to reach 16% of total protein in biscuits, including those from flour and flakes.
Fibers and proteins were added in replacement of flour and flakes, keeping a constant flour/flakes ratio of 1.5:1. Sugar and fat contents were adjusted to remain at a constant value of 15% (each) in the biscuit after baking. Table 3 shows the dough recipes.
The following manufacturing process was used. A Hobart mixer of 20 kg capacity equipped with a flat beater paddle and operating at 3 speeds, from 1 (low) to 3 (high) was used.
Incorporation of the ingredients was done manually as follows:
At the end of mixing, the dough temperature was of 26±2° C. After mixing, the dough was shaped using a pilot plant rotary moulding, in order to assess dough technological behaviour.
The amount of added water and dough moisture required to obtain process able dough are reported in Table 4 and shown in
As demonstrated in this example, increasing fibres (guar gum GG or oat bran OB) or pea protein contents (PPC) required increasing dough hydration significantly. 13. However, adding native WPC to GG and OB-enriched dough allowed reducing significantly dough hydration down to 10% for guar gum-biscuit (F9) and 14% for oat bran (F12). These dough hydration values are close to that of the Control dough, which is unexpected for dough containing 12% fibers and 16% protein.
Blending PPC and WPC again showed an intermediate behaviour compared to PPC and WPC alone. Biscuit F10 is both enriched in guar gum (12%) and proteins (16%). The ratio of WPC to PPC is 1:4 and dough hydration requirement is 16.0%.
This example demonstrates that adding WPC, preferentially to any other source of proteins reduces the hydration requirement of fiber and protein-rich doughs while maintaining dough machinability.
Adding dietary fibers led to a significant shrinkage of the biscuits, especially significant on the stack height. This shrinkage was even increased upon addition of pea protein concentrates (PPC). However, using native whey protein concentrates WPC in combination with fibers allowed to obtain the dimensions close to control biscuit (especially length and width) or even increased, especially the stack height. The increased stack height observed for the biscuits containing fibers and WPC could offer the opportunity to decrease the use of the baking powders, especially BCA, in order to match precisely the dimensions of the control biscuit. This type of correction is known by the person skilled in the art.
Note that the use of WPC slightly increased the spread of the biscuits (higher length, higher width) as well as the stack height. This is an unusual behaviour: most ingredients that increase spreading (like sugars, fats) also decrease biscuit thickness.
The sensory properties of the biscuits of Example 2 were analysed by a trained Panel of 12 volunteers. Texture attributes of the biscuits are reported in Table 6.
On some attributes, such as friability or melting, the addition of WPC counter-balanced the impact of dietary fibers, so that the fibers-WPC biscuits were closer to the control than the fiber-enriched biscuits. The use of WPC also resulted in an increase in crispiness, lightness vs the control product, which can be considered as positive for the mouthfeel.
Summary of Example 2
Biscuit dough was enriched in viscous soluble fibers (guar gum and oat bran) and proteins (pea protein concentrates and native whey protein concentrates) in order to reach 12% total dietary fibers and 16% of total proteins in biscuits after baking. Water content of the dough was adjusted in order to have suitable dough for forming using rotary moulding.
It was found that incorporating viscous soluble fibers required a significant increase in the dough hydration. This requirement further increased when pea protein concentrates were added to the fiber-enriched dough. However, it was counter-balanced by addition of native whey protein concentrate. Dough containing both viscous soluble fibers and native whey protein concentrates could be made at the same dough hydration as the control (without protein or fiber addition) and had the same technological behaviour. This greatly facilitates the production of high fibers and high protein biscuits.
In this example, the dosage of native whey protein concentrates (WPC) was adapted in a fiber-enriched dough such as to obtain processable dough with the same hydration as the control dough. In this case, the total dough moisture is considered, i.e. added water as well as the residual moisture from the raw materials.
Several dietary fibers were used and incorporated in order to reach 10% of 20% of total dietary fibers (including those from flour and flakes) in the finished product:
The amount of whey proteins (WPC) was progressively increased, in replacement of flour and flakes, keeping a constant flour/flakes ratio of 1.5:1. Sugar and fat contents were adjusted to remain at a constant value of 15% each in the biscuit after baking.
Table 7 describes the dough formula with wheat bran and WPC enrichment for a TDF target of 20%.
The manufacturing process described in Example 2 was used. At the end of mixing, the dough temperature was of 29±2° C.
During and just after mixing, the dough “texture” and aspect were evaluated in order to assess dough machinability.
The same methodology was applied for all fibers described above, at 10% and 20% total dietary fiber content.
Table 8 summarizes the amount of WPC that needs to be added to obtain workable dough with the same hydration as the control one. This amount depends on the type of dietary fibers but as shown in table 8, whatever the amount and type of dietary fibers incorporated, there is a dosage of WPC that allows having the same hydration as the control dough.
Summary of Example 3
Biscuit dough was enriched in both fibers (soluble viscous or insoluble such as guar gum, oat bran and wheat bran) and native whey proteins. Fibers were added such as to obtain a total fibers content in the final biscuit of 10% and 20%. Native whey protein concentrates were incorporated in increasing amount, from 0.5% to 12%, and the impact of this addition on dough process ability was monitored for the different fibers.
It was found that for any given dough (fiber content and type), there was an optimum dosage of native whey protein concentrate at which it was possible to obtain a dough with the same hydration and process ability as the control dough. Below this dosage of WPC, the dough was too dry and not suitable for rotary moulding. Above this dosage of WPC, the dough was too sticky and cohesive, making it again not suitable for rotary moulding.
In this example, amount of fibers, native whey concentrate and added water were fixed. The different dough generated were evaluated at pilot scale for their technological behaviour and especially yield and processing stability.
Dough formulas were enriched in both fibers and native whey protein concentrates. Same dietary fibers as in the Example 3 (wheat bran, guar gum and oat bran) were incorporated in biscuit dough in order to reach 10% of 20% of total dietary fibers (including those from flour and flakes) in the finished product. Native whey protein concentrates were incorporated at relatively limited amount (vs other Examples) in replacement of flour and flakes, keeping a constant flour/flakes ratio of 1.5. Sugar and fat contents were adjusted to remain at a constant value of 15% each in the biscuit after baking. Total dough moisture was set at fixed values (20%, 22.5%, 25% and 28%) and processing ability was evaluated. The recipes of the dough enrich in WPC and oat bran, guar gum and wheat bran are respectively given in Tables 9, 10, 11.
The following manufacturing process was used. Processing parameters (mixing, rotation speed of the rotary moulding machine, baking profile, etc . . . ) were kept constant for all experiments.
Mixing was performed in a Perkins Guitlard horizontal drum mixer of 20 kg capacity and operating at speeds ranging from low to high. Incorporation of the ingredients was done manually as follows:
At the end of mixing, the dough temperature was of 23±1° C. The dough was then left at rest for 15 minutes, after which it was formed using a pilot scale R-Tech 300 mm rotary moulding machine. Each recipe was run over a 50 minutes period, during which the rotary moulding was operating during 2 minutes, followed by a stop of 5 minutes. This allowed a batch of 15 kg of dough to be run during almost 1 hour, which is the order of magnitude of industrial processing.
The biscuit were then baked using a Imaforni continuous oven and collected for analysis. The baked biscuits were then collected for each of the 2 minutes run period and analysed with respect to their aspect. The number-based proportion of acceptable product (without noticeable defects) vs unacceptable products (broken or incomplete products) was referred to as the yield (Equation below). The evolution of this proportion of acceptable products vs processing time was taken as an indicator of dough stability.
For each of these experiments, the following parameters were extracted from the curves:
The average yield and stability time for the different formulas of Example 4 are given in Table 12 (formula with 10% dietary fibers in the finished product) and 13 (formula with 20% dietary fibers in the finished product). NB: OB=oat bran; GG=guar gum; WB=wheat bran; WPC=native whey protein concentrates.
Addition of insoluble or viscous dietary fibers dramatically decreases dough stability, as seen by the drop in average yield and stability time. This situation cannot completely be solved by increasing dough hydration, which is the typical correction that the man of the art would perform: for instance formula F22, enriched in oat bran, had a poorer performance than the control formula (F17) in spite of a 25% increase in moisture content (i.e. 25% for F22 vs 20% for F17).
Adding native whey protein concentrates allows correcting the impact of fiber enrichment. Both the average yield and dough stability are improved. For instance, adding native WPC to formula F22 (to give formula F21) gave dough of same performance as the Control dough and only a limited dough hydration increase (+12.5%).
Adding native WPC hence appears as a way to restore technological performance of high fibers dough, while contribution to obtain high fibers and high protein healthy biscuits (with limited sugar and fat content).
The biscuits dimensions are reported in Table 14.
Adding dietary fibers reduces the stack height of baked biscuit, which is a well-known issue in the prior art.
Adding WPC together with dietary fibers allow to counter-balance this negative effect of fibers and restore a stack height value close to that of the control biscuit (same height or less than 6% difference).
Summary of Example 4
Biscuit dough was enriched in both fibers (soluble viscous or insoluble such as guar gum, oat bran and wheat bran) and native whey proteins, similar to Example 3. Fibers were added such as to obtain a total fibers content in the final biscuit of 10% and 20%. Native whey protein concentrates were incorporated in increasing amount, from 0% to 9.3%. Dough moisture was set at fixed values (20%, 22.5%, 25% and 28%) and processing ability of the different dough was evaluated with a focus on stability and yield. For this purpose, a pilot scale rotary moulding line was operated by sequence of 2 minutes, followed by a stand-by of 5 minutes, during a total time of 50 minutes (resting time of 8 minutes followed by 6 running periods). The yield was evaluated visually for the different sequences by monitoring the proportion of well-designed biscuits vs incomplete or broken ones after baking. As a reference, the control dough (without protein and fibers added) had a moisture content of 22.5% and a good yield (>75%).
It was found that insoluble or viscous soluble dietary fibers strongly decrease dough stability and yield. Increasing hydration partly restored processing ability but usually for a limited period of time, after which yield dramatically dropped. This situation was counter-balanced by adding native whey protein concentrates, at a dosage depending on fiber type and content. The yield improvement obtained by adding this protein was higher than that obtained by increasing hydration alone.
Incorporation of dietary fibers also reduced the stack height of baked biscuit, which is well known in the prior art. Adding native whey protein concentrates together with dietary fibers allowed to counter-balance this negative effect of fibers and restore a stack height value close or even above that of the control biscuit.
Although preferred embodiments of the invention have been described herein in detail, it will be understood by those skilled in the art that variations may be made thereto without departing from the scope of the invention or of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 14184662.6 | Sep 2014 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2015/070819 | 9/11/2015 | WO | 00 |
