Methods to reduce asparagine in whole grain flour

Abstract

This invention describes a method for reducing the asparagine content of whole grain flour used in the production of baked goods. The method involves treating the whole grain by conditioning it in an aqueous solution of an asparagine-reducing composition to concentrate and localize asparaginase activity in the bran and germ of the whole grain. In one method, the asparagine-reducing composition may include an asparaginase. In another method, the asparagine-reducing composition may include a yeast strain capable of degrading asparagine. Conditioning with the asparagine-reducing composition reduces the asparagine content in the whole grain by at least about 25%, thereby producing whole grain flour with an asparagine content not exceeding about 250 ppm. Baked goods with reduced asparagine and acrylamide content are also described, comprising whole grain flour obtained by treating the whole grain with the asparagine-reducing composition during conditioning.

Description

Technical Field

[0001] The methods described herein generally involve reducing the asparagine content of whole grain flour, thereby reducing the acrylamide concentration of whole grain flour during thermal processing, and reducing the acrylamide concentration of thermally processed products containing whole grain flour. Background Technology

[0002] Acrylamide is a chemical that can form in some foods during high-temperature cooking. For example, acrylamide can be formed at temperatures above approximately 120°C via the Maillard reaction pathway through a non-enzymatic browning reaction between reducing sugars and amino acids, such as asparagine. Therefore, acrylamide formation can be a problem during the production of baked goods and other baked products. Furthermore, asparagine is primarily found in the bran and germ of whole grains, rather than in the endosperm. Therefore, whole grain flour can have up to two-thirds higher asparagine levels compared to white flour, which is primarily formed from the endosperm, thus increasing the likelihood of acrylamide formation in baked goods containing whole grain flour. Summary of the Invention

[0003] This article describes a method for reducing the asparagine content of whole grain flour by treating whole grains with an asparagine-reducing composition during tempering. In some methods, the asparagine-reducing composition includes an asparaginase. In other methods, the asparagine-reducing composition includes yeast having or otherwise promoting asparaginase activity. Advantageously, in both methods, the asparaginase activity is localized and concentrated in the bran and germ of the whole grain, thereby maximizing the asparaginase activity during and after treatment.

[0004] In a method for reducing asparagine by including an asparaginase in a composition, the enzymatic treatment comprises conditioning the whole grain in an aqueous solution of the asparaginase, which serves as a conditioning medium. The aqueous solution of the asparaginase may be contained in the conditioning mixture at about 5% to about 15% by weight. The asparaginase in the conditioning medium hydrolyzes the asparagine in the whole grain into aspartic acid and ammonia, thereby reducing the amount of asparagine in the whole grain that can be used to form acrylamide during baking.

[0005] In some methods, the asparaginase can have an asparaginase activity of approximately 3500 ASNU per gram of enzyme. In some methods, the asparaginase can be derived from Aspergillus oryzae. During conditioning, the concentration of the asparaginase in the conditioning medium can be at least approximately 2550 ppm, for example, approximately 4550 ppm.

[0006] In methods of comprising asparagine-reducing compositions including yeast, the yeast is included in a conditioning medium in an amount, for example, from about 0.1% to about 4.0% by weight of the conditioning mixture, and in some methods, it is included in a conditioning medium in an amount from about 0.2% to about 2.0% by weight of the conditioning mixture. Particularly useful asparagine-reducing yeast strains include baker's yeast (i.e., brewer's yeast (Saccharomyces cerevisiae)), and more specifically, non-GMO baker's yeast having asparaginase activity and / or being able to degrade asparagine in an aqueous medium.

[0007] In some methods, the conditioning process using the asparagine-reducing composition can be carried out at ambient temperature, and in other methods, at a temperature of about 10°C to about 60°C, for example, at about 50°C. In some methods, the conditioning process can last for a duration of about 4 hours to about 8 hours. In other methods, the conditioning process can last for a longer duration, for example, up to 24 hours. In some methods, the conditioning process can last even longer, for example, up to 32 hours, particularly when germination of the grain is desired. Depending on the specific asparagine-reducing composition used, the conditioning process can generally be carried out under conditions that effectively hydrate the whole grain to a suitable moisture content and promote high levels of asparaginase activity. For example, in some methods, the final moisture content of the conditioned grain can be about 14% by weight to about 26% by weight. In some methods, the conditioned whole grain can be dried to obtain a moisture content suitable for milling, for example, about 10% by weight to about 16% by weight.

[0008] After conditioning, the whole grain can be milled, for example, to obtain bran and germ fractions and endosperm fractions. The bran and germ fractions can optionally undergo stabilization treatment to reduce lipase, thereby forming stabilized bran and germ fractions. The stabilized bran and germ fractions can then be combined with the endosperm fraction to form stabilized whole grain flour with reduced asparagine levels.

[0009] Whole grain flour obtained by conditioning whole grains with a composition that reduces asparagine typically has an asparagine content of no more than about 250 ppm. In some methods, conditioning with a composition that reduces asparagine can reduce the asparagine content of whole grain flour by at least about 25% compared to untreated whole grain flour.

[0010] In some methods, at least a portion of the asparagine-reducing composition can be absorbed by the whole grain during conditioning, primarily by the bran and germ of the whole grain. In this way, asparaginase activity is concentrated in the fraction of the whole grain containing the highest amount of asparagine. At least a portion of the asparagine-reducing composition can also remain in the whole grain flour after milling, thereby allowing the asparagine in the whole grain to continue to hydrolyze after processing and, in some cases, during storage and / or dough formation.

[0011] The resulting whole grain flour is particularly suitable for the production of baked goods. Asparagine concentration has been shown to be a major limiting factor for acrylamide formation in whole grains. Therefore, reducing the asparagine content of whole grain flour using the methods described herein can significantly reduce the unwanted acrylamide formation in baked goods containing treated whole grain flour. For example, in some methods, baked goods produced using the asparagine-reduced whole grain flour described herein can exhibit a significant reduction of at least about 20% and at most about 50% or more in acrylamide compared to baked goods produced using untreated whole grain flour. Attached Figure Description

[0012] Figure 1 This is a process flow diagram of an exemplary method for reducing the asparagine content in whole grain flour used in the production of baked goods.

[0013] Figure 2 This is a graph illustrating the reduction in asparagine after conditioning with yeast that reduces asparagine. Detailed Implementation

[0014] The term "whole grain" encompasses the whole grain before any processing, such as as wheat berries or kernels. As noted in the FDA's draft guidance of February 15, 2006, and as used herein, the term "whole grain" includes grains consisting of the whole, milled, broken, or hulled fruit of the grain, whose major components—starch endosperm, germ, and bran—are present in the same relative proportions as they are present in whole grains. According to the FDA, such grains can include barley, buckwheat, dry wheat, corn, millet, flees, rye, oats, sorghum, wheat, and wild rice.

[0015] As used herein, the term “milling” encompasses the steps of rolling, crushing, screening, and sorting whole grains to separate them into their constituent parts, which may also result in some reduction in the particle size of the constituent parts.

[0016] As used herein, the term “grinding” encompasses any method involving reducing particle size, including but not limited to causing particles to collide with each other or mechanically reducing particle size.

[0017] As used in this article, the term "conditioning" refers to the process of adding water to wheat before milling to toughen the bran and soften the endosperm of the whole grain, thereby improving flour separation efficiency.

[0018] Unless otherwise specified, all percentages used herein are by weight and based on filler composition.

[0019] This article describes a method for reducing the asparagine content of whole grain flour used in the production of baked goods and baked goods with reduced acrylamide content, which contains whole grain flour with reduced asparagine content. One technique for reducing acrylamide in baked goods involves adding asparaginase as an ingredient during dough formation to hydrolyze asparagine in the grain into aspartic acid (or aspartic acid) and ammonia, thereby reducing the amount of asparagine available for acrylamide formation during heating. However, the high moisture content of the dough and the presence of various dough ingredients can undesirably inhibit or otherwise dilute the enzymatic activity of asparaginase. This article describes an excellent method for reducing asparagine in whole grain flour at lower moisture content to maximize, localize, and concentrate enzyme activity in the high-asparagine fraction of the whole grain, resulting in a greater reduction in asparagine in the resulting whole grain flour and thus a lower acrylamide content in baked goods containing asparagine-reduced whole grain flour.

[0020] Figure 1 An exemplary method for reducing the asparagine content in whole grain flour used in the production of baked goods is shown. Asparagine—an amino acid precursor of acrylamide—is present in high amounts in whole grains, primarily in the bran and germ. As a result of treating whole grains with an asparagine-reducing composition during conditioning as described herein, asparaginase activity can be maximized and the asparagine content of whole grains (and flour produced therefrom) can be significantly reduced, thereby mitigating the formation of undesirable acrylamide in baked goods containing whole grain flour derived from the treated whole grains.

[0021] It is believed that treating whole grains with an asparaginase-reducing composition during conditioning has several advantages compared to, for example, using asparaginase as an ingredient during dough formation or otherwise treating grains after milling. For instance, during dough formation, asparaginase activity may be limited by other ingredients such as, for example, salt, sugar, and leavening agents. Enzyme activity may also be reduced or otherwise diluted due to the high moisture content (e.g., up to 50%) during dough formation. Furthermore, since the outer bran and germ of whole grains contain higher amounts of asparaginase compared to the inner endosperm, treating whole grains with an asparaginase-reducing composition during conditioning (i.e., before milling) can localize and concentrate asparaginase activity in the fraction of the whole grain with the highest asparaginase content. Moreover, enzymatic treatment of whole grains during conditioning (i.e., early in the process for producing baked goods) allows for maximization of asparaginase activity during and after treatment. For example, since at least a portion of the composition that reduces asparagine can be absorbed in the bran and germ of whole grains during conditioning, asparaginase degradation can continue after conditioning, milling, and even after the whole grain flour is added to the dough, resulting in a significant reduction in asparaginase activity, and acrylamide formation is further reduced through extension.

[0022] like Figure 1 As shown, treating whole grains with a composition that reduces asparagine during conditioning may include mixing the composition 102 that reduces asparagine with water 104 to obtain a substantially aqueous conditioning medium, and mixing the conditioning medium with whole grains 106.

[0023] Whole grains primarily consist of endosperm, bran, and germ, in decreasing proportions. In whole wheat grains, based on the weight of the whole grain, for example at approximately 13% wt% field moisture, the endosperm or starch comprises about 83% wt%, the bran about 14.5% wt%, and the germ about 2.5% wt%. The endosperm contains starch and has a lower protein content than the germ and bran. The asparagine content in the endosperm is also lower than in the bran and germ portions. Bran (pericarp or outer shell) is the mature ovary wall, located below the cuticle, and includes all the outer cell layers down to the seed coat. Bran is rich in non-starch polysaccharides such as cellulose and pentosans. The asparagine content in bran or pericarp is also higher than in the endosperm. Due to its high fiber content, bran or pericarp tends to be very hard and imparts a dry, gritty texture, especially when present in large grain sizes. Bran or pericarp also contains most of the grain's lipases and lipoxygenases, which require stabilization. As the degree of grinding or milling increases, the bran particle size approaches that of starch, making it more difficult to separate bran and starch. Furthermore, starch damage tends to increase due to greater mechanical energy input, the abrasiveness of bran compared to endosperm, and the breakage of starch granules. Additionally, mechanically damaged starch tends to gelatinize more easily. The germ is characterized by its high fat content. The germ is also rich in crude protein, sugar, and ash.

[0024] While not limited to this, the whole grains used herein may be selected from, for example, soft / soft and soft / hard wheat berries. In some methods, these whole grains may include white or red wheat berries, hard wheat berries, soft wheat berries, winter wheat berries, spring wheat berries, durum wheat berries, or combinations thereof. Examples of other whole grains that may be processed according to various or certain embodiments or aspects include, for example, oats, corn, rice, wild rice, rye, barley, buckwheat, bulgar, millet, spelt wheat, sorghum, etc., and mixtures of whole grains. Whole grains may be in the form of, for example, whole grain kernels, flakes, etc. Preferably, the whole grains are not cooked before conditioning.

[0025] Refer again Figure 1 Whole grains 106 undergo conditioning 108 in a conditioning medium containing water 104 and a composition 102 containing reduced asparagine.

[0026] In some methods, the composition for reducing asparagine may include an asparaginase composition. The asparaginase composition may include any asparaginase or a combination thereof, and the asparaginase may be derived from any suitable source. In some methods, the asparaginase may be in powder or granular form. In other methods, the asparaginase may be in liquid form. In some methods, the asparaginase may be derived from *Aspergillus oryzae*. In some methods, the asparaginase may have an asparaginase activity of approximately 3500 ASNU per gram of enzyme. One non-limiting exemplary asparaginase that may be used in the embodiments described herein comprises an asparaginase manufactured by Novozymes A / S of Bagswald, Denmark. 3500 BG. Another non-limiting exemplary asparaginase that may be used in the embodiments described herein includes one manufactured by Novozymes AB of Bagswald, Denmark. L. The concentration of asparaginase during conditioning is typically at least about 2550 ppm, and in some methods it can be about 4550 ppm.

[0027] In other embodiments, the asparagine-reducing composition may comprise a yeast strain having asparaginase activity. Particularly useful asparagine-reducing yeast strains are baker's yeast (i.e., brewer's yeast), and more specifically, non-GMO baker's yeast having asparaginase activity and / or capable of degrading asparagine in an aqueous medium. One non-limiting exemplary asparagine-reducing yeast that may be used in the embodiments described herein includes Acryleast. TM This is a clean-label bread yeast manufactured by Kerry, Nash, Ireland. The amount of asparagine-reducing yeast included in the conditioning medium can range from about 0.1% by weight to about 4.0% by weight of the conditioning mixture, and in some methods from about 0.2% by weight to about 2.0% by weight of the conditioning mixture.

[0028] In some methods, the conditioning operation 108 can be carried out in a conventional conditioning tank containing conditioning water 104 and whole grain 106, and the asparagine-reducing composition 102 can be added to the water 104 in the conditioning tank. In other embodiments, the asparagine-reducing composition 102 can be premixed with all or part of the conditioning water 104 to obtain an aqueous conditioning medium, which is then added to the conditioning tank to mix with the whole grain 106. In either case, the amount of the conditioning medium containing water 104 and the asparagine-reducing composition 102 is about 5% by weight to about 15% by weight of the conditioning mixture.

[0029] The moisture content of whole grains can be controlled by conditioning them with a composition that reduces asparagine, such that the outer parts of the grain are hydrated or moistened while the inner parts are essentially dry. This treatment avoids or substantially reduces the need to dry the fine fractions obtained from the interior or endosperm of the grain, while moistening the exterior or bran and germ portions for subsequent stabilization treatments if needed or desired. This treatment also localizes and concentrates asparaginase activity in the bran and germ portions of the grain, which contain higher levels of asparagine compared to the endosperm portion.

[0030] The conditioning process for whole grains can be carried out in any suitable container, such as a bath or vat. The conditioning time can range from about 2 hours to up to 32 hours, depending on the specific asparagine-reducing composition used and the desired final moisture content.

[0031] For example, in methods where the asparagine-reducing composition used in the conditioning medium is an asparaginase, the conditioning time can range, for example, from about 4 hours to about 8 hours, to adequately moisten the whole grain and sufficiently reduce its asparagine content. In other methods, the conditioning time can be up to 24 hours. In methods where the asparagine-reducing composition used in the conditioning medium is an asparagine-reducing yeast composition, the conditioning time can range, for example, from about 10 hours to about 32 hours, and in some methods from about 14 hours to about 30 hours. It should be noted that the conditioning time should be suitable for effectively hydrating the whole grain to a suitable moisture content and, based on the specific asparagine-reducing composition used, promote high levels of asparaginase activity.

[0032] In some methods, the whole grain can be conditioned to obtain a moisture content of about 14% to about 26% by weight based on the weight of the whole grain, more preferably about 15% to about 24% by weight, and most preferably about 16% to about 22% by weight in some methods. In methods where the composition for reducing asparagine is yeast, the inventors have found that yeast has particularly high asparaginase activity at a grain moisture content of about 21% by weight.

[0033] As discussed herein, at least a portion of the composition reducing asparagine can be absorbed by the whole grain during conditioning, thereby allowing sustained asparaginase activity after conditioning and milling, during storage, and even during dough formation. Therefore, it is generally preferred to select conditioning time and final moisture content to obtain a moisture content suitable for milling, while also maximizing sustained asparaginase activity after conditioning.

[0034] In some embodiments, the conditioning process using the composition with reduced asparagine can be carried out at a temperature of about 10°C to about 60°C, for example, at about 50°C. Preferably, the conditioning process is carried out without the application of active heating. In some methods, the conditioning process can be carried out at ambient temperature, which may vary based on, for example, environmental factors. However, it is preferred that the conditioning process be carried out at a temperature not exceeding 60°C. The conditioning temperature can also be selected to avoid significant starch gelatinization, protein denaturation, and / or inactivation of asparaginase or yeast.

[0035] In some methods, the conditioning temperature and moisture content can be controlled, as measured by differential scanning calorimetry (DSC), such that starch gelatinization is less than about 25%, preferably less than about 10%, and most preferably less than about 5%. An example of achieving a low degree of starch gelatinization and low degree of starch damage is that, at a peak temperature of about 65°C to about 70°C, the starch melting enthalpy is greater than about 4 J / g, preferably greater than about 5 J / g, based on the weight of starch in the bran and germ fraction, as measured by differential scanning calorimetry (DSC). In an embodiment, at a peak temperature of about 60°C to about 65°C, the bran and germ fraction may have a starch melting enthalpy greater than about 2 J / g, as measured by differential scanning calorimetry (DSC), based on the weight of the bran and germ fraction. Starch gelatinization typically occurs when: a) sufficient water (based on the weight of starch, typically at least about 30% by weight) is added to and mixed with the starch, and b) the temperature of the starch is raised to at least about 80°C (176°F), preferably 100°C (212°F) or higher. The gelatinization temperature depends on the amount of water available to interact with the starch. Generally, the lower the amount of water available, the higher the gelatinization temperature. Gelatinization can be defined as the disintegration (destruction) of the molecular order within starch granules, manifested as irreversible changes in properties such as granule swelling, melting of natural microcrystals, loss of birefringence, and starch dissolution. The initial stage temperature of gelatinization and the temperature range at which gelatinization occurs are influenced by starch concentration, observation method, granule type, and heterogeneity within the observed granule group. Gelatinization is the second stage phenomenon following the first stage of gelatinization in starch dissolution. It involves increased granule swelling, the exudation of molecular components (i.e., amylose, followed by amylopectin) from the granules, and ultimately, complete granule destruction. See Atwell et al., “The Terminology and Methodology Associated With Basic Starch Phenomena,” Cereal Foods World, Vol. 33, No. 3, pp. 306-311 (March 1988).

[0036] Low levels of starch gelatinization and starch damage can be measured by sodium carbonate-water solvent retention power (SRC). SRC can be measured by mixing a sample (such as whole grain flour) containing a component or part of the product by weight (A) (e.g., about 5 g) with a large excess of water or other solvent (such as an aqueous solution of sodium carbonate (e.g., 5% sodium carbonate by weight)) and centrifuging the solvent-powder mixture. The supernatant can then be gently poured off, and the sample can be weighed to obtain the weight (B) of the wetted sample after centrifugation, wherein the SRC value is calculated by the following equation: SRC value = ((BA) / A)) × 100. In some embodiments, asparagine-reduced whole grain flour may have a sodium carbonate-water solvent retention power (SRC) comparable to a control.

[0037] Return to reference Figure 1 After conditioning, whole grains can undergo conventional milling 110 to obtain bran and germ fractions 112 and separated endosperm fractions 114.

[0038] Exemplary milling techniques include milling and / or grinding operations for obtaining bran and germ fractions and endosperm fractions, and for obtaining powders, fractions, and components having particle size distributions such as those disclosed in the following documents: for example, U.S. Patent Application Publications Nos. US2005 / 0136173, US2006 / 0073258, 2007 / 0269579, 2007 / 0292583; U.S. Patents Nos. 7,258,888, 8,133,527, and 8,173,193; and International Patent Application Publication No. WO2007 / 149320. In some embodiments, milling and / or grinding operations may be employed to obtain bran and germ fractions and endosperm fractions, and to obtain powders, fractions, and components having particle size distributions as disclosed in the following documents: U.S. Patent Application Publication No. 2007 / 0292583; U.S. Patent Nos. 8,133,527 and 8,173,193; and International Patent Application Publications Nos. WO 2007 / 149320 and WO 2012 / 148543. The disclosure of each reference identified in this paragraph is incorporated herein by reference in its entirety.

[0039] In some methods, the bran and germ fractions 112 may optionally undergo one or more stabilization treatments 116 (heated or unheated) before being recombined with the endosperm fraction 114 to inactivate or reduce lipase activity. Exemplary stabilization treatments may include, for example, stabilization by treatment with a lipase inhibitor as disclosed in International Patent Publication No. WO 2012 / 142399 and / or stabilization by heating during transport and mixing as disclosed in WO 2014 / 149810 (the disclosures of these references are incorporated herein by reference in their entirety), which may be used in conjunction with the enzymatic conditioning of this application to help reduce wheat flavor and enhance the caramelized flavor of products produced by the methods disclosed therein, provided that the lipase inhibitor stabilization conditions, such as pH, or the lipase inhibitor itself, do not adversely affect the reduction of asparagine caused by the asparaginase conditioning methods described herein.

[0040] Regardless of whether the separated fractions undergo further processing, stabilization, etc., the bran and germ fractions are recombined with the endosperm fraction to form asparagine-reduced whole grain flour. In some embodiments, the bran and germ fractions are derived from the same whole grain as the endosperm fraction. However, in other embodiments, the bran and germ fractions may be combined or blended with endosperm fractions derived from or obtained from different grain sources. However, in each embodiment, the bran and germ fractions, along with the endosperm fraction, are combined or blended to provide an enzymatically treated whole grain flour containing endosperm, bran, and germ in proportions identical or substantially identical to their relative proportions present in the whole grain.

[0041] In some embodiments, the asparagine-reduced whole grain flour can have a particle size distribution of 0% by weight on a 35 (500 micrometer) US standard sieve and less than or equal to about 20% by weight (preferably less than or equal to about 10% by weight or 5% by weight) on a 70 (210 micrometer) US standard sieve. In another embodiment, the asparagine-reduced whole grain flour can have a particle size distribution of up to about 100% by weight passing through a 70 (210 micrometer) US standard sieve. Additionally, the asparagine-reduced whole grain flour can also have a particle size distribution of at least 75% by weight, preferably at least 85% by weight, for example about 90% to about 98% by weight, less than or equal to 149 micrometers and less than or equal to 5% by weight greater than 250 micrometers. In some respects, the bran and germ fractions can have a fine particle size distribution of 0% by weight on a 35 (500 microns) US standard sieve and a particle size distribution of less than or equal to about 20% by weight on a 70 (210 microns) US standard sieve.

[0042] Whole grain flour 118 obtained by conditioning whole grains with the asparagine-reducing composition described herein exhibits excellent reduction in asparagine content. For example, the resulting asparagine-reduced whole grain flour typically has an asparagine content of no more than about 250 ppm. In some methods, the conditioning treatment described herein can reduce the asparagine content of whole grain flour by at least about 25% compared to untreated whole grain flour. In some methods, the reduction in asparagine content compared to untreated whole grain flour can be at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, and in some methods at least about 70%.

[0043] The asparagine-reduced whole grain flour described herein can be packaged, stored stably, and subsequently or immediately used in food production. By adding water and other suitable food ingredients, mixing, shaping, and baking or frying, the asparagine-reduced whole grain flour is ready for further processing into final food products. Dough containing asparagine-reduced whole grain flour can be continuously produced and mechanically processed on a large-scale production basis, such as sheeting, laminating, molding, extruding or co-extruding, and cutting.

[0044] The asparagine-reducing whole grain flour described herein can be used in a variety of food products, and particularly in products that have been cooked, baked, or otherwise heat-treated, and thus are prone to acrylamide production. For example, in some methods, baked goods produced using the asparagine-reducing whole grain flour described herein can exhibit a significant reduction of at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, and in some methods at least about 45%, compared to baked goods produced using untreated whole grain flour. In some methods, the reduction in acrylamide content can be at least about 50% or more compared to baked goods produced using untreated whole grain flour.

[0045] Food products may include starchy food products, pasta products, instant cereals, confectionery, and especially biscuit products. In some embodiments, food products may be baked products or snack foods. Baked products may include cookies, crackers, pizza crusts, tortillas, bread, bagels, pretzels, brownies, muffins, waffles, pastries, cakes, quick-baked bread, sweet rolls, donuts, fruit and cereal bars, tortillas, and semi-baked products. Snack products may include snack slices and extruded or puffed snacks. Food products may be specifically selected from cookies, crackers, and cereal bars. Cookies may be bar products, extruded, co-extruded, sheet and cut, rotary-molded, wire-cut, or sandwich cookies. Examples of producible cookies include sugar wafers, fruit-filled cookies, chocolate chip cookies, sugar cookies, etc. Crackers may be leavened or non-lean crackers, as well as whole-wheat crackers. The baked goods produced can be biscuits, crackers, or cookies with full fat content, or they can be reduced-fat, low-fat, or fat-free products.

[0046] Besides water, ingredients that can be mixed with asparagine-reduced whole grain flour for biscuits, cookies, crackers, and snacks include fortified wheat flour, vegetable shortening, sugar, salt, high-fructose corn syrup, leavening agents, flavorings, and colorings. Fortified wheat flours that can be used include those rich in niacin, reduced iron, thiamine nitrate, and riboflavin. Vegetable shortenings that can be used include those made from partially hydrogenated soybean oil. Leavening agents that can be used include calcium phosphate and baking soda. Colorings that can be used include plant-based colorings such as annatto extract and ginger oil resin.

[0047] In some embodiments, the prepared dough comprises doughs of various combinations including conventional amounts of the aforementioned biscuit, shortbread, cracker, and pastry ingredients. According to some embodiments, all the aforementioned ingredients are uniformly mixed, and the amount of water is controlled to form a dough with the desired consistency. The dough can then be shaped into blocks and baked or fried to produce products with excellent moisture, geometry, appearance, texture, and flavor properties.

[0048] In some methods, based on the weight of the dough (excluding the weight of inclusions), the total amount of powder components, asparagine-reduced whole grain flour, and optional other powders that can be used in baked goods compositions (such as cookies, biscuits, and crackers) can range, for example, from about 20% by weight to about 80% by weight, preferably from about 45% by weight to about 75% by weight. Unless otherwise stated, all weight percentages are based on the total weight of all ingredients forming the dough or formulation, excluding inclusions such as candies or flavored flakes or blocks, nuts, raisins, etc. Therefore, "the weight of the dough" does not include the weight of inclusions, but "the total weight of the dough" includes the weight of inclusions.

[0049] Process-compatible ingredients that can be used to alter the texture of a produced product include sugars such as sucrose, fructose, lactose, glucose, galactose, maltodextrin, corn syrup solids, hydrogenated starch hydrolysates, protein hydrolysates, glucose syrup, and mixtures thereof. Reducing sugars (such as fructose, maltose, lactose, and glucose, or mixtures thereof) can be used to promote browning. Exemplary sources of fructose include invert sugar syrup, high-fructose corn syrup, molasses, brown sugar, maple syrup, and mixtures thereof.

[0050] Texture-enhancing ingredients (such as sugar) can be mixed with other ingredients in solid or crystalline forms (such as crystalline or granulated sucrose, granulated brown sugar, or crystalline fructose) or in liquid forms (such as sucrose syrup or high-fructose corn syrup). In some embodiments, moisture-retaining sugars, such as high-fructose corn syrup, maltose, sorbitol, galactose, corn syrup, glucose syrup, invert sugar syrup, honey, molasses, fructose, lactose, glucose, and mixtures thereof, can be used to enhance the chewiness of baked goods.

[0051] Besides humectants, other non-sugar humectants or aqueous solutions of humectants with lower sweetness compared to sucrose can also be used in dough or batter. For example, glycerol, sugar alcohols (such as mannitol, maltitol, xylitol, and sorbitol), and other polyols can be used as humectants. Other examples of humectants (i.e., polyhydroxy alcohols) include glycols, such as propylene glycol, and hydrogenated glucose syrup. Other humectants include sugar esters, dextrins, hydrogenated starch hydrolysates, and other starch hydrolysates.

[0052] In some implementations, based on the weight of the dough (excluding the weight of the contents), such as the total sugar solids content or texturing component content of the dough produced, can range from 0% by weight to about 50% by weight.

[0053] Sugar solids can be wholly or partially replaced by conventional sugar substitutes or conventional leavening agents (such as polydextrose, whole cellulose, microcrystalline cellulose, mixtures thereof, etc.). Polydextrose is a preferred sugar substitute or leavening agent for the manufacture of low-calorie baked goods. An exemplary amount of replacement may be at least about 25% by weight of the original sugar solids content, for example at least about 40% by weight, preferably about 50% by weight to about 75% by weight.

[0054] In some implementations, the amount of conventional sugar substitutes, conventional leavening agents, or conventional powder substitutes (such as polydextrose) may be from about 10% to about 35% by weight, for example, from about 15% to about 25% by weight, based on the weight of the dough (excluding the weight of the contents).

[0055] The dough should have sufficient moisture content to provide the required consistency so that it can be properly shaped, processed, and cut. The total moisture content of the dough will include any water contained as a separately added ingredient, as well as moisture provided by the flour, moisture from any leavening agents or flour substitutes (such as resistant starch type III components), and moisture from other dough additives contained in the formulation (such as high-fructose corn syrup, invert sugar syrup, or other liquid moisture-retaining agents).

[0056] Oily compositions that can be used to obtain dough and baked goods may include any known shortening or fat blends or compositions (such as butter) suitable for baking applications, and they may contain conventional food-grade emulsifiers. Examples of shortenings or fats that can be used include fractionated, partially hydrogenated, and / or transesterified vegetable oils, lard, marine oils, and mixtures thereof. Edible, low- or low-calorie, partially digestible or indigestible fats, fat substitutes, or synthetic fats, such as sucrose polyesters or triglycerides, which are process-compatible, may also be used. Hard fats and soft fats, or mixtures of shortening and oils, may be used to achieve the desired consistency or melting characteristics in the oily composition. Examples of edible triglycerides that can be used to obtain oily compositions include naturally occurring triglycerides derived from plant sources such as soybean oil, palm kernel oil, palm oil, rapeseed oil, safflower oil, sesame oil, sunflower seed oil, and mixtures thereof. Marine oils and animal fats, such as sardine oil, herring oil, babassu oil, lard, and tallow, may also be used. Synthetic triglycerides and natural triglycerides of fatty acids can also be used to obtain oily compositions. The fatty acids can have a chain length of 8 to 24 carbon atoms. Solid or semi-solid shortenings or fats that are stored at room temperature, for example, from about 75°F to about 95°F, can be used. Preferred oily compositions include soybean oil. In embodiments, based on the weight of the dough, the dough can contain up to about 30% by weight, for example, from about 5% by weight to about 25% by weight, at least one oil or fat.

[0057] Baked goods produced using the asparagine-reduced whole grain flour described herein include calorie-reduced baked goods, which are also reduced-fat, low-fat, or fat-free products. As used herein, a reduced-fat food product is one whose fat content is reduced by at least 25% by weight compared to a standard or regular product. Low-fat products have a fat content of less than or equal to three grams of fat per reference serving or label serving. However, for smaller reference servings (i.e., 30 grams or less or two tablespoons or less), low-fat products have a fat content of less than or equal to 3 grams of fat per 50 grams of product. Fat-free or zero-fat products have a fat content of less than 0.5 grams of fat per reference serving and label serving. For gift crisps, such as savory crisps, the reference serving is 15 grams. For cookies and crisps intended as snacks, the reference serving is 30 grams. Therefore, based on the total weight of the final product, the fat content of a low-fat crisp or cookie will be less than or equal to 3 grams of fat per 50 grams or less than or equal to about 6% fat. Based on the weight of the final product, the fat-free gift crisps will have a fat content of less than 0.5 grams per 15 grams or less than about 3.33%.

[0058] In addition to the above, the dough may also include other additives commonly used in crisp biscuits and cookies. Such additives may include, for example, regular amounts of dairy by-products, eggs or egg by-products, cocoa, vanilla, or other flavorings.

[0059] Suitable protein sources for inclusion in baked goods may be incorporated into the dough used to promote Maillard browning. Protein sources may include defatted milk powder solids, dried or powdered eggs, mixtures thereof, etc. For example, based on the weight of the dough (excluding the weight of its contents), the amount of protein source may be, for example, up to about 5% by weight.

[0060] Based on the weight of the dough (excluding contents), the dough composition may contain up to about 5% by weight of a leavening agent system. Examples of chemical leavening agents or pH adjusters that may be used include alkaline and acidic materials, such as sodium bicarbonate, ammonium bicarbonate, acid calcium phosphate, sodium pyrophosphate, diammonium phosphate, tartaric acid, mixtures thereof, etc. Yeast may be used alone or in combination with chemical leavening agents.

[0061] The dough used may include antimycins or preservatives such as calcium propionate, potassium sorbate, sorbic acid, etc. To ensure microbial storage stability, an exemplary amount may be up to about 1% by weight of the dough (excluding the weight of the contents).

[0062] Emulsifiers can be included in the dough in an effective emulsifying amount. Exemplary emulsifiers that can be used include monoglycerides and diglycerides, polyoxyethylene sorbitan fatty acid esters, lecithin, stearoyl lactate, and mixtures thereof. Exemplary polyoxyethylene sorbitan fatty acid esters that can be used are water-soluble polysorbates such as polyoxyethylene (20) sorbitan monostearate (polysorbate 60), polyoxyethylene (20) sorbitan monooleate (polysorbate 80), and mixtures thereof. Examples of natural lecithin that can be used include those derived from plants such as soybeans, rapeseed, sunflower, or corn, and those derived from animal sources such as egg yolks. Lecithin derived from soybean oil is preferred. Examples of stearoyl lactate are basic stearoyl lactate and alkaline earth stearoyl lactate, such as sodium stearoyl lactate, calcium stearoyl lactate, and mixtures thereof. An exemplary amount of emulsifier that can be used is up to about 3% by weight of the dough (excluding the weight of the contents).

[0063] Dough can be produced using conventional dough mixing techniques and equipment used for producing biscuit, shortbread, and cracker dough.

[0064] Although baking time and temperature will vary depending on different dough or batter recipes, oven type, etc., generally speaking, commercial cookies, brownies and cakes can be baked for about 2.5 minutes to about 15 minutes, and the baking temperature can be from about 250℉ (121℃) to about 600℉ (315℃).

[0065] Baked goods may have a relative vapor pressure (“water activity”) of less than about 0.7, preferably less than about 0.6, to achieve preservative-free microbial storage stability. Based on the weight of the baked goods (excluding contents), cookies, brownies, and cakes typically have a moisture content of less than about 20% by weight, for example, about 2% to about 9% by weight for cookies.

[0066] For example, in some embodiments, dough for producing storage-stable crisps or cookies (such as whole wheat crisps) may contain about 40% to about 65% by weight of whole grain flour, about 15% to about 25% by weight of at least one sugar (such as sucrose), about 5% to about 25% by weight of at least one oil or fat (such as vegetable oil or shortening), about 0% to about 10% by weight of at least one moisture-retaining sugar (such as high fructose corn syrup and honey), about 0% to about 1% by weight of a protein source (such as skim milk powder solids), about 0% to about 1% by weight of a flavoring agent (such as salt), about 0.5% to about 1.5% by weight of a leavening agent (such as ammonium bicarbonate and sodium bicarbonate), and about 8% to about 20% by weight of added water, wherein each weight percentage is based on the weight of the dough, and the weight percentages add up to 100 by weight.

[0067] In embodiments, baked goods containing whole grain flour exhibit reduced acrylamide content due to the reduced asparagine content in the whole grain, which is derived from whole grain treated during conditioning with an asparagine-reducing composition (such as asparaginase or certain yeasts with asparaginase activity as described herein). For example, in some methods, baked goods produced using the asparagine-reducing whole grain flour described herein can exhibit a significant reduction of at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, and in some methods at least about 45%, compared to baked goods produced using untreated whole grain flour. In some methods, the reduction in acrylamide content can be at least about 50% or more compared to baked goods produced using untreated whole grain flour.

[0068] Example 1

[0069] An experiment was conducted to demonstrate that the asparagine content of whole grains treated with an aqueous solution of asparagine during conditioning was significantly reduced compared to whole grains conditioned without asparaginase. Uncooked whole wheat grain samples were conditioned at ambient temperature with the addition of 2% water. The final moisture content of the conditioned whole grains ranged between 9% and 15%. The conditioned whole grains were then milled to obtain whole grain flour.

[0070] Another sample of uncooked whole wheat grains was conditioned with 11% water and 4550 ppm of asparaginase. The conditioning process was carried out at 50°C, and the final moisture content of the conditioned whole grain was between 20% and 26%. The whole grain was then milled to obtain whole grain flour.

[0071] The asparagine content of whole grain flour obtained from untreated whole grains was 292 ppm, while the asparagine content of whole grain flour obtained from whole grains that underwent enzymatic treatment with asparaginase during conditioning was 194 ppm, representing a reduction of more than 30%. This example demonstrates the significant reduction in asparagine content achieved by conditioning whole grains using an aqueous solution of asparaginase as the conditioning medium.

[0072] Example 2

[0073] This example illustrates the reduction of asparagine in whole grain flour obtained by conditioning whole wheat grains in a solution containing a yeast composition that reduces asparagine using different processing parameters (such as yeast level, moisture level, and conditioning duration), as shown in Table 1.

[0074] Table 1

[0075] variable unit Low middle high yeast level Percentage of DM in kernels 0.2 1 2 Moisture level ％ 16 18 21 Duration of conditioning operation Hour 14 22 30

[0076] Whole wheat grains were conditioned in a solution containing yeast that reduces asparaginase activity. The yeast used in the conditioning medium was baker's yeast, which had been grown on a selective medium to promote asparaginase activity. The whole grains had a moisture content of less than 15% prior to conditioning. The yeast was dissolved in water, and this solution was added to the conditioning medium to bring the yeast level between 0.2% and 2% by weight of the conditioning mixture. Conditioning was performed for varying durations from 14 to 30 hours to achieve moisture contents between 16% and 21%. A control sample of whole wheat grains was conditioned in aqueous solution for 14 hours to achieve a moisture content of 16%.

[0077] Table 2 provides the specific conditioning conditions for each sample.

[0078] Table 2

[0079]

[0080] After conditioning, whole wheat grains were milled, and the asparagine content of the resulting flour was measured. The experimental results are shown in Table 3 below. Figure 2 middle.

[0081] Table 3

[0082]

[0083] Compared to the control sample (S4), samples S1 and S9 achieved a reduction of approximately 77% in free asparagine. Sample S1 was conditioned for 14 hours in a conditioning medium containing 2% asparagine-reducing yeast until the moisture content reached 16%, while sample S9 was conditioned for 30 hours in the same medium until the moisture content reached 21%. Sample S2 achieved a reduction of approximately 71% in free asparagine by conditioning for 22 hours in a conditioning medium containing 1% asparagine-reducing yeast until the moisture content reached 21%.

[0084] Example 3

[0085] This example illustrates the reduction of acrylamide in biscuits prepared using refined wheat flour and whole grains obtained by conditioning the whole grains in a solution containing a yeast composition that reduces asparagine.

[0086] Experimental samples of whole wheat grains were conditioned in a solution containing asparagine-reducing yeast. The yeast used in the conditioning medium was baker's yeast, which had been grown on a selective medium to promote asparaginase activity. The whole grains had a moisture content of less than 15% before conditioning. The yeast was dissolved in water, and this solution was added to the conditioning medium. Conditioning was performed under the conditions shown in Table 4. Control samples were conditioned in water without asparagine-reducing yeast. After conditioning, the whole wheat grains were milled without drying, and biscuit dough was prepared. The biscuit dough was baked at a temperature between 190°C and 250°C for 415 seconds. The biscuit contained 33.5% refined flour obtained from the treated whole wheat grains and 3% bran and germ obtained from the treated wheat grains.

[0087] Table 4

[0088]

[0089] As shown in Table 4, compared with the control biscuits that were conditioned without asparagine-reducing yeast, the biscuits made from whole wheat flour obtained from wheat grains treated with asparagine-reducing yeast during conditioning showed a significant reduction in acrylamide content.

[0090] Example 4

[0091] This example demonstrates the further reduction of asparagine that can be achieved when additional cereal components in biscuits are treated with a asparagine-reducing yeast during conditioning. Biscuits were prepared according to Example 3, such that they comprise refined wheat flour and bran and germ obtained from treated wheat grains. Additional cereal components included in the biscuits were oat flakes and other whole grain flours, comprising blends of rye, barley, and spelt wheat. The additional cereal components were treated with the asparagine-reducing yeast under the conditions shown in Table 5 and described below. Biscuit dough was prepared and baked for 415 seconds at a temperature varying between 190°C and 250°C. The biscuits contained 33.5% refined flour and 3% bran and germ obtained in Example 3, as well as 9.5% oat flakes and 8% other whole grain flours, comprising blends of rye, barley, and spelt wheat.

[0092] In one cookie (labeled "Cookie A" in Table 5), the oat flakes were conditioned with asparagine-reducing yeast, while the other whole grain flours were left untreated. In the second cookie (labeled "Cookie B" in Table 5), the other whole grain flours were treated in water with asparagine-reducing yeast, while the oat flakes were left untreated.

[0093] Table 5

[0094]

[0095] As shown in Table 5, compared with the control in Example 3, biscuit A containing treated wheat flour, treated bran and germ, treated oat flakes, and untreated other whole grain flours showed a 72% reduction in asparagine. Compared with the control in Example 3, biscuit B containing treated wheat flour, treated bran and germ, treated other whole grain flours, and untreated oat flakes showed a 28.5% reduction in asparagine.

[0096] Example 5

[0097] This example illustrates the reduction of acrylamide in biscuits where all grain ingredients were treated with asparagine-reducing yeast. Biscuits were prepared containing refined wheat flour treated according to Example 3, as well as bran and germ, and containing the same amount, and oat flakes and other whole grain flours treated according to Example 4, containing the same amount. As shown in Table 6, the biscuits where all grain ingredients were treated with the asparagine-reducing composition showed a 52% reduction in acrylamide content compared to the control in Example 3 where no grain ingredients were treated with the asparagine-reducing composition.

[0098] Table 6

[0099] sample Acrylamide content (ng / g) Acrylamide reduction control material 300 0 All processed grains 145 52％

[0100] Those skilled in the art will recognize that many other modifications, alterations, and combinations can be made to the embodiments described above without departing from the scope of the present invention, and such modifications, alterations, and combinations will be considered to fall within the scope of the present invention.

Claims

1. A method for reducing the asparagine content in whole grain flour used in the production of baked goods, the method comprising: The whole grain is treated by conditioning it in an aqueous solution of asparaginase to provide a conditioning mixture of the asparaginase and the whole grain, thereby hydrating and degrading the asparagine in the whole grain. During conditioning, the concentration of the asparaginase in the aqueous solution is at least 2550 ppm. The aqueous solution is 5% to 15% by weight of the conditioning mixture, and the conditioning operation is performed for 4 to 24 hours to obtain a grain moisture content of 16% to 22%, hydrating the bran and germ of the whole grain without substantially wetting the endosperm, so that asparaginase activity is concentrated in the bran and germ of the whole grain. The treatment produces whole grains with reduced asparagine content; as well as Conditioned whole grains are milled to obtain whole grain flour with reduced asparagine content. The whole grains mentioned therein were not cooked before conditioning, and The treatment reduces the asparagine content of the whole grain flour by at least 25%.

2. The method according to claim 1, wherein the asparaginase is derived from Aspergillus oryzae.

3. The method according to claim 1, wherein the asparaginase has an asparaginase activity of 3500 ASNU per gram of enzyme.

4. The method according to claim 1, wherein the whole grain flour has an asparagine content of not more than 250 ppm.

5. The method of claim 1, wherein the conditioning operation is performed at ambient temperature.

6. The method according to claim 1, wherein the conditioning operation is performed at a temperature of 10°C to 60°C.

7. The method of claim 1, wherein at least some of the asparaginase is absorbed by the whole grain during conditioning and is retained in the whole grain flour after milling.

8. The method of claim 1, wherein the milling operation comprises milling the whole grain to obtain bran and germ fractions and endosperm fractions.

9. The method of claim 8, wherein the bran and germ fraction is subjected to a stabilization treatment to form a stabilized bran and germ fraction, and the stabilized bran and germ fraction is combined with the endosperm fraction to form a stabilized whole grain flour with reduced asparagine levels.

10. The method of claim 1, wherein the whole grain comprises one or more grains selected from the group consisting of: wheat, oats, corn, rice, wild rice, rye, barley, buckwheat, dry wheat, millet, spelt wheat, and sorghum.

11. A whole grain flour having a reduced asparagine content, said whole grain flour comprising asparaginase, and obtained by the method of claim 1, wherein, Compared to a control whole grain flour made from whole grains that have not been treated with asparaginase, the whole grain flour has a reduction of at least 25% in asparagine and an asparagine content of 250 ppm or less.

12. A method for reducing the asparagine content in whole grain flour used in the production of baked goods, the method comprising: The whole grain is treated by conditioning it in an aqueous solution of asparagine-reducing yeast to provide a conditioning mixture of the asparagine-reducing yeast and the whole grain, thereby hydrating and degrading the asparagine in the whole grain. The aqueous solution of the yeast that reduces asparagine is 5% to 15% by weight of the conditioning mixture. The asparagine-reducing yeast is contained in an amount of 0.1% to 4.0% by weight of the conditioning mixture. The conditioning process is performed for 10 to 32 hours to obtain a grain moisture content of 16% to 22% and hydrating the bran and germ of the whole grain without substantially wetting the endosperm, so that the yeast activity that reduces asparagine is concentrated in the bran and germ of the whole grain. The treatment produces whole grains with reduced asparagine content; Conditioned whole grains are milled to obtain whole grain flour with reduced asparagine content. The whole grains mentioned therein were not cooked before conditioning, and The treatment reduces the asparagine content of the whole grain flour by at least 25%.

13. The method of claim 12, wherein the conditioning operation is performed at a temperature of 10°C to 60°C.

14. The method of claim 12, wherein the milling operation comprises milling the whole grain to obtain bran and germ fractions and endosperm fractions, wherein the bran and germ fractions are subjected to a stabilization treatment to form stabilized bran and germ fractions, and the stabilized bran and germ fractions are combined with the endosperm fractions to form stabilized whole grain flour with reduced asparagine levels.

15. A whole grain flour having a reduced asparagine content, said whole grain flour comprising asparagine-reducing yeast, and obtained by the method of claim 12, wherein, Compared to a control whole grain flour made from whole grains that have not undergone asparagine reduction treatment with yeast, the whole grain flour has at least a 25% reduction in asparagine and an asparagine content of 250 ppm or less.

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