Utilization of dairy byproduct proteins, surfactants, and enzymes in frozen dough

Critical Reviews in Food Science and Nutrition, 51:374–382 (2011) C Taylor and Francis Group, LLC Copyright
ISSN: 1040-8398 print / 1549-7852 online DOI: 10.1080/10408391003605482 Utilization of Dairy Byproduct Proteins, Surfactants, and Enzymes in Frozen Dough ALI ASGHAR,1 FAQIR MUHAMMAD ANJUM,1 and JONATHAN C. ALLEN2 1 2 National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan 38040 Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695-7624 Use of natural additives is gaining popularity among the masses as they are becoming more conscious about their diet and health. Frozen dough products are one of the recent examples of value-added cereal products which face stability problems during extended storage periods of times. Dairy whey proteins, surfactants, and certain enzymes are considered important natural additives which could be used to control the water redistribution problem in the dough structure during the storage condition. They interact with the starch and gluten network in a dough system and thus behave as dough improvers and strengtheners. These natural additives not only help to bind extra moisture but also to improve texture and sensory attributes in frozen dough bakery products. Keywords frozen dough, dairy byproducts proteins, surfactants, enzymes, bread quality INTRODUCTION There was a time when the production and export of only raw commodities was considered a priority achievement for a developing economy. But mechanization and adding value to raw commodities has become the emphasis in the modern era. With the increase in urbanization and industrialization, there is rapid development towards the value-addition sector in every industry. Among food processing industries, frozen and refrigerated dough bakery products are considered among one of the fastest growing segments. With the passage of time, different kinds of new additives are being developed and their use in the baking business is also gaining popularity. Due to rapid increase in the frozen dough production and utilization, problems arise that can be solved by use of certain additives and chemical agents. All the compounds that interact with water can affect the quality of the resulting bakery product. A lot of compounds and additives are available that have water binding and gelling properties. A wide range of additives are available and natural additives are needed to meet current consumer concepts of good nutrition. Proteins from dairy sources, like whey proteins, also have the potential of thickening functionality just like other ingre- dients as hydrocolloids, starches, and other thickeners in food systems (Hudson et al., 2000). Surfactants and emulsifiers are also considered safe and natural food additives. In this article the effects of dairy byproducts like whey protein concentrates and surfactants on the quality characteristics of breads and other bakery products made from frozen dough are reviewed. HISTORY, EVOLUTION, AND POTENTIAL OF FROZEN DOUGH Although bread making is one of the oldest technologies of human history, this technology continues to develop and evolve. Even people in prehistoric times were aware of making breads to fulfill basic human nutritional needs. If we look into history we find that between 4000 and 3500 B.C., Egyptians were the first to use yeast as leavening agents in the baking process. Since its inception the baking industry has undergone evolutionary steps such that storage of dough under freezing conditions is now a common practice that results in ease in handling, transportation, and production of fresh bread. Freezing technology is commonly being employed for the preservation of food commodities. In the last decade the production of frozen dough has increased greatly because of diAddress correspondence to Dr. Ali Asghar, National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan. Tel.: rect sales to the consumers and the growing number of in-store bakeries. The bakery industry has increasingly exploited the +92(300)7671084. E-mail: ali asghar11@hotmail.com 374 UTILIZATION OF DAIRY BYPRODUCT PROTEINS, SURFACTANTS, AND ENZYMES IN FROZEN DOUGH 375 Figure 1 Process flow diagram of normal and frozen dough baking. — Continuous line is the ordinary dough production line · · ·· Dotted lines represent the frozen dough processing line. Adapted from Giannou et al., 2006. applications of freezing technology. The growing interest of the market toward frozen bakery goods has been driven mainly by the economic advantage of a centralized manufacturing and distribution process as well as the standardization of product quality (Matuda et al., 2000). The frozen dough product segment is the third largest in the baking industry. Demand for quick and convenient food items is increasing due to changing life styles. The fast-developing frozen dough industry is providing easy alternatives to traditional bakery products. Consumers who make bread from frozen dough expect products with satisfactory quality and sensory characteristics that should not differ much from the traditional fresh ones. The typical process flow diagram for frozen dough differs somewhat from that of non-frozen doughs and the major differences are shown in Fig.1. Frozen dough is one of the emerging markets in the world. Due to high market potential and current lack of competition, there is a huge potential of growth of this sector. The total market for frozen dough products covers retail grocery sales and food service (Holcomb et al., 2000; Lou et al., 1998). Now, due to increasing consumer demand for frozen dough products, several major industrial groups are entering this business (Cook et al., 1994). Increasing growth in the frozen dough business observed in recent years accompanies the trend for more meals prepared outside of the home (Schroeder, 1999). PROBLEMS WITH FROZEN DOUGH STOPPED HERE There are several problems associated with the frozen dough bakery products. One of the problems in this sector is the changes in the water distribution that occur during prolonged frozen storage and freeze thaw cycles. This contributes to the extended proofing time and reduced loaf volume of frozen dough breads. Ice crystal formation is also a major cause of weakening of the protein network in the dough system that is responsible for gas retention (Berglund et al., 1991; Varriano et al., 1980). Freezing and thawing in the frozen dough leads to decreasing the dough strength which also results in the reduction in final loaf volumes of breads (Bloksma, 1990; Resanen et al., 1997; Inoue and Bushuk, 1992; Holmes and Hoseni, 1987; Yousif, 1998; Asghar et al., 2005). The shelf life of fresh bakery products is usually a few days and after proper baking, the product, i.e., bread, is usually of good quality and sensory features. The color of the fresh bread is usually brownish and it gives a crunchy crust, a pleasant roasty aroma, fine slicing characteristics, a soft and elastic crumb texture, and a moist mouthfeel. During the storage of fresh bread and other bakery items several physical and chemical changes occur in the bakery products which are also known as staling. The staling also results in the deterioration of bread quality because it loses freshness and crispiness. On the other hand, crumb firmness and rigidity increase due to the staling process. During the cooling stage, consistent changes in the moisture content occur that contribute to a temperature gradient within the bread. Usually the interior of the bread has more moisture than its outer layers (Yamauchi et al., 2001). This produces a difference in vapor pressure between the crust and crumb, resulting in moisture migration during the cooling stage. Part of the moisture travels from the crust to the surrounding atmosphere. This mass transfer resistance that exists at the interface between the bread crust and the atmosphere around it influences the rate of moisture migration (Piazza and Masi, 1995). In order to control these stability problems in frozen dough, new processing techniques and additives that increase shelf life, enhance quality and retain stability, and the sensory and 376 A. ASGHAR ET AL. nutritional characteristics of the frozen dough bakery products during prolonged periods of storage are recommended. DAIRY BYPRODUCT PROTEINS Sources and Functional Properties Functional properties of the proteins affect the behavior of the food products during preparation, processing, storage, and consumption and thus contribute to the quality and sensory attributes of the food systems (Kinsella, 1984). Dairy proteins have traditionally been one of the major protein sources and have several functional properties. Due to increasing production of cheese, large amounts of whey proteins are available which also leads to the production of a whole range of whey protein concentrates and isolates (Hobman, 1992). Functional properties of whey proteins are influenced by the chemical and physiochemical properties (Schmidt et al., 1984). Thousands of tons of whey protein concentrates have become available as a relatively cheap byproduct due to improvements in dairy processing techniques during cheese making (Hung and Zayas, 1992). Current separation technologies allow for the isolation and purification of dairy proteins into natural food ingredients, many of which exhibit excellent functional properties, including foaming, emulsifying, thickening, texturization, and gelation (Imafidon et al., 1997). Whey is a general term that describes the watery, natural byproduct expressed during cheese manufacture. This protein fraction is comprised of a number of individual proteins including β-lactoglobulin, α-lactalbumin, bovine serum albumin, and immunoglobulins. Of these individual proteins, β-lactoglobulin and α-lactalbumin are found in the highest concentrations and therefore have the greatest impact on the functionality of whey protein ingredients. These proteins account for approximately 20% of the total protein found in milk and, unlike casein, remain soluble at pH 4.6 and 30◦ C (Huffman, 1996). Different components of cheese whey are presented in Table 1. Whey protein concentrates are commonly manufactured using filtration techniques to concentrate protein based on molecular weight differences. During ultrafiltration, lactose, salts, and other low molecular weight materials pass through a membrane in the permeate while higher molecular weight components such as protein are concentrated. The concentrated protein solution is then spray dried to form a whey protein concentrate powTable 1 Main protein components of cheese whey (Conrado et al., 2005) Protein α-lactoglobulin B-lactoglobulin BSA IgG, IgA, IgM Lactoperoxidase Lactoferrin Concentration (g/l) Molecular weight (kDA) 1.5 3–4 0.3–0.6 0.6–0.9 0.06 0.5 14.2 18.4 69 150–900 78 78 der, which generally ranges in protein concentration from 34 to 89%. High protein whey protein concentrates (>80% protein) are used in a wide range of foods, including meats, bakery, and confectionaries because of their ability to impart viscosity, hold water, gel, foam, and emulsify (Huffman, 1996; Morr, 1982). Considerable research in protein functionality and nutrition have shown that whey proteins possess unsurpassed functional and nutritional properties (Morr and Foegeding, 1990), making them excellent functional ingredients for use in manufactured food products. Newer processing technologies have made it economically possible to concentrate and exploit whey protein as a food ingredient (Huffman, 1996; Morr and Foegeding, 1990; McIntosh et al., 1998). Currently available whey protein ingredients are lactalbumin, whey protein concentrate, and whey protein isolate. Lactalbumin is a powder containing all of the major whey proteins, isolated by heat precipitation at greater than 90◦ C (Huffman, 1996). Whey proteins exist as individual entities with compact, organized, globular conformation (Kinsella and Whitehead, 1989). In some studies, commercially available modified whey protein concentrate powder is produced by heat treatment during homogenization of a whey protein concentrate at slightly alkaline pH, followed by immediate drying (Thomsen, 1994). The dried powder reportedly thickened upon dispersion in a salt solution (Elofsson et al., 1997). The dairy byproduct proteins have unique functional and nutritional properties. Due to their wide range of application, they are considered very useful food additives in different food applications (Kinsella, 1984; Morr, 1984; Morr and Ha, 1993; De Wit, 1998). Polymerized whey proteins are formed when heated at temperatures that would normally form a gel (Vrdhanabhuti et al., 2001; Barbut and Foegeding, 1993; McClements and Keogh, 1995). The textural properties of the different food items could be influenced by the gel-formation properties of the whey and other dairy byproduct proteins. The gels-formation property of these proteins increases the water-holding capacity and is also considered very important to the consumer acceptability of many foods such as processed meat, dairy, and bakery products (Ju and Kilara, 1998; Nakamura et al., 1995; Ha and Zemel, 2003). Role in Frozen Dough The proteins obtained from the dairy sources have unique functional properties. The dairy ingredients that increase water absorption are also found to improve the dough-handling properties in bread and other bakery products (Kinsella, 1984; Stahel, 1983; Cocul and Sanderson, 1987; Asghar et al., 2009). Whey proteins could be processed to exhibit particular functional properties which are desirable in a food system (Mangino, 1984; Kester et al., 1984; Melachouris, 1984; Sherwin, 1995). Important functional properties of whey proteins related to food products are immobilization of water, texture and color improvement, and enhancement of sensory attributes (Mangino, UTILIZATION OF DAIRY BYPRODUCT PROTEINS, SURFACTANTS, AND ENZYMES IN FROZEN DOUGH 1984; van den Hoven, 1987). Whey proteins are used to increase the viscosity and improve the mouthfeel in different food products. As they behave much like hydrocolloids, so these could also be used as functional ingredients to improve the body and texture and enhance the water-binding properties. Functional properties of proteins are governed by their structural characteristics, which in turn may be affected by the pH, the ionic strength, and the temperature (Turgeon et al., 1992). Gluten is the essential structure-building protein in the bakery products and popularity of gluten-free baking is increasing in certain regions (Gallagher et al., 2004). The replacement of gluten presents a major technological challenge, as it is an essential structure-building protein, which is necessary for formulating high quality cereal-based goods. Rising demands for gluten-free products parallels the apparent or real increase in coeliac disease, or other allergic reactions/intolerances to gluten (Gallagher et al., 2004). Whey protein after modification has several functional properties and is widely used as a dough-enhancing additive and it may confer a protective effect on the gluten network in the frozen dough system (Jacobson, 1997). Spoilage in the frozen dough bakery products usually happens due to excessive amount of moisture which becomes available in the frozen dough systems during the prolonged storage periods of time due to the formation of ice crystals which result in the breakdown of gluten network in the dough system. Use of water-binding compounds such as hydrocolloids, humectants, etc., help to absorb the excessive amount of moisture which is released due to the breakdown of the dough gluten network (Asghar et al., 2005). Dairy byproduct proteins are also considered as an excellent nutritional source (Delaney, 1976; Jiancai and Mingrou, 2006) while the important functional properties of these whey proteins in the food applications are hydrophilic, swelling and water retention capacity, and gelling capacity (Zayas, 1997; Morr, 1992). The extent of whey protein denaturation has the greatest influence on the functional properties of dough during the breadmaking process (Harper and Zadow, 1984; Kenny et al., 2001) while heating of whey protein changes its structure from the native, compactly-folded stable structure that is soluble in water to a denatured, unfolded structure with reduced solubility. Addition of native whey protein in the dough showed that it interferes with gluten development and therefore, has a negative effect in bread making. It has also been found that denaturation of whey protein eliminates this negative effect (Harper and Zadow, 1984; Kadharmestan, 1998; Erdogdu-Arnoczky et al., 1996). Whey protein subject to heat treatment could eliminate the undesirable weakening of the gluten network in frozen dough products. Frozen doughs with the addition of heat-treated whey protein concentrates as functional ingredients showed an enhanced gluten network and also resulted in improved baking performance (Kenny et al., 2001). This may be due to its ability to counteract the rheological changes that occur in frozen storage (Wolt and D’Appolonia, 1984). The ability of whey proteins to absorb and bind water is useful in connection with 377 frozen doughs which are mixed, formed, and then held in frozen storage for some length of time before being thawed, proofed, and baked. Dough for bread and rolls is frozen and shipped to smaller bakeries where it is thawed, proofed, and baked. The dough slowly weakens during prolonged storage periods of time which is mainly due to the formation of ice crystals in the dough network which result in the breakdown of gluten network in the dough systems. SURFACTANTS FUNCTIONALITY Surfactants are usually a broad spectrum of lipid chemicals which interact with the gluten network and starch that are present in the dough system. Addition of surfactants in the dough results in the development of soft crust and crumb, finer cell development, and a more firm structure of the gluten network. So these are also used to control and slow down the rate of the totally undesirable staling in the bakery applications. Systematic experiments on rats were conducted in the past to ensure the safety of the use of surfactants in human foods. On the basis of the reports of multiple study groups reporting the safety of these surfactants in the food applications, international organizations like the FAO/ WHO expert committee on food additives have recognized them as safe food additives (JECFA, 1995). Though it is believed that not all the surfactants are approved for use in the food products, common surfactants which are employed in the baking business and sometimes used in combinations along with their structures are shown in Fig. 2. Surfactant Application in Frozen Dough Surfactants have been employed in the baking industry as anti-staling agents, dough modifiers, shortening sparing agents, and as improvers for the production of high-protein breads (Addo et al., 1995). During the storage of the frozen dough, damages in the dough structures are usually reported which also affect the baking performance of the dough. These damages are usually due to the formation of ice crystals in dough systems which damage the gluten network during frozen storage. Surfactants also inhibit starch retrogradation (Melachouris, 1984) which can increase the bread volumes and soft mouthfeel (Sherwin, 1995). The use of surfactants to inhibit retrogradation in frozen dough systems is also effective (Van den Hoven, 1987). Surfactants interact with starch molecules in the dough, particularly with the linear amylase molecules, but also with amylopectin. The formation of these complexes inhibits bread staling either by preventing amylose or amylopectin retrogradation (Zobel and Culp, 1996). These may also reduce water migration from gluten to starch by forming a complex with starch, and be absorbed into the starch surface (Pisesookbunterng and D’Appolonia, 1983; Rao et al., 1989) Surfactants are classified into two general classes, crumb softeners (e.g., monoglycerides) and dough strengtheners (e.g., 378 Figure 2 2006). A. ASGHAR ET AL. Structures of some food surfactants used in baking process (Anon., ethoxylated mono or diglycerides, sodium or calcium stearoyl lactylate, etc.) Some surfactants such as SSL (Sodium steroyl lactylate) exhibit bifunctional properties. Dough strengtheners are highly desirable in the frozen dough systems because they improve the functionality of wheat gluten proteins. During the frozen storage periods, these proteins provide the architectural support to the gluten network in the dough matrix and play a vital role in dough stability (De Stefanis, 1995). SSL is responsible for maintaining volume and softness in fresh and frozen dough products (Varriano et al., 1980; Wolt and D’Appolonia, 1984; Armero et al., 1996). Studies in which the effect of sodium stearoyl-2-lactylate (SSL), diacetyl tartaric acid esters of monoglyceride (DATEM), glycerol monostearate (GMS), and distilled glycerol monostearate (DGMS) on the quality of bread was investigated showed that all surfactant gels improved the loaf volume, specific volume (Ribotta et al., 2004), texture, and overall quality scores of bread (Azizi and Rao, 2004). Monoglycerides basically control the rate of moisture transfer during bread storage and scientists believe that samples stored in frozen conditions supplemented with diacetyltartaric acid ester of monoglycerides could produce breads of greater volume and more open crumb structure than those prepared with the base formulation, i.e., with no additive. Crumb firmness in- creased with frozen dough storage and bread aging time at 4◦ C. Also, the addition of DATEM and guar gum to dough yielded the best improvement in bread loaf volume after dough freezing (Ribotta et al., 2004; 2001). The improvement in the quality of frozen dough due to the addition of DATEM was probably due to the stabilizing effects brought on by its interaction with gluten proteins to form a glutein-DATEM-gliadin complex, thus resulting in improving its stability (Stutz et al., 1973). Hydrophilic sugar esters are helpful in improving the baking and rheological properties of frozen dough (Hosomi et al., 1992). The addition of sucrose esters decreased yeast damage by increasing the amount of non-frozen water in the wheat starch. Also, it was reported that this addition controls the denaturation during freezing in the wheat protein. It is pertinent to note that damage to dough structure is usually caused by ice recrystallization which occurs in the frozen dough system during prolonged storage periods of times. This reduction of damage in the wheat proteins also leads to the minimization of baking loss and improves the baking properties of the frozen dough. (Varriano et al., 1980; Inoue and Bushuk, 1991). Sucrose fatty acid esters are non-ionic surfactants, one of the safest food surfactants being utilized in different food products. Their characteristic properties in food products include emulsifying, foaming, inhibition of crystal growth, and retrogradation of starch. These properties made them unique among surfactants used in bakery products. The addition of sucrose esters in dough formulations produces bread with a fine and soft crumb structure, high volume, and extended shelf life, and improved freeze-thaw stability (Barrett et al., 2002). Interestingly, some surfactants are found to control the retrogradation in the bread and other bakery items. The interaction of the sucrose fatty acid esters mainly with the amylose molecules results in the formation of the inclusion complexes with the helical amylose molecules during gelatinization. These complexes inhibit starch retrogradation resulting in a baked product with longer-duration freshness. These surface-active agents usually form a complex with the starch which is similar to the formation of the iodine and starch complex and thus effective for inhibiting the deterioration of bread and other food products in which starch is present as a main constituent (Ishizuka and Nakamura, 1974). Contrary to this, several types of dough strengtheners could be used to improve the baking quality. Several examples of emulsifiers could be quoted. Mono- and diacylglycerols esterified to mono- and diacetyltartaric acid (DATEM) are anionic oil-in-water emulsifiers are used to improve the quality of bread. These kinds of emulsifiers, also called dough strengtheners, when added to dough improve mixing tolerance, gas retention, and resistance of the dough to collapse. Concerning the final product, this substance improves loaf volume, texture, fine grain, as well as the slicing properties of the breads made from frozen dough (Inoue et al., 1995; Metler and Seibel, 1993; Tamstrof et al., 1986). The crumb-softening effect of these surfactants in the frozen dough bread has been attributed to a number of mechanisms including interactions with protein that serves to UTILIZATION OF DAIRY BYPRODUCT PROTEINS, SURFACTANTS, AND ENZYMES IN FROZEN DOUGH modify the gluten structure (Grosskreutz, 1961; Krog, 1981) and by complexing with amylose (Krog, 1981). 379 positive effect on bread volume is due to the redistribution of water from the pentosan phase to the gluten phase. Xylanases are also known to have anti-staling action during bread storage (Haros et al., 2002). ENZYMES IN BREAD AND FROZEN DOUGH Enzymes have a wide range of application in different industrial processing and in baking α-amylase and protease are widely used. Staling is the major reason of spoilage in bakery products. Because stale products become less acceptable to consumers, it results in huge economic losses to the baking industry (De Stefanis, 1995; Bechtel et al., 1953; Poutanen, 1997). Different enzymes are currently added to the bread-making process for improving dough handling, fresh bread quality, and shelf life (Haros et al., 2002). Several other enzymes also act as dough improvers by modifying one of the major dough components (Maarel et al., 2002). During the process of staling, different physicochemical transformations occur. The most important of these transformations are the retrogradation of starch, gluten-starch interactions, and moisture redistribution between and among components. The most important change associated with bread staling is the gradual increase in crumb firmness (Gray and Bemiller, 2003; Schultz et al., 1952). Enzymes are commonly used to reduce the rate of staling in bakery products. Enzymes are being used increasingly to improve the product quality and functional properties of the frozen dough bakery items. α−Amylase Usually the amount of α-amylase is negligible in the wheat flour and it is necessary to supplement the flour with a certain amount of α-amylase. Amylases can be used to improve or control the dough-handling properties, the volume, the color, and the shelf life of end products (Hamer, 1995). Different sources of α-amylases like cereals, fungal, and bacterial sources have been identified for their use as additives in bread baking. Amylases usually act on damaged starch, reducing its ability to immobilize water, thus increasing dough mobility and resulting in improved dough handling (Martinez-Anaya and Jimenez, 1997). The enzyme-induced changes in dough rheology are also an important reason for the increased bread volume. As α-amylases are starch-hydrolyzing enzymes, they could disrupt the starch network and thereby decrease the amount of available starch for retrogradation and cause reduction in firmness (Schultz et al., 1952; Duran et al., 2001) Xylanase Xylanases are well-known dough conditioners and have reportedly been used to increase loaf volume and the addition of these enzymes did result in a greater firming rate (Jiang et al., 2005; Armero and Collar, 1998; Bollain et al., 2005) and this Lipase Lipases can improve crumb softness of bread. Addition of specific lipases in combination with triglycerides also improves loaf volume, crumb softness, staling rate, and flavor. Antistaling functions of emulsifiers are usually due to their interaction with amylopectin that prevents amylopectin crystallization (Hamer, 1995; Lagendijk and Pennings, 1990). The mechanism of monoglycerides in retarding the firming process is based on the ability of monoglycerides to form complexes with amylose (Stampfli and Nersten, 1995; Valjakka et al., 1994). Protease Protease, that is commonly present in flour due to microbial contamination, plays a major role in gluten dis-aggregation during the mixing process. Sometimes protease is added to high protein hard wheat flour to hydrolyze gluten. This process, termed as “mellowing the gluten,” also helps to improve the mixing properties of the doughs (Van Dam and Hille, 1992). The function of the protease is to depolymerize and weaken the gluten structure of the doughs. The function of protease is to some extent contrary to the action of oxidants and thus helps to control bread texture and improve flavor (De Stefanis, 1995; Hamer, 1995; Matthewson, 2000; El Dash and Johnson, 2000). As proteases modify gluten protein, these interactions are weakened and firming is decreased. Proteases also affect the sensory attributes and texture (El Dash and Johnson, 2000). Sometimes enzymes also show synergistic effects for dough conditioning and for extending shelf life (Qi Si, 1997; Sato et al., 1991; 1995; Collar et al., 2000). The synergistic combination of xylanases with amylase has proven to be beneficial and is used in many improved formulations to control bread staling (Haseborg and Himmelstein, 1988; Rouau et al., 1994; Maat et al., 1992). CONCLUSION AND FUTURE TRENDS Over the past few years, the baking industry has been exploiting the advantages and applications of freezing technology in several frozen dough bakery applications. There is an increase in demand for bakery products with increased shelf life from both ordinary consumers and food service industries. With the passage of time there is continual development of new frozen dough and other bakery products. One such recent trend is the increased utilization of whey protein. It is obvious that the future of the frozen dough industry is promising. Different functional and nutritional properties of 380 A. ASGHAR ET AL. dairy byproduct proteins, surfactants, and certain enzymes make them useful natural food additives for a wide range of applications due to their ability to bind the excess moisture and thus prevent its availability to fungus and other microflora that are major causes of deterioration and staling in the bakery products. Along with its increasing utilization in frozen dough products there is also ongoing research to explore the numerous possible health benefits of whey and other dairy byproduct proteins in different food products. REFERENCES Addo, K., Slepak, M., and Akoh, C.C. (1995). Effects of sucrose fatty acid ester and blends on alveograph characteristics of wheat flour doughs. J. of Cereal Sci. 22: 123–127. Anonymous (2006). Products and services, Emulsifiers in baking. 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