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. Available from: http://www.danisco.com/cms/connect/corporate/products%20
and%20services/product%20range/emulsifiers.htm Accessed on August 26,
2006.
Armero, E. and Collar, C. (1996). Anti-staling additives, flour type and sourdough process effects on functionality of wheat doughs. J. of Food Sci. 61:
299–303.
Armero, E. and Collar, C. (1998). Crumb firming kinetics of wheat breads with
anti-staling additives. J. Cereal Sci. 28: 165–174.
Asghar, A., Anjum, F.M., Ahmed, A., Hussain, S., and Tariq, M.W. (2005).
Effect of polyols on quality and acceptability of frozen dough bread. Pak. J.
Food Sci. 15(1–2): 11–14.
Asghar, A., Anjum, F.M., Allen, J.C., Daubert, C.R., and Rasool, G. (2009).
Effect of modified whey protein concentrates on empirical and fundamental dynamic mechanical properties of frozen dough. Food Hydrocolloids
23:1687–1692.
Asghar, A., Anjum, F.M., Tariq, M.W., and Hussain, S. (2005). Effect of carboxy
methyl cellulose and gum arabic on the stability of frozen dough for the bakery
products. Turk. J. Biol. 29: 237–241.
Azizi, M., and Rao, G. (2004). Effect of surfactant gels on dough rheological
characteristics and quality of bread. Crit. Rev. in Food Sci. and Nutrition 44:
545–522.
Barbut S. and Foegeding, E.A. (1993). Ca2+ induced gelation of pre-heated
whey protein isolate. J. Food Sci. 58: 867–871.
Barrett, A., Cardello, A., Maguire, P., Richardson, M., Kaletunc, G., and Lesher,
L. (2002). Effects of sucrose ester, dough conditioner, and storage temperature
on long-term textural stability of shelf-stable bread. Cereal Chem. 79: 806–
811.
Bechtel, W.G., Meisner, D.F., and Bradley, W.B. (1953). The effect of the crust
on the staling of bread. Cereal Chem. 30: 160–168.
Berglund, P.T., Shelton, D.R., and Freeman, T.P. (1991). Frozen bread dough
ultra structure as affected by duration of frozen storage and freeze thaw cycles.
Cereal Chem. 68: 105–107.
Bloksma, A.H., (1990). Dough structure, Dough rheology and baking quality.
Cereal Foods World. 35(2): 237–244.
Bollain, C., Angioloni, A., and Collar, C. (2005). Bread staling assessment of
enzyme-supplemented pan breads by dynamic and static deformation measurements. Eur. Food Res. Technol. 220: 83–89.
Cocup, R.O. and Sanderson, W.B. (1987). Functionality of dairy ingredients in
bakery products. Food Technol. 41: 86–90.
Collar, C., Martinez, J.C., Andreu, P., and Armero, E. (2000). Effects of enzyme
associations on bread dough performance: A response surface analysis. Food
Sci. Technol. Int. 6(3): 217–226.
Conrado, L. S. Veredas, V. Nobrega, E. S., and Santana, C. C. (2005). Concentration of α-lactalbumin from cow milk whey through expanded bed adsorption
using a hydrophobic resin, Brazilian J. Chemical Engineering. 22(4): 501–
509.
Cook, M. L. (1994). Structural changes in the U.S. grain and oilseed sector. In:
Food and Agricultural Markets: The Quiet Revolution. pp. 118–125. Chertz,
L. and Lynn, M., Eds., USDA Economic Research Service, Washington, DC.
De Stefanis, V.A.D. (1995) Functional role of microingredients in frozen doughs.
In: Frozen Refrigerated Doughs and Batters. pp. 91–117. Kulp, K., Lorenz,
K., and Brummer, J., Eds., The Am. Assoc. Cereal Chem. Inc., St. Paul,
Minnesota.
De Wit J.N. (1998). Nutritional and functional characteristics of whey proteins
in food products. J Dairy Sci. 81: 597–608.
Delaney, R.A.M. (1976). Composition, properties and uses of whey protein
concentrate. J. Soc. Dairy Technol. 29: 91–101.
Duran, E., Leon, A., Barber, B., and Barber, C.B. (2001). Effect of low molecular
weight dextrins on gelatinization and retrogradation of starch. Eur. Food Res.
and Technol. 212: 203–207.
El-Dash, A.A. and Johnson, J.A. (1967). Protease enzymes: Effect on bread
flavor. Cereal Sci. Today. 12: 282–288, 312.
Elofsson, C., Dejmek, P., Paulsson, M., and Burling, H. (1997). Characterization
of a cold- gelling whey protein concentrate. Int. Dairy Journal. 7: 601–608.
Erdogdu-Arnoczky, N., Czuchajowska, Z., and Pomeranz, Y. (1996). Functionality of whey and casein in bread making by fixed and optimized procedures.
Cereal Chem. 73: 309–316.
Gallagher, E., Gormley, T.R., and Arendt, E.K. (2004). Recent advances in the
formulation of gluten-free cereal-based products. Trends in Food Sci. Technol.
15: 143–152.
Giannou, V., Tzia, C., and Bail, A.L. (2006). Quality and safety of frozen
bakery products. In: Handbook of Frozen Food Processing and Packaging.
pp. 481–501. Sun, D-W., Ed., CRC Press , Boca Raton, FL.
Gray, J.A. and Bemiller, J.N. (2003). Bread staling: Molecular basis and control.
Compr. Rev. Food Sci. Food Safety. 2: 1–21.
Grosskreutz, J.C. (1961). A lipoprotein model of wheat gluten structure. Cereal
Chem. 38: 336–342.
Ha, E., and Zemel, M.B. (2003). Reviews: Current topics. Functional properties
of whey, whey components, and essential amino acids: mechanisms underlying health benefits for active people. (Review), J. of Nutritional Biochem. 14:
251–258.
Hamer, R.J. (1995). Enzymes in the baking industry. In: Enzymes in Food
Processing, 2nd Edition. pp. 190–222. Tucker, G.A. and Woods, L.F.J., Eds.,
Blackie Academic and Professional, Glasgow.
Haros, M., Rosell, C.M., and Benedito, C. (2002). Effect of different carbohydrates on fresh bread texture and bread staling. Eur. Food Res. and Technol.
215: 425–430.
Harper, W.J. and Zadow, J. G. (1984). Heat induced changes in whey protein
concentrate as related to bread manufacture. NZ J. of Dairy Sci. & Technol.
19: 229–237.
Haseborg, E. and Himmelstein, A. Quality problems with high fiber breads
solved by using hemicellulase enzymes. Cereal Foods World 33: 419–422.
Hobman, P.G. (1992). Ultrafiltration and manufacture of whey protein concentrates. In: Whey and Lactose Processing. p. 195. Zadow, J.G., Ed., Elsevier
Appl. Sci., NY.
Holcomb, R. (2000). More than just adding wheat to your crop. In: Future
Farms: New Ideas for Family Farms and Rural Communities. pp. 28–31.
Kerr Center for Sustainable Agriculture, Poteau, OK.
Holmes, J.T., and Hoseney, R.C. (1987). Freezing and thawing rates and the
potential of using a combination of yeast and chemical leavening. Cereal
Chem. 64(4): 348–351.
Hosomi, K., Nishio, K., and Matsumoto, H. (1992). Studies on frozen dough
baking. I. Effects of egg yolk and sugar ester. Cereal Chem. 69: 82–92.
Hudson, H.M., Daubert, C.R., and Foegeding, E.A. (2000). Rheological and
physical properties of derivitized whey protein isolate powders. J Agric Food
Chem. 48: 3112–3119.
Huffman, L.M. (1996). Processing whey protein for use as a food ingredient.
Food Technol. 50: 49–52.
Hung, S.C. and Zayas, J.F. (1992). Functionality of milk proteins and corn germ
protein flour in comminuted meat products. J. Food Quality. 15(2): 139–
152.
UTILIZATION OF DAIRY BYPRODUCT PROTEINS, SURFACTANTS, AND ENZYMES IN FROZEN DOUGH
Imafidon, G.I., Farkye, N.Y., and Spanier A.M. (1997). Isolation, purification
and alteration of some functional groups of major milk proteins: A review.
Crit. Rev. Food Sci. & Nutr. 37: 663–689.
Inoue, Y. and Bushuk, W. (1991). Studies on frozen doughs. I. Effects of frozen
storage and freeze–thaw cycles on baking quality and rheological properties.
Cereal Chem. 68: 627–631.
Inoue, Y., and Bushuk W. (1992). Studies on frozen doughs. II. Flour quality
requirements for bread production from frozen dough. Cereal Chem. 69:
423–428.
Inoue, Y., Sapirstein, H.D., and Bushuk, W. (1995). Studies on frozen doughs.
IV. Effect of shortening systems on baking and rheological properties. Cereal
Chem. 72(2): 221–226.
Ishizuka, T. and Nakamura, S. (1974). Effect of fatty acid moiety in sucrose
ester on gelatinization of potato starch and its retrogradation. J. Japanese
Society of Nutr. & Food Sci. 27: 221–224
Jacobson, K.A. (1997). Whey protein concentrates as functional ingredients in
baked goods. Cereal Foods World. 42:138–141.
Jiancai, Li. and Mingrou, G. (2006). Effects of polymerized whey proteins on
consistency and water-holding properties of goat’s milk yogurt. J. of Food
Sci. 71(1): 34–38.
Jiang, Z., Li, X., Yang, S., Li, L., and Tan, S. (2005). Improvement of the
breadmaking quality of wheat flour by the hyperthermophilic xylanase from
Thermotoga maritima. Food Res. Int. 38: 37–43.
Joint FAO/WHO Expert Committee on Food Additives (JECFA) Evaluation
(1995). http://www.inchem.org/documents/jecfa/jeceval/ jec 1969.htm.
Ju, Z. and Kilara, A. (1998). Textural properties of cold-set gels induced from
heat-denatured whey protein isolates. J. Food Sci. 63: 288–292.
Kadharmestan, C., Baik, B.K., and Czuchajowska, Z. (1998). Whey protein
concentrate treated with heat or high hydrostatic pressure in wheat based
products. Cereal Chem. 75: 762–766.
Kenny, S., Wehrle, K., Auty, M., and Arendt, E.K. (2001). Influence of Sodium
caseinate and whey protein on baking properties and rheology of frozen
dough. Cereal Chem. 78(4): 458–463.
Kester, J.J. and Richardson, T. (1984). Modification of whey proteins to improve
functionality. J. of Dairy Sci. 67: 2757–2774.
Kinsella, J.E. (1984). Milk proteins: Physicochemical and functional properties.
Crit. Rev. Food. Sci. & Nutr. 21:197–262.
Kinsella, J.E. and Whitehead, D.M. (1989). Proteins in whey: chemical, physical, and functional properties. Adv. in Food & Nutr. Res. 33: 343–438.
Krog, N. (1981). Theoretical aspects of surfactants in relation to their use in
bread making. Cereal Chem. 58: 158–164.
Lagendijk, J. and Pennings, H.J. (1970). Relation between complex formation
of starch with monoglycerides and the firmness of bread. Cereal Science
Today. 15: 354–365.
Lou, J. and Wilson, W.W. (1998). Value-added wheat products: Analysis of
markets and competition. Agricultural Economics Report No. 386, Department of Agricultural Economics, North Dakota State University, April
1998.
Maarel, M.J.E.C., Veen, B., and Uitdehoog, J.C.M. (2002). Properties and applications of starch-converting enzymes of the α-amylase family. J. of Biotechnol. 94: 137–155.
Maat, J., Roza, M., Verbakel, J., Stam, H., Santosdasilva, M.J, and Bosse,
M. (1992). Xylanases and their application in bakery. In: Xylans and Xylanases. pp. 349–360. Visser, J., Beldman, J.G., Kustersvan, M.A., and Voragen, A.G.J., Eds., Elsevier Science, Amsterdam.
Mangino, M.E. (1984). Physicochemical aspects of whey protein functionality.
J. of Dairy Sci. 67: 2711–2722.
Martinez-Anaya, M.A. and Jimenez, T. (1997). Functionality of enzymes that
hydrolyse starch and non-starch polysaccharide in bread making. Zeitschrift
fur Lebensmittel Untersuchung und Forschung. 205: 209–214.
Mathewson, P.R. (2000). Enzymatic activity during bread baking. Cereal Foods
World. 45: 98–101.
Matuda, T.G., Parra, D.F., Lugao, A.B., and Tadini, C.C. (2005). Influence
of vegetable shortening and emulsifiers on the unfrozen water content and
textural properties of frozen French bread dough. Lebensmittel- Wissenschaft
und –Technologie. 38: 275–280.
381
McClements, D. and Keogh, M.,(1995). Physical properties of cold-setting gels
formed from heat-denatured whey protein isolate. J. Sci. Food & Agric. 69:
7–14.
McIntosh, G.H., Royle, P.J., Le Lue, R.K., Regester, G.O., Johnson, M.A.,
Grinsted, R.L., Kenward, R.S., and Smithers, G.W. (1998). Whey proteins as
functional food ingredients. Int. Dairy Journal. 8: 425–434.
Melachouris, N. (1984). Critical aspects in development of whey protein concentrate. Effect of various heat treatments on structure and solubility of whey
proteins. J. of Dairy Sci. 67: 2693–2700.
Metler, E. and Seibel, W. (1993). Effects of emulsifiers and hydrocolloids on
whole wheat bread quality: a response surface methodology study. Cereal
Chem. 70: 373–377.
Morr, C.V. (1982). Functional properties of milk proteins and their use as food
ingredients. In: Developments in Dairy Chemistry 1. Proteins. pp. 273–299.
Fox, P.F., Ed., Applied Science Publishing, NY.
Morr, C.V. (1992) Whey utilization. In: Whey and Lactose Processing. p. 133.
Zadow, J.G., Ed,. Elsevier Appl. Sci., NY.
Morr, C.V. and Foegeding, A.E. (1990). Composition and functionality of commercial whey and milk protein concentrates and isolates: A status report.
Food Technol. 44: 100–104.
Morr, C.V. and Ha, E.Y.W. (1993). Whey protein concentrates and isolates:
processing and functional properties. Crit. Rev. Food Sci. & Nutr. 33: 431–
476.
Morr. C.V. (1984). Production and use of milk proteins in food. Food Technol.
38: 39–48.
Nakamura, M., Sato, K., Koizumi, S., Kawachi, K. (1995). Preparation and
properties of salt-induced gel of whey protein. J. Japan Soc. Food Sci. 42:
1–6.
Piazza, L. and Masi, P. (1995). Moisture redistribution throughout the bread
loaf during staling and its effect on mechanical properties. Cereal Chem. 72:
320–325.
Pisesookbunterng, W. and D’appolonia, B. (1983). Bread staling studies. I.
Effects of surfactants on moisture migration from crumb to crust and firmness
values of bread crumb. Cereal Chem. 60: 298–300.
Poutanen, K. (1997). Enzymes: An important tool in the improvement of the
quality of cereal foods. Trends in Food Sci. and Tech. 8(9): 300–306.
Qi Si, J. (1997). Synergistic effect of enzymes for breadmaking. Cereal Food
World. 1997, 42: 802–807.
Rao, P.A., Nussinovitch, A., and Chinachoti, P. (1992). Effects of selected
surfactants on amylopectin recrystallization and on recoverability of bread
crumb during storage. Cereal Chem. 69: 613–618.
Resanen, J., Laurikainen, T., and Autio, K. (1997). Fermentation stability and
pore size distribution of frozen prefermented lean wheat doughs. Cereal
Chem. 74(1): 56–62.
Ribotta, P.D., Leon, A.E., and Anon, M.C. (2001). Effect of freezing and
frozen storage of doughs on bread quality. J. Agri. Food Chem. 49(2): 913–
918.
Ribotta, P.D., Perez, G.T., Leon, A.E., and Anon, M.C. (2004). Effect of emulsifier and guar gum on micro structural, rheological and baking performance
of frozen bread dough. Food Hydrocolloids. 18(2): 305–313.
Rouau, X., El-Hayek, M.L., and Moreau, D. (1994). Effect of an enzyme preparation containing pentosanases on the bread making quality of flours in relation to changes in pentosan properties. J. Cereal Sci. 19: 259–272.
Sato, K., Nakamura, M., Koizumi, S., and Kawachi, K. (1995). Changes in
hydrophobicity and SH content on salt-induced gelation of whey protein. J
Japan Soc. Food Sci. 42: 7–13.
Sato, N., Sato, M. and Nagashima, A. (1991). Effect of an enzyme preparation
containing pentosanases on the breadmaking quality of flours in relation to
changes in pentosan properties. J. Cereal Sci. 19: 259–272.
Schmidt, R.H., Packard, V.S., and Morris, H.A. (1984). Effect of processing on
whey protein functionality. J. Dairy Sci. 67: 2723–2733.
Schroeder, E. (1999). Frozen Dough: In the Footsteps of Fresh Baked. Milling
& Baking News. June 29, 1999.
Schultz, A.S., Schoonover, F.D., Fisher, R.A., and Jacker, S.S. (1952). Retardation of crumb starch staling in commercial bread by bacterial α-amylase.
Cereal Chem. 29: 200–207.
382
A. ASGHAR ET AL.
Sherwin, C. (1995). Use of whey and whey products in baked goods. AIB
Technical Bulletin Vol. XVII, No. 11. Am. Inst. Baking, Manhattan, KS.
Stahel, N. (1983). Dairy proteins for the cereal foods industry: Functions selection and usage. Cereal Foods World. 28: 453–454.
Stampfli, l. and Nersten, B. (1995). Emulsifiers in breadmaking-a review. Food
Chem. 52: 353–360.
Stutz, R.L., Del Vechhio, A.J., and Tenney, R.J. (1973). The role of emulsifiers
and dough conditioners in foods. Food Product Development. 10: 52–58.
Tamstorf, S., Jonsson, T., and Krog, N. (1986). The role of fats and emulsifiers in
baked products. In: Chemistry and Physics of Baking. pp. 75–88. Blanshard,
J., Frazier, P., and Galliard, T., Eds.,The Royal Society of Chemistry, Bristol.
Thomsen, B. (1994). Whey protein texturizer. Eur. Food & Drink Rev. 46–47.
Turgeon, S.L., Gauthier, S.F., and Paquin, R. (1992). Emulsifying property of
whey peptide fractions as a function of pH and ionic strength. J. Food Sci.
57(3): 601–604, 634.
Valjakka, T.T., Ponte, J.G., and Kulp, K. (1994). Studies on a raw-starch digesting enzyme. I. Comparison to fungal and bacterial enzymes and an emulsifier
in white pan bread. Cereal Chem. 71:139–144.
Van Dam, H.W. and Hille, J.D.R. (1992). Yeast and enzymes in breadmaking.
Cereal Foods World. 37(3): 245–252.
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Van den Hoven, M. (1987). Functionality of dairy ingredients in meat products.
Food Technol. 41(10): 72–77, 103.
Vardhanabhuti, B., Foegeding, E.A., McGuffy, M.K., Daubert, C.R., and Swaisgood, H.E. (2001). Gelation properties of dispersions containing polymerized
and native whey protein isolate. Food Hydrocolloids 15:165–175.
Varriano, M.E., Hsu, K.H., and Mahdi, J. (1980). Rheological and structural
changes in frozen dough. Baker’s Digest. 54(1): 32–36.
Wolt, M. and D’Appolonia, B. (1984). Factors involved in the stability of frozen
dough. II. The effects of yeast type and dough additives of frozen dough
stability. Cereal Chem. 61: 213–221.
Yamauchi, H., Nishio, Z., Takata, K., Oda, Y., Yamaki, K., Ishida, N., and Miura,
H. (2001). The quality of extra strong flour used in bread production with
frozen dough. Food Sci. and Tech. Res. 7(2): 135–140.
Yousif, A.K. (1998). Concentration of acidic whey and its functionality in French
type bread. Intl. J. Dairy Tech. 51(3): 72–76.
Zayas, J.F. (1997). Functionality of Proteins in Food. Springer, New York, pp.
1–5.
Zobel, H. and Kulp, K. (1996). The staling mechanism. In: Baked Good
Freshness. pp. 1–64. Hebeda, E. and Zobel, H., Eds., Marcel Dekker,
NY.