TECHNOLOGY OF CEREALS pasta foods, pet foods, dietary foods and textured permit the use of four of up to 2% lower protein getables products(t v.p. content with no loss in loaf quality The origin of the gluten is of little importance A similar increase in loaf volume could be when used to raise the flour protein content by produced by addition of a variety of commercial only 1-2%: thus, U.K. -grown wheat can be used carbohydrase enzyme preparations(Cauvain and to provide vital gluten, thereby further reducing Chamberlain, 1988) the dependence on imported strong wheat. The vital gluten is generally added to the flour at the mill, particularly in the case of wholemeal Soya flour (McDermott, 1985). Enzyme-active soya flour is widely a bread additive at a level of about 0.7% on Gluten flou four wt. Advantages claimed for its use include beneficial oxidizing effect on the flour, bleaching This is a blend of vital wheat gluten with wheat effect on flour pigments( B-4 carotene due lour, standardized to 40% protein content in the presence of lipoxygenase, increase in loaf volume, U.S.A improvement in crumb firmness and crust appear- ance, and extension of shelf life(Anon, 1988a) Fungal amylase (cf.p.215) The improving action and bleaching propert Besides the use of low levels(e. g 7-10 Farrand of enzyme-active soya flour are due to peroxy Units)of fungal amylase to correct a deficiency radicals that are released by a type-2 lipoxygenase in natural cereal alpha-amylase and improve gas- which has an optimum activity at ph 6. 5. Enzyme- sing(cf p. 198), fungal amylase, sold under such active soya flour has two effects in a flour dough trade names as myl.x and amylzyme, has a it increases mixing tolerance, and it improves marked effect in increasing loaf volume when used dough rheology, viz. by decreasing extensibility at much higher levels as a bread ingredient in rapid and increasing resistance to extension. The action eadmaking systems. Use of high levels is possible of the lipoxygenase is to oxidize the linoleic acid cause the fungal amylase has a relatively low in the lipid fraction of the wheat four, but the thermal inactivation temperature. The fungal action only occurs in the presence of oxygen amylase starts to act during the mixing stage,( Grosch, 1986) when it causes a softening of the dough, which must be corrected by reducing the amount of doughing water, so as to maintain the correct Improving agents dough consistency. Use of high levels of fungal The use and effects of improving agents amylase in the BFP would not be desirable, as potassium bromate, ascorbic acid, azodicarbon the dough softening effect would be too severe. amide, L-cysteine have been discussed in Hence, addition of fungal amylase at these high Ch. 7 levels is made by the baker, and not at the mill the early part of the baking process, attacking Physical treatments gelatinized starch granules, improving gas reten The breadmaking quality of flour can be tion, and helping the dough to maintain a fuid improved also by physical means, e.g. by controlled condition, thus prolonging the dough expansion heat treatment (cf. p. 113) or by an aeration time and increasing loaf volume The increase in process, in which four is whipped with water at loaf volume is directly related to the level of fungal high speed for a few minutes and the batter then amylase addition up to about 200 Farrand Units. mixed with dry flour Improvement is brought The effect of the addition of about 120 farrand about by oxidation with oxygen in the air, prob Units of fungal amylase is so powerful that it may ably assisted by the lipoxidase enzymes (cf
196 TECHNOLOGY OF CEREALS pasta foods, pet foods, dietary foods and textured permit the use of flour of up to 2% lower protein vegetables products (t .v. p. ) . content with no loss in loaf quality. The origin of the gluten is of little importance A similar increase in loaf volume could be when used to raise the flour protein content by produced by addition of a variety of commercial only 1-2%: thus, U.K.-grown wheat can be used carbohydrase enzyme preparations (Cauvain and to provide vital gluten, thereby further reducing Chamberlain, 1988). the dependence on imported strong wheat. The Soya flour vital gluten is generally added to the flour at the mill, particularly in the case of wholemeal. (McDermott, 1985). Enzyme-active soya flour is widely used as a bread additive, at a level of about 0.7% on flour wt. Advantages claimed for its use include: beneficial oxidizing effect on the flour, bleaching Gluten flour This is a blend of vital wheat gluten with wheat effect on flour pigments @-carotene) due to the flour, standardized to 40% protein content in the presence of lipoxygenase, increase in loaf volume, U.S.A. improvement in crumb firmness and crust appearance, and extension of shelf life (Anon., 1988a) (cf. p. 215) The improving action and bleaching properties Fungal amylase Besides the use of low levels (e.g. 7-10 Farrand of enzyme-active soya flour are due to peroxy Units) of fungal amylase to correct a deficiency radicals that are released by a type-2 lipoxygenase, in natural cereal alpha-amylase and improve gas- which has an optimum activity at pH 6.5. Enzymesing (cf. p. 198), fungal amylase, sold under such active soya flour has two effects in a flour dough: trade names as MYL-X and Amylozyme, has a it increases mixing tolerance, and it improves marked effect in increasing loaf volume when used dough rheology, viz. by decreasing extensibility at much higher levels as a bread ingredient in rapid and increasing resistance to extension. The action breadmaking systems. Use of high levels is possible of the lipoxygenase is to oxidize the linoleic acid because the fungal amylase has a relatively low in the lipid fraction of the wheat flour, but the thermal inactivation temperature. The fungal action only occurs in the presence of oxygen amylase starts to act during the mixing stage, (Grosch, 1986). when it causes a softening of the dough, which must be corrected by reducing the amount of Improving agents doughing water, so as to maintain the correct dough consistency. Use of high levels of fungal The use and effects of improving agents - amylase in the BFP would not be desirable, as potassium bromate, ascorbic acid, azodicarbonthe dough softening effect would be too severe. amide, L-cysteine - have been discussed in Hence, addition of fungal amylase at these high Ch. 7. levels is made by the baker, and not at the mill. Physical treatments The fungal amylase continues to act during the early part of the baking process, attacking gelatinized starch granules, improving gas reten- The breadmaking quality of flour can be tion, and helping the dough to maintain a fluid improved also by physical means, e.g. by controlled condition, thus prolonging the dough expansion heat treatment (cf. p. 113) or by an aeration time and increasing loaf volume. The increase in process, in which flour is whipped with water at loaf volume is directly related to the level of fungal high speed for a few minutes and the batter then amylase addition up to about 200 Farrand Units. mixed with dry flour. Improvement is brought The effect of the addition of about 120 Farrand about by oxidation with oxygen in the air, probUnits of fungal amylase is so powerful that it may ably assisted by the lipoxidase enzymes (cf
READ-BAKING TECHNOLOGY 197 p. 68) present in the flour. A similar improving protein)in the grist- which is uneconomic, the effect can be obtained by overmixing normal most convenient way of increasing water absorp- dough(without the batter stage ) cf. the Chorley- tion is to increase the degree of starch damage wood Bread Process(p. 203) The miller can bring this about by modifying the milling conditions(cf. p. 149) Doughmaking Water absorption The enzymes principally concerned in panary The amount of water to be mixed with four fermentation are those that act upon carbohydrates to make a dough of standard consistency is usually alpha-amylase and beta-amylase in flour, and 55-61 pt per 100 pt of four, increasing in maltase, invertase and the zymase complex in yeast proportion to the contents of protein and damaged Zymase is the name that was formerly used for starch(cf. pp 62, 174)in the flour. about fourteen enzymes Flour contains protein, undamaged starch The starch of the four is broken down to the nules and damaged starch granules, all of disaccharide maltose by the amylase enzymes; the which absorb water, but to differing degrees. maltose is split to glucose(dextrose)by maltase; Farrand( 1964) showed that the uptake of water, glucose and fructose are fermented to carbon per gram of component, was 2.0 g for protein, dioxide and alcohol by the zymase complex damaged starch. Thus, flours from strong wheat mechanically damaged during milling(cf ppe g 0-0.3 g for undamaged starch, and Some of the starch granules in four becom (with higher protein content) and from hard 149, 185),and only these damaged granules can wheat(with a higher damaged starch content) be attacked by the flour amylases. It is therefore require more water than is needed by flours from essential that the flour should contain adequate weak(lower protein)or soft(less damaged starch) damaged starch to supply sugar during fermenta- wheats to make a dough of standard consistency. tion and proof. When the amylase enzymes break Besides the protein and starch, the soluble part down the damaged starch, water bound by the of the hemicellulose(pentosan) forming the walls starch is released and causes softening of the of the endosperm cells also absorbs water. dough. This situation must be borne in mind The water used in dough-making should have when calculating the amount of doughing water the correct temperature so that, taking account required, the amount of water released being ar temperature dependent not only on the level of damaged temperature rise during mixing, the dough is starch, but also on the alpha-amylase activity made to the correct final temperature. When length of fermentation time, and dough tempera using a process such as the CBP(cf. p 203)in ture. Excessive levels of starch damage, however which the temperature rise during mixing may have an adverse effect on the quality of the bread be as much as 14C, it may be necessary to cool (cf. p. 150): loaf volume is decreased, and the the doughing water. bread is less attractive in appearance It is important, particularly in plant bakeries, There are small quantities of sugar naturally to maintain constant dough consistency. This present in four(cf p. 55)but these are soon used may be done by adjusting the level of water up by the yeast, which then depends on the sugar addition automatically or semi-automatically. produced by diastatic action from the starch Determination of water absorption of the flour by During fermentation about 0. 8 kg of alcohol is means of the Brabender Farinograph is described produced per 100 kg of flour, but much of it is driven off during the baking process. New bread A four with high water absorption capacity is is said to contain about 0. 3% of alcohol. Secondary generally preferred for breadmaking. Apart from products, e.g. acids, carbonyls and esters, may ncreasing the proportion of strong wheat(high affect the gluten or impart flavour to the bread
BREAD-BAKING TECH NO LOGY 197 p. 68) present in the flour. A similar improving protein) in the grist - which is uneconomic, the effect can be obtained by overmixing normal most convenient way of increasing water absorpdough (without the batter stage): cf. the Chorley- tion is to increase the degree of starch damage. wood Bread Process (p. 203). The miller can bring this about by modifying the milling conditions (cf. p. 149). Doughmaking Fermentation The enzymes principally concerned in panary Water absorption The amount of water to be mixed with flour fermentation are those that act upon carbohydrates: to make a dough of standard consistency is usually alpha-amylase and beta-amylase in flour, and 55-61 pt per 100 pt of flour, increasing in maltase, invertase and the zymase complex in yeast. proportion to the contents of protein and damaged Zymase is the name that was formerly used for starch (cf. pp. 62, 174) in the flour. about fourteen enzymes. Flour contains protein, undamaged starch The starch of the flour is broken down to the granules and damaged starch granules, all of disaccharide maltose by the amylase enzymes; the which absorb water, but to differing degrees. maltose is split to glucose (dextrose) by maltase; Farrand (1964) showed that the uptake of water, glucose and fructose are fermented to carbon per gram of component, was 2.0 g for protein, dioxide and alcohol by the zymase complex. 0-0.3 g for undamaged starch, and 1.0 g for Some of the starch granules in flour become damaged starch. Thus, flours from strong wheat mechanically damaged during milling (cf. pp. 62, (with higher protein content) and from hard 149, 185), and only these damaged granules can wheat (with a higher damaged starch content) be attacked by the flour amylases. It is therefore require more water than is needed by flours from essential that the flour should contain adequate weak (lower protein) or soft (less damaged starch) damaged starch to supply sugar during fermentawheats to make a dough of standard consistency. tion and proof. When the amylase enzymes break Besides the protein and starch, the soluble part down the damaged starch, water bound by the of the hemicellulose (pentosan) forming the walls starch is released and causes softening of the of the endosperm cells also absorbs water. dough. This situation must be borne in mind The water used in dough-making should have when calculating the amount of doughing water the correct temperature so that, taking account required, the amount of water released being of the flour temperature and allowing for any dependent not only on the level of damaged temperature rise during mixing, the dough is starch, but also on the alpha-amylase activity, made to the correct final temperature. When length of fermentation time, and dough temperausing a process such as the CBP (cf. p. 203) in ture. Excessive levels of starch damage, however, which the temperature rise during mixing may have an adverse effect on the quality of the bread be as much as 14"C, it may be necessary to cool (cf. p. 150): loaf volume is decreased, and the the doughing water. bread is less attractive in appearance. It is important, particularly in plant bakeries, There are small quantities of sugar naturally to maintain constant dough consistency. This present in flour (cf. p. 55) but these are soon used may be done by adjusting the level of water up by the yeast, which then depends on the sugar addition automatically or semi-automatically. produced by diastatic action from the starch. Determination of water absorption of the flour by During fermentation about 0.8 kg of alcohol is means of the Brabender Farinograph is described produced per 100 kg of flour, but much of it is on p. 186. driven off during the baking process. New bread A flour with high water absorption capacity is is said to contain about 0.3% of alcohol. Secondary generally preferred for breadmaking. Apart from products, e.g. acids, carbonyls and esters, may increasing the proportion of strong wheat (high affect the gluten or impart flavour to the bread
TECHNOLOGY OF CEREALS rom Aspergillus oryzae or A. awamori, to the flour Both alpha- and beta-amylases catalyze the (cf. p. 196). Fungal amylase is preferred to malt flour because the thermal inactivation temperature hydrolysis of starch, but in different ways(cf p. of fungal amylase is lower (75.C) than that of 67) Normal four from sound wheat alpha-amylase. The amount of alpha-amylase, the consequent difficulties in slicing bread with however,increases considerably when wheat a sticky crumb Gas retention is a property of the flour protein germinates. Indeed, flour from wheat containing the gluten, while being sufficiently extensible to many sprouted grains may have too high an alpha- allow the loaf to rise, must yet be strong enough to prevent gas escaping too readily, as this would nB, some of the starch is changed into dextrin-like lead to collapse of the loaf. The interaction of he crumb is weakened, and the dextrins make the crumb sticky(cf. p 67). However, flour with too powerful effect on gas retention high a natural alpha-amylase activity could be used for making satisfactory bread by microwave Dough development or radio-frequency baking methods(cf. p. 206) Another possibility would be to make use of an Protein alpha-amylase inhibitor, e.g. one prepared from The process of dough development, which barley, as described in Canadian Patent No 1206157 of 1987(Zawistowska et al. 1988). occurs during dough ripening, concerns the The functions of starch in the baking of bread hydrated protein component of the flour. It are to dilute the gluten to a desirable consistenc involves an uncoiling of the protein molecules to provide sugar through diastasis, to provide a and their joining together, by cross-linking, to strong union with gluten, and by gelatinization form a vast network of protein which is collec- to become flexible and to take water from the tively called gluten. The coils of the protein gluten, a process which helps the gluten film to molecules are held together by various types of et and become rigid bonds, including disulphide(Ss-) bonds, and it is the severing of these bonds -allowing the molecule to uncoil- and their rejoining in Gas production and gas retention different positions linking separate protein molecules together that constitutes a major The creation of bubble structure in the dough part of dough development is a fundamental requirement in breadmaking Sulphydryl (SH) groups(cf. pp 66, 174)are The carbon dioxide generated by yeast activity also present in the protein molecules as side groups does not create bubbles: it can only inflate gas of the amino acid cysteine. Reaction between the cells already formed by the incorporation of air -SH groups and the-SS-bonds permits new inter- during mixing and intra-protein/polypeptide relationships to be equate gas must be produced during fermen- formed via-Ss-bonding, one effect of this inter- tation, otherwise the loaf will not be inflated suf- change being the relaxation of dough by the relief ficiently Gas production depends on the quantity of stress induced by the mixing process of soluble sugars in the flour, and on its diastatic While gluten is important in creating an extens- power. Inadequate gassing (maltose value less ible framework, soluble proteins in the dough than 1.5) may be due to an insufficiency of liquor may also contribute to gas retention by damaged starch or to a lack of alpha-amylase; the forming an impervious lining layer within cells latter can be corrected by adding sprouted wheat effectively blocking pin- holes in cell walls( Gar to the grist, or malt four, or fungal amylase, e.g. et al., 1990)
198 TECHNOLOGY OF CEREALS Amylase from Aspergillus oryzae or A. awamori, to the flour (cf. p. 196). Fungal amylase is preferred to malt flour because the thermal inactivation temperature cereal alpha-amylase (87"C), and its use avoids the the consequent difficulties in slicing bread with a sticky crumb. Gas retention is a property of the flour protein: the gluten, while being sufficiently extensible to to prevent gas escaping too readily, as this would lead to collapse of the loaf. The interaction of added fat with flour components also has a powerful effect on gas retention. Dough development Protein The process of dough development, which occurs during dough ripening, cOncernS the hydrated protein component of the flour. It involves an uncoiling of the protein molecules and their joining together, by cross-linking, to form a vast network of protein which is collectively called gluten. The coils of the protein molecules are held together by various types of it is the severing of these bonds - allowing the molecule to uncoil - and their rejoining in different positions - linking separate protein molecules together - that constitutes a major part of dough development. Sulphydryl (-SH) groups (cf. pp. 66, 174) are also present in the protein molecules as side groups of the amino acid cysteine. Reaction between the -SH groups and the -SS- bonds permits new interand intra-proteidpolypeptide relationships to be formed via -SS- bonding, one effect of this interchange being the relaxation of dough by the relief of stress induced by the mixing process. While gluten is important in creating an extensible framework, soluble proteins in the dough liquor may also contribute to gas retention by forming an impervious lining layer within cells, effectively blocking pin-holes in cell walls (Gan et al., 1990). Both alpha- and beta-amylases catalyze the hydro1ysis Of starch, but in different ways (cf' P' of fungal amylase is lower (75°C) than that of 67). beta-amylase but generally only a small amount of alpha-amylase. The amount of alpha-amylase, however, increases considerably when wheat germinates. Indeed, flour from wheat containing amylase activity, with the result that, during baking, some of the starch is changed into dextrin-like substances. Water-holding capacity is reduced, the crumb is weakened, and the dextrins make the crumb sticky (cf. p. 67). However, flour with too high a natural alpha-amylase activity could be used for making satisfactory bread by microwave or radio-frequency baking methods (cf. p. 206). Another possibility would be to make use of an alpha-amylase inhibitor, e.g. one prepared from barley, as described in Canadian Patent No. 1206157 of 1987 (Zawistowska et al., 1988). The functions of starch in the baking of bread are to dilute the gluten to a desirable consistency, to provide sugar through diastasis, to provide a strong union with gluten, and by gelatinization to become flexib1e and to take water from the set and become rigid. Norma1 flour from sound wheat contains amp1e formation of gummy dextrins during baking and many 'prouted grains may have too high an alpha- allow the loaf to rise, must yet be strong enough gluten, a process which he1ps the gluten fi1m to bonds, including disulphide (-SS-) bonds, and Gas production and gas retention The creation of bubble structure in the dough is a fundamental requirement in breadmaking. The carbon dioxide generated by yeast activity does not create bubbles: it can only inflate gas cells already formed by the incorporation of air during mixing. Adequate gas must be produced during fermentation, otherwise the loaf will not be inflated sufficiently. Gas production depends on the quantity of soluble sugars in the flour, and on its diastatic power. Inadequate gassing (maltose value less than 1.5) may be due to an insufficiency of damaged starch or to a lack of alpha-amylase; the latter can be corrected by adding sprouted wheat to the grist, or malt flour, or fungal amylase, e.g
BREAD-BAKING TECHNOLOGY of which those that affect proteins, the proteolyt A dough undergoing fermentation, with inter- enzymes, may be of importance in baking.Yeast mittent mechanical manipulation, is said to be contains such enzymes, but they remain within ripening. The dough when mixed is sticky, but he yeast cells and hence do not influence the as ripening proceeds, it becomes less sticky and gluten The proteolytic enzymes of four are proteases more rubbery when moulded, and is more easily They have both disaggregating and protein handled on the plant. The bread baked from it solubilizing effects, although the two phenomena becomes progressively better, until an optimum may be due to distinct enzymes condition of ripeness has been reached If ripening The undesirable effect on bread quality of flour is allowed to proceed beyond this point a deteriora tion sets in, the moulded dough gets shorter and milled from wheat attacked by bug(cf. p. 9) possibly sticky again, and bread quality becomes is generally considered to be due to excessive poorer.A ripe dough has maximum elasticity proteolytic activity. Inactivation temperature is after moulding and gives maximum spring in the lower for proteolytic enzymes than for diastatic oven; a green or underripe dough can be stretched enzymes, and heat treatment has been recom but has insufficient elasticity mended as a remedy for excessive proteolytic overripe dough tends to break when stretched activity in buggy wheat flour. However, it is difficult to inactivate enzymes by heat treat If the optimum condition of ripeness persists ment without damaging the gluten proteins over a reasonable period of time the flour is to have good fermentation tolerance. Weak flours simultaneously quickly reach a relatively poor optimum, and have poor tolerance, whereas strong flours give Surfactants a higher optimum, take longer to reach it, and These substances act as dough strengtheners, to have good tolerance. Addition of improvers or help withstand mechanical abuse during proces- oxidizing agents to the flour can speed up the rate sing, and they also reduce the degree of retro- at which dough ripens and hence shorten the time gradation of starch(cf. pp. 62 and 209). They taken to achieve optimum developme include calcium and sodium stearoyl lactylate (CSL, SSL and mono- and di-acetyl tartaric Dough stickiness esters of mono- and di-glycerides of fatty acids (DATEM), and are used at levels of about 0.5% disease resistance in wheat have been achieved on flour wt (Hoseney, 1986). The Bread and by incorporating genes from rye. The short arn Flour Regulations 1984 permit the use of SSL of the rye chromosome IR has been substituted up to a maximum of 5 g/kg of bread, in all bread for the short arm of the homologous group 1 and of DatEM esters, with no limit specified chromosome of wheat. However, the doughs in all bread made from the four of many of the substitution lines have a major defect in that they are intensely Stearoyl-2-/actylates sticky. This stickiness is not due to overmixing, Calcium stearoyl-2-lactylate(CSL)and sodium excess water or excess amylolytic activity: the factor responsible for the stickiness, introduced stearoyl-2-lactylate(SSL) are the salts of the with the rye chromosome, has not yet been reaction product between lactic and stearic acids identified(Martin and Stewart, 1991) CSL (Verv')and ssl (Emplex') are dough improving and anti-staling agents; they increase Proteolytic enzymes gas retention, shorten proving time and increase loaf volume. They increase the tolerance of dough Besides the enzymes that act on carbohydrates, to mixing, and widen the range over which good there are many other enzymes in flour and yeast, quality bread can be produced The use of CSL
BREAD-BAKING TECHNOLOGY 199 of which those that affect proteins, the proteolytic enzymes, may be of importance in baking. Yeast contains such enzymes, but they remain within the yeast cells and hence do not influence the gluten. The proteolytic enzymes of flour are proteases. They have both disaggregating and protein solubilizing effects, although the two phenomena may be due to distinct enzymes. The undesirable effect on bread quality of flour milled from wheat attacked by bug (cf. p. 9) is generally considered to be due to excessive proteolytic activity. Inactivation temperature is lower for proteolytic enzymes than for diastatic enzymes, and heat treatment has been recommended as a remedy for excessive proteolytic activity in buggy wheat flour. However, it is difficult to inactivate enzymes by heat treatment without damaging the gluten proteins simultaneously. Surfactants Dough ripening A dough undergoing fermentation, with intermittent mechanical manipulation, is said to be ripening. The dough when mixed is sticky, but as ripening proceeds, it becomes less sticky and more rubbery when moulded, and is more easily hand1ed On the plant’ The bread baked from it becomes progressively better, until an optimum condition of ripeness has been reached. If ripening is allowed to proceed beyond this point a deterioration sets in, the moulded dough gets shorter and possibly sticky again, and bread quality becomes poorer. A ripe dough has maximum elasticity after moulding and gives maximum spring in the oven; a green or underripe dough can be stretched but has insufficient elasticity and spring; an overripe dough tends to break when stretched. If the optimum condition of ripeness persists over a reasonable period of time the flour is said to have good fermentation tolerance. Weak flours quickly reach a relatively poor optimum, and have poor tolerance, whereas strong flours give a higher optimum, take longer to reach it, and oxidizing agents to the flour can speed up the rate at which dough ripens and hence shorten the time taken to achieve optimum development. Do ugh stickiness Certain agronomic advantages and improved disease resistance in wheat have been achieved by incorporating genes from rye. The short arm of the rye chromosome 1R has been substituted for the short arm of the homologous group 1 chromosome of wheat. However, the doughs made from the flour of many of the substitution lines have a major defect in that they are intensely sticky. This stickiness is not due to overmixing, excess water or excess amylolytic activity: the factor responsible for the stickiness, introduced with the rye c~romosome, has not yet been identified (Martin and Stewart, 1991). Proteolytic enzymes Besides the enzymes that act on carbohydrates, there are many other enzymes in flour and yeast, These substances act as dough strengtheners, to sing, and they also reduce the degree of retrogradation of starch (cf. pp. 62 and 209). They include calcium and sodium stearoyl lactylates (CSL, SSL) and mono- and di-acetyl tartaric esters of mono- and di-glycerides of fatty acids (DATEM), and are used at levels of about 0.5% On flour Wt (HoseneY, 1986). The Bread and Flour Regulations 1984 Permit the use of SSL, UP to a maximum of 5 g/kg of bread, in all bread, and of DATEM esters, with no limit specified, in a11 breadStearoy/-Z-/acty/ates Calcium stearoyl-2-lactylate (CSL) and sodium stearoY1-2-1actY1ate (SSL) are the salts of the reaction product between lactic and stearic acids. CSL (‘Verv’) and SSL (‘Emplex’) are dough improving and anti-staling agents; they increase gas retention, shorten proving time and increase loaf volume. They increase the tolerance of dough to mixing, and widen the range over which goodquality bread can be produced. The use of CSL have good to1erance* Addition Of improvers Or help withstand mechanical abuse during proces-