Effect of fat-type on cookie dough and cookie quality Jissy Jacob, K. Leelavathi * Flour Milling, Baking and Confectionery Technology, Central Food Technological Research Institute, Mysore 570020, India Received 6 June 2005; accepted 23 January 2006 Available online 10 March 2006 Abstract Effect of four different fat types on the rheology of the cookie dough and subsequently their effect on the quality of cookies were stud- ied. The dough containing sunflower oil had the least initial farinograph consistency while that containing the bakery fat (‘marvo’) had the most consistency. Observation of the response of the above two cookies doughs to farinograph mixing showed that the one contain- ing the oil showed more resistance to mixing while the other containing the bakery fat decreased in its consistency denoting the softer nature of the later. The cookies containing the oil had relatively higher spread value than the others. While the cookies containing the non-emulsified hydrogenated fat (‘dalda’) had the least spread. Studies also showed that the cookies containing the oil started to spread earlier and continued to spread for a longer time. Cookies containing oil had relatively harder texture and probably so because of the poor entrapment of air during creaming. However, the quality of these cookies was significantly improved by including 0.5% sodium steroyl lactylate in the formulation. Keywords: Cookies; Shortening; Fat; Set-time; Cookie spread; Farinograph consistency 1. Introduction Fat forms one of the basic components of a cookie for- mulation and is present at relatively high levels. Fat acts as a lubricant and contributes to the plasticity of the cookie dough (Maache-Rezzoug, Bouvier, Allaf, & Patras, 1998). It also prevents excessive development of the gluten proteins during mixing. Fat imparts desirable eating qual- ities and contributes to texture and flavour of the product. The addition of shortening is done principally to stabilize air cells that are generated by mixing (Given, 1994). Fat influences the dough machinability during processing, the dough sp read after cutting out, and textural and gustatory qualities of the biscuits after baking ( Vettern, 1984). Pres- ence of fat contributes to the reduction of elastic nature of dough and shrinking of the dough during moulding (Maache-Rezzoug et al., 1998). The type and amount of fat added to the dough has a strong effect on the viscoelas- tic properties (Baltsavias, Jurgens, & van Vliet, 1997). Baltsavias et al. (1997) also reported that reducing the fat content or substituting liquid oil for solid caused a marked decrease in the stiffness of the dough which implies that fat is a crucial structure component. Increasing the level of fat in short doughs has a softening effect on the consistency of the dough (Miller, 1985). The shortening that are used in bakery products range in their consistency from liquid oils to high melting point plastic fats. The only difference between a fat and an edible oil is that at ambient temperature, a fat is semi-solid, and appears more or less firm to the touch, and an oil is in liquid form. They are both of similar chemical composition (Manley, 1998). In cookie production plastic shortening is creamed with sugar to incorporate air bubbles that are trapped in the liquid phase of the shortening. Shortening to be effective must possess ‘plastic’ properties which are in turn exemplified by the correct solid-to-liquid index at dough mixing temperature. Solid fat index (SFI) denotes the proportion of solid to liquid fat in a shortening at a given temperature and has an important relationship to the performance of the product at that temperature. High SFI shortenings do not have enough oil volume for adequate aeration, and low SFI shortenings do not have the ability to hold the air until mixing is complete (O’Brien, 2004). The presence of some solid fat during mixing is thought to be essential and the use of liquid oil is reported to have adverse changes in the handling characteristics of the dough (Abboud, Rubenthaler, & Hoseney, 1985). Another characteristics of fat is its crystalline nature. The three basic polymorphs are designated a, b and b’(Bailey, 1950). It is essential for the fat to be in the b’ crystal form to promote optimum creaming (Baldwin, Baldry, & Johan- sen, 1972). Utilization of emulsified bakery shortening helps in the fine dispersion of the fat in the batter or dough system as compared to non-emulsified shortenings (Pyler, 1988). The main objective of the present work was to study the effect of four such commercially available fats on cookie quality. The fats selected were, an emulsified bakery fat ‘‘marvo’’, specially designed for cookie and biscuit produc- tion; margarine, an emulsified fat manufactured to resem- ble butter; a non-emulsified hydrogenated vegetable fat ‘‘dalda’’, and a non-emulsified refined sunflower oil. Refined sunflower oil was selected because of its high nutri- tional value. Sunflower oil seeds are rich source of linoleic acid, which is one of the nutritionally essent ial fatty acids. The study included the effect of these four type of fats on the rheology of the cookie dough and consequently on the quality of the cookies. 2. Materials and methods 2.1. Mater ials Commercially available refined wheat flour was used for the preparation of sugar-snap cookies. Four types of commercially available fats were used in the formulation. These were, an emulsified bakery shortening ‘marvo’ (M/s. Hindustan Lever Ltd., India), an emulsified marga- rine (M/s. Hindustan Lever Ltd., India), non-emulsified vegetable hydrogenated fat -‘dalda’ (manufactured by Bunge Agribusiness Pvt, Ltd., India), and sunflower oil (ITC Agrotech Ltd., India). Commercially available sugar powder, non-fat dry milk (NFDM), and food grade sodium chloride, dextrose, sodium steroyl lactylate (SSL ), sodium bicarbonate and ammonium chloride were used in the formulation. 2.2. Methods 2.2.1. Chemical and rheological characteristics of wheat flour Wheat flour was analyzed for moisture (44–19), ash (08– 01), protein (46–12), gluten (38–10), falling number (56– 81b), diastatic activity (76–0A), and Farinograph water absorption (54–21) according to standard AACC proce- dures (1995). 2.2.2. Rheological characteristic of cookie dough Cookie dough was prepared in a Hobart mixer accord- ing to AACC micro method (10–52, 1995). The cookie for- mulation consisted of wheat flour 40.0 g, sugar powder 24.0 g, shortening 12.0 g, NFDM 1.20 g, sodium bicarbon- ate 0.32 g, ammonium chloride 0.20 g, sodium chloride 0.18 g and water according to requirement. Consistency of the cookie dough as influenced by different types of fats was measured using Brabender Farinograph according Olewnik and Kulp (1984). Three hundred grams capacity mixer bowl was used in the experiment and the third lever position was used to measure the cookie consistency. The mixing speed of the farinograph was 61 rpm. Three hun- dred grams of the pre-mixed cookie dough was transferred to the farinograph bowl and the farinograph was run for 10 min. Cookie dough consistency was recorded at 0 and 10 min mixing periods respectively. The above experiments were condu cted at ambient temperatures. 2.2.3. Texture of the cookie dough The textural characteristics of the cookie dough were measured in ‘Instron’ Unive rsal Testing machine (Model 4301) using an aluminum plunger with 6.0 cm diameter. The load cell used was 50 kg and the crosshead speed was 10 mm/min with a clearance of 1.5 cm. Cookie dough piece of 4 cm diameter and 1 cm height was used to mea- sure the texture. The force required to compress the dough by 80% was recorded and the average value of six replicates is reported. The above experiments were conducted at ambient temperatures. 2.2.4. Cookie preparation and evaluation Cookies containing four different fats respectively were prepared according to AACC micro method (No. 10–52, 1995). The cookie dough was sheeted to a thickness of 0.5 cm and cut using a circular die of 6.5 cm diameter. Cookies were baked at 205 °C. Cookies were subjectively evaluated for thickne ss, spread, spread ratio, texture and surface cracking patte rn. The breaking strength was mea- sured using the triple beam snap technique of Gains (1991) using ‘Instron’ Universal Testing machine (Model 4301) at a crosshead speed of 50 mm/min and load cell of 250 kg. Force required to break a single cookie was recorded and the average value of six replicates is reported. 2.2.5. Statistical analysis The results were analyzed statistically using Duncan’s New Multiple Range Test (Duncan, 1955). 3. Results and discussion The refined wheat flour used in the study had moisture content of 11.9% and protein content of 9.7% respectively. The flour had an ash content of 0.43% and dry gluten con- tent of 7.13%. The falling number of the flour was 439 s and the diastatic activity was 408 g maltose/10 g flour. Flour had Farinograph water absorption of 59.6%. 3.1. Measur ement of the cookie dough consistency The farinograph dough consistency and the farinograph bandwidth of the pre-mixed cookie dough were recorded at 0 and 10 min mixing respectively (Table 1 and Fig. 1). The horizontal position of the band on the chart is considered a measure of consistency (resistance to movement), with lar- ger numbers (BU) indicating stiffer dough and the band- width is considered to denote the degree of tenacity properties of doughs (Olewnik & Kulp, 1984). The result showed that the cookie dough containing the sunflower oil had the least initial consistency of 200 BU, which increased to 400 BU with continued mixing in the farino- graph. The initial bandwidth of this farinogram was rela- tively narrow at 20 BU. With continued mixing however, the bandwidth increased to 120 BU. This denotes that the dough containing the oil, even though, was less stiff ini- tially, became relatively more stiff and tenacious with con- tinued mixing. Subjective observation during dough preparation showed that mixing of oil, sugar and water formed a very smooth and less aerated thin paste and when flour was added to the above cream it transformed into dough quite easily. Olewnik and Kulp (1984) infer that physical properties of coo kie dough depend on the distri- bution of fat and water in the system and when fat is poorly distributed in the cookie system flour particles remain accessible to water which results in development of gluten proteins. Maache-Rezzoug et al. (1998) explain that it is only when fat is mixed with flour before hydration, that it prevent s the formation of a gluten network and produce less elastic dough. When liquid oils are used in a dough sys- tem it gets dispersed on mixing through out the dough in the form of minutes globules which are far less effective in their shortening and aerative actions than are plastic fat films (Pyler, 1988). It is possible that when sunflower oil was used in the present study, it lacked the ability to smear all the flour particles and therefore had the tendency for gluten protein to develop during the mixi ng resulting in an increase in the consistency of the dough. Development of gluten proteins would also make the dough elastic, which offers resistance to mixing resulting in wider band width. It can also be speculated here that the cookie dough containing oil was less aerated becau se unlike the solid or plastic fats liquid oil do not aid in aeration of the dough or batter in which they are present (Pyler, 1988). Dough density depends on the type of fat used. Less aerated dough is denser than aerated dough resulting in stiffer dough consistency. It is believed that the solid content of the fat at mixing affects dough density, doughs with lower solid fat have higher densities (Baltsavias et al., 1997). Cookie dough containing the non-emulsified hydroge- nated fat (‘dalda’) had an initial consistency of 310 BU and the consistency did not change much even after 10 min mixing. The bandwidth of the above farinogram was 60 BU at 0 min and increased marginally to 80 BU at the end of 10 min mixing. The above observation showed that the dough was relatively stiff and maintained its consistency even after 10 min mixing in the farinograph. This could be due to the fact that hard fats when used in a dough system solidify into undesirable b crystalline form that do not aid in proper aeration resulting in dense and stiff dough (Knightly, 1981). O’Brien, Chapman, Neville, Keogh, and Arendt (2003) also reported that hydrogenated vegetable fats produced very stiff biscuit dough. Baltsavias et al. (1997) explained that a firm fat will be broken down to large lumps, whereas the standard fat will be smeared out over the flour particles. Another draw back of this fat was the absence of an emulsifier in its system. An emul- sifier is able to trap air and improve the creaming property of the dough or batter system (O’Brien, 2004). A well aer- ated dough is less stiff than a poorly aerated dough. Incor- poration of mono- and di-glycerides reduces the dependence of shortenings upon the crystalline properties, solids-to-liquid ratios, and mixing procedures to develop creaming properties (O’Brien, 2004). Presence of emulsifi- ers in fat is also highly effective in promoting the uniform dispersion of the fat in dough (Pyler, 1988). Cookie dough containing margarine had an initial con- sistency of 380 BU, but the consistency decreased to 270 BU with further mixing. The bandwidth of the farino- gram was initially 60 BU and did not alter much with mix- ing further. Subjective observation during dough preparation in the Hobart mixer showed that the fat, sugar and water formed a very light, fluffy, well aerated cream Table 1 Effect of fat type on the farinograph consistency of cookie dough Fat type Farinograph dough consistency (BU) 0 (min) 10 (min) Bakery fat (Marvo) 440 360 Margarine 380 270 Hydrogenated fat (dalda) 310 300 Sunflower oil 200 400 Fig. 1. Effect of: (1) bakery fat (marvo), (2) margarine, (3) non-emulsified hydrogenated fat (dalda), and (4) sunflower oil, on Farinograph charac- teristics of cookie dough. and with the addition of flour transformed into a soft dough. Therefore, it is possible that even though the initial consistency of this dough was relatively higher, on further mixing in the farinograph, the consistency of this dough decreased significantly by about 100 BU denoting that the dough became less stiff. In most of the cases processing of margarine is directed at achieving a b’-crystal modifica- tion, which ensures that the fat can readily incorporate and retain air (Hamm & Hamilton, 2004). In addition the mar- garine fat that was used in this study also contained certain emulsifiers, which would further have enhanced the aerat- ing properties of the cream. Due to these reasons the coo- kie dough containing margarine broke down easily when mixed in the Farinograph with a relatively narrow band- width indicating a less elastic dough. Finally, the cookie dough containing the emulsified bak- ery fat ‘‘marvo’’ had an initial consistency of 440 BU, high- est recorded amongst the four fats studied. The consistency however, decreased to 360 BU after 10 min mixing. The ini- tial bandwidth was 80 BU and did not change with mixing the dough further. During manufacture of bakery fats b’ hard fats are added to extend their plastic range which improves their creaming properties, texture and consis- tency (O’Brien, 2004). Even though the initial consistency of this dough was relatively more compared to the other three cookie doughs, the consistency reduced considerably during continued mixing in the farinograph, most probably because the dough was well aerated hence less dense. The narrow bandwidth of the above dough also indicates the non-elastic nature of the dough. This observation was sim- ilar to the one made for the dough containing margarine. It can be argued here that if the initial consistency is taken into consideration, the stiffest of the four doughs was the one containing the bakery fat ‘marvo’ and the soft- est was that containing the oil. However, if their response to mixing is considered, the dough containing oil showed more resistance to mixing maintaining its consistency throughout the mixing period hence the stiffest, while the dough containing both margarine and ‘marvo’ decreased in its consistency denoting they had the least resistance towards mixing hence the least stiff. The dough containing ‘dalda’ could also be considered to be stiff, as it did not break down on continued mixing in the farinograph. If the band width could be related to the tenacious properties of the dough, according to Olewnik and Kulp (1984), even though the initial band width of the dough containing oil was less it increased to abou t 120 BU and maintained its band width. The least tenacious dough was the one con- taining the margarine. The variation in the consistency of the dough containing different fats could be due to the variation in their SFI which is an indication of the actual proportion of the solid component present in a shortening. Plastic shortenings, although exhibit the properties of solids at room tempera- ture are in reality a mixture of both crystalline and liqui d triglycerides in which the liquid oil is enmeshed in a mass of minute fat crystals. The plastic nature of the shortening is influenced by factors such as amount of solid material present, size and form of the individual crystals etc. In ordinary plastic shortening the content of solid fats gener- ally comprises 20–30%, while the remaining 70–80% repre- sent liquid oils (Pyler, 1988). In order for the fat to be effective it should have a correct solids-to-liquid ratio at dough mixin g temperatur e (Given, 1994). 3.2. Texture analysis of cookie dough The force required to compress the co okie dough con- taining four different types of fats respectivel y is shown in Fig. 2. Results show that the cookie dough containing the non-emulsified hydrogenated fat (‘dalda’) was the hard- est requiring more strength to compress it to the required extent. Cookie dough containing ‘margarine’ was the soft- est requiring the least force to compress it. Dough samples containing the bakery fat and sunflower oil respectively had almost similar textural properties that were marginally harder than that containing margarine. It is possible that dough made with oil is generally more cohesive and viscous and hence softer. On the other hand, dough made with hydrogenated fats gives higher values. 3.3. Physica l characteristics of cookies The physical characteristics of cookies made using differ- ent fats are shown in Table 2. The result showed that cook- ies containing sunflower oil had relatively higher spread value. Abboud et al. (1985) had earlier reported that with the use of oil there was a non-significant increase in the diameter of the cookies. Cookies containing margarine and bakery fat (‘Marvo’) respectively had similar spread values. On the other hand, cookie dough containing the hydrogenated fat (‘dalda’) had significantly less spread. Fin- ney, Yamazaki, and Morris (1950) and later Abboud et al. (1985) concluded that fat type is not an important variable for cookie spread. But in the above experi ment it was noted that the cookies containing the non-emulsified hydro- genated fat ‘dalda’ had spread less. The hydrogenated fat Fig. 2. Effect of bakery fat (marvo), margarine, non-emulsified hydroge- nated fat (dalda), and sunflower oil respectively, on cookie dough hardness. tends to form beta crystals which do not support aeration (Knightly, 1981). Partial hydrogenation is applied to help produce vegetable bakery shortenings having desirable plastic character (Given, 1994). 3.4. Measur ement of cookie set time In the present study it was of inter est to observe the set time of the cookie dough containing different fats . The ‘set- time’ is the point at which, expansion of the cookie dough stops (Hoseney, Wade, & Finley, 1988). In order to observe the set time of the cookie dough, the sheeted and cut cookie dough (4.5 cm diameter) was placed in the baking oven maintained at 205 °C. Respective cookie doughs were care- fully removed from the oven at every 1 min interval until the final baking time. The spread of the cookie dough and eventually the cookie was measured at each point of removal. The results are shown in Fig. 3. Accordingly, it was observed that dough containing sunflower oil started to spread earlier than the other doughs and continued to spread for a much longer time until the doug h reached its set point. A high spread rate plus a delayed set time gives the largest diameter to the cookies (Stauffer, 1994). On the other hand, dough containing the hydrogenated fat ‘‘dalda’’ reached its set point much early. Cookie dough containing margarine spread faster initially than that con- taining the bakery fat ‘Marvo’ and reached its set point around 5 min of baking. Cookie dough containing bakery fat ‘Marvo’ spread more gradually. However, the set point for both the dough was around 6 min. 3.5. Measur ement of cookie texture Measurement of the breaking strength showed that cookies containing the oil were the hardest ( Table 2 and Fig. 4). On the other hand, breaking strength of cookies containing the other three types of fats was not signifi- cantly different from each other. It was of interest to observe here that hardness of the dough (Fig. 2) did not necessarily control the texture of the cookies (Fig. 4). As observed earlier cookie dough containing hydrogenated fat was the hardest and the least dough hardness was observed for that containing margarine. The texture of the cookie dough containing sunflower oil was similar to that containing the bakery fat. In contrast, cookies made using sunflower oil were the hardest while those containing the bakery fat were the least hard. Abboud et al. (1985) also reported that it is not possible to obtain a satisfactory creamed mass with oil hence lacking proper aeration. Greethead (1969) claim that more plastic and smooth tex- tured the fat greater its shortening power. Softer the worked fat, lower the breaking strength of the cookies. Plasticity in fats is required since during the creaming pro- cess they entrap and retain considerable volumes of air resulting in an important leavening effect. Ordinary liquid oils on the other hand, are dispersed upon mixing through out the dough in the form of globules that are less effec- tive in their shortening and aerating actions (Hartnett & Table 2 Effect of fat type on the physical characteristics of cookies Fat type Width (W) (cm) Thickness (T) (cm) Spread ratio (W/T) Breaking strength (kg f) Bakery fat (Marvo) 8.1 b 1.08 7.51 4.6 a Margarine 8.1 b 1.10 7.37 4.7 a Hydrogenated fat (dalda) 7.8 c 1.03 7.58 5.1 ab Sunflower oil 8.8 a 1.05 8.38 9.7 c Figures followed by different letters are significantly different from each other (p 6 0.05). 4 5 6 7 8 12345678910 Bakin g time (minutes) Cookie spread (cm) bakery fat margarine hydrogenated fat sunflower oil Fig. 3. Effect of bakery fat (marvo), margarine, non-emulsified hydroge- nated fat (dalda), and sunflower oil respectively, on the rate of cookie spread. 0 2 4 6 8 10 12 Breaking strength (Kg) Bakery fat Margarine Hydrogenated fat Sunflower oil Fig. 4. Effect of bakery fat (marvo), margarine, non-emulsified hydroge- nated fat (dalda), and sunflower oil respectively, on the breaking strength of cookies. Thalheimer, 1979). Hornstein, King, and Benedict (1943) claimed that consistency of the worked fat has a highly sig- nificant effect with softer the worked fat, lower the break- ing strength of the cookie. Kamel (1994) explains that although large amounts of air can be incorporated into liquid oil, it cannot be retained in the system and this might explain the hard texture of the cookie. 3.6. Surface cracking pattern of cookies One of the important features of sugar-snap cookies is their surface cracking pattern. Cookies containing the bak- ery fat had uniform medium sized islands (Fig. 5). Rela- tively smaller islands were seen in cookies containing margarine. Cookies made using the hydrogenated fat ‘dalda’ had still smaller islands. On the other hand, cookies containing the oil had large sized islands. Doescher and Hoseney (1985) explain that during baking, sucrose present on the surface of the cookie crystallizes, causing the surface to dry rapidly and as the cookie spreads, the dry surface cracks. In the present study, it can be recalled that the coo- kie doughs containing the three plastic fats respect ively stopped spreading around 5 min of baking while that con- taining the oil continued to spread till about 7 min of bak- ing. It can be reasoned here that sugar crystallization took place at the appropriate time that led to drying of the coo- kie surface. But since the cookie dough continued to spread because the dough was not sufficiently viscous to stop the spread the hardened surface cracked leading to larger sized islands. 3.7. Replacement of oil with bakery fat Since presence of oil produced cookies which had very large surface islands and hard texture it was of interest to see if partial replacement of oil with the bakery fat would have any impro ving effect on these cookies. Accordingly 50% of oil was replaced with the bakery fat and the cookies were prepared. The results showed that the breaking strength of these cookies reduced significantly to 5.3 kg from 9.7 kg when only oil was used in the formulation (Fig. 6). There was an improvement in the surface islands also (Fig. 7). These islands that were large when only oil was present in the formulation became medium sized and more acceptable with partial replacement with the bakery fat. Partial replacement with a plastic fat was sufficient to aerate the cookie dough during mixing which imparted a significant effect on both the texture and surface islands of the cookies. 3.8. Effect of sodium steroyl lactylate (SSL) on quality of cookies contai ning oil SSL has been demonstrated to contribute to aeration of the dough, improve top grain score and also the viscosity of the cookie dough during baking (Tsen, Bauck, & Hoover, 1975). In the present study 0.5% SSL was included in the cookie formulatio n containing the oil. The results were very significant. The hardness of the cookies reduced significantly (Fig. 6). The hardest of the cookies as was seen earlier were the ones containing the sunflower oil recording a breaking strength of 9.7 kg. When SSL was added this value reduced to 3.5 kg. There was also a significant improvement in the surfa ce cracking pattern of the cookies. The islands on the cookie surface were of medium size instead of the large ones when no emulsifier was used (Fig. 7). There was also a reduction in the spread of the Fig. 5. Effect of (1) bakery fat (marvo), (2) margarine, (3) non-emulsified hydrogenated fat (dalda), and (4) sunflower oil on surface cracking pattern of cookies. Fig. 6. Effect of sunflower oil (SFO), sunflower oil + bakery fat (marvo) (SFO + BF), sunflower oil + SSL (SFO + SSL), respectively, on cookie breaking strength. Fig. 7. Effect of bakery fat (marvo) (2); and SSL (3); on the surface cracking pattern of cookies containing sunflower oil (1). cookies. Incorporation of air cells is known to influence the viscosity of the system. Viscosity of the cookie dough in the oven is known to affect the spread of the cookies and emul- sifiers have the ability to control the viscosity of the dough (Tsen et al., 19 75). Earlier Hodge (1984) had reported that excellent cookies could be made from dough containing relatively low levels of emulsified liquid oils as compared to traditional levels of plastic shortenings. Given (1994) has elucidated that even though emulsified oils do not contain any appreciable solids, they perform as equally well as plastic shortenings with regard to retention of incor- porated air. 4. Conclusions Measurement of cookie dough consistency in farino- graph showed that the one containing the oil behaved dif- ferently than those containing the other three types of fats. This farin ogram looked as though the dough was develop- ing during the initial stages of mixing in the farinograph. And also this dough did not break down during mixing and the farinogram had a relative ly stable and wider ban d. This could be probably because there was more free water in the dough which had not formed an emulsion with the oil. And this free water was being utilized for the develop- ment of the gluten proteins making the dough more elastic and offering more resistance to mixing. On the other hand, doughs containing the plastic fats showed a tendency for break down inferring the relative soft texture of the dough. The measurement of texture of the cookie dough in the texture analyzer revealed that dough containing the hydro- genated fat ‘dalda’, needed more force to compress it than those containing either the sunflower oil or the other two types of fats . Here texture of the cookie dough containing oil was similar to the ones containing the bakery fat. Comparing the above two measurements with the coo- kie texture, the mixing trend of the cookie dough in the far- inograph seem to give a better insi ght into the texture of the cookies rather than its initial consis tency in the farino- graph or the measurement of its compression force in a tex- ture analyzer. References AACC (1995). Approved methods (9th ed.). St. Paul, MN: American Association of Cereal Chemists. Abboud, A. M., Rubenthaler, G. L., & Hoseney, R. C. (1985). 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Manhattan, KS, USA: American Institute of Baking. . farinograph dough consistency and the farinograph bandwidth of the pre-mixed cookie dough were recorded at 0 and 10 min mixing respectively (Table 1 and Fig. 1). The horizontal position of the band on. effect on both the texture and surface islands of the cookies. 3.8. Effect of sodium steroyl lactylate (SSL) on quality of cookies contai ning oil SSL has been demonstrated to contribute to aeration. 2006 Available online 10 March 2006 Abstract Effect of four different fat types on the rheology of the cookie dough and subsequently their effect on the quality of cookies were stud- ied. The dough containing