ing the oil showed more resistance to mixing while the other containing the bakery fat decreased in its consistency denoting the softernature of the later. The cookies containing the oil had relatively higher spread value than the others. While the cookies containing the
dough (Maache-Rezzoug, Bouvier, Allaf, & Patras,1998). It also prevents excessive development of the gluten
of dough and shrinking of the dough during moulding(Maache-Rezzoug et al., 1998). The type and amount of
is a crucial structure component. Increasing the level of fatin short doughs has a softening eect on the consistency of
creamed with sugar to incorporate air bubbles that aretrapped in the liquid phase of the shortening. Shorteningto be eective must possess plastic properties which arein turn exemplied by the correct solid-to-liquid index atdough mixing temperature. Solid fat index (SFI) denotesthe proportion of solid to liquid fat in a shortening at a
* Corresponding author. Tel.: +91 0821 2517730; fax: +91 08212517233.
E-mail address: firstname.lastname@example.org (K. Leelavathi).
Journal of Food Engineering 7proteins during mixing. Fat imparts desirable eating qual-ities and contributes to texture and avour of the product.The addition of shortening is done principally to stabilizeair cells that are generated by mixing (Given, 1994). Fatinuences the dough machinability during processing, thedough spread after cutting out, and textural and gustatoryqualities of the biscuits after baking (Vettern, 1984). Pres-ence of fat contributes to the reduction of elastic nature
the dough (Miller, 1985).The shortening that are used in bakery products range in
their consistency from liquid oils to high melting pointplastic fats. The only dierence between a fat and an edibleoil is that at ambient temperature, a fat is semi-solid, andappears more or less rm to the touch, and an oil is inliquid form. They are both of similar chemical composition(Manley, 1998). In cookie production plastic shortening isnon-emulsied hydrogenated fat (dalda) had the least spread. Studies also showed that the cookies containing the oil started to spreadearlier and continued to spread for a longer time. Cookies containing oil had relatively harder texture and probably so because of thepoor entrapment of air during creaming. However, the quality of these cookies was signicantly improved by including 0.5% sodiumsteroyl lactylate in the formulation. 2006 Elsevier Ltd. All rights reserved.
Keywords: Cookies; Shortening; Fat; Set-time; Cookie spread; Farinograph consistency
Fat forms one of the basic components of a cookie for-mulation and is present at relatively high levels. Fat acts asa lubricant and contributes to the plasticity of the cookie
fat added to the dough has a strong eect on the viscoelas-tic properties (Baltsavias, Jurgens, & van Vliet, 1997).Baltsavias et al. (1997) also reported that reducing the fatcontent or substituting liquid oil for solid caused a markeddecrease in the stiness of the dough which implies that fatEect of fat-type on cooki
Jissy Jacob, K
Flour Milling, Baking and Confectionery Technology, Centra
Received 6 June 2005;Available onlin
Eect of four dierent fat types on the rheology of the cookie doied. The dough containing sunower oil had the least initial farinothe most consistency. Observation of the response of the above two0260-8774/$ - see front matter 2006 Elsevier Ltd. All rights reserved.doi:10.1016/j.jfoodeng.2006.01.058dough and cookie quality
ood Technological Research Institute, Mysore 570020, India
pted 23 January 20060 March 2006
h and subsequently their eect on the quality of cookies were stud-ph consistency while that containing the bakery fat (marvo) hadokies doughs to farinograph mixing showed that the one contain-
9 (2007) 299305
Fogiven temperature and has an important relationship to theperformance of the product at that temperature. High SFIshortenings do not have enough oil volume for adequateaeration, and low SFI shortenings do not have the abilityto hold the air until mixing is complete (OBrien, 2004).The presence of some solid fat during mixing is thoughtto be essential and the use of liquid oil is reported to haveadverse changes in the handling characteristics of thedough (Abboud, Rubenthaler, & Hoseney, 1985). Anothercharacteristics of fat is its crystalline nature. The threebasic polymorphs are designated a, b and b (Bailey,1950). It is essential for the fat to be in the b crystal formto promote optimum creaming (Baldwin, Baldry, & Johan-sen, 1972). Utilization of emulsied bakery shorteninghelps in the ne dispersion of the fat in the batter or doughsystem as compared to non-emulsied shortenings (Pyler,1988).
The main objective of the present work was to study theeect of four such commercially available fats on cookiequality. The fats selected were, an emulsied bakery fatmarvo, specially designed for cookie and biscuit produc-tion; margarine, an emulsied fat manufactured to resem-ble butter; a non-emulsied hydrogenated vegetable fatdalda, and a non-emulsied rened sunower oil.Rened sunower oil was selected because of its high nutri-tional value. Sunower oil seeds are rich source of linoleicacid, which is one of the nutritionally essential fatty acids.The study included the eect of these four type of fats onthe rheology of the cookie dough and consequently onthe quality of the cookies.
2. Materials and methods
Commercially available rened wheat our was usedfor the preparation of sugar-snap cookies. Four types ofcommercially available fats were used in the formulation.These were, an emulsied bakery shortening marvo(M/s. Hindustan Lever Ltd., India), an emulsied marga-rine (M/s. Hindustan Lever Ltd., India), non-emulsiedvegetable hydrogenated fat -dalda (manufactured byBunge Agribusiness Pvt, Ltd., India), and sunower oil(ITC Agrotech Ltd., India). Commercially available sugarpowder, non-fat dry milk (NFDM), and food gradesodium chloride, dextrose, sodium steroyl lactylate (SSL),sodium bicarbonate and ammonium chloride were usedin the formulation.
2.2.1. Chemical and rheological characteristics of wheat our
Wheat our was analyzed for moisture (4419), ash (0801), protein (4612), gluten (3810), falling number (5681b), diastatic activity (760A), and Farinograph water
300 J. Jacob, K. Leelavathi / Journal ofabsorption (5421) 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 (1052, 1995). The cookie for-mulation consisted of wheat our 40.0 g, sugar powder24.0 g, shortening 12.0 g, NFDM 1.20 g, sodium bicarbon-ate 0.32 g, ammonium chloride 0.20 g, sodium chloride0.18 g and water according to requirement. Consistencyof the cookie dough as inuenced by dierent types of fatswas measured using Brabender Farinograph accordingOlewnik and Kulp (1984). Three hundred grams capacitymixer bowl was used in the experiment and the third leverposition was used to measure the cookie consistency. Themixing speed of the farinograph was 61 rpm. Three hun-dred grams of the pre-mixed cookie dough was transferredto the farinograph bowl and the farinograph was run for10 min. Cookie dough consistency was recorded at 0 and10 min mixing periods respectively. The above experimentswere conducted at ambient temperatures.
2.2.3. Texture of the cookie dough
The textural characteristics of the cookie dough weremeasured in Instron Universal Testing machine (Model4301) using an aluminum plunger with 6.0 cm diameter.The load cell used was 50 kg and the crosshead speedwas 10 mm/min with a clearance of 1.5 cm. Cookie doughpiece of 4 cm diameter and 1 cm height was used to mea-sure the texture. The force required to compress the doughby 80% was recorded and the average value of six replicatesis reported. The above experiments were conducted atambient temperatures.
2.2.4. Cookie preparation and evaluation
Cookies containing four dierent fats respectively wereprepared according to AACC micro method (No. 1052,1995). The cookie dough was sheeted to a thickness of0.5 cm and cut using a circular die of 6.5 cm diameter.Cookies were baked at 205 C. Cookies were subjectivelyevaluated for thickness, spread, spread ratio, texture andsurface cracking pattern. The breaking strength was mea-sured using the triple beam snap technique of Gains(1991) using Instron Universal Testing machine (Model4301) at a crosshead speed of 50 mm/min and load cell of250 kg. Force required to break a single cookie wasrecorded and the average value of six replicates is reported.
2.2.5. Statistical analysisThe results were analyzed statistically using Duncans
New Multiple Range Test (Duncan, 1955).
3. Results and discussion
The rened wheat our used in the study had moisturecontent of 11.9% and protein content of 9.7% respectively.The our had an ash content of 0.43% and dry gluten con-tent of 7.13%. The falling number of the our was 439 s
od Engineering 79 (2007) 299305and the diastatic activity was 408 g maltose/10 g our.Flour had Farinograph water absorption of 59.6%.
3.1. Measurement of the cookie dough consistency
The farinograph dough consistency and the farinographbandwidth of the pre-mixed cookie dough were recorded at0 and 10 min mixing respectively (Table 1 and Fig. 1). Thehorizontal position of the band on the chart is considered ameasure of consistency (resistance to movement), with lar-ger numbers (BU) indicating stier dough and the band-width is considered to denote the degree of tenacityproperties of doughs (Olewnik & Kulp, 1984). The resultshowed that the cookie dough containing the sunoweroil had the least initial consistency of 200 BU, whichincreased 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 thedough containing the oil, even though, was less sti ini-tially, became relatively more sti and tenacious with con-tinued mixing. Subjective observation during doughpreparation showed that mixing of oil, sugar and waterformed a very smooth and less aerated thin paste and whenour was added to the above cream it transformed intodough quite easily. Olewnik and Kulp (1984) infer thatphysical properties of cookie dough depend on the distri-bution of fat and water in the system and when fat is poorlydistributed in the cookie system our particles remainaccessible to water which results in development of gluten
J. Jacob, K. Leelavathi / Journal of FoTable 1Eect of fat type on the farinograph consistency of cookie dough
Fat type Farinograph dough consistency(BU)
0 (min) 10 (min)
Bakery fat (Marvo) 440 360Margarine 380 270Hydrogenated fat (dalda) 310 300Sunower oil 200 400
Fig. 1. Eect of: (1) bakery fat (marvo), (2) margarine, (3) non-emulsied
hydrogenated fat (dalda), and (4) sunower oil, on Farinograph charac-teristics of cookie dough.proteins. Maache-Rezzoug et al. (1998) explain that it isonly when fat is mixed with our before hydration, thatit prevents the formation of a gluten network and produceless elastic dough. When liquid oils are used in a dough sys-tem it gets dispersed on mixing through out the dough inthe form of minutes globules which are far less eectivein their shortening and aerative actions than are plasticfat lms (Pyler, 1988). It is possible that when sunoweroil was used in the present study, it lacked the ability tosmear all the our particles and therefore had the tendencyfor gluten protein to develop during the mixing resulting inan increase in the consistency of the dough. Developmentof gluten proteins would also make the dough elastic,which oers resistance to mixing resulting in wider bandwidth. It can also be speculated here that the cookie doughcontaining oil was less aerated because unlike the solid orplastic fats liquid oil do not aid in aeration of the doughor batter in which they are present (Pyler, 1988). Doughdensity depends on the type of fat used. Less aerateddough is denser than aerated dough resulting in stierdough consistency. It is believed that the solid content ofthe fat at mixing aects dough density, doughs with lowersolid fat have higher densities (Baltsavias et al., 1997).
Cookie dough containing the non-emulsied hydroge-nated fat (dalda) had an initial consistency of 310 BUand the consistency did not change much even after10 min mixing. The bandwidth of the above farinogramwas 60 BU at 0 min and increased marginally to 80 BUat the end of 10 min mixing. The above observationshowed that the dough was relatively sti and maintainedits consistency even after 10 min mixing in the farinograph.This could be due to the fact that hard fats when used in adough system solidify into undesirable b crystalline formthat do not aid in proper aeration resulting in dense andsti dough (Knightly, 1981). OBrien, Chapman, Neville,Keogh, and Arendt (2003) also reported that hydrogenatedvegetable fats produced very sti biscuit dough. Baltsaviaset al. (1997) explained that a rm fat will be broken downto large lumps, whereas the standard fat will be smearedout over the our particles. Another draw back of thisfat was the absence of an emulsier in its system. An emul-sier is able to trap air and improve the creaming propertyof the dough or batter system (OBrien, 2004). A well aer-ated dough is less sti than a poorly aerated dough. Incor-poration of mono- and di-glycerides reduces thedependence of shortenings upon the crystalline properties,solids-to-liquid ratios, and mixing procedures to developcreaming properties (OBrien, 2004). Presence of emulsi-ers in fat is also highly eective in promoting the uniformdispersion of the fat in dough (Pyler, 1988).
Cookie dough containing margarine had an initial con-sistency of 380 BU, but the consistency decreased to270 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
od Engineering 79 (2007) 299305 301preparation in the Hobart mixer showed that the fat, sugarand water formed a very light, uy, well aerated cream
is inuenced by factors such as amount of solid materialpresent, size and form of the individual crystals etc. Inordinary plastic shortening the content of solid fats gener-ally comprises 2030%, while the remaining 7080% repre-sent liquid oils (Pyler, 1988). In order for the fat to beeective it should have a correct solids-to-liquid ratio atdough mixing temperature (Given, 1994).
3.2. Texture analysis of cookie dough
The force required to compress the cookie dough con-taining four dierent types of fats respectively is shown inFig. 2. Results show that the cookie dough containingthe non-emulsied hydrogenated fat (dalda) was the hard-est requiring more strength to compress it to the required
Food Engineering 79 (2007) 299305and with the addit...