UTILIZATION OF APRICOT KERNEL FLOUR AS FAT REPLACER IN COOKIES

UTILIZATION OF APRICOT KERNEL FLOUR AS FATREPLACER IN COOKIES

I.T. SEKER1, O. OZBOY-OZBAS2,4, I. GOKBULUT2, S. OZTURK3

and H. KOKSEL3

1Department of Food TechnologyCumhuriyet University

Zara, Sivas, Turkey

2Department of Food EngineeringInönü UniversityMalatya, Turkey

3Department of Food EngineeringHacettepe University

Ankara, Turkey

Accepted for Publication April 16, 2008

ABSTRACT

In this study, shortening content in a wire-cut cookie formulation wasreduced at 10, 20, 30 and 40% and replaced with apricot kernel flour (AKF).The effects of increased concentrations of AKF on the properties of cookieswere investigated. Protein, fat and total dietary fiber (TDF) contents of theapricot kernels were determined as 21.8%, 40.2% and 35.8%, respectively,which confirmed that the apricot kernel is an important source of dietaryprotein as well as oil and fiber. Addition of AKF decreased the spread ratio andincreased the hardness of the cookies (P � 0.01). However, sensory evaluationrevealed that the cookies containing AKF were acceptable to the panelists atall concentrations (P � 0.01). TDF contents of the cookies increased signifi-cantly (P � 0.01) as the AKF supplemention increased. AKF is a suitablereplacer of shortening in cookies at 10 and 20%.

PRACTICAL APPLICATIONS

Province of Malatya (Turkey) is one of the major apricot and apricotkernel producing regions in the world. Apricot kernels are generally exportedand the importing countries use it especially in the production of oil, benzal-

4 Corresponding author. TEL: 90 422 3410010; FAX: 90 422 3410046; EMAIL: [email protected]

Journal of Food Processing and Preservation 34 (2010) 15–26.DOI: 10.1111/j.1745-4549.2008.00258.x 15© 2010 The Author(s)Journal compilation © 2010 Wiley Periodicals, Inc.

dehyde, cosmetics, active carbon and aroma. Apricot kernels are also utilizedin retail bakeries and consumed as appetizers. Cookies are one of the mostpopular bakery products and textural characteristics of cookies are highlyinfluenced by their fat content. Health specialists recommend that daily fatconsumption should not exceed 30% of the total calories in a diet.

In this study, the preparation of apricot kernel flour (AKF), which doesnot require much processing and has the advantage of including other nutri-ents, was achieved. With the production of high-fiber and low-fat cookies bythe usage of AKF, an exciting new potential as a food ingredient, especially incereal products, is offered.

INTRODUCTION

Apricot (Prunus armeniaca L.) is one of the most popular stone fruitsgrown in some regions of Turkey. It can be used as a fresh, dried or processedfruit. Turkey is the biggest apricot producer (538,000 metric tons/year) in theworld (FAO 1998). Most of the apricots are produced in the Malatya region ofTurkey. The most widely produced cultivar is Hacıhaliloglu (Gezer et al.2002).

Apricot kernels, especially rich in lipid and protein, are potentially usefulin human nutrition (Femenia et al. 1995; Iordanidou et al. 1999; Alpaslan andHayta 2006). The chemical and nutritional properties of apricot kernels werestudied in detail by many research groups (Gabrial et al. 1981; Lazos 1991;Aydemir et al. 1993; El-Adawy et al. 1994; Femenia et al. 1995; Iordanidouet al. 1999; Özcan 2000; Özkal et al. 2005; Alpaslan and Hayta 2006). Crudefiber values reported (Gabrial et al. 1981; Aydemir et al. 1993) for apricotkernels were 15.8–18.02% and 18.33%, respectively. Femenia et al. (1995)also reported that oleic and linoleic acid contents of apricot kernels wereapproximately 92 g/100 g of total fatty acids. Antioxidant properties of roastedapricot (Prunus armeniaca L.) kernels were described by Durmaz andAlpaslan (2007). Apricot kernels are generally exported to European countriesand importer countries use them especially in medicine, cosmetic and oilproduction (Dikilitas 1997; Gezer et al. 2002). Durmaz and Alpaslan (2007)mentioned that apricot kernels are added to bakery products (as whole kernelsor ground) in retail bakeries and also consumed as appetizers. Evaluation ofthe crude apricot kernel oil added to selected types of biscuits and cakesrevealed that it was comparable with corn oil at the equivalent concentration.Apricot kernel oil did not have deteriorative effects on their flavor, color ortexture (Abd El-Aal et al. 1986). However, we have not encountered any reportdescribing the uses of apricot kernel flour (AKF) in bakery products. Theproduction of AKF does not require much processing and has the advantage ofincluding other nutrients.

16 I.T. SEKER ET AL.

Fat is one of the principal ingredients that affect cookie texture, contrib-utes pleasing mouthfeel, and positively impacts flavor intensity and percep-tion. Many cookies contain large amounts of fat. On the other hand, in theU.S.A. and Europe, daily fat consumption represents about 40% of totalcaloric intake. Health specialists recommend that it should not exceed 30% ofthe total calories in a diet (Giese 1996). However, fat cannot be easily replacedin complex food systems such as cookies. Thus, several fat replacers are beingused to replace fat in bakery products. Formulation of reduced-fat bakeryproducts to simulate their high-fat counterparts needs the development of atexture and structure similar to the target (Carroll 1990). Fat could be partiallysubstituted by compounds that present functional properties similar to fat,whereas creation of a high quality fat-free product seems impossible (Shulka1995).

Inglett et al. (1994) concluded that replacement of 50% of fat by solubleb-glucan and amylodextrins derived from oat flour resulted in cookies notsignificantly different from full-fat ones, but at higher substitution levelsoverall quality was decreased. According to the Campbell et al. (1994), sub-stitution for fat exhibites a greater impact on textural attributes of cookies thansubstituton of sugar or flour. Zoulias et al. (2002a) studied the effect of fatreplacement by polydextrose solution in cookies and concluded that replace-ment of up to 35% of fat resulted in cookies with acceptable textural andsensory properties, albeit harder than full-fat cookies.

Reducing fat in everyday diet is a public health issue and a concern formost consumers. Thus, high-fiber and low-fat foods are important objectives intoday’s food product development. As a by-product, apricot kernel offers anexciting new potential as a food ingredient especially in cereal products.

To the authors’ knowledge, there is no published research study investi-gating the possible use of AKF in cookie production. Thus, the objective of thispaper was to study some properties of apricot kernel and to determine theeffect of AKF on the quality of wire-cut cookies and assess the posibility ofusing AKF to partially replace shortening in cookies.

MATERIALS AND METHODS

Materials

The commercial soft wheat flour (Örnek Flour Inc., Nevsehir, Turkey)used in this study consisted of 9.8% protein, 0.65% ash, 28% wet gluten and1.6% total dietary fiber (TDF). Only reagent-grade chemicals were used.Apricot kernels (cv: Hacihaliloglu) were obtained from Malatya provinceduring the summer season of 2003.

17APRICOT KERNEL FLOUR AS FAT REPLACER

Preparation of AKF

Apricot (Prunus armenica L.) pits were obtained from nonsulphitedapricot fruits. The pit consists of kernel and its encasing shell. The kernel is theedible part inside the pit and has a texture similar to almonds. The apricot pitswere washed with tap water and air-dried at 30C for about 2 weeks. Thekernels were obtained by manual cracking and stored at -10C in sealed plasticbags. After soaking the apricot kernels in warm distilled water for 1 h, kernelcoats were removed manually. Then the apricot kernels were placed on a sheetof filter paper and dried on the bench for 2 h and ground in a coffee grinder(Arzum, Istanbul, Turkey) for 1 min. The apricot kernels were again ground ina mortar and pestle and the ground apricot kernels were identified as AKF andused in the proximate analysis and cookie production. To prevent the AKFfrom possible rancidity and oxidation that may occur during storage, the AKFwas prepared fresh within 1 h before the cookie production.

Analytical Methods

Moisture, protein (N ¥ 5.7), ash and wet gluten contents of the soft wheatflour were determined by using American Association of Cereal ChemistsApproved Methods (AACC 2000). Apricot kernel was analyzed for moisture,protein (N ¥ 6.25), ash and lipid contents (AOAC 1998). TDF contents of softwheat flour, apricot kernel and theAKF supplemented cookies were determinedby using AACC Method (AACC 2000). Duplicate dried and milled cookieswere defatted by using petroleum ether (boiling range of 40–60C) and sequen-tial enzymatic digestion was applied by using heat stable a-amylase, proteaseand amyloglucosidase to remove starch and protein. To determine TDF theenzyme digestate was treated with alcohol to precipitate soluble dietary fiberbefore filtering, and TDF residue was washed with alcohol and acetone, driedand weighed. TDF residue values were corrected for protein, ash and blank. Thetests were performed at least in duplicate and mean values reported.

Cookie Preparation and Evaluation

The cookie qualities of AKF supplemented flours were determined byAACC Method No. 10.54 (Baking Quality of Cookie Flour – Micro Wire-CutFormulation) (AACC 2000). AKF was used to partially replace shortening inthe formulation of wire-cut cookies at the concentrations of 10, 20, 30 and40% (w/w, based on the shortening used). A control sample including no AKFwas also prepared. The formulation of the cookies is presented in Table 1. Fourcookies were prepared per bake. The quality parameters of the AKF supple-mented cookies were evaluated in terms of width (W), thickness (T) andspread ratio (W/T), color and texture (maximum force to break the cookie, N)

18 I.T. SEKER ET AL.

values. After cooling of the cookies for 30 min, width and thickness of thecookies were measured using a caliper.

Atexture analyzer (TAPlus, Lloyd Instruments, Hampshire, UK) equippedwith a 3-point bending jig was used for texture analysis and the maximum force(N) required to break the cookies were determined 24 h after baking. The spanbetween the supports was 40 mm. A load cell of 1,000 N was used.

CIE color values (L*, a* and b*) were determined with a Minolta spectro-photometer CM-3600d (Osaka, Japan). The L* value indicates the lightness,0–100 representing dark to light. The a* value gives the degree of the red–greencolor, with a higher positive a* value indicating more red. The b* value indicatesthe degree of the yellow–blue color, with a higher positive b* value indicatingmore yellow. The instrument was standardized against a white tile before use.

The sensory characteristics of the cookies were screened by a six-memberpanel that was well aware of the purpose of the investigation. The panelmembers individually evaluated appearance and taste of the cookies by givingscores ranging between 1 and 5, 5 being the most desirable. Then, the overallsensory scores were calculated as the mean of the appearance and taste scoresfor each bake (Koksel and Özboy 1999). The baked AKF supplementedcookies were cooled (120 min), wrapped and held at room temperature, untilprepared for TDF analysis.

Statistical Evaluation

Data were analyzed for variance using the MSTAT statistical package(Anon 1988). When significant differences were found (P � 0.01), the LSD(Least Significant Difference) test was used to determine the differencesamong means.

TABLE 1.FORMULATION OF COOKIES

Ingredients* Weight (g)

Sucrose (fine granulating) 25.6Brownulated granulated sucrose 8.0Nonfat dry milk 0.8Salt 1.0Sodium bicarbonate 0.8All-purpose shortening (fat) 32.0High-fructose corn syrup 1.2Ammonium bicarbonate 0.4Deionized water VariableFlour† 80.0

* Ingredients at 21 � 1C.† 13% moisture basis.

19APRICOT KERNEL FLOUR AS FAT REPLACER

RESULTS AND DISCUSSION

Properties of AKF

The moisture, protein, ash, lipid and TDF contents of apricot kernels arepresented in Table 2. The composition of apricot kernel generally continuedpreviously published data (Gabrial et al. 1981; Lazos 1991; Aydemir et al.1993; Femenia et al. 1995; Özcan 2000; Özkal et al. 2005; Alpaslan and Hayta2006). Slight differences in the composition may be because of the cultivar ofapricot used and the production area of that apricot. The moisture content ofapricot kernels obtained in this study was 4.2% (Table 2), equivalent to themoisture content reported by Aydemir et al. (1993) and slightly greater thanthe moisture content reported by Özkal et al. (2005).

The protein and fat contents of the apricot kernels were 21.8% and40.2%, respectively (Table 2). The protein content of the apricot kernelreported in this study generally continued the previously published data(Gabrial et al. 1981; Joshi et al. 1986; Lazos 1991; Aydemir et al. 1993;Femenia et al. 1995; Özcan 2000). However, the protein content determined inthis study was smaller than the protein content reported by Abd El-Aal et al.(1986) and El-Adawy et al. (1994), and larger than the protein contentreported by Asma (2000).

The fat content of the apricot kernel continued previously published data(Joshi et al. 1986; Kamel and Kakuda 1992). However, the fat contentobtained in this study was smaller than fat contents reported by Femenia et al.(1995), Asma (2000), Özkal et al. (2005) and larger than the fat contentreported by Lazos (1991).

In this study, ash content of the apricot kernel was 2.71%, slightly largerthan the ash contents determined by Gabrial et al. (1981), Joshi et al. (1986)and Femenia et al. (1995), and almost equal to the ash content reported byÖzcan (2000). The TDF content of apricot kernel used in this study was 35.8%(Table 2).

TABLE 2.PROPERTIES OF APRICOT KERNELS

Percentage (%)*

Moisture 4.2Protein (N ¥ 6.25) 21.8Ash (d.b.) 2.71Fat 40.2Total dietary fiber 35.8

* All analyses are done at least in duplicate.d.b., dry basis.

20 I.T. SEKER ET AL.

AKF and the Quality and Dietary Fiber Content of Cookies

To investigate the effects of the AKF addition on cookie quality, short-ening content in a wire-cut cookie formulation was reduced to 10–40% andreplaced with the equal amounts of the AKF, and the properties of the resultingcookies reported. Width, thickness and spread ratio values, color values,textural and sensory properties and TDF content of the AKF supplementedcookies were evaluated and the results are presented in Tables 3, 4 and 5.

Spread ratio (W/T) is one of the most important properties in evaluatingthe quality of cookies. Greater spread ratios are desirable and indicate a bettercookie quality. Spread ratios of AKF supplemented cookies are presented inTable 3. A slight insignificant increase in the spread ratios was observed at the10% replacement level, but significant decreases were observed in the spreadratios of the cookies with greater than 20% shortening replacement with AKF(P � 0.01).

TABLE 3.APRICOT KERNEL FLOUR (AKF) AND WIDTH, THICKNESS AND SPREAD

RATIO (W/T) OF THE COOKIES*

AKF addition (%) Width (cm) Thickness (cm) Spread ratio

0 7.60 1.02 7.10ab10 7.59 1.04 7.28a20 7.47 1.12 6.69bc30 7.28 1.15 6.31cd40 7.23 1.21 5.98dLSD (P < 0.01) 0.48

* Means followed by the same letter are not significantly different using the least significant differencetest.

TABLE 4.APRICOT KERNEL FLOUR (AKF) AND THE HARDNESS VALUE, OVERALL SENSORY

SCORES AND TOTAL DIETARY FIBER CONTENTS OF THE COOKIES*

AKF addition (%) Hardness (N) Overall sensory score Total dietary fiber (%)

0 47.12 e 3.82 1.86 a10 53.01 d 3.82 3.24 b20 60.10 c 3.82 7.52 c30 71.10 b 3.55 9.12 d40 109.93 a 3.37 12.86 eLSD (P < 0.01) 4.96 ns 0.12

* Means followed by the same letter are not significantly different using the least significant differencetest.

ns, not significant.

21APRICOT KERNEL FLOUR AS FAT REPLACER

Increasing wheat bran addition reduced the spread ratios of high-fiberbran cookies (Özboy and Koksel 1997). Similar results were also obtained incookies supplemented with brewer’s spent grain and sugar beet fiber (Kokseland Özboy 1999; Özturk et al. 2002). Sanchez et al. (1995) also reported thatthe replacement of 35% of fat with carbohydrate-based fat substitutes andemulsifiers exhibited the least negative effects on the physical properties ofcookies, compared with replacement by 45 or 55%.

Since texture is an important factor in the consumer acceptance ofcookies, textural measurements were also conducted to study the effect of fatreduction at selected supplementation levels. The hardness value, related tothe force necessary to break the cookie increased significantly with increas-ing AKF (P � 0.01). Zoulias et al. (2002b) reported that hardness andbrittleness of the cookies generally increased with fat mimetics such as poly-dextrose or maltodextrin, and the results are in aggrement with the presentstudy. Replacement of fat affects the textural characteristics of cookies andbiscuits, and partial replacement suggested (Campbell et al. 1994; Inglettet al. 1994).

Sensory evaluation of cookies in which selected levels of shortening wasreplaced by AKF are presented in Table 4. As the addition level increased,overall sensory scores of these cookies supplemented with AKF were notsignificantly different from sensory scores of the control and they were allacceptable. Drewnowski et al. (1998) reported that the perception of fat incookies was not very accurate and acceptability ratings of sensory panels arerelatively unaffected by a 25% reduction of fat. Zoulias et al. (2002a) reportedthat the organoleptic limit for the fat replacement in cookie formulation was50% because of the decreasing of the overall quality. Although an increase in

TABLE 5.APRICOT KERNEL FLOUR (AKF) AND THE COLOR OF COOKIES*

AKF addition (%) Color values†

L* a* b*

0 70.39 8.35 36.5610 68.37 10.09 37.1020 68.51 10.29 37.0930 69.76 9.47 36.1540 71.84 8.05 34.77LSD (P < 0.01) ns ns ns

* Means followed by the same letter are not significantly different using theLSD test.

† L*, lightness; a*, redness; b*, yellowness.LSD, least significant difference; ns, not significant

22 I.T. SEKER ET AL.

the concentration of AKF resulted in an increase in cookie hardness, hardnessincrease did not affect the overall sensory scores of the cookies. Similar resultswere reported by Zoulias et al. (2000).

TDF content of the cookies supplemented with AKF increased signifi-cantly (P � 0.01) as the AKF concentration increased (Table 4). In the presentresearch, the effect of incorporation of AKF into cookie formulations wasinvestigated for the first time to determine TDF content of the cookies.

The color of the cookies is a characteristic firstly perceived by the con-sumer, and affects the acceptability of the product. Table 5 presents the L*, a*and b* values, which indicate the lightness, redness and yellowness of thecookies, respectively. The color values (L*, a*, b*) did not show significantdifferences as the concentration increased, indicating that AKF addition didnot result in undesirable changes in color of AKF supplemented cookies(Table 5). Similar results were also obtained by Koksel and Özboy (1999) forL* values.

CONCLUSIONS

The purpose of this study was to partially replace shortening in theformulation of wire-cut cookies with AKF at concentrations of 10, 20, 30 and40%. AKF used in this study had relatively high levels of protein, dietary fiberand fat. Although spread ratios and hardness of AKF supplemented cookieswere altered negatively, sensory evaluation revealed that the cookies supple-mented with AKF at all concentrations were acceptable to the panelists.In addition, TDF contents of the cookies supplemented with AKF increasedsignificantly as the concentration increased, which is a very important contri-bution of the apricot kernels to cookies in terms of health benefits. AKFprovided great potential in terms of dietary fiber, fat and protein content. AKFcan used to replace 20% of shortening in cookies without adversely affectingthe spread ratio and 30 and 40% levels without adversely affecting the overallsensory quality.

ACKNOWLEDGMENTS

The authors wish to thank Inonu University Scientific Research Centerfor financial support (Project No.: 2002/10). The authors would also like tothank Örnek Flour Inc. (Nevsehir, Turkey) for providing soft wheat flour,Aytac Biscuit Co. (Kayseri, Turkey) for providing fine granulating sucrose,brownulated granulated sugar and all-purpose shortening, and Ulker Co.(Ankara, Turkey) for providing high-fructose corn syrup.

23APRICOT KERNEL FLOUR AS FAT REPLACER

REFERENCES

AACC. 2000. American Association of Cereal Chemists, Approved Methods ofthe AACC, 10th Ed., The Association, St. Paul, MN.

ABD EL-AAL, M.H., KHALIL, M.K.M. and RAHMA, E.H. 1986. Apricotkernel oil: Characterization, chemical composition and utilization insome baked products. Food Chem. 19, 287–298.

ALPASLAN, M. and HAYTA, M. 2006. Apricot kernel: Physical andchemical properties. J. Am. Oil Chem. Soc. 83, 469–471.

ANONYMOUS. 1988. User’s Guide to MSTAT-C. A Software Program for theDesign, Management and Analysis of Agronomic Research Experiments.Michigan State University, East Lansing, MI.

AOAC. 1998. Official Methods of Analysis of the Association of OfficialAnalytical Chemists. Association of Official Chemists, Inc., Arlington,VA.

ASMA, B.M. 2000. Apricot Growing. Evin Publishers, Malatya, Turkey.AYDEMIR, T., YILMAZ, I., OZDEMIR, I. and ARIKAN, N. 1993. Kayisi

çekirdegi yaginin fiziksel ve kimyasal özelliklerinin incelenmesi. DogaTürk Kimya Dergisi 17, 56–61.

CARROLL, L.E. 1990. Stabilizer systems reduce texture problems inmulticomponent foods and bakery products. Food Technol. 44, 94–98.

CAMPBELL, L.A., KETELSEN, S.M. and ANTENUCCI, R.N. 1994.Formulating oatmeal cookies with calorie-sparing ingredients. FoodTechnol. 48, 98–105.

DIKILITAS, S. 1997. A Research on Efficiency Analysis and Improvements ofPrototype Apricot Pit Breaking Machine. Harran University ScienceInstitute, Sanliurfa, Turkey.

DREWNOWSKI, A., NORDESTEN, K. and DWYER, J. 1998. Replacingsugar and fat in cookies impact on product quality and preference. FoodQual. Pref. 9, 13–20.

DURMAZ, G. and ALPASLAN, M. 2007. Antioxidant properties of roastedapricot (Prunus armeniaca L.) kernel. Food Chem. 100, 1177–1181.

EL-ADAWY, T.A., RAHMA, A.H., El-BADAWEY, A.A., GOMAA, M.A.,LASZTITY, R. and SARKADI, L. 1994. Biochemical studies of somenon-conventional sources of proteins. Part 7. Effect of detoxificationtreatments on the nutritional quality of apricot kernels. Nahrung 38,12–20.

FAO. 1998. Production Year Book. FAO Publ., Rome, Italy.FEMENIA, A., ROSSELLO, C., MULET, A. and CANELLAS, J. 1995.

Chemical composition of bitter and sweet apricot kernels. J. Agric. FoodChem. 43, 356–361.

24 I.T. SEKER ET AL.

GABRIAL, G.N., EL-NAHRY, F.I., AWADALLA, M.Z. and GIRGIS, S.M.1981. Unconventional protein sources: Apricot seed kernels. Z.Ernahrungswiss 20, 208–215.

GEZER, I., HACISEFEROGULLARI, H. and DEMIR, F. 2002. Some physi-cal properties of Hacihaliloglu apricot pit and its kernel. J. Food Eng. 56,49–57.

GIESE, J. 1996. Fats and fat replacers: Balancing the health benefits. FoodTechnol. 50, 76–78.

INGLETT, G.E., WARNER, K. and NEWMAN, R.K. 1994. Sensoryand nutritional evaluations of oatrim. Cereal Foods World 39, 755–759.

IORDANIDOU, P., VOGLIS, N., LIADAKIS, G.N. and TZIA, C. 1999.Utilization of apricot processing wastes. In ISHS Acta Horticulture, XIInternational Symposium on Apricot Culture, May 25–30, 1999, Veria-Makedonia, Greece.

JOSHI, S., SRIVASTAVA, R.K. and DHAR, D.N. 1986. The chemistry ofPrunus armenica, Br. Food J. 88, 74–78, 80.

KAMEL, B.S. and KAKUDA, Y. 1992. Characterisation of the seed oil andmeal from apricot, cherry, nectarine, peach and plum. J. Am. Oil. Chem.Soc. 69, 493–494.

KOKSEL, H. and ÖZBOY, Ö. 1999. Effects of sugar beet fiber on cookiequality. ZuckerIndustrie 124, 542–544.

LAZOS, E.S. 1991. Composition and oil characteristics of apricot, peach andcherry kernel. Grasas Y Aceites 42, 127–131.

ÖZBOY, Ö. and KOKSEL, H. 1997. Comparison of the effects of two wheatcultivars on the quality of high fiber bran cookies. Gida 22, 9–14.

ÖZCAN, M. 2000. Composition of some apricot (Prunus armenica L.) kernelsgrown in Turkey. Acta Aliment. 29, 289–293.

ÖZKAL, S.G., YENER, M.E. and BAYINDIRLI, L. 2005. Mass transfermodeling of apricot kernel oil extraction with supercritical carbondioxide. J. Supercrit. Fluid 35, 119–127.

ÖZTURK, S., ÖZBOY, Ö., CAVIDOGLU, I. and KÖKSEL, H. 2002. Effectsof brewer’s spent grain on the quality and dietary fiber content of cookies.J. Inst. Brew. 108, 23–27.

SANCHEZ, C., KLOPFENSTEIN, C.F. and WALKER, C.E. 1995. Use ofcarbohydrate-based fat substitutes and emulsifiying agents in reduced fatshortbread cookies. Cereal Chem. 72, 25–29.

SHULKA, T.P. 1995. Problems in fat free and sugarless baking. Cereal FoodsWorld 40, 159–160.

ZOULIAS, E.I., OREOPOULOU, V. and TZIA, C. 2000. Effects of fat mimet-ics on physical, textural and sensory properties of cookies. Int. J. FoodProp. 3, 385–397.

25APRICOT KERNEL FLOUR AS FAT REPLACER

ZOULIAS, E.I., OREOPOULOU, V. and KOUNALAKI, E. 2002a. Effects offat and sugar replacement on cookie properties. J. Sci. Food Agric. 82,1637–1644.

ZOULIAS, E.I., OREOPOULOU, V. and TZIA, C. 2002b. Textural propertiesof low-fat cookies containing carbohydrate- or protein-based fatreplacers. J. Food Eng. 55, 337–342.

26 I.T. SEKER ET AL.