Food Chemistry 187 (2015) 525–529
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Evaluation of canola oil oleogels with candelilla wax as an alternative to shortening in baked goods Areum Jang a, Woosung Bae a, Hong-Sik Hwang b, Hyeon Gyu Lee c, Suyong Lee a,⇑ a
Department of Food Science & Technology and Carbohydrate Bioproduct Research Center, Sejong University, 98 Gunja-dong, Gwangjin-gu, Seoul 143-747, Republic of Korea United States Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Functional Foods Research, Peoria, IL, USA1 c Department of Food and Nutrition, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Republic of Korea b
a r t i c l e
i n f o
Article history: Received 29 January 2015 Received in revised form 22 April 2015 Accepted 23 April 2015 Available online 24 April 2015 Keywords: Oleogel Canola oil Candelilla wax Shortening Cookie
a b s t r a c t The oleogels of canola oil with candelilla wax were prepared and utilized as a shortening replacer to produce cookies with a high level of unsaturated fatty acids. The incorporation of candelilla wax (3% and 6% by weight) to canola oil produced the oleogels with solid-like properties. The ﬁrmness of the oleogels was lower than that of the shortening at room temperature. A more rapid change in the viscosity with temperature was observed with increasing levels of candelilla wax in the steady shear measurements. The replacement of shortening with oleogels in the cookie formulation reduced both viscoelastic parameters (G0 and G00 ) of the cookie doughs. The level of unsaturated fatty acids in the oleogel cookies was distinctly increased up to around 92%, compared to the shortening cookies (47.2%). The cookies with the oleogels showed desirable spreadable property and the replacement of shortening with the oleogels produced cookies with soft eating characteristics. Ó 2015 Elsevier Ltd. All rights reserved.
1. Introduction Shortening is an edible fat that has been traditionally used to make baked products such as pastries, cakes, and cookies. Since shortening prevents the cohesion of gluten strands during mixing (Gervajio & Shahidi, 2005), it plays a critical role in the tender texture and mouthfeel of the ﬁnal products. In addition, shortening imparts other functional characteristics such as aeration and stability, positively contributing to the structure and geometry of the products. However, with the recent well-being trend, a great deal of effort has been made to reduce the use of shortening due to a high level of saturated fatty acids as well as the possible presence of trans fatty acids. In practice, it may be possible to apply vegetable oil to baked goods instead of shortening. However, the use of vegetable oil produces baked goods with more greasy and less crispy characteristics, and also decreases the storage stability of the products mainly due to oil oxidation. In addition, the low viscosity of the oil causes a difﬁculty in handling and shaping dough. There are a number of preceding studies where shortening ⇑ Corresponding author. E-mail address: [email protected]
(S. Lee). Mention of trade names or commercial products in this article is solely for the purpose of providing scientiﬁc information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. USDA is an equal opportunity provider and employer. 1
http://dx.doi.org/10.1016/j.foodchem.2015.04.110 0308-8146/Ó 2015 Elsevier Ltd. All rights reserved.
was replaced with a variety of carbohydrate-, protein-, and lipidbased ingredients (Lim, Inglett, & Lee, 2010). However, carbohydrate- and protein-based fat replacers could be applied only for the partial replacement of shortening. Although lipid-based fat replacers could be used by replacing fat on an equal weight basis, additional chemical or enzymatic operations for the structural modiﬁcation may be necessary to produce the lipid-based fat replacers (Akoh, 1998). Thus, as there have been no ideal ingredients for shortening replacement, shortening replacers are more likely to be customized to meet a speciﬁc application. Recently, a new technique called organogelation has been receiving great attention in order to structure edible oils by the use of gelling agents. Through this organogelation, organic liquid can be entrapped in a thermo-reversible gel network, producing oleogels with solid-like properties. Since these oleogels have speciﬁc consistency and ﬁrmness without changing their chemical compositions, they are shown to have great potential applications in the food, cosmetics, and pharmaceutical industry (Marangoni, 2012). Speciﬁcally, the use of the oleogels imparts such various functionalities to foods as the restricted oil migration, saturated and trans fat replacement, and emulsion stability (Hughes, Marangoni, Wright, Rogers, & Rush, 2009). Nonetheless, the oleogels are still under-utilized in terms of food-related applications. There are only a few preceding studies where the ethylcellulose and rice bran wax oleogels were applied to meat products (Zetzl, 2013; Zetzl, Marangoni, & Barbut, 2012) and ice cream (Zulim
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Botega, Marangoni, Smith, & Goff, 2013), respectively. Hence, there is a need to extend the use of oleogels to a wider variety of food products. Candelilla wax used in this study is regarded as a food additive approved by the US FDA and has been often used as a glazing agent in the food industry (Marangoni & Garti, 2011). Oleogels were previously prepared by using candelilla wax with safﬂower (0.5–6%, w/v) (Toro-Vazquez et al., 2007) and soybean oil (0.5–4%, w/w) (Rocha et al., 2013). In these studies, main research focus was placed on the rheological and thermal properties of the oleogels rather than their processing performance in a food system. Furthermore, canola oil oleogels with candelilla wax have not been prepared to our best knowledge. In this study, the oleogels of canola oil with candelilla wax were prepared and their rheological properties were characterized. They were then incorporated into the formulation of cookies as a shortening replacer and their effects on the physicochemical properties of the cookies were investigated. 2. Materials and methods 2.1. Preparation of oleogels Candelilla wax (Kahl GmbH & Co. KG, Trittau, Germany) was added to canola oil (CJ Co., Seoul, Korea) at two levels (3% and 6% w/w) and the mixtures were heated at 160 °C, followed by continuous agitation using an overhead mechanical stirrer for 10 min. They were then placed at room temperature overnight, producing the oleogel samples. 2.2. Firmness measurement of oleogels A puncture test was applied to investigate the ﬁrmness of oleogels which was compared with that of shortening. Based on the method of Hwang, Singh, Winkler-Moser, Bakota, and Liu (2014), the oleogel samples (14 g) in vials were placed on the platform of a texture analyzer (TMS-Pro, Food Technology Co., Virginia, USA) with a 25 N load cell. A cylindrical probe (0.5 cm diameter) was then lowered 10 mm into the oleogel samples at a crosshead speed of 100 mm/min at room temperature. The maximum force that is a measure of ﬁrmness was recorded from the plot of force versus penetration distance. 2.3. Rheological measurements of oleogels The ﬂow behaviors of shortening and oleogels were measured as a function of temperature by using a controlled-stress rheometer (AR1500ex, TA Instruments, New Castle, DE, USA) with parallel plates (40 mm diameter). For the viscosity measurement, the shortening and oleogels were placed at 50 °C until they were completely melted, and then loaded onto the peltier plate of the rheometer. Their steady shear viscosities at a constant shear rate of 100/s were then monitored by increasing temperature from 50 to 90 °C at a heating rate of 2 °C/min. 2.4. Preparation of cookies with oleogels The cookie samples were prepared according to the AACC-approved method (Method 10–52, AACC (2009)) with modiﬁcations. First, cream was prepared by blending shortening (126 g, Dongsuh Oil & Fats Co., Changwon, Korea) with sugar (252 g, CJ Co., Seoul, Korea), nonfat dry milk (12.6 g, Seoul Dairy Co., Seoul, Korea), and baking powder (4.2 g, JENICO Co., Seoul, Korea) by using a KitchenAid mixer (St Joseph, MI, USA) on speed 2 for 2 min. After scraping down, the mixing was continued on speed 4 for 1 min.
The cream (112.8 g) was mixed with sodium bicarbonate solution (0.95 M, 12 g, Daejung Chemicals & Materials Co., Gyeonggido, Korea), sodium chloride solution (1.52 M, 6 g, Daejung Chemicals & Materials Co., Gyeonggido, Korea), and water (8.1 g) on speed 2 for 3 min. After scraping down, commercial soft wheat cookie ﬂour (CJ Co., Seoul, Korea) was added to the cream mixture and then mixed on speed 2 for 2 min. The cookie dough was rolled to a thickness of 10 mm and cut to a diameter of 6 cm. After baking at 205 °C for 10 min, the cookies were cooled for 60 min on a wire rack and sealed in a plastic bag. For the cookies with oleogels, shortening was replaced with the oleogels on a weight basis. 2.5. Dynamic viscoelastic measurement of cookie dough The dynamic viscoelastic properties (G0 and G00 ) of the cookie dough prepared with shortening and oleogels were measured at 25 °C by using a controlled-stress rheometer (AR 1500ex, TA instruments, New castle, DE, USA). A serrated parallel plate (40mm diameter) was used to prevent slippage. A frequency sweep test was performed as a function of frequency from 0.01 to 10 Hz at the strain of 0.05% which was within the linear viscoelastic regime for all the cookie dough samples. The exposed edge of cookie dough was covered with a thin layer of mineral oil in order to prevent moisture loss during the rheological testing. 2.6. Measurement of fatty acid composition of cookies Fatty acid composition of the cookie samples prepared with the oleogels was determined by using a GC-FID system (7890A, Agilent Technologies, DE, USA) and compared with that of the cookies with shortening. Cookies were ground to pass through a 20 mesh sieve by using a laboratory grinder (HMF-3150S, Hanil electric, Seoul, Korea). The cookie powder (18 g) was placed in a Soxhlet thimble and the lipids were extracted with ethyl ether (200 mL) for 12 h. Each lipid sample was methylated with 14% BF-methanol reagent after hydrolysis with 0.5 mol/L NaOH-methanol solution (Shirasawa, Sasaki, Saida, & Satoh, 2007). The fatty acid methyl esters were injected into a SPTM-2560 capillary column (100 m 0.25 mm ID 0.2 lm thickness, Supelco, Bellefonte, PA, USA). The oven temperature was programmed to be 140 °C for 5 min and raised to 210 °C (4 °C/min) which was held for 10 min, then to 240 °C (5 °C/min) which was held for 5 min, and ﬁnally to 250 °C (4 °C/min) which was held for 5 min. Helium was used as carrier gas and commercial fatty acid standards (37 component FAME Mix) were obtained from Supelco (Bellefonte, PA, USA). The fatty acid compositions were expressed as the area percentage of the total peak area from all methyl esters. 2.7. Measurement of cookie geometry According to the AACC approved method (10–52, AACC (2009)), the average width of a cookie was measured by placing six cookies edge-to-edge which were rotated 90° four times. The cookie thickness was also measured by stacking six cookies which were re-stacked twice. The spread factor was obtained from the ratio of cookie width to height. 2.8. Textural measurement of cookies The breaking force of cookies was measured by using a threepoint bending test. The cookies were supported by two separate beams and fractured by lowering a metal probe (0.3 cm thick and 9 cm wide) at a crosshead speed of 60 mm/min. The maximum peak force was measured as the snapping force of the cookie samples.
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2.9. Statistical analysis All experiments were performed in triplicate and the results were statistically analyzed with SAS software (SAS Institute, Cary, NC, USA). Duncan’s multiple range tests were performed to determine any signiﬁcant difference among the samples at a conﬁdence level of 95%. 3. Results and discussion Fig. 1(a) exhibits the visual appearance of the oleogels prepared from canola oil with candelilla wax. As clearly illustrated in Fig. 1(a), the canola oil in a liquid form was transformed into the translucent and ﬁrm oleogels at the two levels (3% and 6%) of candelilla wax. Thus, the physical properties of the liquid oil were readily modiﬁed by the addition of candelilla wax without chemical modiﬁcations. The mechanical properties of the canola oil oleogels were then investigated by measuring the oleogel ﬁrmness that is deﬁned as the force required to generate a given deformation. As shown in Fig. 1(b), the shortening had higher values of ﬁrmness than the oleogel samples. The oleogels had a tendency to be ﬁrmer with increasing levels of candelilla wax. The ﬂow behaviors of the oleogels prepared with canola oil and candelilla wax were measured as a function of temperature. As shown in Fig. 2, the viscosity of all the samples had a tendency to decrease in a non-linear way with increasing temperature. It is interesting to note that the oleogels clearly exhibited higher values of viscosity than the shortening at the temperatures between 50 and 70 °C. Thus, the viscosity of the oleogels was dependent on the percentage of candelilla wax used. In addition, the viscosity curves were ﬁtted into the Arrhenius equation for evaluating the effect of temperature on the ﬂow behaviors of the oleogels.
Fig. 1. Visual appearance (a) and ﬁrmness (b) of the oleogels of canola oil with candelilla wax (3% and 6%, w/w).
g ¼ A EXPðEa =RTÞ where g is the oil viscosity (Pas), A is the pre-exponential factor (Pas), Ea is the activation energy (J/mol), R is the gas constant (J/mol K), and T is the absolute temperature (K). The viscosity of the oleogels over temperature was well-characterized by the Arrhenius equation (R2 > 0.9598). The activation energy (Ea) of each sample was obtained from the slope of the plot of ln (viscosity) versus 1/T. It is recognized that Ea is a measure of the sensitivity of a material to temperature change (Steffe, 1996). As presented in Table 1, the Ea values of the shortening, 3% oleogel, and 6% oleogel were determined to be 1.73E+07, 2.39E+07, and 4.06E+07 J/mol, respectively. The oleogels exhibited higher values of Ea than the shortening, and the Ea values also appeared to increase with increasing levels of candelilla wax. These results indicated that the viscosity of the oleogels containing more candelilla wax was highly dependent on the temperature change. Table 1 also presents the viscosity values of the shortening and two oleogels at 205 °C (cookie baking temperature) which were estimated from each Arrhenius equation. As can be easily expected from the Ea values, the 6% oleogel sample had the lowest value of viscosity at 205 °C while the highest value of viscosity was shown in the shortening. Therefore, these viscosity differences among the samples may affect the baking performance of cookies which was mentioned in the later section of this study. The dynamic viscoelastic properties of the cookie dough samples prepared with shortening and oleogels were evaluated as a function of frequency (Fig. 3). The storage (G0 ) and loss (G00 ) moduli had a tendency to increase with increasing frequency, showing frequency dependence. Also, all the samples exhibited higher values of G0 than those of G00 , showing more elastic characteristics. It is interesting to note that the cookie dough prepared with shortening showed higher values of G0 and G00 , compared to the
Fig. 2. Effect of temperature on the ﬂow behaviors of shortening and oleogels.
oleogel-incorporated samples. These rheological properties could be attributed to the ﬁrmer texture of shortening as already mentioned in Fig. 1(b). The fatty acid compositions of the cookies prepared with oleogels were analyzed and compared with that of the control cookie prepared with shortening. It is recognized that canola oil is high in healthier unsaturated fats, compared to other vegetable oils (Kim, Kim, Lee, Yoo, & Lee, 2010). Therefore, canola oil was chosen in this study to prepare oleogel samples containing a high level of unsaturated fatty acid. As can be seen Table 2, the predominant component of the shortening-incorporated cookies was palmitic acid (16:0, 41.9%) while the oleogel cookie samples were rich in oleic (18:1, 62%), linoleic (18:2, 20%), and linolenic (18:3, 7%) acids. These fatty acid proﬁles were in agreement with that of the canola oil reported by Gervajio and Shahidi (2005). This result indicated that the baking process did not change the fatty acid composition. The percent amount of total saturated and unsaturated fatty acids in the shortening was determined to be 52.8% and 47.2%, respectively. In the case of the oleogel-incorporated cookies, the level of unsaturated fatty acids was distinctly increased up to around 90–92% and the level of saturated fatty
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Table 1 Arrhenius model parameters of shortening and oleogels and their predicted viscosity at 205 °C (means with different letters in the same row differ signiﬁcantly at p < 0.05).
Ea (J/mol) A (Pas) Viscosity (Pas, 205 °C)
1.73E+07 ± 2.98E+05c 4.50E05 ± 4.40E06a 3.52E03 ± 7.45E05a
2.39E+07 ± 2.66E+05b 5.04E06 ± 4.62E07b 2.04E03 ± 4.80E05b
4.06E+07 ± 8.13E+05a 1.77E08 ± 4.60E09b 4.80E04 ± 2.92E05c
Table 3 Geometry and texture of cookies prepared with shortening and oleogels (means with different letters in the same row differ signiﬁcantly at p < 0.05).
Diameter (cm) Height (cm) Spread factor Snapping force (N)
Fig. 3. Dynamic viscoelastic properties of cookie dough prepared with shortening and oleogels.
acids was reduced to 8–10%. Thus, the use of oleogel for shortening produced the cookies containing a high level of unsaturated fatty acids. The extensible ﬁlm formation of soft wheat ﬂour rather than an elastic network results in the structural features of the cookies including macroscopic collapse, giving rise to the lateral expansion (Lee, Warner, & Inglett, 2005). Therefore, the spread factor has been used as a measure of cookie quality attributes (Doescher, Hoseney, Milliken, & Rubenthaler, 1987). The dimensions of the cookie samples were measured in order to investigate the effect of oleogels on the spreading characteristics of cookies. As shown in Table 3, the diameter and height of the cookies prepared with shortening were 8.38 and 1.30 cm, respectively. In the case of the 6% oleogel cookies, the corresponding values were determined to be 9.12 and 1.16 cm, respectively. Therefore, the results showed
Table 2 Fatty acid compositions of canola oil and cookies prepared with shortening and oleogels. (%)
C12:0 C14:0 C16:0 C16:1 C18:0 C18:1 C18:2 C18:3 C20:0 C20:1 C22:0 C23:0 C24:0
– 0.1 ± 0.0 4.5 ± 0.0 0.2 ± 0.0 1.6 ± 0.1 64.0 ± 1.1 20.0 ± 0.2 6.9 ± 0.9 0.6 ± 0.0 1.7 ± 0.1 0.3 ± 0.0 – 0.2 ± 0.0
3.3 ± 0.0 2.2 ± 0.0 41.9 ± 0.0 0.1 ± 0.0 5.0 ± 0.0 32.7 ± 0.0 13.3 ± 0.0 0.8 ± 0.0 0.4 ± 0.0 0.2 ± 0.0 0.1 ± 0.0 – 0.1 ± 0.0
– 0.1 ± 0.0 4.4 ± 0.2 0.2 ± 0.0 1.9 ± 0.2 61.9 ± 1.4 20.0 ± 0.3 7.7 ± 1.3 0.6 ± 0.0 1.8 ± 0.1 0.3 ± 0.0 1.0 ± 0.0 0.2 ± 0.0
– 0.1 ± 0.0 4.5 ± 0.2 0.2 ± 0.0 2.0 ± 0.0 62.6 ± 0.1 19.3 ± 0.1 6.0 ± 0.0 0.6 ± 0.0 1.6 ± 0.0 0.4 ± 0.0 2.3 ± 0.2 0.2 ± 0.0
7.2 ± 0.1 92.8 ± 0.1
52.8 ± 0.1 47.2 ± 0.1
8.5 ± 0.3 91.5 ± 0.3
10.2 ± 0.1 89.8 ± 0.1
8.38 ± 0.02c 1.30 ± 0.00a 6.45 ± 0.02c 71.67 ± 10.11a
8.97 ± 0.03b 1.20 ± 0.01b 7.49 ± 0.06b 63.74 ± 8.83b
9.12 ± 0.02a 1.16 ± 0.01c 7.87 ± 0.05a 53.42 ± 7.08c
the increased diameter and decreased height of the cookie samples prepared with the oleogels, implying desirable spreadable characteristics. This result could be attributed to the low viscosity of the oleogels at the baking temperature (Table 1) which could play a positive role in the expansion and collapse of the cookies during baking. Although there are several preceding studies on the reduction of shortening in the cookies, the spread factor showed a decline with decreasing amount of shortening (Lee et al., 2005; Zoulias, Oreopoulou, & Kounalaki, 2002). Thus, one of the critical challenges to replace shortening in the cookies has been to overcome the loss of the spreadability. In this study, the replacement of shortening with the canola oil oleogels positively contributed to the physical quality attributes of the cookies. Snapping which is to suddenly break under an applied force is one of the important physical attributes of cookies. Therefore, the effect of oleogels on the snapping property of cookies was investigated by using a three point bending test. Table 3 presents the snapping force required to fracture the cookies in half. The snapping force of the control cookies prepared with shortening was determined to be 71.67 N while that of the 6% oleogel-incorporated cookies was 53.42 N. Thus, greater force was needed to fracture the control cookies with shortening whereas the oleogel-incorporated cookies had lower values of snapping force. It seemed that these reduced snapping property contributed to the softer eating characteristics of the cookies prepared with the oleogels (Lin, Lee, Mau, Lin, & Chiou, 2010). 4. Conclusions Canola oil was structured with candelilla wax to produce oleogels with solid-like properties and the oleogels were utilized as an alternative to shortening in cookies. The use of the oleogels for shortening produced cookie samples rich in unsaturated fatty acids and low in saturated fatty acids. In addition, the low viscosity of the oleogels at the baking temperature imparted desirable spreadable characteristics to the cookies. Thereby, the extensive use of oleogels will contribute to the reduction of saturated fatty acids and elimination of trans-fatty acids from the diet, consequently providing beneﬁcial health effects. In a further study, sensory evaluation will be necessary to investigate consumer preferences for the oleogel-incorporated baked goods. Acknowledgement This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2013R1A1A2A10004640).
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References AACC (2009). Approved methods of the American Association of Cereal Chemists. Method, 10.02–52.02. St. Paul. MN, USA: American Association of Cereal Chemists. Akoh, C. C. (1998). Fat replacers. Food Technology, 52(3), 47–53. Doescher, L. C., Hoseney, R., Milliken, G., & Rubenthaler, G. (1987). Effect of sugars and ﬂours on cookie spread evaluated by time-lapse photography. Cereal Chemistry, 64(3), 163–167. Gervajio, G., & Shahidi, F. (2005). Bailey’s industrial oil and fat products. New York: John Willey & Sons Inc. Hughes, N. E., Marangoni, A. G., Wright, A. J., Rogers, M. A., & Rush, J. W. (2009). Potential food applications of edible oil organogels. Trends in Food Science & Technology, 20(10), 470–480. Hwang, H. S., Singh, M., Winkler-Moser, J. K., Bakota, E. L., & Liu, S. X. (2014). Preparation of margarines from organogels of sunﬂower wax and vegetable oils. Journal of Food Science, 79(10), C1926–C1932. Kim, J., Kim, D. N., Lee, S. H., Yoo, S.-H., & Lee, S. (2010). Correlation of fatty acid composition of vegetable oils with rheological behaviour and oil uptake. Food Chemistry, 118(2), 398–402. Lee, S., Warner, K., & Inglett, G. E. (2005). Rheological properties and baking performance of new oat b-glucan-rich hydrocolloids. Journal of Agricultural and Food Chemistry, 53(25), 9805–9809. Lim, J., Inglett, G. E., & Lee, S. (2010). Response to consumer demand for reduced-Fat foods; multi-functional fat replacers. Japan Journal of Food Engineering, 11(4), 147–152. Lin, S. D., Lee, C. C., Mau, J. L., Lin, L. Y., & Chiou, S. Y. (2010). Effect of erythritol on quality characteristics of reduced-calorie Danish cookies. Journal of Food Quality, 33(s1), 14–26.
Marangoni, A. G. (2012). Organogels: an alternative edible oil-structuring method. Journal of the American Oil Chemists’ Society, 89(5), 749–780. Marangoni, A. G., & Garti, N. (2011). Edible Oleogels: Structure and Health Implications. Urbana, IL: AOCS Press. Rocha, J. C. B., Lopes, J. D., Mascarenhas, M. C. N., Arellano, D. B., Guerreiro, L. M. R., & da Cunha, R. L. (2013). Thermal and rheological properties of organogels formed by sugarcane or candelilla wax in soybean oil. Food Research International, 50(1), 318–323. Shirasawa, S., Sasaki, A., Saida, Y., & Satoh, C. (2007). A rapid method for trans-fatty acid determination using a single capillary GC. Journal of Oleo Science, 56(2), 53–58. Steffe, J. F. (1996). Rheological methods in food process engineering. East lansing: Freeman press. Toro-Vazquez, J., Morales-Rueda, J., Dibildox-Alvarado, E., Charo-Alonso, M., AlonzoMacias, M., & González-Chávez, M. (2007). Thermal and textural properties of organogels developed by candelilla wax in safﬂower oil. Journal of the American Oil Chemists’ Society, 84(11), 989–1000. Zetzl, A. K. (2013). Microstructure and mechanical properties of ethylcellulose oleogels and their fat substitution potential in the meat industry. MS thesis, Ontario, Canada. Zetzl, A. K., Marangoni, A. G., & Barbut, S. (2012). Mechanical properties of ethylcellulose oleogels and their potential for saturated fat reduction in frankfurters. Food and Function, 3(3), 327–337. Zoulias, E. I., Oreopoulou, V., & Kounalaki, E. (2002). Effect of fat and sugar replacement on cookie properties. Journal of the Science of Food and Agriculture, 82(14), 1637–1644. Zulim Botega, D. C., Marangoni, A. G., Smith, A. K., & Goff, H. D. (2013). The potential application of rice bran wax oleogel to replace solid fat and enhance unsaturated fat content in ice cream. Journal of Food Science, 78(9), C1334–C1339.