Brittany Huschka*^a, Carolyn Challacombe^a, Jens Dreisoerner ^b, Koushik Seetharaman^a

^aDepartment of Food Science, University of Guelph, Guelph, Ontario, Canada

^bBrabender GmbH & Co. Duisburg, Germany

Abstract

The development of a monoacylglycerol-stabilized oil in water emulsion (MAG gel) is a recent advance in the development of alternate shortening that is free of trans fats.  However, the behaviour of MAG gels in dough systems has not been investigated.  In this study we investigated the effect of MAG gel at different levels (6-24%) in dough to dough with oil, interesterified shortening (IE) or a mixture of oil and monoacylglycerol in the same proportions as in the gel. Dough was prepared with different lipid types using hard or soft wheat flours at equivalent fat contents.  Mixing and water absorption parameters to 500 BU were evaluated by using a Farinograph. Dough firmness, stickiness and extensibility were measured by using the texture analyzer, and gluten behavior was measured by using a Gluten Peak Tester (GPT).  Water absorption values had a general decreasing trend as lipid content increased. Differences were observed in mixing behaviors in the Farinogram and the trends were similar when different lipids were used.  Oil, mixture and MAG gel exhibited a delayed trend, while IE showed an opposite trend, with a quick development and increased breakdown.  The MAG gel exhibited unique differences in dough rheology parameters, behaving similar to IE for stickiness, and similar to the mixture for extensibility and resistance to extension parameters.  However the trends were not similar when used with hard or soft wheat dough.  Depending on the type of lipid used, the maximum torque and onset of development of torque was different for the different treatments in the GPT.  The trends were different between different types of lipids and whether they were used with hard or soft wheat flours. These results suggest that further evaluations are necessary to effectively use MAG gels in baked product systems. Furthermore, the GPT provided another dimension of information that was not elucidated by the traditional Farinograph or dough rheology techniques.

Introduction

A novel, structured oil was recently developed at the University of Guelph, to be utilized as a shortening alternative that is trans fat free and low in saturated fats.  This material is a cellular-solid structure as an oil-in-water emulsion with water-swollen MAG multilamellae surrounding 1-5 micrometer oil globules.  The globules are in contact with each other via hydrogen bonding.  Questions remain on the MAG gels use and functionality in baked products, including how the structure of the MAG gel interacts with the dough matrix compared to the individual structural components and how the water in the structured MAG gel influences dough processing.  These experiments attempt to compare the effects of the MAG gel on hard and soft wheat dough properties including farinogram mixing behaviour, stickiness, resistance to extension and gluten peak tester profiles compared to the unstructured components of the gel and other traditional lipid sources utilized for baked goods.

Materials and Methods

The experiments were run with hard wheat flour (HWF)(12 ±0.5% moisture, 12 ± 0.14% protein) or soft wheat flour  (SWF)(12 ±0.6% moisture, 8 ± 0.03% protein).  The MAG gel composition is 55.2% canola oil, 40% water, 4.5% distilled monoglyceride (Danisco, HSKA) and 0.3% stearic acid.  The MAG gel was produced by vigorously mixing a hot oil-monoglyceride solution with alkaline deionized water.  The additional lipids used included an unstructured mixture of the components of the MAG gel (canola oil, 7.5% distilled monoglyceride), oil and an interesterified soy shortening (ADM).  The fats were added to flour on a lipid weight basis at 6, 12, 18, or 24% for the farinograph and dough rheology experiments, and at 6 or 12% for the Gluten Peak Tester.

Photograph of MAG gel

Farinograph

Hard and soft wheat flour samples with lipid levels at 0, 6, 12, 18 or 24% were analyzed in the Farinograph-E (AACC Method 54-21A), with the 50g mixing bowl.  Water absorption values were adjusted to obtain a consistency of 500 BU.

Texture Analysis

Textural characteristics of the dough were measured using a TA-XTPlus Texture Analyser (Scarsdale, New York, USA).  Doughs were prepared in the Farinograph-E using the method as previously stated, but were removed from the Farinograph-E 30 seconds after peak.  The dough was then used for stickiness and extensibility tests.  Dough stickiness was determined using the SMS/Chen-Hoseney Dough Stickiness Rig (A/DSC), and the method described by Chen and Hoseney, 1995.  Resistance to extension was determined using Kieffer Dough & Gluten Extensibility Rig (A/KIE) according to the method described by Smewing, 1995.

Gluten Peak Tester

Hard wheat flour, and soft wheat flour with the addition of 6 or 12% lipid levels were analyzed with in a Gluten Peak Tester (GPT).  Hard wheat flour samples were evaluated at a ratio of 0.85 (flour: water) and soft wheat flour samples were evaluated at a ratio of 1.19 (flour: water).  The samples were mixed in a cup at 3000 rpm and the lift off time, peak time and peak torques was recorded.

Results

Figure 2: Farinogram curves of HWF and 6 or 24% MAG gel or mixture. MAG gel and mixture show delayed development at the 24% lipid addition level. The arrows indicate 30 seconds after peak where samples were taken for rheology testing

Figure 3: Farinogram curves of SWF and 6 or 24% MAG gel or mixture. MAG gel and mixture show delayed development at the 24% lipid addition level. The MAG gel’s slope to development is more exaggerated and occurs 5.6 minutes earlier then the mixture.

Figure 4: Water absorption to reach the 500 BU line on the Farinograph-E. Solid red line represents compensated water absorption if the water structuring the MAG gel is included in the water absorption value. The trend and amount of change was different for HWF and SWF with the MAG gel or mixture because of the functionality of their water and lipid components and the interactions with gluten and starch.

Figure 5: Stickiness values determined by Texture Analysis for HWF or SWF and 0, 6, 12, 18 or 24% lipid addition. Stickiness is lower then control in both flours with a larger decrease in SWF compared to HWF. The overall trends of stickiness is lower with the MAG gel compared to the mixture, which demonstrates an interaction between structure and protein quality.

Figure 6: Resistance to extension values determined by Texture Analysis for HWF or SWF and 0, 6, 12, 18 or 24% lipid addition. SWF values are similar to control until 18 and 24% lipid addition. Resistance to extension parameters mimic dough development times in HWF. MAG gel and mixture have similar resistance to extension parameters except when their development times differ at 18% addition in HWF.

Figure 7: . Gluten Peak Tester values for the time in which the flour lipid mixtures reach maximum gluten development, referred to as peak max time (PMT). The PMT values for the MAG gel and mixture do not follow the same trend as lipid content increases, because of the difference in the functionality of their components and the flour differences in protein quality and quantity.

Conclusions

The functionality of the water, oil and monoglyceride components in the MAG gel is not similar to the same components when added individually in an unstructured format.  There are significantly different interactions between the MAG gel and HWF and SWF likely because of the interactions of their protein components and starch.  Further research is necessary to identify why the structured MAG gel behaves differently than its individual components, and how gluten and/or starch contribute to the variations observed in these behaviours.

Alejandro G. Marangoni
Department of Food Science, University of Guelph, Guelph, ON N1G2W1, Canada

Increasing public concerns over excessive saturated and trans fat intake from manufactured food products has lead to the search for alternative strategies to structure liquid oils into semisolid fats without addition of large amounts of unhealthy trans and saturated fats. Surfactant-like small molecules have been shown to self-assemble into long fibrils, effectively causing oil gelation at concentrations as low as 0.5%. Phytosterols, ceramides, and 12-hydroxystearic acid have been shown to be effective organogelators. Liquid oils can also be structured by microencapsulation within multilamellar vesicles, with walls composed of monoglyceride hydrates in the alpha-gel state. The surface potential of these monoglyceride vesicles is then adjusted so as to maximize inter-vesicle interactions and the formation of a cellular solid with oil-filled cells. These monoglyceride gels have recently been proven to have excellent functional characteristics in baking applications as well as for omega-3 oil stabilization. High-molecular weight polymers such as ethylcellulose have also been successfully used by our group to gel oil in the absence of water. This development of a polymer-stabilized organogel is very promising since these polymers are widely available and are food-grade. The development of a new way to make fat exploiting the self-assembly properties of food-grade molecules is at hand.

Keywords: Organogels, polymers, cellular solid, alpha gel, monoglycerides,shortening substitute.

INTRODUCTION

Diets high in trans and saturated fats have numerous deleterious health effects ranging from adverse effects on lipoprotein (cholesterol) profiles, increased incidence of heart disease and metabolic syndrome [1]. By 2010, it is projected that in excess of 230 million people will be affected with metabolic syndrome, a diet related disease, associated with an elevated risk of developing type II diabetes mellitus, cardiovascular disease and premature death [2].

Negative health implication associated with consuming trans and saturated fats may be reversed by altering the intake of these heart unhealthy fats and replacing them with polyunsaturated fats. It is estimated that replacing 5% of our daily energy intake from saturated fats with either equivalent energy from carbohydrates, mono- or polyunsaturated fats would be associated with a decreased risk of CVD in the range of 22 to 37% [3].

In an attempt to curb these diet related epidemics, governments across the globe are passing aggressive legislation to limit and in some cases ban the use of trans fats. Denmark was the first country which restricted the amount of trans fatty acids in industrially produced fats and oils to 2% (w/w) or less (Danish order no. 160 of March 2003). The United States’ Food and Drug Administration and the Canadian Food Inspection Agency enacted mandatory labeling of trans fatty acid content in food products in January of 2006, for any products containing more than 0.5g of trans fatty acids. As well, California and Connecticut recently passed state legislation banning all artificial trans fats from food products (CA AB 97, 2008, enacted, Chapter No. 207). Florida has proposed restrictions on trans fats in schools via the “Florida Healthier Child Care and School Nutrition Act”; and state after state are considering enacting “hard-line” legislation restricting or banning trans fat [4].

The American Heart Institute believes even greater restrictions are necessary advocating that no more than 10% of daily energy should be consumed in the form of trans AND saturated fats combined [5].

With this in mind, it becomes more evident than ever that novel technologies need to be implemented in an attempt to curb the associated epidemics and to address the gigantic food manufacturing problem this will represent.

In order to fulfill these new legislative requirements, the food industry must vigorously investigate alternatives to traditional triacylglyceride (TAG) structuring. TAGs provide structure in numerous food products including ice cream, cheese, butter, lard, etc.

Unfortunately, it is the trans and saturated lipids which provide the structure and solid-like properties of these foods. Although the structure they confer on products is desirable, and indeed required, in many products, both types of fatty acids have been shown to deleteriously influence human health.

Since it is the hardstock TAGs that responsible for network structure, it is often difficult or impossible to eliminate these ingredients in order to improve the health characteristics of a food product without sacrificing some of the quality characteristic associated with that particular food product.

Food manufacturers are very reluctant to change the characteristics of successful industrially produced food products to any extent!

Thus, the task of replacing a major ingredient responsible for many of the quality attributes of a food product is a very difficult task, and an even harder sale.

Pernetti so eloquently states that finding alternatives to TAGs with healthy properties, versatility and performance is a tremendous challenge [6].  Without being overly critical of the food manufacturing industry, the “solution” to replacing trans fats adopted by industry has been the replacement of partially hydrogenated fats with saturated fats from palm “oil”.

Palm oil is a misnomer since it should, by definition, be referred to a palm “fat”, since it is solid at room temperature (20-25oC).

This is obviously true for palm kernel “fat” and coconut “fat” as well. Calling these materials “oils” is not correct and should not be encouraged. For the record, the fatty acid composition of palm fat is included in Table 1 below.

Table 1: Fatty acid composition (% w/w) of palm fat

Source: Firestone, Physical and Chemical Characteristics of Oils, Fats, and Waxes, AOCS Press, 1999

Of particular concern is the high content of palmitic acid (16:0), which has been shown to be the most atherogenic saturated fatty acid [7,8].

The aim of this review is to examine strategies for replacing colloidal fat crystal networks comprised of trans and saturated fats including small-molecule organogels of unsaturated oils, structured oil-in-water emulsions and polymer gels. This short paper is not meant to be an exhaustive review, but an overview of the work carried out in our laboratory.

STRUCTURED EMULSIONS

At the core of this technology is the creation of an oil-in-water emulsion stabilized by hydrated saturated monoglyceride multilayers. These multilayers are composed of monoglyceride bilayers with large amounts of water “sandwiched” in between.

The monoglyceride bilayers are formed at temperatures above their Krafft temperatures, and are in the L-alpha state. Upon cooling, the fatty acid chains of the hydrated monoglycerides crystallize into a hexagonal conformation ( alpha subcell polymorph) to an L-beta phase. A co-surfactant is added along with the saturated monoglyceride to enhance the formation and stabilization of this, so called, alpha-gel state.

At the same time as these 9hydrated monoglyceride multilayers are formed, oil is added to the system and exposed to an external shear field. A monoglyceride monolayer then surrounds the oil droplets upon which the multilayers can deposit. Thus, in the end, the oil becomes encapsulated within hydrated monoglyceride multilayers, forming and oil-in-water emulsion.

Upon crystallization of these multilayers, the oil becomes effectively microencapsulated within hydrated crystalline spheres. By adjusting the surface charge of the vesicles by judicious addition of a charged co-surfactant and/or medium pH adjustments, it is possible to fine-tune vesicle-vesicle interactions to create a range of rheological behaviors, from liquid to solid and also prevent the Lβ to Lβ’ transformation [9-12]. Figure 1 summarizes this structured emulsion technology.

Figure 1: Principle behind the technology involved in the creation of a structured oil-in-water emulsion that can be effectively used as an all-purpose shortening.

Figure 2: Polarized light micrograph of a cellular solid composed of hydrated crystalline monoglyceride walls where liquid oil is encapsulated within the cellular lumen.

This structured emulsion, now a commercial product marketed under the brand CoaSunTM can be very effectively used as an aloo-purpose shortening substitute to manufacture a variety of bakery products, particularly cookies, cakes, scones, muffins, waffles, among many others.

The great advantage of these materials is its very low saturated fatty acid content, which makes it possible to both manufacture healthier food products and also make claims on food labels.

If prepared with rapeseed oil, CoaSunTM will contain between 7 and 8% total saturates and can usually replace traditional shortenings on a 1:1 basis [13].

Moreover, it is possible to encapsulate and partially protect omega-3 fatty acids effectively using this shortening alternative technology.

Limitations of these oil-in-water structured emulsions are the fact that water is present (30-40%) in the material and baking parameters have to be adjusted accordingly.

On the other hand, this represents a net decrease in the total amount of fat used and thus consumed. This is another advantage from an economic and nutritional point of view.

ORGANOGELS

An organogel can be defined as an organic liquid entrapped within a thermo-reversible, three-dimensional gel network. This gel network is formed by the self assembly of a relatively low concentration of organogelator molecules into long crystalline fibers (Figure 3), and is thus called Self-assembled fibrillar networks or SAFINs.

Figure 3: Polarized light micrograph of a 12-hydroxystearic organogel at 2% (w/w) concentrations in rapeseed oil. Notice the alternating dark and bright areas indicative of a helical twist in the fibers.

 Organic solvents can actually be gelled at organogelator concentrations as low as 0.5%. Depending upon the chemical properties of the organogelator, gels can be formed from organic solvents (benzene, hexane) or liquid oils.

The wide variety of both current and future applications of organogels has been outlined in two comprehensive reviews [14,15]. While some industries are already making use of organogel technology, many of its potential applications are still in the research and development phase.

The potential applications of organogels in food system are numerous and offer a revolutionary option for nano and microstructuring edible oils into functional fats. A number of organogelator systems have the ability to gel edible oils at very low concentrations (0.5-2.0% wt). General categories of network-forming edible oil structurants include: Triacylglycerols (TAGs), Diacylglycerols (DAGs), Monoacylglycerols (MAGs), fatty acids, fatty alcohols, waxes, wax esters, sorbitan mono-stearate; as well as the following mixtures: fatty acids and fatty alcohols, lecithin and sorbitan tri-stearate, and phytosterols and oryzanol [6]. More specifically, the following organogelators or mixtures thereof are well-known for their ability to structure in edible oils: 12-hydroxystearic acid [14,16-20], ricinelaidic acid [21,22], candelilla wax [23], mixtures of β-sitosterol and γ-oryzanol [24], mixtures of stearic acid and stearyl alcohol [25,26], and mixtures of lecithin and sorbitan tri-stearate [27], and more recently mixed ceramides [28]. Regardless of the network composition, organogels have numerous potential different functionalities in food products including (but not limited to): the restriction of oil mobility and migration, the replacement of saturated and trans- fats, the stabilization of emulsions, and the ability to control the rate of nutraceutical release. Figure 4 shows one of the most promising applications of these organogel systems, the purely physical stabilization of water-in-oil emulsions. This emulsion gel was stable for over a month at room temperature conditions regardless of the large size of the water droplets. The birefringent network of 12-HSA fibers can be appreciated throughout the continuous oil gel.

The greatest challenge in this field is to find an organogelator that is food grade and that offers a functional advantage. The phytosterol-oryzanol system developed in Bot’s group is the most promising system in this respect. On one hand, the material forms optically transparent gels structured by crystalline nanotubes of 7nm diameter [29], while also having the added value of the proven cholesterol-reducing properties of phytosterols. Even though the work is still at a preliminary stage, the ceramide system developed in our group follows in the footsteps of the Bot’s phytosterol-oryzanol work – self-assembled fibrillar network structuring and a powerful pharmacological effect.

Figure 4: Polarized light micrograph of a 12-hydroxystearic organogel at 2% (w/w) concentrations stabilizing large water droplets. Notice the birefringent fibers in the continuous oil gel phase.

INTERESTERIFIED HIGH-STEARIC ACID FATS

Interesterification, either chemical or enzymatic, can improve the functionality and physical properties of fats and oils [30]. This method can replace hydrogenation as a major source of trans fatty acids (TFA) and has been a primary tool in the creation of plastic fats for baked goods [31]. Reducing the dietary intake of trans fatty acid has been recommended by various scientific studies, as well as public and regulatory policy [32,33]. For example, the American Heart Association recommends that the intake of TFA be less than 1% of total daily energy [34]. A recent study showed that a 2% increase in energy intake in trans fatty acids forms was associated with a 23% increase in the risk of incidence of coronary heart disease [33].
In order to achieve a similar functionality in fat product as hydrogenated fat, a saturated hard stock such as fully hydrogenated rapeseed oil or fully hydrogenated soybean oil rich in stearic acid can be used. Early studies of Hegsted et al. [35] and Keys et al. [36] noted that stearic acid (18:0) has a neutral effect on serum cholesterol levels. Another study examined the effect of cocoa butter and structured fat with high stearic acid content and showed that stearic acid elicits a hypocholesterolemic effect compared with other saturated fatty acid [37]. More recently, the work of Mensink et al. [7] strongly suggests the stearic acid does not affect lipoprotein metabolism to a significant extent. Furthermore, consumption of oleic acid has been shown to have beneficial effects on human health, such as decreased vulnerability of plasma low density lipoprotein (LDL) to oxidation [38]. Moreover, oleic acid is stable towards oxidation relative to linoleic and linolenic acids [39,40].

Thus, a possible strategy for structuring food products less harmful fats is to use mixtures of fully hydrogenated vegetable stocks with high-oleic acid oils. However, these fats tend to have a very poor functionality and thus interesterification using sodium methoxide or lipases is necessary.

Figure 5 shows the solid fat content vs. temperature profiles for non-interesterified (NI), chemically interesterified (CI) and enzymatically interesterified (EI) mixtures of 30% fully hydrogenated canola oil in high oleic sunflower oil. The enzymatic interesterification was carried out using a random lipase from Candida antartica.

Figure 5: Solid fat content vs. temperature profiles for 30% mixtures of fully hydrogenated canola oil in high oleic sunflower oil (CI: chemically interesterified, EI:enzymatically interesterified; NI:non-interesterified).

The SFC-temperature profile of the interesterified samples suggests a much more functional fat. Moreover, the NI crystals were in the β polymorphic form, while the EI and CI samples were in the β’ form [41,42]. It is evident, thus, that these mixtures require a chemical randomization of the fatty acids on the TAG backbone in order to be functional in food applications.

Figure 6 shows the changes in the storage modulus G’ (A) and Yield Force (B) upon chemical and enzymatic randomization of some of the mixtures. The increase in G’ and yield force of the chemically interesterified samples was due to a decrease in crystal size [43].

Figure 6: Changes in the storage modulus (G’) and yield force due to chemical (CI) and enzymatic (EI) interesterification of mixtures of fully hydrogenated canola oil (FHCO) and high-oleic sunflower oil (NI).

POLYMER ORGANOGELS

In this author’s opinion, this is the next frontier of liquid oil structuring. There is a wide availability of food-grade polymers (polysaccharides, proteins) that could fulfill the promise of gelling oil. Being a frugal industry by nature, this “cheap” structuring of oils should help the implementation of these new technologies in the marketplace.

Currently, many biopolymers are being assessed in our laboratory for their potential as organogelators at concentrations below 10%.

Figure 7: Polymer organogel of ethylcellulose in vegetable oil. The fat of the future!

 Very little published work is available on this topic. We could only identify one paper on the gelation of ethylcellulose-oil mixtures into a plastic solid by addition of olive oil-derived surfactants [45]. The motivation for this work was the creation of a cream for the topical delivery of pharmaceuticals.

CONCLUSIONS
In this work we have presented some of the most promising strategies for structuring liquid oils. The motivation for this work is to create a semisolid structure with the functionality of fats, but with the nutritional profile of liquid oil – low in saturates, devoid of trans fatty acids and possibly containing some nutritionally beneficial fatty acids. Structured emulsions, SAFINs, polymer organogels and high-stearic acid fats will all be part of the solution to the problem of improving on the nutritional quality of our manufactured food products, in consideration of sensory quality and price.

ACKNOWLEDGMENTS

The author acknowledges the financial assistance of the Natural Sciences and Engineering Research Council of Canada, the Ontario Ministry of Agriculture and Food, the Advanced Food Materials Network, the Canadian Foundation for Innovation and the Canada Research Chairs Program. The author would like to thank Dr. Michael Rogers and Ms. Naomi Hughes for help with the manuscript.

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Sarah Langmaid, Carolyn Challacombe, Brittany Huschka, Steve Bernet, Alejandro Marangoni
CoaSun Corporation and University of Guelph, Guelph, Ontario

from a presentation presented at the University of Guelph Human Nutraceutical Research Unit

The Trans Fat Problem
Obesity and cardiovascular disease are of increasing concern to Canadians. 26% of young Canadians are overweight or obese. Many preventable diseases are associated with being overweight or obese including: cardiovascular disease, joint problems, and type II diabetes which can lead to premature death (Merrifield, Rob. 2007. Healthy Weights for Healthy Kids. Report of the Standing Committee on Health. 39th Parliament 1st session).

The Canadian Heart and Stroke Foundation the American Heart Association, the Institute of Medicine, among many others, have strongly recommended a reduction in the amount of trans and saturated fats in our diets. Trans fats have a double negative effect on cardiovascular health by increasing LDL (the bad) cholesterol while decreasing HDL (the good) cholesterol.

The Challenge
Despite the recommendations that Canadians reduce the amount of trans fats in their diets many snack foods rely on trans fats for their functionality and industry has yet to find an appropriate fat replacement.

Trans fats are produced from the partial hydrogenation of liquid oils. This results in a plastic fat with a higher melting point and improved resistance to oxidation, which increases the shelf life of both the fat and the final product. A replacement must share the functionality of these trans fats to maintain the product convenience and quality consumers expect.

A popular solution is to replace trans fats with saturated tropical oils, such as palm oil; however, this is not a long term viable solution for health as tropical fats have significant amounts of atherogenic saturated fats.

The CoaSun Solution
By physically structuring liquid oils and forming a semi-solid paste, much of the functionality associated with trans fats can be maintained, while improving nutritional profiles. Any vegetable oil or blend of vegetable oils with other fats can be used to make the material.  Nutraceutical products can also be manufactured by adding oil soluble adjuncts, such as vitamin E and phytosterols, to the oil phase. The health benefits of the shortening reflect the type of oil used.

 The Coasun material is structured by crystallized liquid crystalline monoglyceride mesophases and has been shown to have remarkable baking functionality. Above its Krafft temperature, monostearin liquid crystalline phases can be used to stabilize oil in water phase inverted emulsions. Oil is sheared in the presence of the self-assembled liquid crystalline phase to form multilayers around the newly formed droplets. Upon cooling, the multilayers crystallize forming crystal hydrates called alpha-gels and upon dehydration, beta-gels (or coagels). Electrostatic interactions are then adjusted to induce the aggregation of the solid droplets, resulting in a cellular-solid like structured material.

Figure 1. A) Confocal laser scanning micrographs of COASUN, where lipids are stained with Nile Red and water with coumarin (blue). B) Polarized light micrograph of COASUN showing birefringent monoglyceride cell walls surrounding oil droplets.

Benefits of Coasun
Economy:
By utilizing oils derived from locally grown crops to produce a functional shortening for baked goods, we are able to stimulate local agriculture, the agri-food industry and rural economies, and limit the exponential growth in offshore tropical fat imports.

Health:
Since the material contains zero trans fats and is very low in saturates all of the allowed (Canadian) nutritional claims that are tied to saturated fat content of the food can be made. The nutritional profile of the shortening can be seen in Table 1.

 The unique structuring of the oils gives CoaSunTM additional metabolic advantages. These include an attenuated increase in blood triglycerides and free fatty acids, as well as an attenuated increase in insulin levels after acute consumption of CoaSunTM.

Figure 2. Changes in serum triacylglycerol (A), free fatty acids (B), glucose (C) and insulin (D) levels after acute consumption of COASUN shortening alternative (mag gel) relative to compositionally equivalent oil-water mixtures (oil).

 Applications of Coasun
The cellular solid matrix imparts exceptional tribological (lubrication and coating) characteristics during mixing, creaming (air incorporation and stabilization, water binding and emulsification characteristics, making it ideal as a trans fat free shortening alternative. Extensive studies and testing have demonstrated that Coasun can substitute ordinary shortenings and bakers’ margarines in muffins, cakes, cookies, brownies, scones, tea biscuits, pie and tart shells and biscotti with no quality compromises.

Figure 3. A pie shell (A) and a croissant (B), made with Coasun as the shortening. A dollop of Coasun (C) next to a ball of pie dough with Coasun incorporated as the shortening (D).