Fat That’s Fit for Oven and Fryer

February 2003

Fat That’s Fit for Oven and Fryer

By Donna BerryContributing Editor

Many of today’s consumers no longer fear fatty foods like they did less than a decade ago. While this can be viewed as a good thing — humans need fat in their diet for the body to properly function — it might also be considered bad. After all, the Surgeon General reports that 61% of U.S. adults and 13% of U.S. children are considered overweight, rates that have doubled for adults and tripled for children since 1980. With consumers’ fear of fat subsiding, these numbers are threatening to further increase.

While developers know that fats and oils add functionality and mouthfeel to products, the health and label concerns paired with these ingredients have caused manufacturers to find new ways to formulate fat into products. New advancements in technology have led to improved ingredients and revamped formulations, bringing health and functionality closer together in today’s baked goods and snack foods.

Trans talkWithin the food-manufacturing industry, particularly in the bakery and snack-food businesses, today’s fat buzz centers on mandatory trans-fat labeling. Levels of trans fatty acids tend to be quite high in baked and fried foods due to required functionalities that, until recently, were only available from either trans-containing fats and oils, or saturated fats and oils, both of which are viewed by the health-profession community as “bad fats.”

In fact, this past summer, the National Academy of Science’s Institute of Medicine (IOM), Washington, D.C., issued a report warning that consumers should reduce their intake of trans fats as much as possible. This is because intake of trans fats is directly associated with an increase in total and low-density lipoprotein (LDL) cholesterol levels (bad cholesterol), and therefore increases the risk of cardiovascular disease.

Although the term “trans fats” is often used in this article and elsewhere, it’s really a bit of a misnomer, or at least merely shorthand for “fats that have (a significant level of) trans fatty acids.” trans fatty acids are the trans isomer of unsaturated fatty acids, fatty acids that contain a double bond between two carbon atoms. Most naturally occurring unsaturated fatty acids are in the cis isomer form. trans and cis refer to the positioning of the hydrogen atoms around the double bond. When hydrogen atoms are on the same side of the double bond, they are in the cis position and the chain appears bent. When the atoms are on opposite sides, they are in the trans position and the fatty acid appears straight, resembling a saturated fatty acid. Thus, trans fatty acids behave somewhat like saturated fatty acids. For instance, they can pack compactly together, producing a more-stable and slightly harder fat than cis fatty acids.

Trans fats appear in foods for two reasons. Either they are naturally occurring, as in the case of some fats derived from ruminant animals, such as cattle and sheep, or they are added through the inclusion of hydrogenated fats and oils. Hydrogenation increases the oils’ stability by adding hydrogen atoms to the double bonds on unsaturated fatty acids, as well as by reconfiguring other double-bonded hydrogens on unsaturated fatty acids from the cis to the trans position.

Because of the negative health implications associated with consuming these fats, FDA has been working on the issue of labeling the trans fat content of foods. The current position is that there should be no limit specified for the Daily Value; however, to assist consumers with heeding IOM’s suggestion, the FDA is attempting to make it mandatory for food manufacturers to quantify trans content on a separate line on food labels, and include a mandatory footnote stating IOM’s recommendation.

“While the whole issue of trans fats can be complex to consumers, the message to keep trans fat as low as possible in the diet is fairly straightforward,” says Ruth Isaak, communications director, National Sunflower Association, Bismarck, ND. “Consumers will be able to identify products containing trans fats when labeling of them is required on Nutrition Facts labels.”

(For more information on FDA’s pending label requirement for trans fats, visit http://books.nap.edu/books/ 0309085373/html/.)

Good fat, bad fatAfter the fat-free frenzy of the ’90s, consumers understand that fat in formulations is necessary for many foods to taste good. One might say that in the ’90s, the fat content in new food formulations was all about removing, while these early years of the new millennium are all about improving.

The food industry needs to be responsible with this shift from de-emphasizing total fat content to promoting better-for-you fat contents. It could backfire in a few years, deeming everyone’s reformulation efforts futile.

For instance, there exists the possibility that Plano, TX-based Frito-Lay, Inc.’s recent reformulation of Doritos, Tostitos and Cheetos to eliminate trans fats will give consumers a false sense of good nutrition, similar to the fat-free cookie syndrome brought on by Glenview, IL-based Kraft Foods, Inc.’s SnackWell’s during the fat-free craze. After all, if consumers eat a whole bag of Doritos — regardless if they are trans-free or not — they are still eating a heck of a lot of fat grams. Frito-Lay, though, is in the snack-food business, so praise is due for the attempt to improve the nutritional profile of fried chips by replacing hydrogenated oils with trans-free corn oil.

Reducing fat, along with using nonhydrogenated fats, is probably the safest marketing approach when it comes to making tasty, better-for-you bakery and snack foods. As a result, companies such as Hershey Import Company/Harvest Bay, Edison, NJ, are out to do just that. “We wanted to develop a snack that was healthy but, at the same time, tasted sinful,” says Eric Zitelli, president.

The company manufactures all-natural chips and sticks made from carrots, green beans, squash, taro, sweet potatoes, red sweet potatoes, and radishes. The products are vacuum-fried in 100% nonhydrogenated canola oil, and contain no saturated fat and no trans fats. The vacuum-frying process is highly specialized. Advanced cooking kettles first draw a vacuum in a chamber and then inject a mist of heated oil around the raw product, cooking the vegetables faster and at a lower temperature than conventional fryers. Vacuum-fried snacks absorb less oil, and retain more of their natural colors and flavors due to the reduced cooking time and lower temperature. “Vacuum-fried snacks give you the satisfying crunch of other fried snacks, but taste less greasy and contain less fat,” Zitelli says.

Role playingFats and oils play a variety of roles in baked and fried foods. For instance, with baked products, fats and oils make the crumb in cake soft and easy to chew. Fats and oils also provide lubricity and moistness during manufacturing and consumption, as well as pliability, rise, flakiness, strength and airiness during product manufacturing.

In frying, oil acts as a heat-transfer medium, moving energy, in the form of heat, into the food and pumping a portion of the water out. This is how potato slices become chips. In essence, they are dried out by heat and oil.

Snack chips are fried in slightly hydrogenated liquid oils to increase stability to oxidation. Frying a chip in hard, high-melting fat gives it a glassy appearance and undesirable waxy mouthfeel. Just the opposite is true when frying dough to make doughnuts or pastries. In this application, harder shortenings are preferred, as liquid oils may cause coatings or glazes to crack because the fats do not solidify in the same manner as harder fats.

Some manufacturers who know that their baked and fried foods currently score high in trans content are trying to eliminate or reduce trans from formulations by replacing some or all of the current fats and oils with trans-fat-free fats and oils. The frenzy in some labs mimics what happened about 10 years ago when highly saturated “tropical” oils were found to contribute to heart disease. At that time, processors scrambled to reformulate with less-saturated fats.

Tropical oils, as well as butter, beef tallow and lard, were previously preferred over vegetable-sourced oils for industrial and foodservice baking and frying applications, as these fats have excellent stability and provide exceptional flavor to baked and fried foods. Unfortunately, these fats are highly saturated, and saturated fats have been linked to raising blood cholesterol levels, and thus, an increasing risk of heart disease. As a result, manufacturers reformulated many foods with vegetable oils, but these fats required partial hydrogenation in order to increase shelf life, enhance stability against oxidation and improve heat-stability, particularly in frying applications.

In essence, trans fats increased in the diet when the food industry responded to the health community’s call to reduce saturated fats in prepared foods. Without hydrogenation, manufacturers found that most vegetable-based fats and oils spoiled quicker than saturated fats, could not withstand the high heat used in deep fryers, and made the batter and/or dough of many baked products runny.

Interestingly, even though manufacturers went through all those efforts to reformulate saturates out and now are doing the same by replacing hydrogenated fats, according to a random telephone survey of 1,000 consumers conducted for the United Soybean Board (USB), St. Louis, consumers are still very confused as to what is better for them — trans fatty acids or saturated fats.

“Not surprisingly, consumers continue to show confusion about the health profile of fats and oils,” says Diana Steeble, USB spokesperson. “While 90% of consumers recognize that saturated fats are unhealthy, most remain uncertain about unsaturated fats, with nearly half perceiving mono- and polyunsaturated fats as unhealthy. In contrast, consumers are much more sure about omega-3 fatty acids, with 67% stating that they are healthy.” However, for the baking and snack-food industries, omega-3 fatty acids (linolenic polyunsaturated fatty acid, which contains three double bonds) are highly unstable and require hydrogenation for use in high-heat applications.

“While standard canola and soybean oil have healthful fatty-acid profiles for home use, they are almost always hydrogenated when used commercially because the linolenic acids they contain render the oil unstable under intense heating and frying conditions,” says Isaak. “Olive oil, on the other hand, has a high monounsaturated-fat profile and is relatively stable because it is low in linolenic acid. However, olive oil smokes at a low temperature and can impart a distinctive flavor to foods, two characteristics that do not complement bakery and snack foods.”

Reformulating efforts“All too often, trans-fat-reduction questions and discussions focus exclusively upon the fat ingredient and how it can be changed,” says Bob Wainwright, director of technical service, Cargill Refined Oils, at the company’s C+T subsidiary in Charlotte, NC. “However, with baked goods and fried foods, all the ingredients interact to deliver the final eating experience, and changing a single ingredient or process variable can have significant implications for the final product characteristics.”

After all, some of the other ingredients that go into the bakery and snack formulas contain fat. Some may even contain trans fatty acids (whether from hydrogenated fats or naturally occurring), such as cheese powders on snack chips and cream cheese in cheesecakes. “Formulators must evaluate the total system, and not just look at replacing the fat ingredient,” Wainwright says. “Successful reformulation requires close collaboration between ingredient and end-user product-development teams.

“Many bakery applications rely, at least in part, on the shortening component contributed by saturated fats, trans fats or a combination of both. These fats provide structure, stand up, aeration, creaming and mouthfeel,” continues Wainwright. “Therein resides the technical hurdle to many reformulation efforts. This also represents a key decision that the baker must make. Are elevated saturates an acceptable tradeoff for a reduction in trans?”

Wainwright explains that some fundamental questions require answers to determine the appropriate solution pathway. These include, but are not limited to:• What is the upper limit when quantifying trans-fats per serving?• What is the timeframe for achieving this label declaration?• Can finished-product characteristics be changed to facilitate the solution?• Is the process flexible?• What types of fats and oils are permissible on the ingredient statement?• What solution premium can be invested by the company to support and/or defend the brand?

“We are often approached with a preconception that a cost-neutral, turnkey ‘magic bullet’ is available,” Wainwright says. “Unfortunately, this is rarely the case. In general, input costs, in terms of value-added raw materials, and often, additional processing steps, necessitate premiums for many reduced-trans options.”

Dennis Tagarelli, director of business development, HUMKO Oil Products, Memphis, TN, says: “Basically, our approach is to look at total fat in the current application. Seldom is there only one fat in a food system. Formulators must analyze what fats are in the food system, determine which ones are contributing to trans fat content, calculate how much trans fat is coming from which fats and, finally, determine the role of each of the fats. It is a full-system approach. The nice thing is that there is flexibility. After all, even if the goal is to label a food as containing no trans fats — that is, on a per-serving basis, the maximum allowed trans fats per serving to make a zero claim is less than 0.5 grams. Also, total saturated fat must be less than 0.5 grams per serving.”

This means it is possible to formulate a zero-trans-per-serving bakery or snack food and still use some hydrogenated fat in the formula for necessary functionality. It simply gets diluted by the other ingredients and in the final calculation, is less than 0.5 grams per serving. This is why it is also important to determine how critical labeling of fats and oils is on the ingredient statement.

Finding the right fat In efforts to improve trans-fat declarations on food labels, food formulators are evaluating a variety of new industrial oils. Many of these are the result of innovative and carefully controlled, nontransgenic oilseed crop-breeding programs that attempt to increase monounsaturated-fatty-acid levels while lowering levels of highly unstable linolenic acid. Such seeds include low-linolenic canola, high-oleic canola, high-oleic sunflower, mid-oleic sunflower, low-linolenic soybean and high-oleic soybean. These seeds yield specialty oils that do not require hydrogenation for commercial frying applications — one of the harshest tests to determine oil’s stability.

Within the trans-fat-free specialty-oil category, oils derived from specific, identity-preserved oilseed crops often become product-application specific. For example, high-oleic canola oils can come with a fatty-acid profile of 74% oleic acid and 12% linoleic acid. This oil works well for shelf-stable applications, as its unique fatty-acid composition delivers a neutral oil flavor and extended product stability. There’s also high-oleic canola oil with a 65% oleic-acid and 22% linoleic-acid profile. This oil is for high-heat applications, such as frying. The unique fatty-acid application provides superior fry stability for the oil, as well as improved fried flavor in the food. Wainwright notes that some high-oleic canola oils not only eliminate trans fatty acids, but offer a low saturate content, as well.

Mid-oleic sunflower oil works exceptionally well in fried snack-food applications. Procter & Gamble (P&G), Cincinnati, has been using NuSun™ mid-oleic sunflower oil to manufacture Pringles potato crisps since 2000. Prior to switching to the oil, P&G determined that mid-oleic sunflower oil —which has been sold as a commodity oil since 1999 from a variety of industrial-oil ingredient suppliers and was developed by USDA using standard breeding techniques — offered clean flavor attributes and a lower saturated-fat content than other oils evaluated. It also met all the company’s requirements for shelf life, total polar compounds, oleic content, process reliability and overall stability.

On average, mid-oleic sunflower oil contains about 9% saturated fat, 65% monounsaturated fat (oleic acid) and 26% polyunsaturated fat (mostly linoleic acid). “Having only a trace of linolenic acid, this mid-oleic sunflower oil does not require hydrogenation, eliminating any concerns over trans fats in baked and fried foods,” says Isaak. “It works extremely well in industrial cooking and frying applications, with a smoke point of 450º F and a clean, light taste.”

Tagarelli adds that the company’s high-oleic sunflower “contains the highest percentages of monounsaturated fatty acids among oils that have application in bakery and snack foods. It is about 82% oleic acid, with only 9% linoleic acid. Recent studies have shown that monounsaturated fatty acids have a positive effect on LDL.”

The USB is in the midst of the Better Bean Initiative, an effort designed to bring soybean varieties with enhanced characteristics to the marketplace. Trait enhancements include lowering the saturated-fat content of soybean oil, while, at the same time, reducing or eliminating the need for hydrogenation in high-heat commercial applications by increasing oleic-acid content and reducing linolenic-acid content. “As new varieties are cultivated, harvested, tested and ultimately commercialized, they will have to meet a set of standards before they can be identified as part of what will be known as the Qualisoy™ family of soybeans,” says Steeble.

For bakers wanting to lower trans fats, “We’ve developed a new reduced-trans shortening that enables food processors to positively improve fat profiles on Nutrition Facts panels while maintaining superior quality,” says Frank Kincs, director R&D, Bunge Foods, Bradley, IL. “This revolutionary technology produces a reduced-trans product with the functionality of traditional shortening, which enables the delivery of high-quality baked goods.” He notes that the shortening, derived from soybean and cottonseed oils, consists of less than 4% trans fat with no change in the amount of saturates. He adds that the product’s level of solid fat is similar to standard shortening. Traditional shortening is about 25% to 29% trans fats and 25% to 29% saturated fats.

“This reduced-trans fat shortening has been evaluated in a wide range of applications, and performance and handling has been found to be comparable to the control,” Kincs says. “Little difference in the end product was noticed in all-purpose applications, such as chocolate chip and sugar cookies, pie crust, and biscuits. In more stressful situations, such as white, yellow and devil’s food cakes, the test product was very close to the control.”

Simply different fatAnother option for baked foods is the lower-calorie fat salatrim, an acronym for short- and long-chain acyl triglyceride molecules.

Sold under the name Benefat® by Danisco USA, Inc., New Century, KS, Terese O’Neil, business director for Benefat, notes the product “is a solution to meet consumer demands for trans-fat-free formulations without complicated reformulation.” She calls it “a true fat in a shortening form, yet trans-free. It is particularly well-suited to the bakery industry.” Dana Boll, bakery technical manager at Danisco, adds that the ingredient “functions like a typical shortening in a formulation and substitutes for current fats. It creams into a bakery, cookie or nutrition-bar mix, yet is very stable to oxidation.”

In addition to its trans-fat-free benefit, salatrim only delivers 5 kcal/gram instead of the 9 kcal/gram found in traditional fats. This is because it is a mixture of triglycerides that consist of at least one long-chain and at least one short-chain fatty acid per triglyceride molecule. The lower caloric content is possible because the short-chain fatty acid is naturally lower in calories and is actually metabolized like a carbohydrate. In addition, the product’s unique composition prevents the long-chain fatty acid from being fully absorbed by the body; thus, the lower caloric content.

Somewhat similar in concept to salatrim, Enova™ oil is making its way to the United States from retail Japanese markets, where it has been sold under the brand name Healthy Econa™ cooking oil since 1999. Manufactured and marketed by ADM Kao LLC, Decatur, IL (a joint venture between Archer Daniels Midland Company [ADM], Decatur, IL, and Kao Corporation, Tokyo), Enova oil is unique in that, while it has essentially the same calories and fat content as the soy and canola oil that it is converted from, when consumed, more of it is immediately metabolized as energy instead of stored as fat.

“The human body doesn’t treat all consumed fats quite the same,” says Tony DeLio, ADM corporate vice president of marketing and external affairs. The body breaks down consumed fat into fatty acids and a glycerol backbone. These components are absorbed by the intestine and rebuilt into fat molecules that are sent through the bloodstream for storage in body tissues. However, DeLio notes: “When consumers metabolize the fat in Enova oil, less triglycerides appear in the blood than when traditional cooking oils are consumed because more of the fat in Enova oil is burned as energy in the liver, rather than transported to the fatty tissue for storage in the body. This is a result of the number and position of fatty acids carried on the glycerol backbone of Enova oil.”

Traditional cooking oils consist mostly of triglycerides, with a small amount of diglycerides. Enova oil consists mostly of diglycerides. Triglycerides carry a fatty acid on all three available positions on the glycerol backbone molecule, while diglycerides carry only two fatty acids — either one in the first and second positions (1,2) or in the first and third positions (1,3). The fatty-acid number and positioning has virtually no effect on the fat’s functionality in a food system, or the body breaking the fat down and its subsequent absorption by the intestine. What is different is what takes place in the intestine.

“Enova oil consists of 80% diglyceride, with 70% of that amount being the 1,3 form,” explains DeLio. “Due to the shape of the 1,3 molecules, enzymes in the intestine can’t recombine the pieces of this fat into fat molecules, so less fat is passed into the bloodstream to be stored in the body. Since about 56% of Enova oil overall is 1,3 diglyceride, that means the majority of the fats in Enova oil aren’t stored as fat in the body. Instead, the metabolized pieces of this fat are sent to the liver, where they are burned as energy.

“Foods made with Enova oil taste just like foods made with traditional oil,” DeLio adds. “Formulators can substitute Enova oil in all cooking and baking applications. Most of the time, there is no need to change processing and mixing parameters. Enova oil is virtually indistinguishable from conventional oils in most product application.” The oil has application in commercial foods that use a liquid source of fat (vegetable or animal) as a raw material. These applications include bakery goods, as well as extruded and baked snack foods. Use of the oil in commercial and foodservice frying applications is currently under evaluation.

“There is nothing artificial about Enova oil, as it is processed from natural soy and canola oils using a biological enzyme to produce as much diglyceride oil as possible,” says DeLio. “The result is identical to the diglyceride oil already found in soy and canola, just at a higher concentration.”

Bakery and snack foods, which rely greatly on fats and oils for functionality and various sensory attributes, are indeed two of the last food groups to be reformulated for the marketplace as more healthful. However, thanks to dedicated scientists and suppliers, it won’t be long before trans-fat-free and other health-related fat claims appear on bakery and snack foods.

Donna Berry, president of Chicago-based Dairy & Food Communications, Inc., a network of professionals in business-to-business technical and trade communications, has been writing on product development and marketing for nine years. Prior to that, she worked for Kraft Foods in the natural-cheese division. She has a B.S. in food science from the University of Illinois in Urbana-Champaign. She can be reached at [email protected].

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