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Trans-Formulation Alternatives
Sometimes it takes a while for health science to catch up to industry developments. In the case of trans fats, the better part of a century passed before scientific evidence clearly demonstrated that the food industry's favorite ingredient, partially hydrogenated oil, was less than healthful, especially in the quantities consumed. Hydrogenation: good and bad From a health standpoint, it didn't help that partially hydrogenated oils became ubiquitous in baked goods, fried foods and a variety of other applications -- particularly after the health reputations of animal and tropical fats were blackened due to their saturated fatty-acid content. But food manufacturers and their customers reaped other benefits. The beauty of the hydrogenation process is that it allows specific attributes to be dialed in depending on the extent of hydrogenation. As the hydrogenation process continues, the oil becomes more solid and plastic and the melting point increases. Custom fats could be created with specific melt points and solids levels. Whipping could incorporate air into shortenings to add volume to baked goods. Before long, partially hydrogenated products were developed for countless food applications, and their cost effectiveness and stability made them indispensable. Rick Francis, vice president marketing, Bunge Oils, St. Louis, remembers discussions about trans about 20 years ago when an anomaly was noted between the health of Americans and Scandinavians. "The American diet was much more heavily into polyunsaturated fats because of margarine compared with the Scandinavian diet, which was much heavier in saturated fat because of butter," he says. "The lower coronary heart disease was in Scandinavia. Nobody could figure it out. What seemed to be the anomaly was the content of trans in the margarine. That's what led people to start looking at it." Two health negatives are working against trans fats: "Not only does it increase the bad cholesterol, or the LDL cholesterol, but also it decreases the good cholesterol, the HDL," notes McNeill. "In the case of saturated fats, in most cases, most saturated fats do increase the LDL cholesterol somewhat, but generally not as much as trans fat. Trans increases the risk of heart disease more than any fatty acid that's known. In the '90s, the data started to flow in from the researchers that trans fat is perhaps even worse than saturated fats." Denmark has completely banned nonanimal trans fats. A similar movement is underway in Canada. In the United States, FDA has ruled that the consumer should be given information to make an informed purchasing decision. By Jan. 2006, all nutritional labels must contain grams of trans fats per serving. "I think that, given where the science is, Food and Drug has made the right decision in terms of providing additional information to consumers so that they can make the very best decisions relative to the sort of choice they opt for in their planning from a nutritional impact perspective," says Bob Wainwright, technical director, Cargill, North America Refined Oils, Charlotte, NC. Yet the question facing the industry is: How much does the consumer understand and how will that affect their food choices? The process of hydrogenation creates trans fats, but a fully hydrogenated fat does not contain any trans because trans cannot exist in a completely saturated fat. Similarly, trans is minimal in a lightly hydrogenated product. Consumers without that knowledge might just react to the term "hydrogenated" on a label. Will they base their food buying decisions on the actual grams per serving of trans, or will they react to the term hydrogenated? "The media's done such a good job of educating the consumer that looks for partial hydrogenation in the ingredient statement that, therefore, it will contain trans fat," says Tom Tiffany, manager food oils research and development, ADM, Decatur, IL. Wainwright notes that many in the industry are trying to determine the consumer perception of the word "hydrogenation" or the phrase "partially hydrogenated." He asks, "Are we going to get a severe pushback if our competition has a similar offering without hydrogenated fat, or is it immaterial to the consumer?" Trans considerations Product designers also need to look at it from a manufacturing-flexibility perspective. "I think all too often the phrase 'drop-in solution' is generally speaking a naive kind of approach," explains Wainwright. "To think that we can simply replace on a 1:1 basis an incumbent system that's new to the overall product and not expect some changes are going to be required whether the way the ingredients are put together initially to makeup, for example, the dough or the way the dough is processed." He continues, "By and large, there's going to have to be a certain amount of give and take in terms of being flexible relative to how we're going to handle this fat system." Line extensions contribute to the dilemma. "If you think about it," Wainwright explains, "over the years, food processors developed core products and then oftentimes built a number of line extensions based on those core products. More often than not, as they expand these core brands, they're going to try their best to stay as much as possible with incumbent ingredients rather than new ingredients for line extensions. Over the years, essentially the finished product and the process -- both on the front side as well as the backside -- have all been optimized around incumbent fat systems, so a lot of effort and energy and developmental work is going into that. As we come in now with a new ingredient in the form of a trans-free or a reduced-trans fat system, you are certainly going to have to expect that a lot of reoptimization is going to have to occur in order to get the most bang for the buck." It's important to remember that trans fats are part of a system and removing trans from the label might require more adjustment than just removing one ingredient. One thing formulators have to be sensitive to is the trans-fat content in the other ingredients besides the oil when they are considering their ingredient statement. "For example, on the oil side, one of the areas we encourage people to look carefully at is the parfry oil," Francis says. Parfrying is a precooking step often utilized in the manufacture of fried fish, fried chicken and french fries. "If an operator wants to say that they have a french fry that has no trans fat in it, if they use just our oils, that may in fact have 0 grams of trans fat per serving on their own," he explains, "but they've got to make sure they then secure products that have been prepared using products that have 0 grams of trans fat per serving, too." Similarly, it's important to consider the presence of naturally occurring trans fat. "Formulators need to be aware that conjugated linoleic acid (CLA) is also a trans fat," says Jill Rippe, R&D director, Main Street Ingredients, Inc., La Crosse, WI. "This is one of several naturally occurring trans fats that gets produced by bacterial enzymes in the stomachs of ruminant animals such as dairy cows. While there is a negative health impact of trans fats produced by industrial hydrogenation, CLA can be purchased as a dietary supplement with potential health benefits including cancer inhibition." CLA is naturally present in milkfat. "CLA is considered a healthy fat and is not included in the definition of trans fatty acids," says Sharon Gerdes, technical support consultant, Dairy Management Inc.(TM), Rosemont, IL. "The FDA defined trans fatty acids as unsaturated fatty acids that contain one or more isolated (i.e., nonconjugated) double bonds in a trans configuration. Trans fatty acids with conjugate bonds, such as CLA, were not included in the final rule because they did not meet the FDA's chemical definition of trans fatty acids." While dairy products are rich sources of CLA, other naturally occurring trans fats are also present. "Products with dairy ingredients have small amounts of natural trans fats in their nutritional profile," Rippe notes. "Low-fat dairy ingredients will contain trace amounts of trans fats and should not contribute significantly to trans fat on a nutritional label." The good news for food formulators is that most dairy ingredients are quite low in trans fats. Two good examples would be nonfat dry milk, which contains approximately 0.03 grams of trans fat per 100 grams, and whey protein isolate, which contains approximately 0.02 grams of trans fat per 100 grams. "In formulations using dairy ingredients, total trans fat will depend on the percentage of dairy ingredients in the formula, serving size and the trans-fat contribution of all the ingredients," says Gerdes. "For more information about the approximate levels of TFA in other dairy ingredients, food formulators can visit DMI's website www.doit withdairy.com. Data there is based on a recent study by the International Dairy Foods Association (IDFA), which tested milk from different regions of the country and weighted these values based on milk production in each region." She notes that the IDFA trans-fat data and DMI website information do not include the amount of conjugated fatty acids, which are not included in the definition of trans fat that the FDA has put into place for labeling purposes. Trading oils Replacing partially hydrogenated oil with corn oil is the approach Frito-Lay, Dallas, took to reduce trans in many of its snack foods. Corn oil is naturally stable. "Typically it's right around 1% or less linolenic acid," Tiffany says. "It has a very nice flavor, and there are snack manufacturers who've used corn oil since their inception because of the flavor that it imparts. It's really nothing new to the industry. It's always been a great frying medium. It's just that partially hydrogenated oils have always been a little cheaper." For potato chips, he suggests using corn oil, cottonseed oil, or mid-oleic sunflower oil. "We've been promoting naturally stable oils as a replacement for partially hydrogenated soybean oil or lightly partially hydrogenated vegetable oil," adds Tiffany. "We feel that these oils can in most cases be drop-in replacements for the partially hydrogenated soybean oil." For some applications, like kettle-cooked potato chips, peanut oil adds distinct flavor and additional crispness. Rice bran oil is another option. It has a less-nutty flavor than peanut oil and is considerably more stable because it naturally contains the antioxidants oryzanol, tocotrienol, and tocopherol. Other oil-substitution possibilities include high-oleic sunflower oil and high-oleic safflower oil. Both are also low in linolenic acid. With a clean flavor, they are very high in heart-healthy monounsaturates. According to Francis, soybean oil represents approximately 80% of the frying volume in the United States. Canola oil represents approximately 9% of the frying volume. Naturally, these two oils possess no trans fats. However, their linolenic content traditionally offers less stability. He sees selective breeding as a means of reducing the linolenic content to create more-stable oils. Bunge has a joint venture with Dow AgroSciences LLC, Indianapolis, to produce a high-oleic canola oil. A partnership between Bunge and DuPont, Wilmington, DE, created the Bunge DuPont Biotech Alliance, which is developing a low-linolenic soybean oil. "The ones we're marketing are done with selective seed breeding instead of genetic modification," Francis explains. "You're breeding the seed and then selecting the ones that have attributes you want and then breeding them again and getting more of those and then planting them rather than genetically modifying the seed." Supply is impacted by the significant time expended in obtaining enough seeds through breeding and converting crops to high-oleic canola or low-linolenic soybean. "They are available, although there is a bigger quantity of the high-oleic canola today than there is of the low-linolenic soybean product. We have a new crop coming in September which will begin to take steps toward evening that out and two to three years down the road the supply side will move much more heavily to the low-linolenic soy. What's important is that soy is an American industry, and you're not going to hold the American farmer down for very long. What the American farmer has needed is low-linolenic oil seed and a market for it. We've got that now, and it's emerging rapidly every day." Francis believes one reason that low-linolenic soy will prevail over the high-oleic canola is the very fact that soy is a domestic crop. "Most of the canola crop comes from Canada," he says. "The growing season is a little bit short, availability is not as high and, consequently, you may see the low-linolenic soy develop from a volume standpoint and move into a broad distribution as quickly as the selective breeding will produce enough seed to produce the kind of acreage necessary to meet the needs of the American food-processing industry, which is trying to move to product with 0 grams of trans fat per serving." Either the high-oleic canola or low-linolenic soy work well for high-heat applications, such as sautéing or frying. However, specific products have been developed for each application. Frying oils require additional processing steps such as deodorization and the addition of antioxidants to improve stability under such rigorous use. Product designers can try another option. Typically, the large oil providers have used hexane as a solvent to extract the oil. Most oils are refined using chemical caustics. Both of these techniques "can degrade the quality of the oil and require partial hydrogenation to add stability back to the oil," says Rob Kirby, vice president marketing, Spectrum Foods, Inc., Springfield, IL. "By contrast, our soybean oil is uniquely expeller pressed and physically refined without the use of hexane or refining caustics. As a result of this unique extraction and refining process, our product offers the stability of partially hydrogenated oil but has no trans fats from hydrogenation. It also provides exceptional flavor when compared to partially hydrogenated oils." He recommends using the expeller-pressed oil for applications such as snacks and IQF par-frying applications as a naturally stable trans-free alternative. Interesterification magic Some semisolid or solid fats are required for critical product attributes. "An example is donuts, where non-hydrogenated oils may 'bleed' out of the product and make the product or packaging appear greasy," says Kirby. In these cases, he notes that product designers can reduce trans fats by using specific blends of oils that do not fully trade trans fats for saturated fats. "We've been utilizing enzymatic interesterification as one means to produce low-trans solid-fat shortening," states Tiffany describing one means of creating solid fats. The process, he explains, starts with soybean oil. This is typically low in trans fatty acids, is a good source of polyunsaturated fatty acids and has about 15% saturated fatty acids. "We take soybean oil and then we blend it with fully hydrogenated soybean oil. When you fully hydrogenate an oil you convert all of the mono- and polyunsaturated acids to saturated fatty acids," he says. Since the hydrogenated soybean oil now contains 99% to 100% saturated fat, there is negligible trans fat. "We're taking two low-trans sources, soybean oil and fully hydrogenated soybean oil, and blending them together at certain ratios. We'll take a certain ratio and blend those two together and then run it through a column that contains the enzyme or immobilized lipases, and that process of running it through the column and the contact with the enzymes they go through is the interesterification process," Tiffany explains. In this process, fatty acids will hydrolyze or cleave from the glycerol backbone and then reattach to the glycerol backbone in different positions, and that is what influences the melting behavior. "Depending on the ratio, the higher the amount of fully hydrogenated soybean oil that you use in the blend," he continues, "typically the solid-fat content or higher melting point you'll achieve through the enzymatic process." Less hydrogenated oil has an opposite effect. "Say you have a 65:35 blend that, before interesterification, has a melting point of 140?F and a very flat, high solid fat content (SFC) curve," Tiffany adds. "After the interesterification process, you'll lower the melting point to something similar to all purpose shortening, 118?F to 124?F melt and the SFC will be a little sharper. It will behave more similarly to partially hydrogenated soybean oil." Depending upon the ratios of soybean oil and fully hydrogenated soybean oils, custom shortenings can be created. The SFC measures the amount of solid fat at 50?F, 70?F, 80?F, 92?F and 104?F. "At body temperature, between 93?F and 104?F, in certain applications you want low solids so that you don't get that waxy mouthfeel," Tiffany says. "In other applications, you want a certain degree of flatness for bakery applications that need that plasticity. That solid-fat content helps make a pliable dough. Today, the danish and pastry operations are typically high-speed and extruded." The process extrudes shortenings and margarines into layers of dough, so the fat needs a certain degree of plasticity and workability to function in that application. Yeast-raised rolls is an application where interesterified shortenings work well. "Those types of breads typically use highly emulsified shortening," Tiffany notes. "You could use an interesterified shortening that contains an emulsifier." Likewise, butter-cream-icing shortenings can be created through interesterification, he says, as long as they have the proper solid-fat content and the right ratio of emulsifiers. Those factors, along with the air incorporation, deliver the spreadability commonly associated with icings. What is unique about interesterified shortenings, as compared to partially hydrogenated shortenings, is that the triglycerides formed are actually found in nature. The shortenings are based on stearic acid and mono- and polyunsaturated fatty acids, so it gives a full range of triglycerides that are similar to those found in cocoa-butter, palm oil and animal fat. "There wouldn't be anything that would be alarming," Tiffany says. "You're not creating a trans fat. The solid-fat systems that we're producing still have a very good balance of fatty acids. Since soybean oil has a certain ratio of polyunsaturated fatty acids, we're introducing the omega-3 and omega-6 polyunsaturated fatty acids, whereas in the past they weren't present in solid-fat shortening in partial hydrogenation. That source of polyunsaturated fatty acid is important in the diet, as well as the type of saturated that we're replacing the trans with, stearic acid, given the fully hydrogenated soybean oil is approximately 90% stearic acid. From a big-picture perspective, we feel that the low trans alternatives, the enzyme interesterification, has a well rounded profile." Food processors utilizing enzymatically interesterified products are labeling them as soybean oil, hydrogenated soybean oil. That might change. "Our regulatory group has drafted a letter and sent that to the FDA asking that we could potentially call these interesterified products different names, and the FDA did send an opinion letter back to us indicating that we could label those interesterified soybean oil," Tiffany says. Two glycerols are better for one From a health perspective, this DAG-rich oil has been shown to reduce body-fat mass and weight, and aid in maintenance. Additionally, blood lipids, particularly fasting triglycerides, are lowered. The nutritional profile of the oil, which is similar to that of conventional vegetable oil, has 120 calories per tablespoon. Vitamin E is added as an antioxidant. According to Japan's Ministry of Health Labor and Welfare, Tokyo, this product is labeled as a "Food for Specified Health Use." In Japan, formulators add DAG oil to a variety of food products, including salad dressings, margarine, canned tuna and mayonnaise. Similar opportunities exist in America. The product is heavily marketed and commercially available on the retail level, and as consumers become aware of its healthful properties, they might seek other foods containing this ingredient, such as baked goods. Tropical solutions Baked goods generally require a solid fat. "In that case, what we believe is the best solution is palm oil," McNeill says. Palm oil is naturally semisolid, making its texture ideally suited for baked goods. "It's reasonably high in saturates, but also high in the healthy oleic acid that's found in olive oil," he explains. "The saturates are called palmitic acid. That is very similar to the kind of fat you find in milkfat. Human milkfat is quite similar in composition, too." Butter was successfully used for centuries in baked goods. "It worked so well because the palmitic acid forms very small, stable crystals," says McNeil. "That's really the key to good baked goods; small crystals give a very smooth texture and they also are able to entrap small air bubbles." Blending fat with flour and sugar incorporates air into the product. Baked goods, even those that aren't highly aerated like cakes, have a little bit of air that gives them a light texture rather than a dense and chewy one. "Palm oil, having the same crystal structure that you get in butter, is ideal for baking," he says. "Europe has adopted palm oil as one of the solutions, especially in baking. Their imports of palm oil have increased from about 0.5 billion up to about 6 billion pounds in the last 10 years." Part of this increase is due to trans fat replacement. Additionally, palm is very versatile; processors can make many different kinds of products from it: "Hard, medium, soft and liquid without using any kind of chemical processing," McNeill says. Oil processors use a process called fractionation where they melt the oil and cool it slowly. Large fat crystals form suspended in a liquid oil. "You filter off that and then you've got two fractions," he continues. "One of them is a liquid at room temperature, and the other is a hard solid. These can be blended back together to give you any kind of consistency that's needed in the baked-good industry. For every type of hydrogenated fat that's out there, you can match that with a different blend of palm fractions and get about the same functionality and shelf life. As far as I'm concerned, palm oil is the best solution." In choosing trans alternatives, cost is certainly is a factor. "Palm oil is about cost-neutral to hydrogenated soybean oil. The prices track each other very closely because global production of palm oil is almost equal to the global production of soybean oil. I think, right now, palm oil accounts for about 25% of the world production of edible oils and soybean oil is about 30%," McNeill says. "The two of those, partially hydrogenated soybean oil and palm, are fully interchangeable in applications so the prices track each other very closely. Butter, on the other hand, is very highly priced at the moment. It has been traditionally. Otherwise, you could use butter. The saturated fat of butter is a bit higher than palm oil. It runs 65%. Palm oil typically comes in about 50%." Palm oil is used widely throughout the world in frying. "In Asia, they prefer palm oil," McNeill says. "Every frying oil or fat has its own unique taste. They use palm oil and that's the preferred oil, although it is interchangeable with hydrogenated soy." Europeans used it as a frying oil, as well as in baked goods. Palm oil is naturally stable, which is critical for frying oil, "especially when you're using a foodservice-type frying situation where the fryer is open to the air and, therefore, the oxygen in the air can readily access the hot oil," he says. "The hotter the oil, the quicker it goes off. You don't have to hydrogenate palm oil, and it's equivalent in stability and frying to a partially hydrogenated soy. Now the thing about palm oil is that you have liquid palm oil as well due to this fractionation process. Not only do you have solids that are great in baking, but then you fractionate so you get a liquid as well. That fries great, just like any other frying oil." Palm oil has been used in confectionary for perhaps 100 years, according to McNeill. "Cocoa-butter is the main fat component in chocolate," he says. "Palm oil fractions are very similar." For quite a long time though, companies sought out cocoa-butter replacers based on partially hydrogenated oils such as soy or cottonseed. Cocoa-butter substitutes, often based on palm, are gaining popularity. "Special kinds of palm fractions have been used in cocoa-butter substitutes, especially in Europe, for many decades," McNeill says. "You take a fraction of palm oil and fractionate it again. That double fraction is very similar in melting properties and texture to cocoa-butter. It's not usually used on its own. It's blended with other fractions from other sources, but basically it's almost used in a major component and exact match for cocoa-butter." This type of product is widely used in Europe. Regulations there allow the blending of about 5% of these fractions with real cocoa-butter in products called "chocolate." Loders Crocklaan has introduced a range of low-cost versions of these in the United States. However, "You can't call it chocolate. The texture then is not exactly the same, but less brittle," McNeill notes. These can be used to develop toppings for donuts and snack cakes, which traditionally have been based on partially hydrogenated fats. "We can fractionate a blend to match that with no trans whatsoever," he states. The beauty of palm oil, McNeill feels, is that it is completely natural. "There's no potential for unforeseen events," he says. "In the case of palmitic acid, it is the main saturated fat in humans or animals today. There aren't going to be any nasty surprises around the corner." Healthy considerations Wainwright agrees. "There is a lot more learning to occur, both on the product-development side of things as well as on the nutritional side of things." He cautions that from a process-development and ingredient-development perspective that product developers should take care that they don't outpace science relative to nutrition metabolism. Otherwise, developers might come up with other options that at least, given what they know about nutrition today, appear to be good options but then discover they might not necessarily be the best options as developers look more into how trans fats impact the overall nutrition picture. Yet Wainwright doesn't foresee the end of hydrogenation. "There's going to be some sort of a role for hydrogenated and partially hydrogenated fats to play," he says. It comes down to the options developed to position against hydrogenated products, from a product-performance perspective and also from a health-and-wellness perspective. "That certainly has not played itself out yet," he says. While the new era of low- and no- trans products is young, there are clearly positive trends in development. Francis observes, "We're developing a whole generation of what will be healthier oils, typically a little bit higher in linoleic or monounsaturated fat and lower in linolenic or the ones that are unstable. That's really the good that's coming out of all this work to eliminate trans fat."
Cindy Hazen, a 20-year veteran of the food industry, is a freelance writer based in Memphis, TN. She can be reached at cindyhazen@cs.com .
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Food Product Design: Health/Nutrition - August 2005 - Trans-Formulation Alternatives
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