Time for an Oil Change?

From alpha to omega, todays fats and oils are all about the fatty acids: their bonds, configuration and arrangement. Understanding these enables product designers to change one fat or oil for another when pursuing a more-healthful lipid profile.

Knowledge of the properties of fats and oils provides a clearer understanding of their functional behavior in foods, said Gloria Cagampang, fellow, Kellogg Co., Battle Creek, MI, at the 5th Global Oils and Fats Business Forum of the American Palm Oil Council, held Sept. 2007 in Las Vegas. It is a tool in understanding the basics of their stability that affects the quality of the finished foods.

It provides the background of how we can accomplish most effectively the formation of better trans-fat-free solutions for the foods we make, Cagampang continued. The bottom line is that there are no one-size-fits-all solutions when trying to improve the fat profile on a Nutrition Facts. It is essential to balance the fats functionality and availability with its stability in the application.

Fatty acids define the characteristics of fat and oil ingredients. If the majority of fatty acids are saturated, then the triacylglycerol is solid at room temperature. As unsaturation increases, the triacylglycerol becomes more liquid. The greater the unsaturation, the less stable the triacylglycerol is to oxidation.

Seeking stability is how trans fatty acids came to fruition. Historically, high-saturate fats were used in formulations when the functionality of a solid fat and its corresponding stability was required, particularly in baking and frying applications.

When nutritional scientists learned that saturated fatty acids clogged arteries and increased consumers risk of heart disease, lipid chemists turned to hydrogenation. This process improved the stability of unsaturated fatty acids by reducing the number of double bonds and reconfiguring (from cis to trans) the position of the hydrogen molecules on the remaining double bonds.

For some time, to improve the lipid profile of a manufactured food, the solution seemed simple: Replace saturates with partially hydrogenated fats. As is often the case with simple solutions, this one soon experienced some snags.

Scientists said hydrogenations trans configuration yielded a fatty acid even more detrimental to the cardiovascular system. This message made its way to consumers, regulatory agencies and food manufacturers.

Fatty acid profiles

Todays fatty acid messages are clear. Eliminate trans. Reduce saturates. And while youre doing that, increase omega-3s. To better understand todays fat and oil ingredient options, it is necessary to review some details about the key dietary unsaturated fatty acids.

The no-double-bond configuration of saturated fatty acids produces a straight chain molecule. When two or more saturated fatty acids are present on a triacylglycerol, this configuration packs the fatty acids tightly, resulting in a solid, stable fat with a high melting point.

Oleic acid (OA) is the most-common monounsaturated fatty acid among dietary lipids. It contains 18 carbons and has a single double bond at the ninth carbon from the terminal end of the chain. This configuration has some referring to monounsaturates as omega-9s.

Because this fatty acid has only a single double bond, OA somewhat resembles a saturated fatty acid. Oleic acid is a rather stable, almost straight fatty acid that has a higher melting point than PUFAs, says Tom Tiffany, manager of food oils applications and technical services in research and development, ADM, Decatur, IL. With PUFAs, increased unsaturation decreases stability and solidity. The fatty-acid chain has more kinks and a lower melting point than OA. In efforts to eliminate trans and keep saturates low, the industry is transitioning to higher-OA oils. They offer more oxidative stability.

Unfortunately, this means reducing the concentration of the essential omega 3 fatty acid alpha-linolenic acid (ALA), an 18-carbon chain with three double bonds that is extremely prone to oxidation. Linoleic acid (LA), an omega-6 made of 18 carbons and two double bonds, is a bit more stable than ALA, but not as stable as OA.

Transitioning to trans-free

Manufacturers can take a variety of approaches to report zero grams trans fatty acids on the Nutrition Facts, but almost all have some drawback, ranging from ingredient cost to shorter product shelf life to increasing saturated-fatty-acid content. (Foods can still contain some trans fatty acids, even when the Nutrition Facts reports zero, because FDA requires reporting on a per-serving basis. Thus, if a food has less than 0.5 grams of trans fatty acids per serving, the Nutrition Facts states zero.) When it comes to price and availability, few domestic oils can compete with soybean oil. But, in its natural state, soybean oil is not very stable. It is about 8% ALA, 54% LA, 23% OA and 15% saturated fatty acids. Thus, for a long time, its hydrogenated form was the one used in most industrial and foodservice applications.

Other domestic oils are naturally more stable than regular soybean oil and, depending on the application, some food manufacturers can successfully use them. For example, cottonseed oil contains only a trace of ALA. Further, it is about 19% OA, 54% LA and 27% saturated fatty acids. This profile results in a fairly stable fat that does not require hydrogenation for stability in many industrial and foodservice uses.

In its native state, corn oil is also more stable than soybean oil, as corn oil contains only a trace of ALA and is higher in OA (27%), slightly higher in LA (57%) and slightly lower in saturated fatty acids (13%).

In 2007, FDA authorized a rather uninspiring qualified health claim for corn oil: Very limited and preliminary scientific evidence suggests that eating about 1 tablespoon (16 grams) of corn oil daily may reduce the risk of heart disease due to the unsaturated fat content in corn oil. FDA concludes that there is little scientific evidence supporting this claim. To achieve this possible benefit, corn oil is to replace a similar amount of saturated fat and not increase the total number of calories you eat in a day. One serving of this product contains [x] grams of corn oil. The wordiness and the ambiguity will likely lead few, if any, food marketers to use this claim on product packages, but in reality, it is a positive.

Most of the buzz regarding domestic oils is surrounding new oils with increased OA and decreased ALA as a result of conventional cross-breeding technologies. For example, canola oil now comes in two types: commodity (or classic) and high-oleic (or high-stability), which is only available for industrial and foodservice operations. Both have the same low level of saturated fatty acids (7%). However, as the name suggests, the conventionally bred high-oleic canola oil contains more OA and fewer PUFAs.

Canola oil, too, has a qualified health claimmore consumer friendly than corn oils. Authorized in 2006, the claim reads: Limited and not conclusive scientific evidence suggests that eating about 1.5 tablespoons (19 grams) of canola oil daily may reduce the risk of coronary heart disease due to the unsaturated fat content in canola oil. To achieve this possible benefit, canola oil is to replace a similar amount of saturated fat and not increase the total number of calories you eat in a day. One serving of this product contains [x] grams of canola oil.

Of all commonly used oils, classic canola has the lowest saturated-fatty-acid content. The high-stability variety has a minimum of 65% OA, rendering it particularly well suited to foodservice, as it offers extended fry life (300-plus fryings), higher heat tolerance and cost efficiencies.

Similar breeding efforts have taken place in the sun- flower and safflower industries. There are two types of saf- flower oil: classic, which is high in PUFAs, and oleic, which is high in OA. The latter has been used successfully in many baking and frying applications.

NuSun® is a mid-oleic sunflower oil with lower saturates (less than 10%) than classic sunflower oil and higher oleic levels (55% to 75%), with the remainder being LA (15% to 35%). NuSun, at an average of 25% LA, has been identified as possessing the optimum amount of LA to develop a desirable fried-food flavor in most frying applications.

It also makes sense to apply such cross-breeding technology to the most readily available U.S. oil crop: soybean. In Dec. 2007, Asoyia LLC, Iowa City, IA, rolled out Mid Oleic Ultra Low Lin Soybean Oil. We started with Asoyias first-generation Ultra Low Lin Soybean Oil, which contains no trans fatty acids, is low in saturated fatty acids (14%) and contains less than 1% TLA, says Terri Volpe, technical advisor, Asoyia. Advanced breeding enabled our farmers to increase the less-stable linoleic content while decreasing the less-stable linoleic content. The resulting oil is more healthful and just as stable and functinoally better than some of the not-so-good-for-you fats in the American marketplace.

Offshore oil options

Obtaining edible oils from abroad is another option. Without a doubt, the most-healthful imported oil is olive. With three quarters of its fatty acids being OA, olive oil is very stable. It also contains about 15% saturated fatty acids, 9% LA and a mere 1% ALA.

Olive oils drawback for industrial and foodservice applications is price. For most applications, it is just too expensive. Some upscale products might be able to command a premium to offset the costs associated with olive oil.

Depending on the application, product designers can choose from three primary grades: extra virgin, pure and grade B. Extra virgin is first-pressed oil, which is only filtered, not processed or refined. It has a dark-green to golden color, and smells and tastes like olives. Pure olive oil is pressed and refined, resulting in a lighter color and flavor than extra-virgin oil. It is golden-yellow with a green undertone. Grade B, also called pomace olive oil, is chemically extracted and fully refined. This has very little olive flavor or smell, yet still provides the healthy benefits of olive oil.

The buzz in offshore edible oils surrounds the palm fruit, which yields two very different types of oil. Palm oil comes from the fruits flesh, while palm kernel oil comes from the fruits core.

Palm kernel oil resembles coconut oil, as both are very high in lauric acid, a 12-carbon-long saturated fatty acid. Palm kernel oil has a minimum of 75% saturated fatty acids. Palm oil, on the other hand, is only about half saturated fatty acids. It is also largely available; in the world market it is the No. 1 traded edible oil.

Palm oil contains no trans fatty acids and is high in monounsaturated fatty acids (about 40% OA), says Marjorie Gilbert, food ingredients director, AarhusKarlshamn USA, Inc., Port Newark, NJ. The remaining 10% is LA, as palm oil contains only a trace of ALA. The saturated fatty acids in palm oil are almost all palmitic acid, a 16-carbon chain that naturally crystallizes into beta-prime crystals. These crystals are small in size, so they impart a smooth texture to the fat while keeping the fat stable, yet soft in texture.

Palm oil easily fractionates to yield functional components, says Gilbert. It is a natural source of solid fat, making it a logical alternative to many of the hydrogenated fats in the marketplace. Palm oil can be separated into fractions known as stearins and oleins. Palm olein is the liquid, more-unsaturated fraction. It consists of a homogeneous mixture of triacylglycerols and has properties and uses that differ from those of the original oil. Palm stearin is the more-saturated and more-solid fraction of palm oil. Its fatty-acid composition is variable, depending on the process employed to isolate it, ranging from 67% to 88% for saturated fatty acids, 16% to 37% for OA, and 3% to 10% for PUFAs. Palm stearin is used in products that require a higher degree of saturation, such as margarines and shortenings.

To report zero trans fats on product labels and keep saturated fatty acids low, many food manufacturers are turning to the blending of fats and oils, says Gilbert. Blends of liquid oil with highly functional solid components derived from palm and palm kernel oils yield highly functional shortenings that are both trans-free and have reduced saturates.

Gerald McNeill, director of research and development, Loders Croklaan, Channahon, IL, adds: Palm oil is often termed as a saturated fat in the media; however, it is a balanced fat and contains an equal proportion of unsaturated and saturated fatty acids. Emerging research over the past 10 years shows that saturated fatty acids are actually neutral in the body. Contrary to the theory established in the 1970s, saturated fatty acids appear to have little or no effect on the clogging of arteries. Looking forward, we are going to see a change in the way people think about fats and fatty acids, says Mc- Neill. Science is constantly evolving, and we are gradually improving our understanding about the components of food and food ingredients.

Indeed, lipid research is ongoing, with advancement in interesterification (rearrangement of the three fatty acids on the glycerol backbone to achieve improved stability), as well as fatty-acid fortification (adding back omega-3s after the removal or reduction of the essential fatty acid ALA).

Omega-3 overview

Omega-3s are powerhouse fatty acids that have been shown to positively impact cognitive development and function, cardiovascular health and more. There are basically three omega-3s available as an ingredient: ALA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Plant-derived ALA is an essential fatty acid and can be converted in the human body to DHA and EPA. However, the efficiency of the conversion process from ALA to DHA and EPA varies by consumer, diet and other factors.

Theres a North American oil flax seedthat is seldom used in baking and frying applications because of its very high ALA (57%) content. Extremely prone to oxidation, when flax seed oil is used as an ingredient, it is usually in small doses and as an omega- 3 fortifier. Rather than using flax seed oil, food formulators often turn to the array of flax seed ingredients in the marketplace that have been specially processed to retard oxidation and yet still add a noteworthy amount of ALA to the formula.

Other food designers opt to add DHA and EPA ingredients to food formulations, since they have an associated qualified health claim that reads: Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease. One serving of [name of food] provides [x] grams of EPA and DHA omega-3 fatty acids.

Regardless if you add ALA, DHA or EPA, labeling laws must still be followed, as FDA reminded marketers at the beginning of the year. According to a proposed rule, FDA will allow only products using ALA to make nutrient content claims, such as good source of ALA. FDA based the proposed change on information provided by the National Academy of Sciences Institute for Medicine, which has determined recommended intake levels for ALA but not for DHA or EPA.

Thus, processors will not be allowed to use label claims such as excellent source of omega-3 EPA and DHA. The proposed rule would not affect the ability of companies to use the omega-3 qualified health claim or to make truthful statements about omega-3 content, such as 32 mg of DHA omega-3 per serving. Look to the March issue of Food Product Design for an update on omega-3 fatty acids.

In addition to working out the labeling jargon, there are noteworthy advancements being made in the area of preservation through the addition of natural antioxidants such as those found in rosemary extract and select vitamins. As always, in the end, the product must meet consumers expectations.

Our view of healthful fats and oils has evolved and will continue to evolve, concludes Gilbert. A fat with a healthy profile is not sufficient. It must also provide the functionality demanded by the specific application.

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 about product development and marketing for 13 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].