Give credit — or blame, if you like — to scientists from the Harvard School of Public Health for all the work bakers and their suppliers must now do to replace shortenings containing partially hydrogenated oils (PHOs).

Revocation of the generally recognized as safe (GRAS) status of PHOs by the Food and Drug Administration (FDA) in June 2015 is largely due to that work. In the 1990s, these researchers initially sounded the alarm about trans fatty acids and their degenerative impact on the cardiovascular system.

Revoked, not banned

Seeking to better stabilize vegetable oils, which were widely available, oil chemists experimented with hydrogenation to convert carbon double bonds present in unsaturated fatty acids. They succeeded wildly and set the stage for vegetable oils to replace animal fats in processed foods.

This change to PHOs was seen first as beneficial and healthy, but a closer look at the nutritional consequences proved everyone wrong. Hydrogenation flips the isomeric form of some fatty acids from their natural cis configuration to trans. In the past, humans consumed trans fats only when eating animal fats. Today, PHOs are the leading source of trans fatty acids in the human diet and in bakery shortenings.

Removal of their GRAS status does not ban outright the use of PHOs in foods. Instead, by 2018, food manufacturers who want to continue to formulate with these fats must now submit a food additive petition to FDA detailing their safe use.

Most food companies won’t go through this lengthy and costly process; however, the Grocery Manufacturers Association (GMA) has submitted a petition that is currently being reviewed by FDA. GMA emphasized to the food industry that FDA’s reversal of GRAS status does not mean trans fats have been banned, as has been erroneously reported.

Mandatory labeling of trans fats on the Nutrition Facts Panel has been in place since 2006 and is not going away. Therefore, any approved additives that contribute trans fats must still be identified if present at greater than 0.5 g per serving.

FDA once estimated that almost all crackers, about 95% of prepared cookies and 80% of frozen breakfast products contain trans fat. The addition of this one line of information on the Nutrition Facts Panel fueled a major shift in bakery shortenings intended for use by retail and wholesale bakers.

In general, baked goods are one of the toughest applications to reformulate because the fat performs structuring, flavoring and texturizing roles. Breads and rolls made the easiest conversion to liquid oils, and some cakes were readily reformulated with oils. With cakes, however, there are challenges for high-ratio formulas, where sugar and shortening must be creamed to give the finished products the right texture. Pie crusts are quite difficult to make without the solid fats contributed by shortenings. The roll-in fats and margarines for croissants and Danish are also hard to replace.

Understanding shortenings

Bakery shortenings typically consist of low-melting-point liquid oils and higher-melting-point solid fats. They are compound products often containing many types of fats and oils, with the solid fats forming a matrix around the liquid oils. This yields a semi-solid fat that is soft, smooth and spreadable with optimum lubricity and desirable crystalline structure.

“Bakery shortenings must have appropriate plasticity to allow them to be creamed into a dough or batter but also lend specific characteristics while being deposited, baked and packaged,” said Lynne Morehart, senior principal scientist, oils and shortenings, Cargill, Plymouth, MN. “If used in cakes, frostings or yeast-raised products, they will typically contain emulsifiers, which will aid in aeration and moisture retention.”

Bakery shortenings require some level of solids for performance. Their unique composition contributes many desirable functions to baked goods, such as aeration, crumb softness and structure, dough lubricity, emulsification, extended shelf life and overall improved palatability.

Long ago, many of these functions were achieved simply through the use of solid fats sourced from animals, such as butter (milk fat), lard (pork fat) and tallow (beef fat). However, when the health community raised concerns about saturated animal fats, suppliers responded with vegetable-based choices.

“The introduction of hydrogenation allowed use of domestic vegetable oils, such as cottonseed, corn and soybean, at low cost in bakery shortenings,” said Bob Johnson, director of oils, R&D, Bunge North America, St. Louis. “When an oil is hydrogenated, its fatty acids are converted from polyunsaturates to monounsaturates to saturates. Directionally, this can be seen as a hardening of the oil or an increase in its solids and melt point.”

This is where the distinction between partially hydrogenated and fully hydrogenated must be made. The difference between the two has enabled much innovation in the category. 

“When an oil is partially hydrogenated, some of the monounsaturated fatty acids exist as the trans isomer. This is the concern with PHOs,” Mr. Johnson said. “But when that oil is fully hydrogenated, those monounsaturates are converted to saturates, which do not have any trans present.” These saturates provide solids that can be used in structuring bakery shortenings.

Broad menu of choices

With the intense scrutiny given recently to reducing and eliminating trans fats and PHOS, ingredient suppliers have expanded their product offerings considerably. And some are exploring new sources.

Bunge offers a broad range of non-PHO solutions. “There’s an ingredient for every bakery application,” Mr. Johnson said. “For example, for our cracker customers, we offer high-stability soy and canola oils. We have also developed a process that allows us to enzymatically structure bakery shortening using only domestically grown soybeans for the shortest possible distance from farm to bakery.”

The company formed a joint venture with Solazyme, South San Francisco, CA, to launch micro-algae-based fats and oils early this year. The line includes high-stability algae oils and an algae butter-type structuring fat. The latter has a composition and functionality for superior performance in baked goods, including applications such as icing and frosting, as well as croissants, which require hard fats that are solid at room temperature, yet still have melting properties.

“In all, we have non-PHO fats that range from 17 to 65% saturated fatty acids,” Mr. Johnson said.

Cargill has multiple products available as PHO-free shortenings. “There are palm-based shortenings, interesterified shortenings, palm/liquid oil blends and liquid oil/FHO blends,” Ms. Morehart said. “We work with our customers to understand their applications, as well as labeling and nutritional parameters to help them determine the shortening to meet their needs. As we dig deep to understand what our customers need to achieve, they often discover attributes along the way that take them in a different direction than their initial thought.”

At AAK, blending of various oil stocks increased the company’s range. “Our PHO-free shortenings are produced from different components,” said Monica Zelaya-Brown, customer innovation manager, AAK USA Inc., Edison NJ. “We can use fractions or interesterified blends of palm and palm kernel oils, oleins and stearins; soft oils such as canola or high oleic sunflower/canola oils; and soybean oil, with the option to interesterify it for desired functionality.”

Suppliers who blend varied fats pride themselves on the ability to deliver ingredients with multiple functions. Ms. Zelaya-Brown described a recent project. “A customer wanted to penetrate a very competitive market segment and did not have sufficient R&D resources to dedicate to the product development of a high-quality, bake-stable cookie filling,” she said. “AAK had the capability to support this project by developing a two-pronged approach for the cookie dough itself, as well as the filling. The end result was a cookie with a better texture for an extended period of time.”  

FDA’s revocation of GRAS status for PHOs is something bakery shortening suppliers have anticipated for nearly a decade, if not longer. The fats and oils industry has responded effectively to the evolving needs of the baking community in the post-PHO era.

“Solutions are available for all applications,” Mr. Johnson concluded. “The challenge for many is in balancing the cost of the solutions with the specific attributes that are needed for their products.”