Icings and frostings may rely on shortenings for such traits as shape, stability and aeration. Some shortenings, in turn, still rely on partially hydrogenated vegetable oils. That reliance, however, soon may end.

The Food and Drug Administration in the Federal Register of Nov. 8, 2013, said it tentatively had determined partially hydrogenated oils (PHOs), a primary dietary source of industrially produced trans fat, are not generally recognized as safe (GRAS) for any use in food. If this proposed rule is finalized, food manufacturers no longer would be permitted to sell PHOs, either directly or as an ingredient in products, without prior F.D.A. approval for use as a food additive.

Finding PHO alternatives is more difficult in some applications.

“The majority of food manufacturers made changes in the last few years and removed partially hydrogenated oils/shortenings from their products,” said Lynne Morehart, technical services manager for Cargill in Plymouth, Minn. “For those who were still using partially hydrogenated oils/shortenings, the recent proposed rule triggered them to quickly look for solutions. In most cases, food manufacturers who were still using the products did so because the applications were tough to reproduce functionally, economically or nutritionally.”

Icings and frostings are examples.

“Icings and frostings are fairly simple food applications containing just a few ingredients, primarily sugar, shortening, water and stabilizers/emulsifiers,” said Jim Robertson, product category manager, emulsifiers, for Corbion Caravan, Lenexa, Kas. “However, the shortening is one of the most critical ingredients in the formulation. Shortenings are responsible for the consistency and spread-ability associated with an icing/frosting, and they also play a critical role in the aeration/whipping properties associated with an icing when combined with the proper emulsifier system.

“Non-PHO shortenings typically have different textural/melting properties than partially hydrogenated shortenings that translate into changes in spread-ability and stability that can be challenging to overcome.”

Corbion Caravan manufactures a line of specialty emulsifiers under the Trancendim name. The emulsifiers may be melted into a mixture of oils to provide the textural properties associated with a partially hydrogenated shortening at moderate saturated fat levels, without the presence of trans fat, he said.

“Oils used in shortenings for icings/frostings are custom manufactured to the physical and chemical characteristics that are required for the said end-uses,” said Tiger Tangavelu of Global Agri-trade Corp., Long Beach, Calif. “Partial hydrogenation is a relatively inexpensive process used to achieve that. In looking for alternatives that work, the food manufacturers’ wish-list often includes avoiding another manufactured fat and inexpensive.”

No single drop-in product may work for non-PHO shortenings, said Rick Cummisford, quality director, Columbus Vegetable Oils, Des Plaines, Ill.

“So (companies) have to reformulate,” he said. “They’ve got to reprocess, moderate the process, whether it’s blending times or temperatures.”

Back in 2004 Columbus Vegetable Oils had maybe 12 shortening products, he said. The number has grown since then.

“We’ve got over 70 products,” he said. “We always have to offer multiple potential solutions and then slowly work toward the finish product results that (Columbus Vegetable Oils’ customers) are looking for.”

Palm oil, including in oil blends, might be a solution.

Partially hydrogenated vegetable oils deliver such functionalities as melting point, crystal habit and extended shelf life, said Jeffrey B. Fine vice-president of customer innovation for AarhusKarlshamn USA.

“Creating PHVO-free fat systems that deliver all of these properties is a challenge,” he said. “Palm-based fats are capable of delivering many of the same functionalities without hydrogenation and make excellent shortenings and icings. Other solutions exist as well.”

There are already shortenings for icings and frostings that are palm-based and meet many end-users’ expectations, Dr. Tangavelu said.

“However, palm oil being a natural ingredient is at times not a drop-in alternative for PHO that is highly custom manufactured for some types of shortening for icing/frostings, and, in some end-use applications, palm oil-based shortening for icings/frostings falls short of bakers’ expectation that includes for icings/frostings where whiteness is absolutely required,” Dr. Tangavelu said. “The so-called shortcomings of palm oil-based shortening for icings/frostings in some end-use applications are mitigated by using new fractions of palm oils and/or with blends containing soft oils. The expectation of whiteness is readily met using non-commodity low color palm oil in the formulation.”

Ms. Morehart said, “Icings/frostings require solid fats in order to maintain the appropriate structure of the frosting, allow them to decorate as desired and to ‘keep the frosting’ on the cake. These are requirements that liquid oils cannot provide. Palm oil can often be too brittle or exhibits a post-crystallization hardening that alters the finished product negatively during its shelf life. Blends of liquid oils, palm fractions and/or fully hydrogenated shortenings typically take more work to achieve the desired function.”

She said the desired function may be achieved through several strategies: mixing/incorporation changes, adding ingredients that help with modifying structure, manufacturing changes or a combination of all the above, she said.

The F.D.A. has yet to rule on the ban on partially hydrogenated oils.

“People are trying to predict what the F.D.A. is going to do and when it’s going to happen,” Mr. Cummisford said. “Many (companies) are responding and acting now.”

Mr. Fine said he believed removing PHOs from applications with shortenings is possible.

“The impact of the recent F.D.A. announcement has been manageable since AAK has been developing and offering solutions since 2006 when the labeling of trans fatty acids became mandatory,” he said. “A large amount of technical ground has already been covered, and AAK offers a complete line of PHVO-free bakery and confectionery fats. We are well poised to meet the needs of our customers well in advance of the final F.D.A. ruling, whatever it may be.”