Phasing out PHOs
June 28, 2016
by Laurie Gorton
Enzymatic interesterification randomizes and reassembles the fatty acids comprising triglycerides, raising their hard fat properties without producing trans fats.
Less than two years from now, the regulatory hammer comes down on some of the baker’s most reliable ingredients: shortenings made with partially hydrogenated oils (PHOs). The Food and Drug Administration (FDA) announced withdrawal of the Generally Recognized As Safe (GRAS) status of PHOs effective June 18, 2018. The agency acted to eliminate from the American diet a known heart health risk, the trans fats generated during hydrogenation.
That action changes nearly everything about bakery shortenings. All choices are up for grabs, from base oils and hard fats to processing methods and product labeling.
The formulator’s decision used to be simple: just pick an all-purpose shortening. But then trans fats came under scrutiny, requiring labeling of their presence in foods, starting Jan. 1, 2006. Now, with the pending disappearance of PHOs, bakers need to know a lot more about the content and manufacture of their shortenings. So do snack food makers.
But don’t dream of returning to the single all-purpose approach. “It’s important to remember that an all-purpose shortening was never truly ‘all purpose,’ ” said Lynne Morehart, oils and shortenings senior principal scientist, Cargill. “It would make great cookies and potentially a good pie, but that was about it. More specialized shortenings have always been used for other bakery applications.”
Shortening technology has moved on, but the resulting non-PHO shortenings present hurdles, too.
Monica Zelaya-Brown, customer innovation manager, AAK USA, explained, “The biggest challenge in working with non-PHOs versus PHOs is that the formulator can sacrifice their range of functionality and process tolerance if the right replacement fat system is not used.”
The migration is already well underway. In the past decade, Columbus Vegetable Oils has seen a shift by at least 80% of its PHO users to non-trans alternatives, estimated Rick Cummisford, director of quality.
By blending base oils with a source of solid fats, shortenings can be created to give cookies the creaming characteristics required for best batter performance.
Nature of the problem
Making the switch won’t be easy. “The essence of the problem is that baking is a complex food system,” said Dave Dzisiak, commercial lead, grains and oils, Dow AgroSciences. “It encompasses different goods, with different textures and different shortening needs. These change from bread to crackers to croissants to frozen doughs.
Bakery shortenings require both solid and liquid fats, balanced in different proportions depending on application. The hydrogenation process could dial-in that performance, but non-PHO processing techniques depend on other means, such as blending, interesterification and emulsification to achieve the needed functionality.
“When developing trans-fat-free bakery shortenings, we need to be aware that solid content is important to deliver functionality,” Ms. Zelaya-Brown said. “In the past, mostly tropical or fully hydrogenated fats were used in the quest to build up solids. Nowadays, many solutions consider combining low-saturate liquid oils with trans-free solid stocks that give the plasticizing properties required.”
Major differences exist in composition and performance of shortenings, depending on how they are to be used. Frying and foodservice applications typically employ liquid shortenings, and bakery products benefit from textured shortenings, often called plastic shortenings.
For frying, the key factor is the life of the oil. “To this end, the starting fatty acid composition is the critical attribute,” explained Roger Daniels, vice-president, research and innovation, Stratas Foods LLC. “Oils elevated in oleic fatty acid levels typically have enhanced frying functionality due to their ability to stave off the impacts of auto-oxidation and thermal degradation reactions.”
Baking takes advantage of the shortening functions involved with product tenderness or structure. “This is principally accomplished during the mixing process when the shortening is combined with flour, sugar, water and other components,” Mr. Daniels said.
The shortening encases the flour proteins, limiting their ability to link up, thereby “shortening” the full development of the protein network. “By finding the optimum balance of shortening composition, shortening quantity in the bakery recipe and mixing and baking times, the end user is able to achieve the desired bakery products,” Mr. Daniels explained.
The shortening requirements of some products will be more difficult to manage, according to Ms. Morehart. “The tougher applications of frostings, puff pastry, Danish, pie crusts and some cookies need to have solid fat to aid in the appropriate structure of those products,” she said. “Non-PHO products tend to need more specialization for many of these more challenging applications. They also typically require changes to manufacturing parameters, ingredients, sequence of ingredient addition or packaging materials.”
High oleic canola oil has the stability to stave off auto-oxidation and thermal degradation.
Reshuffling the deck
With hydrogenation out of the picture, the characteristics of base oils take on more importance. “Among other factors, the choice of base oils can impact flavors, texture, color and stability of end products and can be affected by processing parameters such as temperature and so forth,” explained Tara Froemming, marketing coordinator, Healthy Food Ingredients.
Performance attributes of base oils such as smoke point, melting point and firmness provide building blocks, observed Brian Armstrong, senior director of innovation and R&D, Bunge North America.
Nature endows plant oils with widely varying fatty acid compositions. They come in conventional, non-GMO and organic styles, too.
Thus, shortening producers tap many approved oil suppliers. “Altogether, we use more than 250 types of oils for our products,” Mr. Cummisford said.
“The base oil for the shortening is key in getting the right texture, melt profile and physical properties for the finished product,” he said. “Every application, process and finished product is a little different.”
Ms. Zelaya-Brown also emphasized the role of the base oil. “Soy, canola and sunflower oils favor forming mono- and polyunsaturated moieties that, when combined with solid base stocks, deliver required plasticity for bakery applications,” she said. “Thus, they compare well with previous hydrogenated shortenings. While fatty acid composition and content provides a differentiation point, it is the fat’s contribution to solids at lower temperature, oxidative stability and bland flavor which is assessed for performance in the final application.”
Mr. Armstrong described selection of base oils for preferred performance in specific applications. “We use soybean oil as a base for one of our specialty shortenings developed for very cold pie dough,” he said. “Here, we rely on the inherent characteristics of the base oil, then apply our unique enzymatic process to deliver a domestically sourced, trans-fat-free solution without partial hydrogenation. The benefit of application-specific shortenings is that they can be more finely optimized to achieve the baker’s goals in a given formulation.”
Quest for hard fats
In bakery uses, the shortening’s solid fat content — and the melting and crystallization behavior of the solid fats — is responsible for its functionality. Such needs differ for each application. “For example,” said Tom Tiffany, senior technical sales manager, ADM Oils, “puff pastry needs more solids to help keep distinct layers of shortening between layers of dough while maintaining desirable dough handling properties along with creating the flakiness associated with pastry.”
In PHOs, trans fats contribute the majority of the solid fats. This fact causes great difficulty in development of shortenings for bakery and snack use. “The reason is that PHO was effectively not just one oil but an unlimited number of tailor-made shortenings,” said Gerald McNeill, PhD, vice-president, R&D and marketing, IOI Loders Croklaan Americas. “That gave formulators the ability to innovate multiple ways in areas such as texture, long shelf life, speed of crystallization, fast line speeds on factory lines. The list goes on.”
The question remains — how to compensate for the solids that trans provided?
One solution is to blend fully hydrogenated soybean oils into liquid oils. Another is to use palm oil and its fractions to supply hard fats to blend with liquid oils. Yet a different process employs fiber to stabilize the shortening, and another blends in starch. Vegetable waxes and emulsions also show potential.
Interesterification, a PHO-free option, rearranges the fatty acids that make up the oil’s triglycerides and, thus, changes its characteristics without generating trans fats, according to Mr. Daniels.
Mr. Dzisiak identified interesterification as a process that expands choices. “These new technologies give really good products that weren’t available before,” he said.
Palm oil, which is naturally semi-solid at room temperature, is today widely used in shortenings to achieve texturally superior products, according to Tonya Lofgren, marketing manager, Ciranda, Inc. She pointed out its growing popularity for bakery and snack applications.
Palm oil also lends itself to fractionation, a physical process that yields up to 12 different components called fractions. “Each fraction has significantly different physical properties,” Dr. McNeill explained. “They can be blended in an unlimited number of ways to almost match all of the PHOs of the past with none of the trans fat.”
Bunge opted for palm oil with its high melting point to create its line of canola-based all-purpose shortenings, Mr. Armstrong explained. “This allows the complete elimination of ‘hydrogenation’ from a label,” he said. The use of canola cuts the saturate level up to 60% compared with a palm-exclusive shortening.
In muffin and cake applications, shortening coats flour particles to yield tender crumb but supportive structure.
Blending oils, fats
Have no doubt, there is a complex set of challenges involved. “That’s where blending helps,” said Mr. Dzisiak. “You can take a hard stock, for example, a palm oil, and blend it with the new-generation, high-stability oils like canola. Thus, saturated fats are reduced, yet you have the shelf life needed. All this takes extra work and can result in a bit of extra cost, but it delivers a cleaner ‘read’ on finished product labels.”
Mr. Armstrong agreed, “Blends are a great way to achieve desirable performance in multiple areas, like a PHO-free shortening that’s also lower in saturates.”
Shortening processors used blending during the PHO era to target a varying degree of solid fat contents and melting points, Mr. Tiffany explained. “The same concept is applied today for non-PHO options,” he said. “Liquid oils can be blended with palm and palm fractions to target different melting properties, or liquid oils can be blended with fully hydrogenated oils to achieve certain functional attributes.”
When it comes to functionality, liquid oils are comparatively the same with variations occurring in flavor and shelf life stability, Ms. Morehart noted. To give them the performance of shortenings, solid fats are required.
“You must ensure that the base oil options will allow the shortening to function for the application,” she said. “For instance, a 100% palm product could be used as an all-purpose shortening in a cookie, but it may need to be creamed differently or stored differently compared with historical PHO shortenings,” Ms. Morehart said.
“The addition of a liquid oil, at determined percentages, would soften the palm and may be a friendlier choice at colder temperatures,” she continued. “The liquid oil choice would then be important in regard to the flavor stability it brings, as well as the cost. An interesterified oil could be used but may require different handling and storage temperatures to ensure that it does not get too soft for the application.”
Blends of oil and fat work for general bakery applications like cookies, tortillas and pie crusts if the components are optimized relative to the ratios of liquid to solid components and functionally crystallized to achieve the desired morphology, said Richard Galloway, consultant, Qualisoy. This approach may give melting profiles that are relatively generic even though solid materials may be higher than the PHO being replaced. This may impact the texture of the baked product and organoleptic properties of the baked product. Adjustments to the recipe or bakery process typically allow a return to PHO-like performance, he observed.
Shortening systems blended for frostings and fillings must provide enough structure to hold critical volume achieved during aeration, Ms. Zelaya-Brown noted. “If we look only at solid fractions, we may increase saturated fat to an undesired level and may not be able to offer a wide variety of melting ranges,” she said. “Therefore, we advise blending both solid fractions and soft oils to deliver on structure, as well as to keep the total saturated fats levels low.”
On the other hand, firm-to-solid fats are needed for applications such as pie crusts, which cannot use liquid oils. Instead of creaming the fat with other ingredients during mixing, it must be cut into the flour. During baking, the fat melts, and the flour forms flakes. The space left by the melted fat separates these flakes. “Liquid oils would interfere with proper mixing and would not allow for a flaky crust,” Ms. Zelaya-Brown explained, “But, palm oil at 100% is often too firm for pie crust. Often times, a blend of a liquid oil and palm oil will promote optimal mixing, forming and baking.”
Semi-solid at room temperature, palm oil supports the hard fat and texture needs of bakery shortenings.
Availability, other considerations
Even before FDA’s removal of PHOs, bakery shortenings were already changing. Ms. Lofgren observed, “The ‘blend trend’ may sometimes be less about functionality and more about finding a balance of additional factors — cost, shelf life and nutritional profile — while maintaining the texture that consumers expect.”
Ms. Froemming added, “In many ways, this blending could provide a replacement product that is a better fit for each individual product including desired nutritional profiles, oil source and/or profile — monounsaturated, polyunsaturated, saturated.”
It also helps that palm and canola are more abundant today than ever before. “The availability of new-generation oils is expanding as the number of varieties increase,” Mr. Dzisiak said. “Another factor is that the biodiesel market has matured. It competes with the food industry for supplies of these oils, and that has leveled off. It will be easier for the food industry to access these oils.”
Issues beyond functionality and flavor also factor into decisions. Mr. Cummisford noted sustainability, economics and even philosophy involving GMOs and saturated, tropical and animal fats. “Companies may have specific requirements in these regards,” he said. “For bakery products, saturated fats can be critical to performance, but palm oil is imported and may bring with it the political questions of sustainability. Different certifications are available to monitor that aspect of the supply chain.”
Bunge addressed the low-sat desire by developing custom blends with multiple raw materials. One example is a zero-trans specialty shortening blending canola, palm and soy along with phytosterol esters to deliver up to 46% reduction in saturated while retaining the sensory attributes of the finished application. Mr. Armstrong said, “This can help a baker or snack-maker better achieve nutrition claims while retaining the indulgent experience people expect from baked goods — both on the menu and at shelf.”
There’s also the language of ingredients. For example, fully hydrogenated oil contains no trans fats, but that message is hard to communicate to consumers who may only see the word “hydrogenated.” Likewise, “interesterified” can be confusing to end users.
“When going clean-label, you may not want those words on the product label,” Mr. Dzisiak said. “In reducing the number of ingredients on the panel to things people have more familiarity with, you’ll need to remove the ingredients with the more ‘chemical sounding’ names even though they are proven safe.”
On the positive side, “organic” has potential that is largely untapped. “There’s not as much demand for organic fats as there are for non-GMO,” Ms. Froemming observed. “But the organic message may not have filtered down to the processing side yet. That may change as people start to get more knowledgeable about organic. After all, organic is all non-GMO.”
Now’s the time to move baked goods and snacks out of PHOs and into new-generation fats, oils and shortenings. That June 18, 2018, deadline will be here before you know it.