Selection of alternatives for clean label fats & oils depends on several factors. They include how the manufacturer defines clean label; the desired functionality of the ingredient in application; and physical properties, such as melting, crystallization or viscoelasticity. All of these factors are influenced by the ingredients’ chemical properties, explained Neil Widlak, MSc, Consultant, Fats and Oil Technologies in his presentation, “Factors to Be Considered for Selecting the Best Fats & Oils to Meet Clean Label Requirements.” Despite the considerations for use of such alternatives, from cost to quality to functionality, in the end, it all factors down to chemistry.
Triglycerides (TAG), esters of glycerol plus three fatty acids, form 98% of a fat’s composition, noted Widlak. The type of fatty acid—short carbon chain or long; degree of saturation (the higher the saturates, the more solid the fat); position of the fatty acids on the TAG molecule; and diversity of the TAG population—determines a fat’s properties and functionality. These properties can be changed through clean label process modifications, such as fractionation (e.g., physical rather than use of potentially objectionable solvents) and interesterification (e.g., use of enzymatic versus chemical hydrolysis).
While clean label, cold-pressed and/or expeller-pressed soybean and canola are readily available, they’re not available in the volumes (or prices) of commodity processed oils. And these alternatives may not be as easily interchanged, because of differences inherent in flavor and color—natural variances not removed during the “cleaner” extraction process. However, in terms of functionality, said Widlak, “Cold-pressed canola, expeller-pressed canola and organic canola have identical fatty acid composition vs. the commodity oil.”
A wide variety of fats can be produced with palm and cottonseed oils through fractionation. “Clean label fluid shortenings, pumpable shortenings and oleogels can be used as alternatives for plastic/semi-solid fats in many baking applications, such as cakes, muffins, cookies, brownies. However, fluid, pumpable and oleogels lack the solids and structure of plastic shortenings and may not perform as well in applications where the plastic characteristics are essential to the distinct dough layers and volume found in puff pastries and Danish-type pasties,” offered Widlak.
Palm kernel and coconut lipids, high in medium-chain saturated fatty acids, impart desirable quick melting at room temperature, but must be supplemented by the addition and or interesterification of fats having a higher melting range to achieve the desired melting range …to near body temperature to perform well in confections,” he added.
The goal of high performing shortenings or a confectionery shortening is dependent not only on its solid content and melting range, but also on the crystalline habit and behavior of the solid fats. All three characteristics must be examined and monitored throughout shelflife to ensure the shortening will meet a finished product’s performance standards.
Polyunsaturated fatty acids (e.g., linolenic [C18:3]) are more prone to oxidation and polymerization and should be kept to a minimum in oils used for frying or roasting, noted Widlak. Common varieties of soybean and canola oil contain high levels (greater than 2%) of linolenic fatty acids. High oleic varieties of these oils have been developed to lower the linolenic content and raise the oleic content, thus improving the oils frying, roasting and shelf-stability.
Research by the USDA indicates desirable fried food flavors are” contributed from the partial decomposition of linoleic (C18:2) fatty acids. Therefore, it may be advisable for oils used for frying to contain a portion of linoleic fatty acids to impart a desired fried food flavor. The ideal level would need to be determined based on the frying methods, type of food being fried and shelflife expectations,” Widlak noted.
Coconut oil does not form polymers/gums or an undesirable flavor from oxidation in popped corn because of its high levels of medium-chain saturated fat, which is very stable at high temperatures. Coconut oil is also an excellent oil for roasting, although foods with high moisture content could accelerate hydrolysis resulting in soapy off flavors in the roasted product and shorten shelflife, advised Widlak.
As he concluded, Widlak emphasized that oils, which are liquid at room temperature, cannot replace fats that are solid or plastic at room temperature and provide equivalent function/performance. It’s all a matter of understanding your application—and the chemistry within.
“Factors to Be Considered for Selecting the Best Fats & Oils to Meet Clean Label Requirements,” Neil Widlak, MSc, Consultant, Fats and Oil Technologies
This presentation was given at the 2019 Clean Label Conference. To download presentations from this event, go to https://cleanlabel.globalfoodforums.com/category/clean-label-rd-academy/
See past and future Clean Label Conference Events at https://cleanlabel.globalfoodforums.com/clean-label-events/
