Trans-fat free shortenings show bakery potential
When used as a shortening in cookies, the blend of high oleic sunflower oil, fully hydrogenated canola oil, and fully hydrogenated soybean oil was found to offer trans-fat free alternatives for the bakery industry.
“Chemically randomized blend of a 30 per cent stearic acid-rich and oleic acid-rich can be used as a zero trans shortening,” wrote Alejandro Marangoni and Latifeh Ahmadi from the Department of Food Science at the University of Guelph report their findings in Food Chemistry.
“This high stability shortening can find application in deep fat frying and many all-purpose bakery applications.
“This product had a comparable plasticity and melting characteristics as a commercial shortening, but with the added health benefits of high stearic and oleic acids,” they added.
Trans fats and heart health
Though trace amounts of trans fats are found naturally, in dairy and meats, the vast majority are formed during the partial hydrogenation of vegetable oil (PHVO) that converts the oil into semi-solids for a variety of food applications.
Trans fats are attractive for the food industry due to their extended shelf life and flavour stability, and have displaced natural solid fats and liquid oils in many areas of food processing.
But scientific reports that trans fatty acids raise serum levels of LDL-cholesterol, reduce levels of HDL-cholesterol, can promote inflammation can cause endothelial dysfunction, and influence other risk factors for cardiovascular diseases (CVD), has led to a well-publicized bans in New York City restaurants, and other cities, like Chicago.
In the food industry this has been mirrored by an increase the in pressure on food manufacturers to reduce or remove trans fatty acids from their products and reformulate.
The food industry as a whole has expressed its commitment to removing trans fatty acids from its products, but such reformulation is not straightforward and presents challenges.
Commercial baked goods such as crackers, cookies and cakes, along with many fried foods, like french fries and doughnuts contain trans fats.
In their new study Ahmadi and Marangoni chemically interesterified high oleic sunflower oil, fully hydrogenated canola oil, and fully hydrogenated soybean oil in a weight ratio of 70:17:13. The resulting shortening was then used in the preparation of chewy brownie cookies.
According to their findings, the resulting fat had comparable plasticity, solid fat content, and melting points as a commercial shortening.
Furthermore, results of sensory analysis showed that tasters accepted both conventionally produced cookies, and cookies made with the trans fat-free shortening equally.
The study was funded by the Natural Sciences and Engineering Research Council of Canada and the Ontario Ministry of Agriculture, Food and Rural Affairs.
Source: Food Chemistry
Volume 117, Issue 4, Pages 668-673
“Functionality and physical properties of interesterified high oleic shortening structured with stearic acid”
Authors: L. Ahmadi, A.G. Marangoni
