Tapping into the wider industry move to reduce or remove the presence of trans-fatty acids from products, researchers from the Central Food Technological Research Institute in Mysore report that a blend of fractionated coconut oil and palm oil has the potential to replace partially hydrogenated vegetable oil.
“Melting profiles of the blends containing 30 per cent and 40 per cent palm stearins were comparable with that of a commercial bakery shortening,” wrote the researchers in the journal Food Chemistry.
In addition to offering a replacement for trans-fats, the fractionated coconut oil may also confer some health benefits of its own, said the researchers. “These blends contained 47-52.3 per cent medium-chain fatty acids which are reported to have various health benefits,” 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 Boston and Chicago, considering similar measures.
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.
The Mysore-based researchers fractionated coconut and palm oil to obtain coconut stearin of 40 and 60 per cent, and palm stearin of 13.8 per cent. They tested different blends of these stearins and found that the blends containing between 60 and 70 per cent coconut stearin (and 30 to 40 per cent palm stearins) “had the wider melting range required for plastic fats and the melting profiles were comparable with that of a commercial bakery shortening”.
Analysis of the fat composition showed that the blends contained both the lower and higher molecular weight triglycerides necessary for plastic fats. No trans fatty acids were observed in the blends, but they were present in the commercial shortening used as a comparison.
“Thus, medium-chain triglycerides-rich trans-free plastic fat suitable for use in bakery products can be prepared utilising coconut oil,” they concluded.
Source: Food Chemistry2009, Volume 114, Issue 1, Pages 270-275“Trans-free plastic shortenings from coconut stearin and palm stearin blends”Authors: T. Jeyarani, Mohd. Imtiyaj Khan, Sakina Khatoon