A healthy outlook

By David Cowan

In recent times, consumers have been taking an active interest in food and diet. In the case of oils and fats, many consumers are aware that trans fats are linked to increased levels of bad cholesterol and cardiovascular diseases. People are becoming more aware of what they eat and no longer are health and sustainability only welcomed by a small market segment. The broader public now demands top-quality, tasty products that contain fewer additives and preservatives and are produced to highly-ethical standards. As a result, food manufacturers need to enhance their products and processes in a natural, effective and environmentally friendly way. Enzymatic solutions help the industry to meet this pressing challenge – but their use for large-scale production within the oils and fats industry has been limited – until now.

The baking industry requires margarine and baking fats of specific melting properties, that are not available when extracted from raw materials such as palm, soya bean, rape seed or sunflower oils. The most common processes used to obtain the desired consistency and melting points of fats are chemical interesterification or hydrogenation. Both require harsh processing, which often result in high levels of waste products - and hydrogenation also generates trans fats. The application of enzymes for bulk fat modification is a recent development. In enzymatic interesterification, a lipase is used to catalyse the exchange of fatty acids between the two tri-glycerides, resulting in a fat blend with altered melting characteristics compared to the original mixed fat.  The melting properties of the resulting fat are very similar to those obtained by chemical interesterification. Unlike the chemical process, the enzymatic one does not produce any by-products, resulting in an end product that is inherently more pure and containing higher levels of natural anti-oxidants. By combining different fats a range of melting properties can be obtained to produce products suitable for shortenings, margarines and cream fillers.

In addition to table margarines, shortenings and baking margarines are a major potential source of trans fat in the diet. To successfully replace partially hydrogenated fats in these products, baking performance has to be at least equivalent to the standard material. Studies on the baking performance of margarines produced from enzymatically interesterified hardstock were reported by Kirkeby (Kirkeby, P.G. Proceedings of the 94th AOCS Conference, Kansas City (2003)). During baking tests producing puff pastry, the margarine from the enzymatically interesterified hardstock gave superior results to that from chemical interesterification. Further studies made by Novozymes demonstrated that shortenings of good quality can be produced from enzymatically interesterified hardstocks using tropical oils as a base. A simple shortening produced from an interesterified mix of 50 percent palm oil and 50 percent Stearine gave identical baking performance to a commercial product containing partially hydrogenated fats.

A number of manufacturers now offer enzymatically interesterified fats and the trend is to see these replace products made either by chemical interesterification or hydrogenation. The baking industry can use these to substitute these less desirable fats without any negative impact on quality or economy. Fats obtained by enzymatic interesterification have a lower environmental impact than those derived from the older technologies, enabling the industry to become more sustainable. The process is energy efficient, easier to control and generates less waste and CO2 emissions.  As a result consumers and producers can enjoy a trans fat free product that is healthier and produced using a process, which is a better alternative for the environment.

Biography

David Cowan is the Customer Solutions Application scientist for the oils and fats applications at Novozymes. He is responsible for heading up a team of Novozymes' scientists involved in application development in the field of lipases and phospholipases for food and technical use. He has a BSc and PhD in applied microbiology from the University of Surrey (UK).