Oils and fats are a very important part of our daily diet and these are the richest energy sources for the body when compared to proteins and carbohydrates. They are also the carriers of oil soluble vitamins like Vitamin A, Vitamin E and Vitamin K.
Different physical and nutritional functionalities need precise compositions, which is usually not got from a single oil or natural fat. Due to this, oils and fats are often modified to get the desired compositions and nutritional and physical properties. This is where modification methods like interesterification come into play. The process of interesterification is what improves the spectrum of applications of oils and fats, which is why it is the most preferred oil/fat modification method for almost every turnkey project for rice bran oil refinery or any other oil/fat refinery
What Is Interesterification?
Interesterification (also called ester-ester exchange) is the process of redistributing the fatty acid moieties, which are present in triglyceride oil over its glycerol moieties. During this process, the fatty esters between and within tri-glycerides are rearranged, which results in modifications in the physical properties of the fats or oils. It is the intermolecular and intramolecular interchange of the glycerol’s fatty acids on the triglycerides’ backbone.
There are two kinds of interstification techniques at any interesterification plant manufacturer in the food industry:
- Chemical Interstification: Ethylate, sodium methylate and sodium methoxide are the commonly used catalysts.
- Enzymatic Interstification: Lipases like lipozyme TL1M are the commonly used enzymes.
The Impact of Interesterification on the Properties of Oils and Fats
The physical properties of fats and oils rely on their chemical properties like chain length, saturation, unsaturation and distribution of the 3 hydroxyl glycerol groups in fatty acids. Such properties get modified by modification methods like interesterification. By changing these characteristics, the range for the application of these fats and oils is enhanced.
Interesterification, thus, deals with issues of plastic fat items like texture breakdown, granular development, consistency, lumpy appearance, post hardening, rancidity and melting point and makes oils and fats more suitable for preparing margarine or deep frying.
As for the nutritional benefits, this process helps in reducing or totally eradicating transfatty acids (which increase the risk of coronary heart diseases), giving higher level of essential fatty acids.
How Does Interesterification Modify Fat or Oil?
The best aspect of the process of interesterification is that it has improved the processing technology with greater efficiency via minimal loss of oil and lower consumption of utility. As such, it is a better method when compared to the other modification methods like hydrogenation in production of solid fat. It helps in stabilising and increasing the crystal amount, which is needed for functional properties and smooth texture. Interesterification can produce softer products devoid of phase separation and lower melting point.
Here’s how it is used for modifying fats:
- Enhances the triglycerides’ compatibility in solid state
- Changes the overall melting point and meting properties
- Enhances the plasticity of the resultant solid by modifying the properties of crystallisation
- Produces a translucent waxy product for the purpose of coating
- Blends the properties of mixed fats and oils
- Blends soft oils and hard fats to the desired consistency and functionality
- Produces acceptable quality of confectionary fats
Overall, interesterification is an eco-friendly, time saving and more flexible method of modification that results in a more natural product. Now that you have understood how this process changes the properties of oils and fats in a favourable way, you would have realised why it is the most favoured modification method.