Fat is a multi-purpose ingredient, offering taste and texture, making it difficult to find a simple alternative to replace it. We talked to Dr. Clara Talens (AZTI) about the technical challenges of replacing the fat content in food.
Do you think there is a way to not only create substitutes for fat in the food but also make sure it doesn’t lose any of its functionalities?
"In the long term, what we need to do is to create structures that mimic fat. That is of course already being done, but it needs to be looked at from a more sensory point of view. There has been research done on replacing fat and science has focused on the physiological effect and the sensory effect has been forgotten a bit.""So what we have to do now is to develop structures that mimic fat in the mouth. That is the most important thing, because if the consumers, when eating a product, associate that is very similar to fat, they will choose this product. So we need to focus more on the sensory properties of fat, than on what we are losing physiologically when we are replacing.""What we do not have now, is similar taste so that is, in my opinion, what we should focus on. There are four flavours; salt, savoury, acid and bitter and the fifth newer one, umami, - and now there is another one connected to fat as it concerns lipids, so I think that the trend should go that way."
What are the challenges that science needs to overcome in order to reduce fat?
"The challenge is going to be the future ingredients that are going to replace fat. What has happened until now is that there have been a lot of resources in obtaining fat substitutes that are really pure and that makes them really expensive and unsustainable because the process to obtain these ingredients requires a lot of energy.""I think that in the future there is going to be more focus on understanding the relationship between structure and composition of these fat substitutes, in order to get ingredients that are not as pure so we can have a more sustainable processes applied to these fat substitutes that give us the physico-chemical sensory properties that we want. The main issue is not going to be the fat substitute itself, but the process to obtain these fat substitutes, because right now they are very expensive, so when you compare the ingredients of a common product with a low fat version, the low fat has much more ingredients and the ingredients are much more expensive because they are expensive to produce. So the price is one of the main challenges we are already facing."
What is the connection between fibres and fat replacers?
"Fat replacers, chemically speaking, are also food and they can either be carbohydrate-related, protein-related or even lipid-related. So fibres are carbohydrate-derived fat substitutes, that is why they are related to fat substitutes: because they are carbohydrates. They are not absorbed by the intestine and that is why their caloric value is 2kcal per gram and when you use fibres, the caloric value of the product is reduced - so that is why they are considered fat substitutes."
Is there a different procedure of fat replacement between semi-solid foods and liquid or solid foods?
"The properties that you measure are different and not the procedure per se. So, if you do fat replacements in a liquid food, for example cream or puree, you are going to look for viscosity, texture in mouth, granulosity, creaminess - fat perception is more related to viscoelasticity properties. But with a solid food, like bakery, you are going to look for properties like sponginess, aeration, ease of chewiness and properties more related to biting."
What makes fat so unique and difficult to substitute from a technical point of view?
"The uniqueness of fat is that you can get many things with this one ingredient: You have colour, appearance, textural properties because they create these moisture-like perceptions. When you remove fat you have a more dried texture, and of course, you have flavour and aroma. So you have to at least replace all these attributes with other ingredients."
What are your predictions for the F&B industry over the next 3-5 years?
"The thing is that is happening with globalisation is that it is not serving everyone. At the moment, in the USA, if you visit Silicon Valley more specifically, it’s a trend to create start-up companies related to food and they are discovering the food industry and all the money that comes from food, because after all we all need to eat. What we see with these companies is that they are getting into the food market without knowing anything about food and that is dangerous in a way, because they can manipulate consumers and consumers many times are not aware of what is good and healthy for them."
"Our role here is to create opportunities for all to contribute to create a wider range of healthy choices. The problem now is that there are not many healthy choices and consumers do not want the choices they find in the market. We need to research why this is happening and offer them healthier choices and inform them of the consequences of their diet.""Another thing is regulation; take for example sugar taxes that are imposed in European countries. My prediction is that the next form of taxes being imposed is going to be fat related. We have to move forward to consumer business because ultimately, they have to be the bosses of what they consume."