Many plant-based products contain FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) which are short-chain carbohydrate molecules that are poorly absorbed in the human small intestine.
These non-absorbed compounds move along to the large intestine, where intestinal microbes feed on them. This results in the production of gases that causes symptoms especially for those suffering from intestinal disorders, but also for many others.
These problems are relatively common, as it has been estimated that irritable bowel syndrome alone affects between 10% and 20% of the population.
Many foods containing FODMAPs are a good sources of fibre, nutrients and vegetable proteins, yet those suffering from symptoms will often avoid these foods and miss out on their health benefits.
In the current study researchers from VTT, the technical research centre of Finland, focused on how they might remove the two key FODMAP compounds: galactan, which is particularly abundant in beans and cabbage; and fructan, which is found in many foods including wheat, garlic and onions.
Antti Nyyssölä, senior research scientist from VTT, said: "We investigated whether these compounds can be removed from food by breaking them down with enzymes. We utilised both commercial enzymes and ones produced at VTT in the project.
"We used them to test the removal of FODMAPs from faba bean and pea protein concentrates as well as from rye, graham and wheat flour.
"The method is similar to that used to make Hyla milk, in which lactose is broken down in advance. Similarly, enzymatic treatment can be used to remove FODMAPs from food."
The solution proved to work, with only small amounts of FODMAPs remaining in the raw materials after enzymatic treatment.
Creating FODMAP free foods
The research project also tested whether enzymes work in connection with the preparation of food products. This would allow the food industry to eliminate harmful FODMAP compounds in their own processes.
The project focused on testing plant-based spoonable products, meat analogues and bakery products to investigate different types of plant-based foods suitable for the FODMAP diet.
They found that enzymes work under a variety of conditions and in different food processes.
"This is interesting new information especially for legumes, as there are currently no similar legume-based foods suitable for the FODMAP diet on the market", added Nyyssölä.
"The results are most likely to be utilised next in the development of new food items, but also in academic research in order to verify the effects on intestinal symptoms with certainty."
Better than fermentation or germination
The researchers say in their report that enzyme-aided treatments are more specific and easier to control than those based on fermentation and germination as those processes can cause side reactions which influence flavour, nutrition profile, nutrient bioavailability, and even create new FODMAP components.
For example, during sourdough-type fermentation, in addition to changes caused by microbial enzymes, acidification of the raw materials activates several endogenous enzymes (e.g. proteases, xylanases) that affect the food matrix, induce formation of flavours, and cause changes in nutritional quality.
The report explains: "Germination increases the activities of phytate degrading enzymes, resulting in liberation of minerals, such as iron, calcium and magnesium (Luo, Xie, Jin, Wang, & He, 2014; Nkhata et al., 2018).
"Fermentation has been reported to increase the bioavailability of minerals such a calcium and iron, presumably because of degradation of phytate and oxalate.
"However, fermentation may also result in release of mineral binding tannins and phenols, with opposing effects. Degradation of components such as fibres, and starch during fermentation, on the other hand, leads to loosening of the matrix structure and better bioavailability (Nkhata et al., 2018)."
This study was funded by Finnish food, feed and enzyme tech firms Gold&Green Foods, Raisio, Roal and Valio.
Source: Trends in Food Science and Technology
Poutanen. K., et al
"Reduction of FODMAP content by bioprocessing. Antti Nyyssölä, Simo Ellilä, Emilia Nordlund and Kaisa Poutanen."