Positive nutrients of wheat

The benefits of eating wholemeal products are undisputed, as it is the outer layers and the germ of the grains that contain the many particularly beneficial nutrients, namely minerals, dietary fibre, vitamins, essential amino acids and trace elements. Over 25% of our daily requirement of minerals and dietary fibre comes from wheat. The inside of the grain, the endosperm, contains a lot of carbohydrates and proteins, about 20% of our daily requirement comes from wheat. Of course, we should not only eat wheat, but numerous health organisations recommend 2-3 slices of wholemeal bread per day as part of a balanced diet. In many regions of the world, the supply of meat, vegetables and fruit is much poorer and wheat and its nutrients are even more important there. However, it is crucial that we eat more wholemeal, as the particularly valuable nutrients in white (extracted) flour have been sieved out. When baking with wholemeal flour, it is also very important that the dough is fermented for a longer time ideally with sourdough, so that the minerals such as iron and zinc are also bioavailable to us.

Individual varieties of wheat and especially the different species einkorn, emmer, durum wheat and spelt differ greatly in terms of these nutrients. Unfortunately, there are only few scientific studies on this topic, which often look only at bread wheat and disregard possible environmental influences through cultivation practices and the like. And in the cultivation and processing of bread and other products, such issues have played no role at all to date; when selecting varieties, the main factors are yield potential, resistance to diseases and baking quality. In several studies, we have been able to show that nutrients such as amino acids or minerals can be influenced along the supply chain. Each partner in the supply chain has the opportunity to actively influence them, albeit with varying degrees of efficiency. For example, it makes little sense to go to great lengths to increase the mineral or fibre content in wheat breeding if the consumption of wholemeal wheat remains very low because these ingredients are only contained in wholemeal and not in white flour. If the issue is to be tackled seriously, rapid technical methods are needed to measure nutrients along the supply chain. However, things will only change if we consumers show more interest in this or if wheat is also paid for on the basis of such nutrients. Incidentally, these nutrients are also partly responsible for flavour development, which is a positive aspect. We are currently pursuing research into nutrients in wheat that are of interest for human nutrition in our Betterwheat research project. 

Einkorn is an example of what alternative species can offer. Einkorn contains many important nutrients in much higher concentrations than wheat. Its content of minerals such as zinc, selenium, manganese, copper and iron is up to four times higher than that of bread wheat. Einkorn has twice as much fat as bread wheat and a better fatty acid composition. It contains mainly monounsaturated fatty acids and less saturated fatty acids, which has a positive effect on the freshness of the einkorn product in addition to its health benefits. Compared to bread wheat, einkorn has up to 8 times more lutein and carotenoids, which are also said to be beneficial to health. Lutein also gives einkorn flour a very yellowish colour and a unique taste. Low lipoxygenase and α- and β-amylase activities also mean that the good ingredients are not broken down to any great extent during bread production. For experts, I recommend the review article by Hidalgo and Brandolini and especially the work of Jochen Ziegler, Sabrina Geisslitz and Muhammad Afzal.

Another question is flavour, and more specifically, whether there are wheat varieties that make bread taste more intense and aromatic. The answer is yes! Together with the craft baker BeckaBeck and the craft miller Hermann Gütler, we were able to show that there are spelt varieties that improve the flavour of bread. What's more, this appears to be genetically determined, so we could select for it in future, i.e. try to generate varieties with not only better yield and baking properties, but also better flavour. Whether this is realised, however, will be decided by the market or the consumer, who in the simplest case would be prepared to pay a little more for it.

We were also able to confirm these findings for wheat. We were also able to clearly refute the hypothesis that old wheat varieties taste more flavoursome than modern wheat varieties. The length of the dough fermentation also has an important influence on the taste, colour and freshness of bread. And the dough fermentation is THE method for making minerals in wholemeal grains available in the first place. Some of these are bound by phytate in such a way that they cannot be absorbed by our intestines. Prolonged dough fermentation, especially with sourdough and rye, greatly reduces this phythate and makes iron, zinc etc. available to us.