Recovery of residual materials from the brewing process to CO2 neutrality: Steinecker uses spent grains and yeast as sources of protein and energy

  • One of the latest Brewnomic modules – A holistically designed solution for recycling residual materials from the brewing process and using them for energy recovery is examined and optimized in a pilot plant as part of a development project Steinecker.

  • One of the substances that can be extracted from brewers’ grains is protein, for which we currently see a very high demand not only in the food and beverage industries, but also from producers of food supplements or cosmetics.

  • Once the valuable constituents have been separated, the remaining biomass is much easier to process in a biogas plant with the current state of the art than it would be without pretreatment.

For most breweries, brewing grains are just what is left over after brewing and are often simply used as animal feed. In some cases, breweries even have to pay for their disposal. But in reality, much, much more hides in the waste material from the brewing process. They not only provide rewarding options in terms of sustainability, but also profitable additional business for breweries. A joint project by Steinecker and the two development specialists, Professor Waldemar Reule and Dr Rainer Gottschalk, shows how this can be successfully managed. The concept they developed is now for the first time translated into workshop reality at the Ustersbacher Brauerei in Bavaria.

From residual to raw material

Dregs and yeast are residual materials that contain proteins. And it is precisely this protein that now takes center stage. While the Brewnomic has so far focused solely on the use of residual materials for energy recovery, the project team has in the meantime developed a material recovery process. This process consists of three steps:

  • First, proteins are extracted from residual materials. This is done in a three-vessel system, similar to the concept of the CombiCube brewhouse. After dispersion and hydrolysis, the proteins are separated by membrane filtration.

  • In the second step, the remaining biomass is acidified. Then the mineral fertilizer is obtained by means of an ion exchanger.

  • This is followed by energy recovery in the form of biogas production. The wastewater from the brewery is also added and purified there.

Protein – highly sought after on the market

Protein extraction is particularly profitable for breweries. Thanks to trends towards a sustainable, healthy and vegan lifestyle, the demand for plant-based protein sources is increasing in the manufacturing industry. Potential buyers of this highly sought-after raw material are not only dairies and food factories, but also producers of food supplements and the cosmetics industry. In addition, the sale of the mineral fertilizer and the savings made through the biogas supply also pay off for the brewery. Thus, the sum of the annual revenues results in a return on investment (ROI) of only a few years, significantly lower than that of a conventional biogas installation where spent grains are only used for energy recovery.

First use in the Ustersbacher Brauerei

The Ustersbacher Brauerei in Bavaria will be the first to use the concept developed for the recycling of spent grains in the reality of the workshop. The prerequisites are ideal: “Over the past ten years, we have already implemented a number of measures. With each of them, we have taken one step at a time towards achieving our goal: to become an energy self-sufficient brewery. using the Brewnomic concept. It is therefore logical that our goal now is also to use the residual materials from the brewing process as sustainably as possible,” explains Stephanie Schmid, owner and manager of the brewery.

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Krones AG published this content on January 26, 2022 and is solely responsible for the information contained therein. Distributed by Public, unedited and unmodified, on January 27, 2022 12:28:01 UTC.

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