Fermentation may have been a greater discovery than fire
Beer is the fifth most consumed beverage in the world behind tea, soft drink, milk and coffee, with an estimated annual world production of over 1.5 billion hectolitres. Australians are world class beer drinkers ranking fourth internationally in per capita beer consumption.
In the manufacture of beer various residues and by-products are generated, and with our foundation in product reuse and clever waste management principles, Benzoil works in with brewers big and small to trade excess by-products. We can establish long term strategic offtake agreements.
The process of brewing beer unavoidably generates by-products and waste. Technology has allowed a refinement of processes to reduce the amount of waste produced and to generate useful materials from the by-products including:
- Spent grain
- Spent yeast
- Spent hops/hot trub
- Diatomatious earth
These brewery by-products can be considered a valuable product stream and their utilisation can be optimised to achieve solid environmental and commercial outcomes. As well, this helps in shaping the story of the brewery in relation to product stewardship, lifecycle analysis and circular economics.
Typical disposal routes like landfill for solid wastes and disposal via sewage for liquid wastes are unsustainable, bad for the brand, and not to mention expensive options for brewers. Especially in the case of craft brewers, many have taken up quick disposal options for waste streams and by-products without considering the full range of options.
Spent grain is generated during mashing and is removed from the brewing process from the mash tun or filter before the boiling stage. Brewery grain is the most abundant brewery by-product. It is high in protein and fibre. Uses include:
- Animal feed (wet good for sheep and cattle; dry good for pigs)
- Foods for human consumption
- Feedstock for biofuel manufacture
The protein and high fibre concentration of spent grains support rumen function and animal production. Wet spent grains are a good source of protein with a crude protein content that ranges from 25-34%.
Spent hops and hot trub
Spent hops or hot trub are most often removed from the brewing process as by-products from the wort production process before the fermentation occurs, however late hopping and dry hopping techniques can introduce hops are other stages. Over three quarters of hop material added to beer will become a by-product and require disposal. Uses include:
The residual bitterness of spent hops makes it nearly impossible for it to be used as an animal feed. Although convenient for smaller brewers, those who add their spent hops to their spent grain for disposal risk compromising the grain’s compatibility for animal feed as the high alpha acid content can be distasteful for cattle and sheep.
During the fermentation process yeast cells multiply numerous times resulting in a massive yeast mass, essential for a robust fermentation. Similarly to spent grain, brewers can utilise spent yeast in applications comprising animal feed, compost adjunct or human food supplement. Spent yeast is a potential good source of minerals, B-complex vitamins, and high quantities of essential amino acids.
Benzoil’s Feed & Fuel division markets wet grain and specializes in the timely removal of spent brewers grain and subsequent delivery of these processed grains to nearby cattle feedlots. The physical form of the product is a wet, loose, fibrous grain residue comprising an excellent feed for ruminants containing a good source of digestible fibre and concentrated protein. A nutritional analysis is available on request. We also provide associated yeast slurry removal services from micro brewers.