AND VALUE DRIVEN SOLUTIONS FOR BREWERY BY-PRODUCT MANAGEMENT.
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.
How it works
During the beer and spirits manufacturing process various residues are generated.
The by-products include:
- Spent grain
- Spent yeast
- Spent hops/hot trub
- Waste water
Spent grain represents around 85% of brewery waste and presents unique challenges for craft brewers including issues relating to:
- Environmental obligation
- Regulatory compliance
- Brand reputation
- Space optimisation
- Manufacturing bottlenecks
- Mess, odour and vermin
GrainOut addresses these problems faced by brewers through tailored solutions with a sustainability and value driven focus.
Brewery by-products can be considered a valuable product stream and their utilisation can be optimised to achieve solid environmental and commercial outcomes. By managing the by-products breweries can also shape the story of their product stewardship, lifecycle analytics and circular economics.
Typical disposal routes such as landﬁll for solid wastes and disposal via sewage for liquid wastes are unsustainable, potentially harmful for the brand, and less cost effective.
SPENT GRAIN REPRESENTS AROUND 85% OF BREWERY WASTE
Spent grain is generated during mashing and is removed from the brewing process from the mash tun or ﬁltered 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 suitable for sheep and cattle; dry suitable for pigs)
- Foods for human consumption
- 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%.
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.
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 at 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 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.
Dissolved brewery waste solids like excess malt, yeast and hops can bring on both a high biological oxygen demand and high chemical oxygen demand in waste water emitted from the brew house. Onsite waste water treatment may be required prior to sewer or trade waste discharge.