Green Beer, part 3
Waste Not Want Not
Features
November 11, 2004
Written by jercraigs
Last week we looked at the materials needed to deliver a tasty beer to your glass. This week we delve into the materials used in the brewing process itself, specifically the stuff that ends up leaving the brewery as waste. This includes spent grains, yeast, hops and wastewater, and it represents not only waste materials but also wasted energy as well. The energy in waste typically receives less attention than the energy required by manufacturing processes, but it is an important part of a holistic view of the brewing process. Peter Coors, CEO of Coors Brewing Company, notes the importance of waste reduction by saying, "Find pollution or waste and you’ve found something you have paid for but can’t sell - you’ve found inefficiency."
According to Gunter Pauli of Zero Emissions Research Institute (ZERI),
up to 92% of the ingredients used in brewing ultimately become waste.
One of the goals of ZERI is to channel all of a brewery’s waste
product outputs, into inputs for other industries. I will also discuss
this further when I profile Storm Brewing in Newfoundland where they
are striving to employ ZERI principles. If you are eager to learn more
now, you can read more at <a
href="http://www.zeri.org">www.zeri.org.
Grains and Malt and Happy Cows
A large portion of brewing waste is made up of spent grains - the malt
and grains leftover after the sugars have been extracted in the
brewing process. Spent grain is about 70% fiber and it is typically
sold to farmers for cattle feed in North America, where farms and
cattle ranches can typically use as much spent grain as the breweries
produce. Brewers can’t just use less grain since this is pretty much
what makes up the beer, so finding ways to dispose of it is important.
Brewers have found innovative ways to use their spent grains over the
years. At Miller Brewing spent grains are seen as an opportunity, and
they have set up a by-products business to find new uses for its grain
waste. Marketed under the Barley’s Best brand name, spent grains are
sold to farmers and commercial bakeries as a fiber supplement.
Anheuser-Busch similarly keeps its spent grains out of landfills by
feeding most of it to dairy cows. In one year 1.76 million tons of
spent grains fed more than 200,000 cows!
Old beer past its expiry date can also be mixed with animal feed and
fed to livestock as well. In Alberta, Molson’s outdated brews were
mixed with the regular cattle feed to create a porridge-like mixture.
Each cow receives a daily ration of 10 pounds, or about 12 bottles
worth of beer mixed with 40 pounds of feed. They don’t have to worry
about the cows getting drunk though, since the cows’ complex stomach
system breaks down the alcohol in beer, transforming it into food
energy.
Farmers willing to cart away spent grains for free find that word
quickly spreads amongst local breweries. A dairy outside of Cleveland,
Ohio began collecting grain from Great Lakes Brewing Co., and soon
found itself collecting enough spent grains from local breweries to
warrant the purchase of a small dump truck to help with pick up.
According to their website, Great Lakes currently has partnerships
providing spent grain to producers of organic beef, mushrooms and
produce, and are researching the idea of locally grown hops.
In Ontario, Black Oak Brewing and Cameron’s Brewing in Oakville have
their spent grain picked up by a local dairy farmer providing
approximately 5% of his total feed needs. John Graham of Church Key
Brewing tells us that feeding his spent grains to local dairy cattle
while it is still warm can actually increase milk production in cows
accustomed to a cold diet, which he attributes to warm happy cows.
Speaking of happy cows, the gourmets among us probably know that the
cows used to make the world renowned Kobe Beef from Japan are fed a
diet of beer, massaged, and brushed down with sake. The cattle are fed
beer during the summer months to stimulate their appetite. Apparently
the interaction of fat cover, temperature and humidity during the
summer depresses feed intake.
Rudolph The Red Nosed Grain-Deer
Isolation can also be a factor in disposing of spent grain. Breweries
in Alaska for example face the potential double whammy of having to
first import grains to brew with, and then pay again to export the
spent grains. Brewers in Anchorage were happy when a local farmer
began collecting their spent grains and feeding almost a ton of it a
day to his reindeer.
"Reindeer love the stuff, and tolerate it well," he says. "Some of it
comes in large garbage cans and it freezes. We just haul it out there
frozen, turn it upside down, and they eat it like a reindeer-sicle."
Midnight Sun Brewing Company was paying to have the grains shipped off
to a composting facility prior to the introduction of the reindeer
farm, and they are currently sending their grains to a local hog
farmer.
Alaskan Brewing in the coastal town of Juneau is not so lucky. Without
road connections to the lower 48 states, everything comes and goes by
water or air. They have to have their spent grain dried, packaged and
shipped south by barge where it is fed to Washington livestock or used
as compost. To save on shipping costs on the barge the brewery
installed a grain drying system, the first craft brewery in the
country to do so. Dry grain weighs less and is therefore cheaper to
ship. To save on heating fuel costs for drying the grain, their grain
drier burns about half of the dry grain produced to make more heat for
drying. The grain drier uses half heating oil and half dried grain,
reducing the brewery’s need for fossil fuels. Other means of local
disposal are limited but include donating grains to local community
gardens, composting projects and a local manufacturer who makes pet
treats for cats and dogs. Alaskan Brewing was also the first craft
brewery in the US to install a CO2 recovery system, which has allowed
them to be CO2 self sufficient for the last three years.
For more details on brewing in Alaska see <a
href="http://www.anchoragepress.com/archives/document01cf.html">
www.achoragepress.com
In areas without large livestock industries, spent grain may end up in
landfills, often the most economic disposal method available. While
spent grain contributes healthy biomass to landfills, it can be used
more efficiently as compost for farming, particularly mushroom
cultivation. (I will discuss two breweries that make use of grain in
this manner – Great Lakes and Storm Brewing – in later weeks.)
Alternate means of spent grain disposal include using them as filler
in pet food, or even people food. Many brewpubs offer spent grain
bread on their menu, and under the ZERI model this is an important
means of creating extra income for the brewer. (Not to mention tasty!)
Fun with Science
There some to have been a large number of scientific studies on uses
for spent grains and other brewery wastes around the world.
Researchers in Japan have investigated the possibility of direct
conversion of spent grains to gas. A reactor was used to convert the
spent grain to carbon dioxide, methane and hydrogen gas. The gas can
then be used as a fuel cell energy source.
In China, Foster’s Tien Giang has found an innovative way to protect
local crops against fruit fly infestations by utilizing brewery yeast
waste to process fruit fly bait. The process benefits farmers by
increasing their crop yields, but also finds a beneficial for the
brewery waste.
Polish researchers have experimented with using the protein from spent
grains as a cultivation medium for studying microorganisms in soil
samples. Their studies show that the spent grain medium allows the
isolation of actinobacteria, especially Streptomyces, and enhances the
sporulation. (I have to confess – I am still a little fuzzy on what
exactly that means even after having it explained to me by a
microbiologist, but it sounds pretty cool.)
Still to Come
Well, it seems I had more to say about the myriad of uses for spent
grain that I had anticipated, so I am going to hold off on talking
about wastewater until next time. As always I appreciate comments and
questions so keep that beermail coming!
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"Reindeer love the stuff, and tolerate it well," he says. "Some of it comes in large garbage cans and it freezes. We just haul it out there frozen, turn it upside down, and they eat it like a reindeer-sicle."
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