A British brewery is replacing one-third of its barley with leftover bread, CNN reported. Their goal is to reduce food waste and they’ve inspired other breweries around the world to do the same. Studies show that choosing where to get food affects the food web.
According to CNN, beer is starting to go green—and not just on St. Patrick’s Day. “A British brewer has perfected a way to turn surplus bread from bakeries and sandwich shops into a popular craft beer,” the article said. “Toast Ale uses upcycled bread (approximately one slice per pint) to replace a third of the barley typically used in beer production, all while preventing food waste and reducing its environmental impact.
“Toast Ale has collaborated with 56 breweries in seven countries to share its modern bread-to-beer method, as well as promote its greater mission of getting the entire industry onboard to combat regional waste. Increasingly, it’s not alone in this fight.”
Animals have many options for their diets, and depending on where we get our food from, the food web is affected in any number of ways.
The Bare Bones of Trophic Levels
Food webs are broken down into a hierarchy known as trophic levels, which are based on where they get their food. Plants, which get their energy directly from the Sun, are at the first level, and are called “producers.”
“We call the organisms that feed directly on plants ‘primary consumers,’ and they are at a trophic level just above the producers,” said Dr. Eric G. Strauss, Presidential Professor in Ecology at Loyola Marymount University in Los Angeles. “The secondary consumers are those carnivores that eat the herbivores. Carnivores that eat the secondary consumers are called ‘tertiary consumers.'”
Dr. Strauss said that among these trophic levels, there are groups of organisms called “decomposers.” They help recycle materials between each level, which allows energy to move between trophic levels more efficiently.
“These decomposers consume nonliving organic material that we call ‘detritus,'” he said. “This trophic level plays a key role in recycling materials back into the biotic realm. Key examples of these are fungi and prokaryotes. If you’re walking in a traditional woodland area, it’s not unusual to see mushrooms growing on wood that has landed on the forest floor or on trees that have fallen over.
“What you’re seeing is a process by which these materials are released back into the system.”
Humans play an interesting role in this ecosystem as well. Dr. Strauss pointed out that humans are omnivorous, meaning that we eat both plants and animals. Depending on where in the trophic system we choose to eat, we use energy in any number of ways.
“It takes about 1,000 calories of cereal grain to produce 100 calories of beef,” he said. “Now, those cereal grains could be humans directly, and they would provide ten 100-calorie meals, as opposed to one 100-calorie piece of beef.”
Looking at this complex movement of energy within a trophic system gives us a clearer picture of a true “food web.” Dr. Strauss said that animals in human-dominated ecosystems that can feed both as carnivores and herbivores tend to have the best success in surviving around humans.
“Each herbivore, for instance, often eats many different plants, and is preyed on by many different predators who fall into different levels of consumption,” he said. “So in nature, actual food webs are really quite complex.”
Repurposing bread to use in beer, rather than eating the bread directly or drinking beer made from another source, provides one more subtle change to the food web.
Dr. Eric G. Strauss contributed to this article. Dr. Strauss is Presidential Professor in Ecology at Loyola Marymount University in Los Angeles. He is one of the founding science directors of the Urban Ecology Institute at Boston College, where he previously was Director of the Environmental Studies Program and Research Associate Professor. He received his undergraduate education at Emerson College and earned his PhD from Tufts University.