In a food-driven world, the recovery of industrial food waste can be another profitability boost for food producers. American researchers are evaluating how to improve energy security and reduce the environmental impact by giving organic waste a second life.
“Food is the most influential force in our lives and in our world, essential to our relationships with nature and with each other.”, writes architect Carolyn Steel in the book sitopia, recently appeared in Spanish. For this reason, the author calls “urgently change the way we eat and produce food, which means we must revalue it”. In that appreciate What we eat undoubtedly includes paying attention to its complete cycle, that is, integrating food waste. And not just household leftovers, but industrial waste from food processing.
There are, for example, residues derived from wine must extraction, barley malt for beer or soy processing that have a second nutritional life, such as substances with high antioxidant and cell protective power. The bagasse (what remains of the grapes after extracting the juice), the bagasse, the alperujo from the mills (after the oil is made) and the okara (or soy pulp) are considered organic residues that, due to their properties, can continue to nourish us, like ingredients in other processed foods or dietary supplements.
Usefulness of food waste
Several studies have found use in other food industry waste, which could be transformed into car tires or biofuels. It is the cases of tomato peel and eggshell that have proven their effectiveness as rubber substitutes, without going any further. There’s also extra life for potato skins, fried dough crumbs, cheese whey and other waste products from industrial food processing, which invariably end up in landfills, and which could be used to obtain biogas and electricity, or organic fertilizers.
Thus, along with the valuable artisanal recycling to obtain compost that many families already practice, there are scientists who have proposed to go a step further, with the aim of estimating the best large-scale uses for organic waste from food processing. Therefore, it was necessary to exhaustively analyze its content and, based on these findings, propose production opportunities, which will take into account its valuation.
Economical ways to use food waste
A study developed by a team from Ohio State University (USA), and recently published in the journal Total Environmental Science, proposes cost-effective ways to use industrial waste, which could make reducing greenhouse gas (GHG) emissions tempting also for industrialists in the food sector.
In their work, the researchers announce that there is money to be recovered and the potential to contribute to the fight against global warming, finding a new use, on a large scale, for the millions of tons of garbage that are dumped into sewers each year or accumulate in sanitary landfills. To do this, it is crucial to determine the potential value of what normally goes to waste.
It’s a waste,otherwise they would be useless or even a drain on resources for a company, which has to spend money to eliminate them.“, explained, in the presentation, Katrina Cornish, author of the study and professor of Horticulture and Crop Science and Food, Agricultural and Biological Engineering at Ohio State University (USA).
This scientist of bioemerging materials points to bioeconomics as an essential discipline to implement new business models, based on successful experiences in this industrial sector.
What ‘goes to waste’
For this work, a total of 46 waste samples, including 14 from large Ohio food processing companies, were collected and divided into four broad categories: vegetable, greasy waste, industrial sludge, and starch. They characterized the physical and chemical properties of the sample content and proved that some starchy residues were good candidates for fermentation in chemical acetone factories (used in the manufacture of plastics, fibers, medicines, among others).
In general terms, the energy density of a type of waste – based on calorific value – and the carbon-nitrogen ratio were the main elements evaluated to determine its reuse potential. For example, fatty and mineral residues can be transformed into biogas, through the process of anaerobic digestion (or biomethanization). The remaining soybeans have sufficient energy density to be used in the production of biodiesel.
It is clear, then, that low-calorie vegetable scraps are not best suited for energy production, but they provide abundant organic sources of flavonoids, antioxidants and pigments that could be extracted and used in health-beneficial compounds.
bioemerging materials
As for other bioemerging materials, study lead author and Ohio State University researcher Beenish Saba explains that “there is ample room for the development of bio-based products”, which obviously includes “the use of biological waste as components of materials and processes”. On the other hand, he emphasizes, “thermochemical liquefaction and anaerobic digestion obviate the need to dry waste prior to use and should be explored in this context”.
This work, which meets the objective of the Environmental Protection Agency The US goal of reducing food waste by 50% by 2030, according to the author, may provide one of the methodological keys to reducing this loss: the “valuation” of waste.
Asked about the best opportunities for large-scale use of this type of waste, Saba maintains that “the construction of a biorefinery for fermentation or electrofermentation of residues for the production of chemical compounds can represent this opportunity”.
Taking into account the ecological footprint of food waste
In addition, regarding the concrete possibility of large food processors systematically taking into account their ecological footprint and considering extending the useful life of their raw materials, the scientist guarantees that there are already industrial producers who “They are starting to track data on their environmental impact, in response to federal government requirements.” That is why, he details, that even at the university level there is hope that some of them “will be willing to work together with scientists to develop models of data that may be useful”.”.
The scientist insists thatThe recovery of food waste is important to reduce waste management costs and, at the same time, reduce gas emissions associated with its discharge or disposal.”. So, in his opinion, “industry should support university research to generate primary data in the field of waste recovery food”. He further adds that theCommitment to the United Nations Sustainable Development Goals (SDGs) can inspire environmental protection agencies to develop funding plans for research in this area by research institutes and universities”.
Calculating new uses for food waste
While this study is a starting point, as the authors acknowledge, the idea is that food producers will find incentives to consider doing something with food waste that is currently treated as garbage.
Corn is already being grown to be transformed into biofuel, acetone and butanol, so this work, supported by the Department of Agriculture of the United States National Institute of Food and Agriculture, seeks to identify other sources of food waste already available, which can also they become products with new life.
This is how Saba puts it: “Proposed conversion technologies require energy to operate and also produce other secondary wastes, but the valuation model lays the groundwork for renewed analyzes of the full life cycle of food and its wastes, which would help to quantify the environmental benefits of waste reduction. on a large scale”.
What they expect from the University, as Cornish confesses, is that “growers really analyze their costs and footprints and see which of these approaches might work for their waste, which would be the least harmful, financially (and preferably profitable) and which will also minimize any carbon footprint”. With regard to the contribution to the fight against climate change, “any waste that can be recovered has a direct impact on emissions that cause global warming and on the ecosystem”, emphasizes.
Lastly, Beenish Saba is committed to the wide communication of scientific advances to public managers and the population in general to “raise awareness” about the performance that garbage can offer.
From salt to hydrogen
Other energy sources can even come from cheap and common seasonings like salt. Large underground deposits of this chemical compound can serve as hydrogen tanks, conduct heat for geothermal power plants, and provide solutions for CO storage.twoaccording to a recent study led by Economic Geology researchers at the University of Texas and published in the journal tektonika.
Historical knowledge about salt and its deposits can also play other relevant roles in the energy transition to cleaner sources: “We see potential in applying the knowledge and data gained from many decades of research, hydrocarbon exploration and mining in salt basins to energy transition technologies.,” states lead author Oliver Duffy.
The researcher also maintains that “a deeper understanding of how salt behaves will help to optimize the design, reduce risk and improve the efficiency of various energy transition technologies”.
In fact, salt influences the formation of the Earth’s underground layers. Geological forces easily squeeze it together to form complex, massive deposits and these structures offer a “range of opportunities for energy development and emissions management“, according to Lorena Moscardelli, co-author of the study.
Storing gases or liquids underground
As for the possibility of storing gases or liquids underground, there are already certainties about the behavior of salt domes as containers of proven efficiency, used by oil refineries and the petrochemical industry. According to the document, these salt formations could also be used as deposits of hydrogen for energy production. What’s more, the porous rock surrounding them could be used for permanent storage of CO2 emissions.
Finally, the article also discusses how salt can contribute to the adoption of state-of-the-art geothermal technology. While the industry is still in its early stages, the researchers show how the salt’s ability to easily conduct heat away from warmer underlying rocks can be harnessed to produce geothermal energy.
References:
B. Saba and others. “Characterization and potential valuation of residues from industrial food processing”. Total Environmental Science (2023).
Duffy, O. and others. “The role of salt tectonics in the energy transition: an overview and future challenges”. tektonika (2023)
