Pink Slime Bad, Green Slime Good

Jamie Oliver’s public exposure of ‘pink slime’, a waste meat product processed with ammonium hydroxide to eke out hamburger meat and make it more profitable, eventually led to MacDonalds and other fast food chains to stop adding filler we wouldn’t even feed our dogs to their hamburgers. Ironically, you’re better off eating a MacDonald’s hamburger than buying ground beef at your local supermarket to make your own, as 70 percent of it still contains pink slime, something you won’t find on the label.

In Australia, there’s been a recent hullabaloo over ‘permeated’ milk, or milk that has diluted with anywhere from 15% to 35% of a lactose by-product of cheesemaking, something milk producers don’t mention on the label. Permeate diluted milk is nutritionally no different than undiluted milk, although it tastes blander and spoils more quickly. On the other hand, all milk contains permeate; it’s a natural component of milk that comes out of the cow, not a chemistry lab. And this newest scare about our food safety has seen ‘permeate-free’ milk shoot up in price, the milk industry reaping unwarrantable profits off consumer fears. Permeate isn’t harmful, nor technically is pink slime – it’s just distasteful, pun intended.

On a more positive note, not all slime is repugnant, despite our initial misconceptions. Pink slime may be bad for you, but green slime quite definitely has the potential to be our best friend, maybe even the salvation of our planet. Long regarded as more nuisance than blessing, this fast-growing green slime in our swimming pools, our ponds and rivers, our aquariums, researchers have only recently started to realize the enormous potential of this tiny organism.

A PNNL study shows that biofuel made from algae grown in huge outdoor ponds could replace 17 percent of the State’s imported oil for transportation. Some algae species are naturally capable of producing 50% or more of their own weight in lipids, and current bioengineered strains can produce up to a whopping 80%, as well as double their mass in less than 24 hours. Some strains can double their growth in eight hours. Compared to soy beans, which are typically 20% lipid content and yield 4,000 gallons of biodiesel fuel per acre annually, algae grow in open ponds can produce 50,000 gallons per acre annually, and developers are working toward closed photo bio reactor systems that would increase this production up to over 100,000 gallons per acre per year. Algae biofuel can be produced up to 500 times the production rate per acre of any other source of vegetable oil, and Unlike soy beans, camelina, rape seed and palm oil, algae doesn’t diminish feedstock production or devastate fragile ecosystems.

But the good stuff doesn’t stop there. How about street lights powered by algae? French biochemist Pierre Calleja has designed a streetlight powered by micro-algae that not only produces useable light but absorbs one tonne of CO2 per year, or as much as a single tree can absorb over its entire life. One of his eerily green lamps has already been set up in an underground parking garage in Bordeaux. The light generated by algae is never going to light up a ballpark, but algae-generated lighting can be used as ambient light in homes and shops, as well as functioning more as a CO2 scrubber and air purifier. As 25% of CO2 in the air is generated from car exhaust, micro-algae generated roadside lighting could absorb tonnes of emissions straight from the source, killing two birds with one stone. Calleja’s lamps are composed of a large tube containing microalgae, as well as a battery that charges during the day via photosynthesis of the algae, using both solar power and CO2 (both of which are usable by the plantlife), and storing power at night, producing electricity-free lighting even for locations where there is no or little natural light, such as underground parking garages.

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Other algae are being investigated as a possible source of alternative light – including one that has been known for centuries, the seasonal bloom of bioluminescent dinoflagellates in seawater and light up the surf at night. There are many species of bioluminescent bacteria, including Pyrocystis lunula, Pyrocystis noctiluca and Pyrocystis fusiformis, all available commercially. A ‘bio-light’ concept designed by the Dutch electronics company Philips utilizes these bioluminescent bacteria’s chemical reaction of an enzyme called luciferase on a light-emitting molecule called luciferin which glow green when fed methane gas, lighting up a series of beautiful hand-blown glass jars held in place by a steel frame. Although the light isn't bright enough to fully replace conventional lighting, it can be applied to such areas as illuminated walkways and ambient mood garden lighting, safety lighting on road verges or warning strips on flights of stairs. These same bioluminescence techniques could be used as a diagnostic indicator of pollution levels or even as a biosensor for monitoring diseases like diabetes. But as an added bonus that standard LED or other low-energy lights don’t have, the methane gas the bioluminescent bacteria feed on are produced through a household waste digester composting vegetable scraps and – ahem – ‘bathroom solids’ (or more colloquially, ‘poo’), reducing CO2 emissions and sewage waste.

Venice is developing a $264 million plan to generate 50% of the electricity needed to power the city centre using two kinds of common algae found attached to ships, Sargassium muticum and Undaria pinnafitida, brought into the seaport from Japan, China, Korea and France to breed in the city’s canals, causing headaches for gondolas and ferry boats. Asian kelp is on the Global Invasive Species Database, forming dense forests that compete for light and space with the lagoon’s native plant and animal life, growing up to three metres. The algae will be cultivated and treated to produce a fuel to turn turbines in in a new 40 MW power plant. Carbon dioxide produced in the process will be fed back to the algae, further reducing CO2 emissions.

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And should you want to make your own cool algae ‘lava lamp’, check out the Latro Lamp by Eindhoven designer Mike Thompson on his website. He advocates treating his algae like you would a pet, with proper feed and care. Breathing into the handle of the lamp provides the algae with CO2 while the side spout allows addition of water and expulsion of oxygen. During the day, a light sensor monitors light intensity as the algae uses sunlight to synthesize food from water and CO2, permitting electron leeching only when the lux level passes threshold to keep the algae well fed and happy. Energy produced by happy algae is stored in a battery, and used at night.

Unlike pink slime, green algae are also a rich source of Omega-3 DHA, a long-chain essential fatty acid the human body cannot synthesise adequately on its own. Traditionally, DHA rich fish oil was made from tuna and salmon, then – as marine stocks of fish plummeted – krill was harvested as a viable substitute. Krill, tiny relatives of shrimp living in the Antarctic, comprise the largest animal biomass on the planet. But concerns over the sustainability of krill harvesting arose when animal populations that depend on krill sharply declined, prompting the Commission for the Conservation of Antarctic Living Marine Resources to change quotas and restrict fishing areas. Once again, our friend, pond raised green algae has proven to be a sustainable alternative source of DHA, suitable for vegetarians as well as kosher, and organic.

Embrace the green slime. Good for you, good for the planet.

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