Food waste is a growing environmental problem, and scientists made a small system that uses black soldier flies to turn scraps into animal feed and frass (insect manure). The goal is a low-cost, local alternative to large industrial facilities.
The DIY bioreactor is cheaper and more accessible than commercial operations and can be built from off-the-shelf materials and run by one person. Researchers tested the design with food waste from a campus dining hall and found it became stable and produced larvae on a regular basis.
The larvae are rich in protein and good for poultry and fish. The bioreactor also makes frass, which helps soil and appears to boost plant defenses. Operators must keep the space cool and shaded and add water or wood chips as needed.
Difficult words
- bioreactor — a device that uses organisms to process material
- frass — insect manure used as plant fertilizer
- larva — young form of some insects before becoming adultlarvae
- scrap — small leftover pieces of food or materialscraps
- accessible — easy to reach or use
- industrial — connected to large factories or production
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Discussion questions
- Could a small bioreactor like this work where you live? Why or why not?
- Which food scraps from your home would you put in the system?
- How might frass help plants in a garden?
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