Aerating Compost Impact on pH and Volatile Acids

Blowing air into our food waste compost dramatically impacts the microbial community, the pH, and the organic acids. I measure organic acids and pH changes with and without aeration during food waste composting. Its not new information, and it does help explain how we can manage and minimize odour during the composting process!

[@SobieRobie]

Thanks for the data. BTW we just started this years first heap in our garden and after 3 days it reach 69C!

[@JohnPaul-vs8gx]

Awesome! Congratulations!

[@Abalkacem]

I alaways appreciate informations you give us! Thanks John ❤

[@JohnPaul-vs8gx]

You are welcome!

[@organicentourage]

In a previous video, you mentioned having a pH issue with food waste that you were keeping around 20% and still had a pH issue. We don't process food waste on the farm, but I'm curious. Do you just blow the piles harder or will the 20% O2 level raise the pH over time? Thanks for the instructive videos😀

[@TransformCompost]

With low pH food waste, we have an interesting situation. Usually the food waste has been sitting around for a long time. Its anaerobic which means that the dominant microbial community consists of acid formers, which produce acids that lower the pH. So, when we receive this material, we are trying to change the microbial community to an aerobic microbial community that will no longer produce acids, but also consume the organic acids that are there. We do this by providing lots of oxygen, but also mixing the food waste with bulking agent containing the aerobic microbes that we are trying to encourage! As you observe, most farm wastes do not result in low pH issues.