Executive Summary
The use of various types of composts, soil amendments, or growth stimulants is important for the production of fruit and vegetable crops. Composts are created using a wide variety of raw organic materials including animal manures and both “green” and food waste, i.e., materials that have the potential to be contaminated with human pathogens. Therefore, the efficacy of the composting process and manufacture of other types of soil amendments must be conducted so as to control human pathogens that might be present. CPS-funded research has resulted in the following conclusions:
- The manufacture of any type of compost or organic-containing soil amendment is a process, and controls must be in place to ensure optimal pathogen reduction.
- There are multiple process variables for compost manufacture including moisture, heat-up rate, time at lethal temperature, pH, particle size, contact time, the raw materials used to create the compost, and the resident microbial community among others.
- It is important to consider that different pathogens have different sensitivities to temperature when validating compost or soil amendment processing.
- Proper storage and handling post-process is needed to prevent re-contamination.
- Chicken pellet production is a good example of understanding the condition and history of raw materials used to manufacture soil amendments and the differential sensitivities to heat demonstrated by different pathogens.