# Mushroom Substrate Steam Pasteurization

Source: [https://www.stilsan.com/en/solutions/mantar-substrati-pastorizasyonu-icin-buhar-jeneratoru](https://www.stilsan.com/en/solutions/mantar-substrati-pastorizasyonu-icin-buhar-jeneratoru)

Steam heat treatment of bagged or bulk mushroom substrate in a room or chamber at controlled temperature and duration.

## Process requirements

In mushroom production, substrate preparation and pasteurization or sterilization are not the same step. The target temperature, holding time and cooling arrangement vary according to the mushroom species, substrate recipe and the facility’s cultivation protocol. The objective is to apply the selected protocol in a traceable manner, including at the coldest point of the room.

## How does the solution work?

Steam generated in the generator is delivered to the room or chamber through the distribution line. At the beginning, controlled air removal, steam circulation between the racks and bags, condensate drainage and monitoring of multiple temperature points are required. Time counting should be started according to the reference temperature defined by the process, not only the room air temperature.

- Bag, rack or bulk substrate placement
- In-room distribution and temperature monitoring at the coldest point
- Holding, controlled cooling and a plan to prevent recontamination

## Information required to determine the correct capacity

The net room volume, total substrate mass and initial temperature, the number and arrangement of bags, the target temperature-duration protocol, wall insulation, door use, cycle frequency and ambient conditions are required. A reliable generator cannot be selected based only on square metres or the number of bags.

## Stilsan’s approach and project scope

Stilsan pre-dimensions the steam source, line and control requirements according to the shared protocol. Room construction, racks, fan circulation, sensors and hygiene responsibilities are specified separately in the quotation. Microbiological results or product yield are not guaranteed without a validated cultivation protocol and on-site measurements.

## Frequently asked questions

**Are pasteurization and sterilization the same thing?**

No. The target temperature, duration, pressure and expected microbiological outcome are different. The required process should be determined by the mushroom species, substrate and production protocol.

**Can capacity be selected based on the number of bags?**

The number of bags is an important input but is not sufficient. The total substrate mass, initial temperature, placement, room insulation, target cycle and door use are also required.

**Is a single thermometer sufficient inside the room?**

Temperature distribution may vary in large or densely loaded rooms. Depending on the protocol, multiple measurement points should be considered, with particular attention to the coldest area.

**Can a generator be added to an existing pasteurization room?**

This can be technically evaluated after reviewing the room insulation, distribution line, drainage, air exhaust and control infrastructure.

## Technical sources

1. FAO. [Mushroom Cultivation Guide: Pasteurizing Bags](https://www.fao.org/4/AB497E/ab497e07.htm)
2. FAO AGRIS. [Inactivation of Human Pathogens during Phase II Composting of Mushroom Growth Substrate](https://agris.fao.org/search/en/records/65de516a0f3e94b9e5cd653d)

## Related products

- [Steam Machine](https://www.stilsan.com/en/products/buhar-makinesi): STL-001
- [Steam Machine (Custom Size)](https://www.stilsan.com/en/products/buhar-makinesi-ozel-boyut): STL-002
- [ST-1 Steam Generator](https://www.stilsan.com/en/products/st-1-buhar-jeneratoru): ST-1
- [ST-2 Steam Generator](https://www.stilsan.com/en/products/st-2-buhar-jeneratoru): ST-2

## Related technical guide

[How to Pasteurize Mushroom Substrate with Steam](https://www.stilsan.com/en/blog/mantar-substrati-buharla-pastorizasyon)