The thesis was prepared for Spirax Oy which is responsible for importing and selling products, services and solutions of parent company Spirax-Sarco Engineering plc. Steam is an important medium for heat transfer in food and beverage industry. Due to its unique properties steam can be used in so-called direct steam applications in which steam becomes in contact with food or with a surface used to produce food. High level of steam purity is essential in these processes to avoid compromising of food safety and to keep product quality at expected level.

Purpose of the thesis was to collect a comprehensive set of scientific information in Finnish about circumstances, legislation and available technical solutions regarding the direct steam supply to food. Main focus was to sort out factors affecting steam purity and methods to prevent impurities in steam. According to current legislation the food manufacturer is responsible for safety of the produced food. Ensuring the safety and high quality of the food is based on self-monitoring. Typical ways to approach safety of direct steam supply processes and following the steam purity used were examined with help of quantitative research. Online survey was used as a main tool.

Frequently used practices to monitor and ensure steam purity in direct steam processes of Finnish food & beverage industry were defined based on survey results. The conclusion seems to be bipolarized: the requirements stated in legislation and official guidance are fulfilled comprehensively but preventing the remaining threats that fall on manufacturers’ responsibility may have room for improvement. Development needs vary from plant to plant.

Based on the study there is room for improvement in food & beverage manufacturers’ ability to spot and prevent impurities in steam that comes in direct contact with food. Some of the plants that responded to the survey appear to have very limited ability to ensure the safety of the steam used in direct steam applications. The information gathered to the thesis may be utilized to improve risk assessments related to direct steam applications. Once the level of risk assessments is improved better practices to prevent impurities in steam may take place. If steam is free from impurities both food safety and quality are improved.