The use of aqueous ozone for cleaning operations in breweries Ozone clean in place in food industries - ozone as an alternative sanitising agent for cleaning operations in food industry

The production of beer is characterized by the consumption of large volumes of fresh water. Whereas, cleaning operations are the highest water consumption demanding activities in breweries. Commonly “Cleaning In Place” (CIP) systems are used in closed processing lines. These consist of automatic cleaning and disinfection programs based on a succession of several solutions of water, cleaning chemicals and disinfection agents. Typical disinfection chemicals are based on Chlorine, other halogens or H2O2. These chemicals are discharged into sewer systems together with large amounts of water necessary to rinse out residual chemicals, which are being questioned for their unhealthy effects on humans. Ozone has the potential to replace these chemicals currently employed in the different CIP processes. Ozone is a powerful broad-spectrum antimicrobial agent that is active against bacteria, fungi, viruses, protozoa, and bacterial and fungal spores, by attacking various cell membrane, walland cell constituents, this is due to the high oxidation potential of ozone (2.07 V) far greater than that of other chemical compounds currently applied for cleaning and disinfection operations in the brewing industry. The European research project OZONECIP, aims to demonstrate the environmental advantages of the use of ozone instead of the conventional chemicals used in “Cleaning In Place” operations in different food processing industries. In order to achieve these objectives a prototype will be designed, built and prepared for assaying CIP processes which will allow obtaining environmental indicators and values for its evaluation. The prototype enables the simulation of industrial CIP processes carried out in breweries (also in diaries and wineries) and essay equivalent processes based in ozone. Key-words: Ozone, cleaning operations, brewing industry, Introduction and current situation in breweries The production of beer is characterized by the consumption of large volumes of fresh water. Breweries use almost all the water consumed for cleaning and disinfection operations, thus becoming wastewater effluents. It has been reported, that a brewery needs about 2.5-6 hl water/hl beer sold (Rüffer and Rosenwinkel 1991). The most important cleaning tasks are related to the washing of process vessels, tanks and the net of pipes that are involved in the production process. Commonly “Cleaning In Place” systems (CIP) are used, these are characterized by automatic cleaning programs based on a succession of several solutions of water, cleaning chemicals and disinfection agents. Typical disinfection chemicals are based on Chlorine, other halogens or H2O2. These chemicals are discharged into sewer systems together with large amounts of water necessary to rinse out residual chemicals, which are being questioned for their unhealthy effects on humans. Current practices for cleaning and disinfection in breweries vary according to the target surface: • Closed equipment: Cleaning In Place processes are the most employed procedure for cleaning and disinfection operation in breweries. It is applied in closed processing lines, such as pipes, vessels and tanks. • Open surfaces: The cleaning and disinfection operations of open surfaces in breweries, such as e.g. fillers or conveyors in the bottling cellar, are usually performed using low-pressure foam systems or thin film cleaning, following the cleaning and disinfection pattern showed in Table 1. The use of hot solutions or strong chemicals is in many cases limited for safety reasons. (Holah, 1992).