Chlorine Dioxide for the Brewing Industry

SAFRAX Chlorine dioxide technology provides a cost-effective mechanism for brewery sanitation. Chlorine dioxide can be safely generated and provides broad-spectrum control of spoil- age microorganisms. Chlorine dioxide can be applied to many different areas in both the brewing and production areas.

Chlorine dioxide is a safe and effective sanitizer for use in a variety of brewing and packaging applications. Chlorine dioxide can be applied to water systems, processing equipment, and environmental surfaces to reduce or eliminate brewery spoilage organisms.

Chlorine dioxide in water solution provides effective sanitizing for the brewing industry. Chlorine dioxide can be applied in several different areas of the brewery, including cleaning-in-place (CIP) sanitizing of tanks and lines, water treatment, and environmental sanitizing. Chlorine dioxide can also be used for beer packaging, including bottle and cap rinse and sanitizing rinse of fillers and other production equipment.

Description and Properties of Chlorine Dioxide

The molecular structure of chlorine dioxide is ClO2. Chlorine dioxide occurs naturally as a gas. For most brewery sanitizing applications, chlorine dioxide gas is dissolved in water and used as an aqueous solution. Aqueous chlorine dioxide solutions have a yellow to yellow-green color. The color generally corresponds to the concentration.Solutions in the range of 1–5 parts per million (ppm) are a very faint yellow.Concentrated solutions in the range of 500– 1,000 ppm are bright yellow to yellow-green. In the United States, the maximum allowable chlorine dioxide concentration in potable water is 1.0 ppm of residual.Typically, a chlorine dioxide concentration of 5 to 500 ppm is used for hard surface sanitizing.

Advantages of chlorine Dioxide in The Brewry integration

Antimicrobial Activity: Chlorine dioxide is a strong oxidizing agent. It is effective against a variety of beer spoilage organisms, including bacteria, yeast, and mold. Effective control of spoilage bacteria, such as Lactobacillus sp. and Pediococcus sp., on hard surfaces can generally be accomplished with a chlorine dioxide concentration of 50 ppm. Slightly higher concentrations may be required for high levels of yeast.

No Off-Flavors or Taint of Beer: Chlorine dioxide does not impart any taste to beer. It can be applied to surfaces in close proximity to beer production and will not cause off-flavors.

Reduced Corrosion: Since chlorine dioxide is used at lower levels than hypochlorite, it is less corrosive to production equipment.

Reduced costs thanks to minimal use of chemicals: In breweries, expensive chemicals such as peracetic acid, sodium hypochlorite and hydrogen peroxide are often used in very high concentrations for disinfection purposes. By using chlorine dioxide generated on site, both the application concentration and application temperature can be considerably reduced. This results in significantly lower operating costs, as well as the use of cheaper chemicals.

Chlorine dioxide SAFRAX complies with drinking water regulations, so does not need to be fully rinsed out

Brewery Applications

Chlorine dioxide has effectively been applied in many brewery areas, including:

  • CIP sanitizing of tanks and lines
  • Floor and environmental sanitizing
  • Exterior sanitizing of beer fillers
  • Empty bottle rinsing
  • Crown rinsing
  • Pasteurizer rinse zone treatment
  • Conveyor belt sanitizing
  • Incoming water treatment

SAFRAX: Chlorine Dioxide For Brewing

SAFRAX delivers superior sanitation without compromising the integrity or quality of the brewing process.

Micro-contamination can originate from a variety of sources in the brewing process: Raw materials, air, brewing water, additives and even pitching yeast can act as a constant supply of contaminants. These factors can contribute to minor changes in beer flavor and fermentation performance, resulting in flavor and aroma defects.

For brew masters, preventing the growth of these microorganisms has become a top priority. Using chlorine bleach for sanitation and disinfection in these facilities has been linked to TCA production. SAFRAX does not negatively react with phenols to create TCA or TCP.

♦  Tasteless – does not affect the integrity or taste of the product.
♦  Non-Corrosive – will not harm infrastructure and equipment
♦  No harmful by-products
♦  99.9% Kill of Microorganisms
♦  Prevents and removes biofilm
♦  Effective over wide range of pH (4-12)
♦  Cost effective

♦  Final sanitizer when washing equipment and tanks
♦  Process water treatment and sanitizer
♦  Keg and bottle sanitizing

Case Studies

Treatment of Brewing Water


Problem: Brewing water may require chemical treatment to reduce or eliminate microorganisms. Chlorine treatment of brewing water, however, can contribute to off-odors and off-taste. When water is treated with chlorine, a carbon filter is usually installed to remove the chlorine. The carbon filter can then become a breeding ground for microorganisms.

Solution: Dosing about 0.2 ppm of chlorine dioxide into brewing water significantly reduces microorganism fouling, while causing no off-flavors or off-odors in the beer.

Conveyor Treatment


Problem: Conveyors downstream of the can seamer were not treated with conveyor lubricant but with water only, by way of standard lubricant spray nozzles. Microorganism growth was prevalent on the conveyors, leading to buildup of slime and odors. The microorganism odor would transfer to the cans during production. Conveyors were difficult to clean, and significant manual labor and downtime were required to completely clean the belts and supports.

Solution: Dose 1 ppm of chlorine dioxide into the water supply header to the can conveyors, so that 1 ppm of chlorine dioxide is continually supplied to the conveyors. Microorganism counts were significantly reduced, and slime buildup and odors were eliminated. The conveyors looked cleaner and downtime for manual cleaning was significantly reduced.

Crown and Bottle Rinsing


Problem: A small brewery producing unpasteurized beer had problems with microorganism contamination from empty bottles and crowns. Chlorine or iodine spray led to off-odors.

Solution: Application of 0.5-ppm chlorine dioxide spray onto crowns and into empty bottles eliminated microorganism contamination prior to reaching the filler.

Periodic Sanitizing of Filler Exteriors


Problem: Production of nonpasteurized beer required filler shutdown to manually clean and sanitize the filler exterior, crowner, infeed and exit conveyors, and other sensitive production equipment in the filler room. If chlorine or iodine sanitizer were used, excessive surface rinsing was required to eliminate all odors and prevent staining and corrosion.

Solution: Apply 1 to 2 ppm chlorine dioxide solution to the filler every 2 hours. Fixed spray balls and spray nozzles apply sani- tizing solution to all critical areas of the filler. Push-button activation saves time and ensures that the sanitizing cycle is performed consistently. Automatic rinsing saved time and water and ensured complete rinsing. Microorganism counts were significantly reduced and production efficiency increased.