Madison Chemical introduces MadBrew® STONE ACID, a specially inhibited, low-foam acid blend for the removal of hard water deposits and scale, extract from wort, lipids from hop compounds, and more. This formulation dissolves the crystalline molecular structure of the calcium carbonate which permits the complete removal of the deposits from the kettle, heat exchanger, or other equipment. Ideal for stainless steel and copper alloys when used as directed, MadBrew STONE ACID is recommended for use prior to Enviro-Clean BOIL-OUT on hot side brew house cleaning applications, and in advance of Enviro-Clean BOIL OUT on heat exchangers. It is ideal for craft breweries of all sizes and volumes, as well as food and beverage plants where hard water deposits and scale are problematic.

MadBrew STONE ACID is acceptable for use in food and beverage plants as an A3 compound for use in all departments. This product contains a chemical indicator. If the solution is red-purple sufficient active acid is present; if solution turns yellow or red-purple disappears, the acid is becoming compromised in its ability to continue to dissolve the crystalline structure, and additional MadBrew STONE ACID should be added. 

Recommended dilutions are dependent on factors such as calcium hardness, the composition of the wort extract, and the number of brews between cleanings. Customers typically “dial in” final concentrations after several trails/cleanings. Final concertation of MadBrew STONE ACID dictates the Enviro-Clean BOIL-OUT concentration, as identical concentrations are utilized.

Once the desired dilution is determined, circulate it at 140 °F for 30 to 45 minutes (times may vary depending upon local factors). If solution turns yellow, additional MadBrew STONE ACID must be added to maintain a red-purple color. After draining and rinsing with ambient, potable water, circulate an identical dilution of MadBrew® CAUSTIC-LF along with a 1 percent solution of MadBrew® OX II at 140 °F for 45 minutes. Drain and rinse with ambient potable water, and the equipment should be free of scale and other hard water deposits. 

Before using MadBrew STONE ACID, food products and packaging materials must be removed from the room or carefully protected. After use, all surfaces in the area must be thoroughly rinsed with potable water. 

Standard Operating Procedures may need to be developed for specific concentration and temperature. Madison Chemical Representatives are available to assist.


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