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SOPs for Cellar Tank and Equipment Cleaning 6
Cellar work is approximately evenly split between performing a process operation and the cleaning and sanitizing of the equipment used. Hygienically designed stainless steel tanks and equipment are relatively easy to keep clean and sanitized. This, along with advances in cleaning detergent and sanitizer chemicals, has allowed craft breweries to avoid microbial contamination without the use of sterile filtration and pasteurization and still maintain a respectable shelf life for their products. Constructing SOPs designed to use the appropriate cleaning equipment, temperatures, mechanical application, contact time, and concentrations of detergent and sanitizer chemicals and then carefully following the procedural instructions are fundamental to preventing contamination and will save the brewery from dumping bad-tasting beer.
The 24-hour rule for cellar tank and equipment cleaning is recommended best practice:
Cellar tanks, piping, hoses, and equipment should be cleaned within 24 hours after emptying or use and within 24 hours prior to reuse. Depending on the turnaround time, this may be a single cleaning. Sanitizing should occur within 4 hours of wort or beer contact.
For all cleaning and sanitizing SOPs, reference the most current cleaning and sanitizing schedule (see Appendix 4 for an example) for the correct chemicals, temperatures, concentrations, and contact times. As with brewhouse tank cleaning, all final rinses in cellar clean in place (CIP) procedures must be within a pH of 6–8 unless otherwise noted.
SOP Title: Cleaning and Sanitizing Fermenters
SOP Number: 6001-01
Approval: Pending Issue Date: To be determined
Description and Goal of the Procedure:
All tanks and equipment on the cold cellar side of the operation must be both cleaned and sanitized prior to use so the wort or beer won’t pick up spoilage
microbes. The FV tanks are especially critical because they receive cooled, aerated wort from the brewhouse that is ripe for the growth of just about any wort or beer spoilage bacteria or yeast.
Fermenters typically carry the heaviest soiling after emptying, while bright beer and serving tanks show the lightest soiling. Alkaline detergents are used every time an FV tank is washed. An acid cleaning can be conducted after the alkaline wash to reduce mineral deposits and can include an oxidizer to help reduce protein deposits. The acid CIP schedule depends on your local water chemistry. Harder water will require more frequent acid cycles.
Note: Cellar tanks must be completely ventilated prior to a caustic CIP, or a reaction may occur that can implode the tank and cause irreparable damage!
The sanitizing step, using a no-rinse chemical sanitizer on the internal surfaces, will keep microbial loading down and takes place after the CIP and within 4 hours of filling the tank.
Notes:
1. Always use personal protective equipment (PPE) to protect your eyes, hands, and feet!
2. Always add chemicals to water—never add water to chemicals!
Hygiene and Safety Requirements:
1. Food Safety:
a. Always start by washing your hands and removing jewelry. Wear a hat and a beard net if needed.
b. Follow the GMP and hygiene requirements listed in SOP 1001.
2. Personal Safety:
a. PPE: Wear safety goggles, nitrile gloves, and water-resistant shoes or boots.
b. Follow confined space and lockout-tagout procedures for tank entry.
Tools and Equipment Needed:
1. Utility tank to serve as a chemical mixing tank and reservoir (or use the FV tank itself)
2. Air blower with ducting hose for tank ventilation
3. CIP cart pump capable of 3,600 rpm
4. One valve, hoses, tri-clamps, and gaskets
5. Cleaning chemicals; caustic or noncaustic alkaline detergent and/or acid detergent with periodic oxidizer additive and the appropriate titration kits
6. No-rinse sanitizer, such as peroxyacetic acid (PAA), along with a titration kit
7. Warm manual cleaning detergent solution in a dedicated labeled bucket and plastic brushes to clean parts and gaskets; never use abrasive pads
8. Flashlight, ATP swab and meter (if available)
9. Rinse-check pH meter or litmus paper; phenolphthalein indicator for caustic CIP rinse check
Set-Up Steps:
1. Set the tank glycol control valve to 95° C (200° F) to keep the cooling from coming on during the CIP.
2. Crack open the tank vent valve and depressurize the tank. Ideally, the gas will be discharged out of the building. Open the vent valve to fully depressurize the tank, and keep this valve open during the CIP.
3. Open the access door, insert the air blower ducting hose inside, and energize to completely ventilate the tank.
4. Add manual detergent to half a bucket of warm water per the cleaning and sanitizing schedule.
5. Mix the required concentration of caustic solution in the utility tank, depending on the tank size, by adding the amount of chemical specified on the cleaning and sanitizing schedule to warm water. If a utility tank isn’t being used, then wait until the FV tank to be cleaned is prerinsed and mix up the solution inside the tank itself (belly cleaning).
Note: Always add chemicals to water, never water to chemicals!
Operational Steps:
1. After the tank is ventilated, proceed to the next steps.
2. Remove any clamped-on fittings such as the sample valve, thermowell fitting, racking arm fittings, and blow-off hose. Rinse them off and then place (don’t toss!) them, along with clamps and gaskets, into a manual scrub bucket to soak.
3. If the tank has a side access door:
a. Open it, remove the door gasket, rinse and manually scrub both the door and the door gasket, then rerinse.
b. Drape the door gasket around the center door lock handle. Loosely close the door inside the tank opening, but don’t lock it down. This will keep the CIP solution from spraying out, help vent the tank, and avoid vacuum issues.
4. If the tank has a top access door, keep it closed and locked down for the CIP.
5. Leave any fittings on top of the tank, such as the pressure relief valve (PRV), rupture disc, or dry hop port cap or valve, clamped in place during the CIP spray ball recirculation.
6. Burst rinse (5 seconds with the valve open full while draining) to reduce the rough soiling inside the FV tank and to gradually warm it up.
a. Rinse first with ambient city water. Then, if you have a temperature blender, mix in hot water over a series of burst rinses until the temperature reaches that of the CIP detergent solution. Do not overheat!
b. If you don’t have a temperature blender on your water supply, then after the ambient city water rinses, use the utility tank to pump in a 50–50 ratio of hot and cold water.
Note: Avoid rinsing the FV tank with very hot water, or you’ll cause a rapid expansion of the metal, which can weaken weld joints and send hot steam erupting from the tank.
c. Keep the bottom inlet/outlet valve open to drain the burst rinses out to the floor.
7. Pump the chemical solution from the utility tank into the tank to be cleaned through the FV tank outlet piping using hoses from the cart pump outlet. This will clean the outlet piping. If no utility tank is used, then mix the detergent solution in the tank to be cleaned.
8. Once the solution is in the tank, connect the CIP pump outlet hose to a valve, and connect the valve to the CIP arm valve. Use the hinge tap method to tighten all tri-clamp connections. Open both valves. See Appendix 7, Figure A7.3, for a drawing of the completed tank CIP set-up.
9. Once the solution is in the tank, connect the tank inlet/outlet valve to the pump inlet, and recirculate the caustic solution through the CIP spray device for 30 minutes, setting the pump flow as high as possible without any cavitating (the sound of crushing rocks in the pump).
10. While the tank circulates, hand clean the FV tank’s fittings and gaskets in the scrub bucket. Use a round brush to scrub out the tank nozzles where the sample valve and other fittings attach to the tank.
11. If there is a racking arm, then rinse and clean its outside surface and place it loosely back in the tank but don’t clamp it.
12. Once the main circulation is complete, inspect with a flashlight for cleanliness. Restart the circulation if necessary.
13. Recirculate the cleaning solution through the vent arm and racking arm for 5 minutes each, then pump through the blow-off hose into the tank for a minute or two at a low pump speed.
14. Take off any top fittings, such as the PRV or dry hop port cap or valve, to clean manually, rinse, and reinstall (make sure a hop port valve is closed).
15. If a top access door is present, inspect it to ensure it was cleaned, along with its gasket, during CIP spray ball circulation. If not, remove the gasket, rinse off the interior door surface, rinse, and scrub with the manual detergent solution. Rerinse the door along with the gasket. Reinstall the gasket and close and lock down the door.
16. Once the recirculations are completed, pump the solution back into the utility tank or, if this was a belly clean, to the next tank to be cleaned, or let it drain to the floor.
17. Rinse the tank, nozzles, racking, and vent arm with warmed city water burst rinses, letting the water drain to the floor.
Note: Do not rinse a hot FV tank with very cold water, as a vacuum may develop that can damage the tank!
18. Test the final rinse pH to ensure all chemical residue is eliminated. The pH should be between 6 and 8 or result in a colorless phenolphthalein sample.
19. If the tank is to be acid cleaned, mix up an acid detergent solution according to the cleaning and sanitizing schedule, repeat steps 8–18, and rinse to a pH of 6–8. Phenolphthalein cannot be used as a pH indicator for acid CIP rinses.
20. Once the tank has been rinsed down to city water temperature and passes the rinse-water pH test, you can verify that it’s clean with visual inspection and ATP swabs (if possible). Reattach all fittings and gaskets, and close up the tank until it’s ready for sanitizing and use or recleaning.
21. To sanitize the tank, mix up a solution of no-rinse sanitizer in the utility tank or FV tank bottom.
22. If using the utility tank, then pump and recirculate the sanitizer through the CIP arm for at least 10 minutes and through the vent arm and racking arm for 5 minutes each. When complete, drain the solution to the floor. If sanitizing the tank bottom, recirculate the solution using the same contact application times for the CIP arm and fittings and then drain to the floor.
23. The tank is sanitized and ready to fill within 4 hours; resanitize if there is a delay.
Follow-Up Steps:
1. Clean and rinse off the exterior of the tank and the floor area.
2. Mark the tank with the cleaning time, the date, and the rinse pH using chalk.
3. Detach the hoses and drape to dry. Return any clamps or gaskets. Rinse out the scrub buckets and brushes and put them away.
4. Close the bottom tank inlet/outlet valve, the racking arm valves, and the CIP valve, but leave the vent arm valve open.
Quality Checks Required:
1. Titrate the chemicals to ensure they are the correct concentration and adjust as needed.
2. Make sure to check caustic and acid detergent rinses for a pH between 6 and 8.
Documentation Required:
1. Mark the tank in chalk with the cleaning time and date and the rinse-water pH.
■ SOP Title: Caustic Cleaning and Sanitizing Bright Beer and Serving Tanks
SOP Number: 6002-01
Approval: Pending
Issue Date: To be determined
Description and Goal of the Procedure:
Bright beer (BB) and serving tanks normally have the lightest soil loads after use in the brewery. BB tanks can be cleaned with an acid detergent cycle at least weekly and incorporate a periodic caustic detergent cycle. Serving tanks should be cleaned each time they are emptied with a caustic detergent cycle and periodic acid detergent cycles.
This SOP is for the caustic cleaning cycle.
Note: Both serving tanks and BB tanks have a CO2 atmosphere that must be ventilated away before a caustic detergent CIP is started. Failure to adequately ventilate the tank may result in a chemical reaction that can implode the tank, causing irreparable damage.
Always check that the final rinse of the equipment has a pH of 6–8 to ensure there is no chemical carryover.
The sanitizing step, using a no-rinse chemical sanitizer such as PAA on the internal surfaces, keeps microbial loading down and is done after the CIP and within 4 hours of filling the tank. Reference the current cleaning and sanitizing schedule for the correct chemicals, temperatures, concentrations, and contact times.
Note: Always add chemicals to water, never water to chemicals!
Hygiene and Safety Requirements:
1. Food Safety:
a. Always start by washing your hands and removing jewelry. Wear a hat and a beard net if needed.
b. Follow the GMP and hygiene requirements listed in SOP 1001.
2. Personal Safety:
a. PPE: Wear safety goggles, nitrile gloves, and water-resistant shoes or boots.
b. Follow confined space and lockout-tagout procedures for tank entry.
Tools and Equipment Needed:
1. Depressurizing hose
2. Air blower with ducting hose for tank ventilation
3. Utility tank to serve as a chemical mixing tank and reservoir, or use the tank itself (“belly clean”)
4. CIP cart pump