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STANDARD OPERATING PROCEDURE

Ice Cream MachineModel: 40 BLT

Manufacturer: Emery Thompson Machine & Supply Company

Location: Wet Processing Pilot Plant, 1091 Food Sciences Building

Publication Date: 07/23/2014

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Description and Uses

An ice cream machine is a tool used to make small batches of ice cream. Typically, desired ice cream formulations are mixed by electric mixers, then poured into the ice cream maker’s freezer compartment. The ice cream maker simultaneously freezes the mixture while churning it to aid in its aeration.

Power Specifications

Motor: Model 40 BLT

Power: 5 HP (Compressor), 5 HP (Freezer)

Voltage/Amperage: 220V/37.5A

Phase/Frequency: 3-Phase/60 Hz.

Potential Hazards and Safety Precautions

High Voltage (220V)/Possible Electric Shock

• Make certain to use the correct outlet that is specifically designed to fit the electrical cord plug.

• Make sure the area around the outlet, floor and your hands are completely dry when plugging or unplugging the electrical cord to/from the outlet.

Moving Parts and Pinch Points/Possible Entanglement of Extremities, Hair, Jewelry or Clothing

• The jet cooker operates with moving parts that can create possible pinch points. Keep extremities (especially hands), hair, jewelry and clothing clear of all moving parts while the cooker is in operation.

• Make sure to secure long hair and any loose clothing or jewelry before operating the jet cooker.

Cold Surfaces and Temperatures/Possible Freezer Burns to Exposed Skin

• The ice cream maker operates at very cold temperatures. Keep hands and exposed skin clear of frozen components to avoid freezer burns. Wear thermal-resistant gloves to protect your hands.

Required Personal Protective Equipment

Safety Glasses/Goggles

Protective Footwear (No Open-toed Shoes)

Lab Coat

Thermal-resistant Gloves

Hair Net

Long Pants & Long Sleeves

Tie Back Long Hair

No Loose Fitting Clothing

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Training

Required Training

*Denotes courses offered online

Fire Safety & Extinguisher Training*

Laboratory Safety: Core Concepts*

Machine & Site Specific Training

Recommended Training for Frequent Users

Electrical Safety & Lockout/Tagout

Laboratory Safety: Spill Procedures

Operation

1. Be sure to acquire all required training before operating the ice cream maker. Operation requires machine and site-specific training by the plant plant manager.

2. Before operating the ice cream maker, be sure to read and familiarize yourself with the operator’s manual available in the plant plant manager’s office, 1955 Food Sciences Building.

3. Be sure to wear all required personal protective equipment.

4. During the machine’s operation, be sure to report any problems to the plant plant manager.

5. Electricity to the compressor should be on at all times. The compressor starts and stops automatically by internal pressure controls. It must be able to start and pump away excessive refrigerant pressures caused by heat sterilizing and washing.

6. On water-cooled machines, connect inlet water lines to a chilled water valve.

7. One hour prior to operation, sanitize your machine, utensils and containers (if metal). Keeping cleaned containers covered in a hardening cabinet is recommended as warm containers can cause ice cream melt down (with paper containers, this is not necessary).

8. When ready to begin making ice cream, pour the ice cream mix into the machine’s freezer compartment (cool mix is desirable as it freezes faster). Note: The amount of mix equals one-half its frozen capacity, so plan accordingly.

9. Start the agitator motor.

10. Turn ON the refrigeration.

11. Add flavor in proportion to the volume desired. Fruit and nuts are added later in the batch in order to keep the pieces as large as possible. Freeze vanilla first, followed by stronger flavors in progression to help keep freezer rinses to a minimum.

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12. When ice cream reaches approximately 24°F (depending on the type of mix), turn OFF the refrigeration, but let the agitator motor run an additional minute to provide some whipping action that will help aerate the ice cream. Hint: You can tell when the ice cream has reached its proper temperature by drawing a sample cup. It will have lost its shiny gloss, be firm, and not run when the cup is turned on its side.

Clean-up Procedures

1. After completing the last batch (or at the end of each production day), prepare for clean up by turning OFF the agitator motor and adding cold water into the freezer compartment. Note: Do not turn off wall switch to the freezer, as the compressor will need to occasionally cycle to maintain proper pressures in the system.

2. Turn ON the agitator for a few moments and allow the water to mix inside the freezer.

3. Turn OFF the agitator and drain the rinse water out of the freezer compartment.

4. Add hot water with an approved cleaning compound into the freezer compartment. Then, turn ON the agitator motor for a few moments and allow the hot water and cleaning agent to mix inside the freezer.

5. Turn OFF the agitator and drain the hot water mixture out of the freezer compartment.

6. Once the compartment is clean, open the machine’s front access door to remove the dasher and center shaft.

7. Clean the dasher and center shaft with hot water and an approved cleaning agent in a nearby sink.

8. Before reinstalling the center shaft, confer with the plant plant manager for instructions on how to lubricate the shaft with a tasteless approved lubricant and sanitary gel.

9. After cleaning the machine and work area, and reinstalling the clean dasher and lubricated center shaft, initiate check-out procedures by having the machine and work area inspected by the plant plant manager.

Machine Care and Maintenance

• Inspect the machine after every use for any leakage or broken parts. Report any leak or broken parts to the plant plant manager. All final inspections are performed by the plant plant manager.

• Motors and moving parts should be properly lubricated on a regular basis by the plant plant manager or a service technician.

Accessories

None