4  SPECIFIC PRINCIPLES TO COVER EXCEPTIONS AND ADDITIONS TO THE DESIGN, CONSTRUCTION AND CLEANING OF ALL BAKERY EQUIPMENT, AS DEFINED IN SECTION 3.

4.20  DESIGN REQUIREMENTS FOR LIQUID FERMENT EQUIPMENT

4.20.1 Definitions

4.20.1.1 Liquid Ferment Equipment is that equipment in which a part of the ingredients for bakery products is fermented in a liquid media.

4.20.1.2 Fermentation Tanks shall include those tanks for products of fermentation whether designed for mixing, holding, aging, cooling or for any other function within a liquid ferment system.

4.20.2 Specific Design Requirements

4.20.2.1 The system shall be designed to facilitate cleaning in place (CIP) or sanitary take-apart. All components of the system shall be constructed to facilitate complete drainage.

4.20.2.2 That portion of the metal used to join the inside tank lining to the outer wall shall be integral with or welded to the inside lining and shall be sloped or so arranged that all drainage will be away from the product zone.

4.20.2.3 Tank bridges shall be pitched to the outside of the tank for complete drainage and shall have a raised rim of at least 3/8 inch (10mm) where edges meet covers. Bridges shall be installed so that the underside is readily accessible from outside the tank.

4.20.2.4 The exterior of processing tanks shall be of corrosion-resistant material.

4.20.2.5 If the lip or edge of a tank, cover or bridge is rolled, the arc of roll shall not exceed 180 degrees, and the returned edge shall be at least ¾ inch (20mm) from the adjacent surfaces.

4.20.2.6 Piping, valves, fittings and heat exchangers shall conform to the applicable 3-A Sanitary Standards.

4.20.2.7 Inlet, agitator shaft, or instrument openings in the cover or bridge to which connections are not permanently attached shall be raised at least 3/8 inch (10mm). Pipelines, agitator shafts, or accessories entering through cover or bridge shall be fitted with a sanitary umbrella that overlaps edges of openings.

4.20.2.8 Discharge openings of the water inlet shall be located at least 1 inch (25mm) or twice the diameter of the inlet pipe, whichever is greater, above the flood level rim.

4.20.2.9 Permanently installed inlet or outlet lines, or instrument wells, through equipment sidewalls, shall be welded. Level sensors installed on bottom or side shell should be flush type to avoid contamination in recessed areas or removable to clean.

4.20.2.10 Agitators permanently mounted are not required to be removable if they do not interfere with drainage from the tank and are readily accessible. If a support in the product zone is necessary for the operation of an agitator, it shall be of a packless bearing type and agitator or support shall be readily accessible or removable.

4.20.2.11 In totally enclosed tanks for the storage of liquid ferment, a hooded air vent of not less than 3 square inches (58cm2) in free open air shall be installed at the top of the tank. The air vent shall be equipped with a perforated screen having openings no greater than 1/16 inch (1.5mm) in diameter, or slots no wider than 1/32 inch (0.8mm). All parts shall be readily accessible and, except for the housing, shall be readily removable.

4.20.2.12 Unless other comparable means of egress are provided, a manhole shall be provided at the drainage end or side of the tank. The dimensions of the manhole opening shall be not less than 15 inches (380mm) vertical and 20 inches (500mm) horizontal, or 18 inches (460mm) in diameter. The cover shall be of the inside-outside swing-type and shall be readily removable.

4.20.2.13 Pumps for liquid ferment shall meet the following requirements:

4.20.2.13.1 Permanently joined surfaces with a total included internal angle less than 135 degrees shall have a radius of not less than 1/32 inch (0.8mm) tangential to both adjacent surfaces.

4.20.2.13.2 Parts forming the space between the motor and the pump body shall be constructed to be readily accessible and drain freely.

4.20.2.13.3 Shaft seals shall be readily removable.

4.20.2.13.4 Either single service gaskets or readily removable multi-use gaskets shall be used.

4.20.2.13.5 Inlets, outlets, and impeller fastenings shall conform to the principles of applicable 3-A Sanitary Standards.

4.20.2.14 Liquid meters for liquid ferment shall conform to the requirements of Section 4.26.

4.20.2.15 Unless sealed to floor, cylindrical tanks standing on end with a diameter greater than 72 inches (1.75 meters) shall have a minimum clearance of 8 inches (200mm) from the floor.

4.20.2.16 For pumps mounted on legs, the legs shall be smooth with round ends and no exposed thread. Legs made of hollow stock shall be sealed. On pumps with legs designed to be fixed to the floor, the minimum clearance between the lowest part of the base and the floor shall be 4 inches (100mm). When a pump is mounted on a base, a minimum clearance of at least 2 inches (50mm) shall be provided between the pump belly and the base. Readily portable pumps not permanently attached shall have leg heights of not less than 2 inches (50mm).

4.20.2.17 All exterior seams of the outer shell of tanks shall be sealed by welding.

4.20.2.18 All equipment, piping, and conduit in the liquid ferment area shall be washed down.