Mich. Comp. Laws § 288.711: Condensed products; temperature; use of surge, balance, or storage tank.

Sec. 151.

A person may transport to a drying plant condensed skim made from pasteurized skim milk. Condensed skim shall be effectively repasteurized at the drying plant, before drying, at not less than 166°F (75°C) for 15 seconds or the equivalent period in bacterial destruction approved by the department.

A person shall pasteurize all buttermilk or substance from which the cream is derived before condensing at a temperature of 161 °F (72°C) for 15 seconds or the equivalent period in bacterial destruction approved by the department.

A person shall pasteurize all cheese whey or milk from which the cheese whey is derived before condensing at a temperature of 161 °F (72°C) for 15 seconds or the equivalent period in bacterial destruction approved by the department.

A person shall use surge tanks or balance tanks between evaporators and a dryer only to hold the minimum amount of condensed product necessary for a uniform flow to the dryers and shall either ensure each tank holds the condensed product at temperatures specified in section 70 or completely empty and wash each tank after each 4 hours of operation or less. In either case, the person shall provide alternate tanks to permit continuous operation during washing of tanks.

Production of a condensed product that exceeds the amount a dryer will take continuously from pans may be bypassed through a cooler into a storage tank at temperatures specified in section 70 and held at that temperature until a dryer is available.

A person shall make product cut-off points at least every 24 hours and completely empty, wash, and sanitize a storage tank before reusing the tank.