ATCP 65.86(3)(c)2.a.a. Determine the performance error of the testing device with respect to each daily performance check sample. The performance error is the difference between the known percentage content of each milk component in that sample, as determined by the sample provider, and the percentage content measured by the testing device.
ATCP 65.86(3)(c)2.b.b. Based on the performance errors for the individual samples under subdivision paragraph a, calculate the mean difference for the set of daily performance check samples. The mean difference is the sum of the performance errors for the individual samples, divided by the number of samples in the set.
ATCP 65.86(3)(c)3.3. If, on a daily performance check under subd. 1., the mean difference calculated under sub. (2) (b) exceeds plus or minus 0.044% for milkfat or protein or plus or minus 0.084% for total solids or solids-not-fat the testing device shall not be used until it is recalibrated under par. (b).
ATCP 65.86(3)(c)4.4. A set of daily performance check samples shall be obtained from a sample provider approved by the division. A set shall consist of at least 5 individual samples, each of which complies with all of the following requirements:
ATCP 65.86(3)(c)4.a.a. Each sample shall be not more than 21 days old.
ATCP 65.86(3)(c)4.b.b. Each sample shall be a fresh milk sample preserved with bronopol (2-bromo-2-nitro-1, 3-propanediol) or another approved preservative. Preservative methods, formulations, and concentrations shall be approved by the department.
ATCP 65.86(3)(c)4.c.c. Each sample shall have a known percentage content of each relevant milk component, determined by the sample provider under pars. (e) to (h).
ATCP 65.86(3)(d)(d) Reference checks.
ATCP 65.86(3)(d)1.1. If an automated testing device is used to test for milkfat, protein, total solids, or solids-not-fat in milk, and if the test results may affect the price paid to a milk producer, that device shall be subjected to a daily reference check under subd. 2 and hourly reference checks under subd. 3.
ATCP 65.86(3)(d)2.2. A daily reference check required under subd. 1 shall be done in accordance with all of the following requirements:
ATCP 65.86(3)(d)2.a.a. A daily reference check shall be conducted before each day’s testing, at the same time that the dairy plant operator conducts the daily performance check under par. (c). The daily reference check shall be conducted, for each relevant milk component by a tester who is licensed under s. 97.17 or 98.145, Stats., to operate the testing device.
ATCP 65.86(3)(d)2.b.b. To perform a daily reference check, a tester shall perform 10 tests on a reference sample. The reference sample may be a homogenized milk sample prepared by the dairy plant operator, or it may be a daily performance check sample obtained from a sample provider approved by the department under par. (c) 4. The 10 test results shall be averaged and the average result shall be used as a comparison value for the hourly reference checks under subd. 3.
ATCP 65.86(3)(d)3.3. An hourly reference check required under subd. 1 shall be done in accordance with all of the following requirements:
ATCP 65.86(3)(d)3.a.a. An hourly reference check shall be conducted for each milk component before each hour’s testing for that component. To conduct an hourly reference check, a tester shall test the same reference sample used for the daily reference check under subd. 2.
ATCP 65.86(3)(d)3.b.b. For each relevant milk component the hourly reference check result shall be compared to the average result obtained on the daily reference check under subd. 2. If an hourly reference check result differs from the average result on the daily reference check by more than 0.034% for milkfat or protein or 0.064% for total solids or solids-not-fat, the testing device shall not be used until the condition causing the difference is found and corrected. Test results obtained before the device is corrected, and after the last previous conforming reference check, shall not be used in determining the amount paid to milk producers.
ATCP 65.86(3)(e)(e) Calibration and daily performance check samples; milkfat contents.
ATCP 65.86(3)(e)1.1. The provider of a calibration sample under par. (b) or a daily performance check sample under par. (c) shall determine the known percentage content of milkfat in that sample by averaging the results of 3 milkfat tests using a method specified under subd. 4. The percentage milkfat results from those 3 milkfat tests shall not vary by more than 0.034 percentage points.
ATCP 65.86(3)(e)2.2. The known milkfat content of a calibration sample, expressed as a percentage of the sample weight, shall be at least 2.5%. Within a set of calibration samples, the difference in known milkfat content between the lowest milkfat sample and the highest milkfat sample, expressed as a percentage of average sample weight, shall be at least 2.5%.
ATCP 65.86(3)(e)3.3. The known milkfat content of a daily performance check sample, expressed as a percentage of the sample weight, shall be at least 2.8%. Within a set of daily performance check samples, the difference in known milkfat content between the lowest milkfat sample and the highest milkfat sample, expressed as a percentage of average sample weight, shall be at least 1.5%.
ATCP 65.86(3)(e)4.4. To determine the milkfat content of a calibration sample or daily performance check sample, the sample provider shall use either a manual or robotic version of the Modified Mojonnier method as described in the ”Official Methods of Analysis of AOAC International,” 18th edition (2005), section 989.05.
ATCP 65.86 NoteNote: The “Official Methods of Analysis of AOAC International,” 18th edition (2005), is on file with the division and the legislative reference bureau, and may be obtained from AOAC International, 2275 Research Blvd., Rockville, MD 20850, website https://www.aoac.org .
ATCP 65.86(3)(f)(f) Calibration and daily performance check samples; protein contents.
ATCP 65.86(3)(f)1.1. The provider of a calibration sample under par. (b) or a daily performance check sample under par. (c) shall determine the known percentage content of protein in that sample by averaging the results of 3 protein tests using the method specified under subd. 3. The percentage protein results from those 3 tests shall not vary by more than 0.034 percentage points.
ATCP 65.86(3)(f)2.2. The known protein content of a calibration or daily performance check sample, expressed as a percentage of sample weight, shall be at least 2.7%. Within a set of calibration samples, the difference in known protein content between the lowest protein sample and the highest protein sample, expressed as a percentage of average sample weight, shall be at least 0.7%. Within a set of daily performance check samples, the difference in known protein content between the lowest protein sample and the highest protein sample, expressed as a percentage of average sample weight, shall be at least 0.5%.
ATCP 65.86(3)(f)3.3. To determine the protein content of a calibration sample or daily performance check sample, the sample provider shall use the traditional or block digester/steam distillation Kjeldahl method as described in the “Official Methods of Analysis of AOAC International,” 18th edition (2005), section 991.20.
ATCP 65.86 NoteNote: The “Official Methods of Analysis of AOAC International,” 18th edition (2005), is on file with the division and the legislative reference bureau, and may be obtained from AOAC International, 2275 Research Blvd., Rockville, MD 20850, website https://www.aoac.org .
ATCP 65.86(3)(g)(g) Calibration and daily performance check samples; total solids.
ATCP 65.86(3)(g)1.1. The provider of a calibration sample under par. (b) or a daily performance check sample under par. (c) shall determine the known percentage content of total solids in that sample by averaging the results of 3 total solids tests using the method specified under subd. 3. The percentage total solids results from those 3 tests shall not vary by more than 0.054 percentage points.
ATCP 65.86(3)(g)2.2. The known total solids content of a calibration or daily performance check sample, expressed as a percentage of sample weight, shall be at least 11%. Within a set of calibration samples, the difference in known total solids content between the lowest total solids sample and the highest total solids sample, expressed as a percentage of average sample weight, shall be at least 2.00%. Within a set of daily performance check samples, the difference in known total solids content between the lowest total solids sample and the highest total solids sample, expressed as a percentage of average sample weight, shall be at least 1.5%.