Mathematics

Better Cheddar Case Study

You are employed by a small artisan cheese company in their quality assurance team. They have been having trouble with the Cheddar cheese line. Some of the cheeses have significant flavor and texture defects and the company is not sure why. They are careful about sanitation and they have confirmed that microbial contamination (e.g. spoilage bacteria, molds, yeast) is not the cause of the defects. The quality assurance team has tested cheese samples over several weeks and identified a potential cause of the flavor and texture defects. They think that the cheddaring and pressing processes may not be expelling enough whey from the curd. The excess whey left in the curd results in a cheese with a moisture content that is higher than expected. In addition, the flavor and texture defects identified by the sensory group are typical of those present in cheese that has undergone insufficient pressing and contains excessive whey. You have gathered moisture content data for 30 batches of cheese. The data are shown below. The company wants their cheese to have an average moisture content of 37% and will allow a maximum deviation of 0.3% above or below this average.

Sample Set
Moisture Content (%)
Standard Deviation (%) 1 36.91 0.07 2 37.00 0.07 3 37.18 0.08 4 36.90 0.10 5 36.96 0.12 6 37.13 0.12 7 37.12 0.11 8 37.10 0.10 9 37.18 0.09 10 36.96 0.09 11 36.98 0.10 12 37.18 0.08 13 36.96 0.10 14 37.18 0.11 15 37.04 0.09 16 37.17 0.11 17 37.12 0.09 18 37.15 0.07 19 36.95 0.11 20 36.93 0.07 21 36.96 0.10 22 37.03 0.11 23 36.97 0.08 24 37.01 0.07 25 36.96 0.08 26 37.17 0.10 27 37.01 0.09 28 37.18 0.08 29 37.19 0.10 30 37.06 0.11

Note that these data are also provided in a separate Excel sheet