Skippy Foods is recalling thousands of pounds of Skippy peanut butter because of stainless steel fragments possibly contaminating “a limited number of jars.” Clearly, the quality control department did not find the fragments in the jars that they inspected. While this is unfortunate, your Statistical Process Control chapter (Supplement 6) indicates that this can happen and describes the failure as a Type II error where a bad lot passes inspection but is accepted.
Of course, placing the peanut butter in jars is only one step in the peanut butter supply chain. The supply chain for peanut butter is very similar to the supply chain for soft drinks described in Figure 1.2 of your Heizer/Render/Munson textbook.
Farmer: Peanuts are planted in spring, 4 to 5 months later are delivered to warehouses for cleaning, shelled, graded for size, shipped to peanut butter manufacturers
Producer: Peanuts are dry roasted, removed from heat, skins are removed. Nuts are screened and inspected. Peanuts are ground and converted to peanut butter
Packaging: Peanut butter is packed
Distribution: Peanut butter goes to distributor
Sales: Peanut butter goes to retail outlets
Quality control is a part of each of the steps listed above. The peanut butter must meet standards maintained by the U.S. Department of Agriculture and the Food and Drug Administration and the peanut butter is graded by the USDA as Grade A or Fancy, Grade B or Choice or substandard. The grade is a weighted average of color, consistency, absence of defects and flavor and aromas
As is the case with many production operations, the processes yield byproducts. While peanuts are grown mainly as food or for their oil, after harvesting there are leaves, stalks, vines and pods that remain in the field. This residue has high nutritional value and is used as animal feed for assorted livestock. The peanut shells that are a byproduct of the shelling plant are used in the manufacturing of several products and also can be used as compost, mulch, kitty litter or used in fireplaces. Peanut shells can also be used in place of salt on icy sidewalks. And, of course, real peanut shells can be used as packing material in lieu of styrofoam peanut shells.
Classroom Discussion Questions:
- Cite another product that produces byproducts during production.
- What other nuts are commonly turned into nut butter?