The School Cafeteria Cooling Problem
A school cafeteria cooks a large batch of beef stew at 1:00 p.m. for the next day's lunch. The stew is placed in a deep 12-inch stockpot and put into a walk-in cooler at 2:00 p.m. The cooler reads 36°F (2°C). At 5:00 p.m., a staff member checks the stew with a probe thermometer and finds the center at 58°F (14°C). The pot is still deep and full. The cafeteria manager says the stew will be fine because the cooler is cold. The next morning, the stew is reheated to 165°F and served. A food handler who has been vomiting since the previous evening is scheduled to work the breakfast shift and says she feels better. The cafeteria also has a salad bar with cut melons and leafy greens.
1. Evaluate the cooling process for the beef stew and determine whether the stew was safely handled.
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The stew was not cooled safely. The standard cooling requirement is to cool food from 135°F to 70°F within 2 hours, and from 70°F to 41°F within an additional 4 hours, for a total of 6 hours. Here, the stew was placed in a deep, full stockpot, which insulates the center and slows cooling. At 5:00 p.m., three hours after it went into the cooler, the center was still 58°F. That means it had not reached 70°F within 2 hours, and it was still above 41°F at the 3-hour mark. The cooler's air temperature being 36°F does not guarantee the food's center cools quickly. The stew should have been divided into shallow pans, left uncovered or loosely covered, and stirred or placed in an ice bath. Because the cooling was too slow, the stew should not have been served the next day even after reheating to 165°F, since heat-stable toxins may already have formed.
2. What should the manager do about the food handler who was vomiting and now says she is better?
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The food handler should not work with food. Vomiting is a symptom of illness that can be spread through food, and a food handler who has been vomiting should be excluded from food handling until symptoms have been gone for at least 24 hours, or as required by local rules and the person's employer. Feeling better the next morning is not enough to rule out shedding of pathogens. The manager should send the handler home or assign non-food duties away from exposed food and clean equipment. The manager should also review whether the handler's illness could be tied to the stew or other food, and should clean and sanitize any surfaces the handler touched. If the handler had a diagnosed infection such as norovirus, Salmonella, Shigella, E. coli O157:H7, or hepatitis A, additional reporting and exclusion rules apply.
3. How should the salad bar be managed given the stew problem and the ill handler?
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The salad bar serves ready-to-eat food, so it deserves extra care. Cut melons and leafy greens should be kept at 41°F or below, checked with a calibrated thermometer, and not left out beyond the time limit. The handler's illness raises the risk of contamination, so any salad-bar items the handler touched or handled should be discarded, and the bar should be cleaned and sanitized. The manager should assign a healthy handler to restock the bar, use clean utensils and gloves, and avoid bare-hand contact with ready-to-eat items. The bar should have sneeze guards, clean plates for returns, and a plan to discard food that has been out too long. The manager should also verify that the salad bar's cold holding is working and record temperatures.