7-3.
TEMPERATURE AND LOSS OF SERVING QUALITY
In addition to disease prevention, temperature control prevents food deterioration
and loss of serving quality. When food temperature is not controlled, deterioration will
be faster. In some cases, food taste and appearance will be changed; this will make the
food unpleasant to eat and result in considerable waste.
7-4.
FOOD PREPARATION AND THE TEMPERATURE DANGER ZONE
Safe temperatures mean 45 F or below and 140 F or above. Any temperature
between 45 F and 140 F is considered to be in the TEMPERATURE DANGER ZONE.
Food products have to be in the danger zone at some time during their preparation.
However, 3 hours is the maximum time that a food can be in the danger zone without
becoming dangerously contaminated. After 3 hours in the danger zone, enough
bacteria can grow to cause foodborne disease outbreaks. Unfortunately, a food does
not have to be in the danger zone for 3 consecutive hours to become a health hazard.
The time accumulates; that is, each separate period which exposes the food to danger
zone temperatures counts toward the 3-hour limit. For example, a frozen food is to be
prepared. First, the food has to be thawed. The thawing period places the food in the
danger zone. Later, the food may be mixed with other food items or chopped or cut.
This again exposes the food to dangerous temperatures. In addition, the food may be
contaminated from contact with other foods or utensils. If the food is left sitting at room
temperature, it once again is in the danger zone. From this example, you can see that it
is very easy for food to stay in the danger zone for 3 hours or more. When inspecting
food preparation procedures at a full-service food facility, you must determine that
personnel are following procedures to minimize the time that potentially hazardous food
items remain in the danger zone.
7-5.
BASIC PRINCIPLES OF FOOD COOLING
a. To be able to determine whether personnel are minimizing the time that a
food spends in the danger zone, you must know the basics of how foods cool.
b. As a general rule, heat is conducted more rapidly through liquid products than
through solid products. This means that solids cool at a slower rate than liquids and
remain in the danger zone for a longer period of time. Due to this, personnel must take
care to cool solid food items as quickly as possible after preparation.
c. Foods that have a high fat or starch content tend to cool slowly. These
products must also be cooled rapidly.
d. Foods with a large surface area cool more rapidly than foods with a small
surface area.
e. Of particular importance is the fact that small, shallow portions of food cool
more rapidly than large, deep portions.
MD0181
7-3