Protein foods that are not served immediately after they are cooked should either be chilled to temperatures of 40F or lower (but not frozen) or held at 140F or higher. Protein foods include meats, fish, poultry, gravies, meat stocks, soups, eggs, custards, cream fillings, and milk. Growth of harmful bacteria and the development of toxins (poisons) formed by the bacteria occur rapidly in cooked protein foods during holding at temperatures between 40F and 140F. Cooked protein foods that have been held at temperatures between 40F and 140F for more than 4 hours will be considered unfit for consumption and must be destroyed.

This principle is known as the 4-hour rule. If the product is refrigerated at intervals and then permitted to warm up, the total time of the various periods between 40F and 140F must not be more than 4 hours. Protein foods composed of ingredients that are hand-peeled, hand-sliced, or hand-diced after they are cooked should never be used as leftovers; the 4-hour limit between temperatures of 40F and 140F is usually taken in preparing, chilling, and serving the food. These foods include potato, chicken, macaroni, shrimp, and egg salads and similar items. Hand preparation not only increases the chance of contamination, but generally increases the length of time that these foods are held at room temperatures. It is also dangerous to return opened jars or bowls of mayonnaise and cooked salad dressing from the salad bar to the refrigerator for reuse at a later meal because of the danger of miscalculation as to the total time that has elapsed from the time that these salad dressings have been held at temperatures between 40F and 140F.

Holding Temperatures

Holding temperatures are of utmost importance. Food held at temperatures that are too high or too low can ruin both the taste and the appearance of food as well as increase the risks of food-borne disease.

HOT FOODS.- The holding temperature of hot foods held on a serving line should be maintained between 180F and 200F.

COLD FOODS.- Keep cold foods such as salads, potato salad combinations, and ham plates cold by setting them on ice or on refrigerated salad bar units maintained between 34F and 40F.

BEVERAGES.- Beverages should be served hot or cold as applicable. As with food, the quality depends on proper preparation, holding, and dispensing. Leftovers

When leftovers or warm foods are chilled, care must be taken to ensure prompt and thorough chilling (40F or below) to the center of the food mass. Foods that are to be refrigerated should be placed in shallow pans to a depth of not more than 3 inches and must be covered with lids or waxed paper. Do not put leftovers in large, deep pans as chilling may take so long to get to the center of the food mass that sufficient time is allowed for the growth of harmful bacteria and development of toxins. Guard against any procedure that might delay cooling. Place foods to be chilled in the chill box immediately. Leftover food must not be saved for more than 36 hours. Freezing of leftovers is prohibited. Foods composed of ingredients that have been peeled, sliced, or diced by hand after cooking must never be used as leftovers since the 4-hour limit between temperatures of 40F and 140F is usually taken up in preparing, chilling, and serving the food. To prevent miscalculations in the length of time leftovers have been stored, all leftovers must be labeled with the date and time of preparation.

Frozen Foods

Frozen foods should be thawed in the refrigerator. Freezing breaks down tissue and, therefore, foods can be invaded by germs more rapidly. Once foods are frozen and then thawed, they must not be refrozen. If not eaten, they should be stored under 40F.

Milk and Milk Products

Milk and milk products and other protein foods are frequent offenders in transmitting infectious diseases to man because of their rapid rate of perishability. Strict surveillance of all handling procedures from cow to man is necessary to prevent contamination and possible milk-borne diseases.

When procured by Navy and Marine Corps activities, milk and milk products must conform in all respects to either federal or military specifications. The perishability of such products is a most important factor, thus strict compliance with all sanitary requirements is mandatory.

Delivery inspections of dairy products are normally conducted by personnel attached to the receiving activities. These inspectors must make sure milk and milk products are from approved sources and delivered in containers that are in good condition and properly sealed. They must make sure the temperature of the product on delivery is 40F or less or follows the current Defense Personnel Support Center (DPSC) contract.

Of prime importance to medical and foodservice personnel is the maintenance of recommended temperatures in storing (40F or less), dispensing (32F-40F), and enforcing approved sanitary methods in the handling of such products.

Fresh Fruits and Vegetables

Fresh fruits and vegetables should be washed thoroughly under running water to remove any particles of dirt or to remove poisonous insect sprays. Green vegetables of uncertain origin should be suspected of being contaminated with pathogenic organisms. They should be chemically sanitized by immersion for at least 15 minutes in a 100-ppm (parts per million) available chlorine solution, or 30 minutes in a 50-ppm available chlorine solution, or other approved method. Then they should be thoroughly rinsed with potable water before they are cooked or served. Head items such as lettuce, cabbage, or celery must be broken apart before they are sanitized.

Canned Products

Canned foods that appear abnormal in odor or appearance should never be eaten or even tasted, but should be discarded. When you are inspecting canned meats, fish, poultry, vegetables, fruit, and juices, the following factors should be considered.

CAN LABELS.- Check to make sure contents and processing date are stamped on the end of the container or on the label.

CAN EXTERIOR.- The exterior of the can should be examined for general appearance, dents, swelling, rust, and pinholes. Cans having severe dents that cross either the side or end seams or that crinkle the metal to a point similar to those depicted figure 1-3, 1-4, and 1-5 should not be used. Rusty cans maybe used provided the rust does not penetrate the can. Rust that can be wiped off is not penetrating.

CAN INTERIOR.- Contents should be removed, the can rinsed, and the interior examined for pinholes against a strong light. If pinholes are present, contents should be discarded.

CONTENTS.- Contents of can should be examined for characteristic odor and appearance of the product.

REJECTION OR SURVEY.- Except for coffee and molasses, foods contained in cans displaying the following conditions are unsatisfactory and should be surveyed and disposed of:

Figure 1-3.-Severe angularly dented can with crimping of body.

Figure 1-4.-Severe dent that buckles end seam of a can.

Figure 1-5.-A severely dented can in which the end seam is pulled out of position.

Pinholes-tiny holes caused by action of food acids during prolonged storage.

Swells (or swellers)-both ends of cans bulge outward because of bacterial action and gas production. Ends do not yield to finger pressure. (Molasses may bulge in tropical areas, but this condition is not dangerous and the product need not be rejected for this reason.)

Springers-one or both ends bulge outward because of bacterial action and gas. However, this bulge will yield on pressure and spring back to bulge condition on release.  Springers or swellers of coffee containers, however, usually indicate a properly sealed container that has merely retained natural coffee-bean gases.

Flippers-both ends are flat, but one end will bulge out ward when the opposite end receives pressure. This condition is caused by either bacterial action or chemical action resulting in gas production.