Fish and Shellfish The Fish and Wildlife Act provides for USDC inspection of processed fish and shellfish products. All such products prepared in the United States and purchased for enlisted dining facilities originate from plants under the super- vision of the National Maritime Fisheries Service and are marked with the USDC stamp (fig. 5-1).
Each container of unshucked shell stock will be identified by an attached tag that states the name of the shell stock shipper, the kind and quantity of shell stock, and the official certificate number issued according to the law of the jurisdiction. Fresh and frozen shucked shell stock will be packed in nonreturnable containers and marked with the name and address of the shipper, packer, and shucker, and the official certificate number. Make sure shellfish is kept in the original container until use.
Check all fish carefully. Refrozen fish will not be used. Fish that has been refrozen will be soft and discolored and have a sour odor; the wrapping paper may be moist, slimy, or dis- colored and the bottom of the box distorted.
Fresh fish have bright red gills, prominent clear eyes, and firm elastic flesh. Stale fish are dull in appearance, have cloudy and red-bordered eyes and soft flesh. Finger impressions are easily made and will remain when pressure is released. Fish caught over the side at sea will not be used unless there is absolute certainty that they are not poisonous, since cooking does not destroy the poisonous alkaloid in fish.
Fresh crustaceans must be alive to be accept- able. When inspecting crab, lobster, or shrimp, organoleptical procedures (testing with the senses) must be used to determine fitness for human consumption.
Inspect fresh fruits and vegetables upon receipt for wholesomeness. The inspection is based upon USDA standards. Minimum require- ments for the various grades are defined in the Manual of Naval Preventive Medicine, chapter 1.
Canned goods should undergo an inspection to assure the physical state of the containers. When inspecting canned products, take into consideration the following:
Can labels—the information stamped on the end of each can will be checked to ensure that contents and date of pack are indicated.
Can exterior—general appearance (dents, rust, swelling, leakage).
Contents—odor and taste indicate the condition of the contents. Faded color, loss of flavor, and soft texture are undesirable natural results of aging and chemical action.
Except for coffee and molasses that are discussed below, foods in cans with the following defects are unacceptable and must be surveyed.
Pinholes—cans with tiny holes caused by the action of acid.
Flipper—a can with flat ends, one of which may be forced into a convex position when the other is brought down sharply on a flat surface. It indicates a loss of vacuum due to the formation of gas by bacteria or chemical action on the metal of the can. Regardless of the cause, the contents must not be used.
Springer—a can with one or both ends slightly bulged but yielding to finger pressure. When the pressure is relieved, the ends will again bulge. This condition may be caused by over- filling or by chemical or bacterial action creating gas. Coffee is an exception as the bulging ends are usually an indication of a properly sealed container retaining its natural gases.
Sweller—Both ends of this can bulge out and remain that way. This is indicative of advanced deterioration. Molasses is an exception. Cans of molasses that bulge at the ends are not unusual, particularly in tropical climates. Micro- organisms cannot exist due to high sugar content.
Do not eat, or even taste canned foods that are abnormal in appearance or odor. They must be discarded. If large quantities are involved, submit a representative package for bacteriologi- cal analysis.
Dry food items, other than canned goods, are cereals, sugar, dried fruits, vegetables, flour,