食品专业毕业论文外文翻译3文档格式.docx

1、The freezing process itself does not destroy nutrients. In meat and poultry products, there is little change in nutrient value during freezer storage.PACKAGINGProper packaging helps maintain quality and prevent freezer burn. It is safe to freeze meat or poultry directly in its supermarket wrapping,

2、but this type of wrap is permeable to air. Unless you will be using the food in a month or two, overwrap these packages as you would any food for long-term storage using airtight heavy-duty foil, plastic wrap or freezer paper, or place the package inside a plastic bag. Use these materials or airtigh

3、t freezer containers to repackage family packs into smaller amounts or freeze foods from opened packages. It is not necessary to rinse meat and poultry before freezing. Freeze unopened vacuum packages as is. If you notice that a package has accidentally torn or has opened while food is in the freeze

4、r, it is still safe to use; merely overwrap or rewrap it.FREEZER BURNFreezer burn does not make food unsafe, merely dry in spots. It appears as grayish-brown leathery spots and is caused by air reaching the surface of the food. Cut freezer-burned portions away either before or after cooking the food

5、. Heavily freezer-burned foods may have to be discarded for quality reasons.COLOR CHANGESColor changes can occur in frozen foods. The bright red color of meat as purchased usually turns dark or pale brown depending on its variety. This may be due to lack of oxygen, freezer burn or abnormally long st

6、orage.Freezing doesnt usually cause color changes in poultry. However, the bones and the meat near them can become dark. Bone darkening results when pigment seeps through the porous bones of young poultry into the surrounding tissues when the poultry meat is frozen and thawed.FREEZE RAPIDLYFreeze fo

7、od as quickly as possible to maintain its quality. Slow freezing creates large, disruptive ice crystals. During thawing, they damage the cells and cause meat to drip or lose juiciness. Ideally, food 2 inches thick should freeze completely in about two hours. If your home freezer has a quick-freeze s

8、helf, use it. Never stack packages to be frozen. Instead, spread them out in one layer on the shelves, stacking them only after frozen solid. REFRIGERATOR FREEZERSIf a refrigerator freezing compartment cant maintain 0 , or if the door is opened frequently, use it only for short-term food storage. Ea

9、t those foods as soon as possible for best quality. Use a free-standing freezer set at 0 or below for long-term storage of frozen foods. Keep a thermometer in your freezing compartment or freezer to check the temperature.LENGTH OF TIMEBecause freezing keeps food safe almost indefinitely, recommended

10、 storage times are for quality only. （See freezer storage chart below.） If a food is not listed on the chart, you may determine its quality after defrosting. First check the odor. Some foods will develop a rancid or off odor when frozen too long and should be discarded. Some may not look picture-per

11、fect or be of high enough quality to serve alone, but may be edible; use them to make soups or stews. Cook raw food and if you like the taste and texture, use it.FREEZING GAME MEATSFreshly slaughtered meat carcasses or pieces need to be cooled to below -40 within 24 hours to prevent souring or spoil

12、ing. The meat should be chilled to -32 to -36 . Variety meats （liver, heart or sweetbreads） are ready to be wrapped and frozen after they are cold. For more information, request HGIC 3516, Safe Handling of Wild Game Meats.Quail, dove, duck, pheasant and other game birds should be dressed and gutted

13、as soon as possible after shooting. Cool and clean properly. Remove excess fat on wild ducks and geese since it becomes rancid very quickly. Freeze as directed for poultry. For more information, request HGIC 3515, Safe Handling of Wild Game Birds.Note: Do not stuff poultry or game birds before freez

14、ing them. During freezing or thawing, food poisoning bacteria could easily grow in the stuffing. Commercially-stuffed frozen poultry is prepared under special safety conditions that cannot be duplicated at home.FREEZING FISHFish for freezing should be fresh as possible. Wash fish and remove scales b

15、y scraping fish gently from tail to head with the dull edge of the knife or spoon. Remove entrails after cutting entire length of belly from vent to head. Remove head by cutting above collarbone. Break backbone over edge of cutting board or table. Remove dorsal or large back fin by cutting flesh alo

16、ng each side and pulling fin out. Do not trim fins with shears or a knife because bones will be left at the base of the fin. Wash fish thoroughly in cold running water. Fish is now dressed or pan dressed, depending on size. Large fish should be cut into steaks or fillets for easier cooking. For stea

17、ks, cut fish crosswise into 1 inch thick steaks. For fillets, cut down back of fish from tail to head. Then cut down to backbone just above collarbone. Turn knife flat and cut flesh along backbone to tail allowing knife to run over rib bones. Lift off entire side of fish in one piece, freeing fillet

18、 at tail. Turn fish over and cut fillet from other side. Pretreating: Fish are categorized as either fat or lean fish by the amount of fat in their flesh. Fat fish include varieties such as mullet, mackerel, trout, tuna and salmon. Lean fish include flounder, cod, whiting, redfish, croaker, snapper,

19、 grouper, sheepshead and most freshwater fish. Before freezing, fish can be pretreated to improve the quality of the stored fish. Fatty fish should be dipped for 20 seconds in an ascorbic acid solution made from 2 tablespoons ascorbic acid to 1 quart of cold water to control rancidity and flavor cha

20、nge. Lean fish may be dipped for 20 seconds in a brine of 1cup salt to 1 quart of cold water to firm the fish and decrease drip loss on thawing. （These pretreatments are not needed if a lemon-gelatin glaze is used.） Methods of Freezing: Fish may be frozen using any of the following glazes. If severa

21、l fish are placed in the same package, place freezer paper or wrap between them for easier separation. Lemon-Gelatin Glaze: To prepare glaze, mix 1 cup lemon juice and 1?cups water. Dissolve one packet of unflavored gelatin in ?cup lemon juice-water mixture. Heat the remaining 1 cups of liquid to bo

22、iling. Stir the dissolved gelatin mixture into the boiling liquid. Cool to room temperature. When cool, dip the cold fish into the lemon-gelatin glaze and drain. Wrap the fish in moisture- and vapor-resistant packaging, label and freeze. Ice Glaze: Place unwrapped fish in the freezer to freeze. As s

23、oon as it is frozen, dip fish in near-freezing ice water. Place fish again in the freezer a few minutes to harden the glaze. Take fish out, and repeat the glaze until a uniform cover of ice is formed. Wrap the fish in moisture- and vapor-resistant paper or place in freezer bags. Label and freeze. Wa

24、ter: Place fish in a shallow metal, foil or plastic pan; cover with water and freeze. To prevent evaporation of the ice, wrap the container in freezer paper after it is frozen, label and freeze. Fish Roe: Thoroughly wash and package in freezer containers or bags and boxes, leaving 1 inch head space.

25、 Seal and freeze. FREEZING SHELLFISHClams: Clams can be frozen either in the shell or shucked. To freeze the clams in the shell, simply place the live clams in moisture- and vapor-resistant bags. Press out excess air and freeze. To freeze the clam meat, shuck the clams, then clean and wash the meat

26、thoroughly. Drain and pack in freezer containers, leaving 1 inch head-space. Seal, label and freeze. Crabs: Select only live crabs to prepare for freezing. Crab freezes better if not picked before freezing. Simply remove the back, legs, entrails and gills either before or after boiling the crab for

27、five minutes. （Be sure to cool the crab quickly after it is cooked.） The claws and body or core of the crab that still contains the meat should then be wrapped or ice-glazed and wrapped in freezer wrap or paper. Seal, label and freeze. Lobster: For best quality, lobster should be frozen uncooked. Fr

28、eeze the lobster whole, or clean it and freeze just the shell portions that contain the edible meat. （Some lobsters have large front claws that contain edible meat, while others have edible meat mainly in the tail section.） Freeze lobster in the shell, to help keep the meat from drying out. Simply w

29、rap the whole lobster or lobster portions in moisture- and vapor-resistant wrapping and freeze. Lobster can be cooked and then frozen, but the quality will not be as good.Oysters: Oysters that are still in the shell should only be frozen live. A live oyster will keep its shell tightly closed or will

30、 close when tapped. If you have plenty of freezer space and want to freeze the oysters in the shell, simply wash the shells thoroughly and place in moisture- and vapor-resistant bags. Shuck the oysters to save freezer space. First, wash the oyster shells, discarding any that have died. Shuck oysters into a strainer, savin