Canning of fish

Canning is the comparatively modern method of preserving food, its origin dating form the discoveries of the French inventor, Nickolas Appert, in 1795. He invented a process of heating foods sealed in glass cans, which caused them to keep in definitely. Canning has advantages over some of the more ancient method of food preservation such as drying, salting, freezing, and cold storage.

Fish canning comprises the following steps: cleaning and trimming, salting, cooking or drying, packing into cans, exhausting, sterilizing, or processing by heat and then sealing.

Cleaning and trimming. In the canning of fish products, cleaning and trimming generally consist in the removal of the head, viscera and tail fin, the washing of the eviscerated fish to remove blood, and the trimming of the fish into pieces of proper size to pack into cans.

Brining and pickling. In order to draw out the blood from the tissues, to give the flesh a proper degree of firmness and the desired flavour, it is practice to hold many kinds of fish before or after trimming in brine for a varied length of time. The time of holding and the strength of the brine depend largely upon the size and fatness of the fish, the nature of subsequent operation.

Cooking. Many fish are subjected to some cooking or drying process before being packed is cans. This removes excess moisture and supplements the cooking of the fish in the can during the subsequent sterilizing process. Fish may be steamed and dried before packing or they are dried first and then cooked by a frying process.

Filling. Filling may be accomplished mechanically or by hand. Mechanical filling is faster and gives a more accurate control of the net weight or volume of liquid.

Exhausting. The objective of the exhaust is to remove air and gas from the can that the contents will be in a vacuum after processing and cooling.

But the disadvantage of heat exhausting are as follows: nonuniformity and insufficiency of vacuum, protein denaturation, and detarioration of flavour. That's why exhausting is widely replaced by vacuum-sealing devices. These devices ensure more uniform vacuum, lessen the development of oxidized flavours and lessen destruction of vitamins.

Seaming (Sealing). Seaming is the step in which the cans are passed through a sealing machine that rolls the curl of the cover and the flange of the can with the gasket or sealing compound into air-tight double seam.

Sterilization. The canning of food products being based on the principle of sterilizing by heat, the final cooking or "process" is the most vital process and important step in the canning procedure.

The term process as used in the canning industry, is synonymous with cook, and designates, in terms of temperature and time, the heat treatment given to the preliminary sealed container. The minimum requirement for the process of any product is that it be adequate to destroy the most heat-resistant organisms.

In order to secure adequate sterilization within a reasonable time it is customary to sterilize cans in continuous rotary sterilizers where the cans are processed by steam under pressure.

Testing. After the cans have been cooled, it is customary to test them for leaks or defective seams before they are lacquered in an automatic machine.

Exercise 4. Find the Russian equivalents for the following:

modern method of preserving food, the canning of fish products, a sealing machine, heat exhausting, the curl of the cover, protein denaturation, double seam, the flange of the can, nonuniformity and insufficiency of vacuum, by hand, steamed and dried before packing, replaced by vacuum-sealing devices, being based on the principle, before or after trimming, the minimum requirement, the objective of the exhaust, continuous rotary sterilizers.

Exercise 5. Find the English equivalents for the following:

предварительно закатанный, проверять на утечку, герметичный, двойная закатка, неоднородный, процедура консервирования, эксгаустирование, кромка крышки, уплотнитель, обрабатывать паром, лакировать, подвергаться, выпотрошенная рыба, в тузлуке, до или после разделки, удалить воздух, стерилизовать банки, желаемый вкус, обеспечить соответствующую стерилизацию.

Exercise 6. Complete the sentences using information from the text:

1. The objective of the exhaust is to…

2. The canning of food products being based on the principle of sterilizing by heat,…

3. Many fish are subjected to…

4. In order to secure adequate sterilization…

5. Fish canning comprises the following steps…

6. The minimum requirement for the process of any product is…

7. Mechanical filling is faster and gives…

Exercise 7. Fill in the blanks with prepositions over, of, for, in, upon, by:

1. Exhausting is widely replaced … vacuum-sealing devices.

2. The time … holding and the strength … the brine depend largely … the size and fatness … the fish.

3. It is practice to hold many kinds … fish before or after trimming … brine … a varied length of time.

4. Trimming generally consists … the removal … the head, viscera and tail fin.

5. Canning has advantages … some of the more ancient methods.

Exercise 8. Say if the sentences are true or false using the information from the text:

1. Filling may be accomplished only by hand.

2. It is customary to sterilize cans in batch rotary sterilizers.

3. Canning is the very ancient method of preserving food.

4. Exhausting ensures more uniform vacuum and lessen destruction of vitamins.

5. The final cooking or "process" is the most vital process and important step in the canning procedure.

6. It is vital to test cans for leaks or defective seams.

7. Nickolas Appert invented this method in 1795.

Exercise 9. Change the following sentences into the Passive Voice:

1. The workers have cooled the cans after sterilization.

2. These devices ensure more uniform vacuum.

3. Sealing machine rolls the curl of the cover.

4. The exhaust removes air and gas from the can.

5. Vacuum-sealing devices replace exhausting.