More Related Content
What's hot (20)
Similar to Fish canning (20)
More from Al Nahian Avro (20)
Recently uploaded (20)
Fish canning
- 1. Fish Canning
- 2. Fish Canning Canning is relatively modern process, which enable food to be preserved in an edible condition under a wide range of storage condition for long period (from a few months to several years). There are three different stages to the process: • Hermetically sealing the food in a container • Heat ‘sterilizing’ the sealed unit and • Cooling it to ambient temperature for subsequent storage.
- 3. • Although the fish canning industry is more developed in the industrialized countries of the northern hemisphere, a number of tropical countries produce a variety of canned fish product. • Mexico and Brazil, for example, produce large quantities of canned fish, a large proportion of which is sold on the local market. • Morocco is reported as the largest producer of canned sardines in the world and Thailand is now a producer of large quantities of canned tuna. • Tuna is also canned in countries such as the Solomon Island and Fiji.
- 4. Canning industry should be considered only if the following are available- • A regular supply of large quantities of suitable fish (and other materials e.g. salt, oil, etc. ) at a reasonable price. • An adequate supply of cans at an economic price. • Adequate manpower. • Suitable infrastructure (energy, water, transport etc.) • A market for the finished product.
- 5. Definition of Canning • Canning may be defined as packaging of food in a hermetically sealed container and obtaining commercial sterility through the use of heat processing. • Commercial sterility may be defined as the degree of sterility necessary to destroy all harmful bacteria without changes in food quality. • Canning is long-term preservation method storage range from 2-10 years with maintaining more or less same quality
- 6. Principles of canning: • To obtain commercial sterility • To preserve the fish in a hermetically sealed container by subjecting to require heat processing. • Maintenance of bacteriological principles. • Maintenance of anaerobic condition within the can.
- 7. Steps of fish canning: 1. Selection of raw materials 2. Treatment before canning. 1. Nobbing 2. Washing and de-scaling 3. Brining 3. Packing/ filling the can 4. Exhausting. 5. Closing the can 6. Washing. 7. Heat processing/ retorting. 8. Cooling. 9. Labeling and boxing.
- 8. 1. Selection of raw materials: • Mature, pre-spawning fish and medium fatty fish are better for canning. Eventually fish with the following characteristics are used for canning- – Excess bone – Taste less – High fishy odour – Fish with hard and farm muscle. – Available Eg: Sardine, Hilsa, Salmon, Herring etc
- 10. 2. Treatment before canning: • Nobbing: In the case of larger fish, such as herring and pilchard, the head and gut are removed, but not the roe or milt. This process of removing head and gut in one operation is called nobbing. • Washing and de-scaling: The next operation is de- scaling; remove fins, viscera from the raw materials and washing. Nobbing releases blood that must be removed because it causes brown staining in the processed fish. Washing also removes surface slime and dirty materials from fish. • Brining: The fish are immersed in a concentrated solution of common salt for a predetermined length of time. Salt is absorbed by the flesh and imparts a desired flavour to the finished products in which a salt content of about 2 % is acceptable.
- 11. Nobbing process Washing machine Washing
- 12. 3. Packing/ filling the can • The above treated fishes are filled in the can either by manually or mechanically usually a small top space is left which is also called head space and generally filled with inert gas. • The fishes are arranged inside the can as compact as possible. • Necessary additives (Salt, Tomato sauce, Starch, Sugar etc) may be used to develop characteristics flavour and improve keeping quality.
- 14. 4. Exhausting Exhausting is done by the application of heat. By this the gas inside the headspace and between two fish pieces will be removed and a partial vacuum will be formed. Exhausting is done to prevent- • Bulging of can • Oxidation of the food • Inside erosion of the tin plate.
- 16. 5. Closing the can: All fish cans prepared in this country are closed by the double-seaming method and the operation is usually called seaming. A seal must be achieved that will prevent passage of contaminating material, carried either in air or water, into the can after it has been sterilized. Proper care and maintenance of seaming is vital and its performance should be checked at frequent intervals throughout the working day.
- 18. 6. Washing: • Washing of can is done by the hot water spray to remove adhering materials.
- 19. 7. Heat processing: • It is the most important step during the whole canning procedure. • It is done for predetermined time at the respective temperature. • To fulfill the canning objectives 32 minutes are required at 1100 C or 2.5 min is required at 1210 C. • The temperature of the can is determined a recorder which is called thermo couple. • Heat processing is done in a special instrument called retort and so the process is called retorting.
- 20. 8. Cooling: • Cooling is done as quickly as possible after retorting. Otherwise off flavour may produce because considerable changes may take place during heat processing
- 21. 9. Labeling and boxing: • After cooling, cans of large fish such as herring and pilchards are stored for a period of weeks before labeling. • Cans of small fish are usually labeled directly, since thest are not so susceptible to damage. • Ingenious machines are available for labeling dingley cans, and are capable of fixing the lid label, placing a key on this, and wrapping the whole in a greaseproof wrapper. • Larger cans may have the top label pasted on by hand, and the side label by machine. • Many canners label by hand, making use of female labour during off-season period. • In recent years, the introduction of decorated lids has cut down the use of paper labels.