Presentation on theme: "Canning of Whole Tomato Next. Tomatoes may be preserved for long time by processing them in cans. The cans are made of tin plate with special lacquer."— Presentation transcript:
Canning of Whole Tomato Next
Tomatoes may be preserved for long time by processing them in cans. The cans are made of tin plate with special lacquer coating to avoid chemical contact between container surface with contents. The lacquers are of different type plain, AR (acid resistant), R (Sulphur Resistant), MFR (Meat Fat Lacquer) etc. For tomato canning AR cans are used. Introduction Next End Cans are normally procured in flat form. This saves on transport cost and storage convenience Canning of Whole Tomato
The processing of sealing tomatoes hermetically in containers and sterilizing them by heat for long storage is known as canning. The principle of canning is the destruction of spoilage microbes within the sealed container by heat application Definition of Canning Next End Previous Canning of Whole Tomato
Preparation of Tomatoes for Canning Next End Previous Peeled tomatoes are canned and even size whole tomatoes are preferred. But economy pack may contain cut and small size fruits. The tomatoes may be canned either in brine or tomato juice. It is difficult to peel the thin skin of tomatoes. The process to remove peel from tomatoes is called scalding. Canning of Whole Tomato
Preparation of Tomatoes for Canning Next End Previous In this process the washed whole tomatoes are dipped in boiling water for 3-4 minutes followed by dipping in plain water. This sudden change of temperature raptures / loosens the tomato peel. The peel can be removed manually or mechanically with spray jets. Canning of Whole Tomato
Sterilization of Cans Next End Previous Flat cans are reformed in round shape with the equipment called reformer. Reformed (rounded) cans are passed through next equipment called flanger both the sides are bent to fit lids. Canning of Whole Tomato The flanged cans are ready to fix lid on one side with the help of can seamer.
Sterilization of Cans Next End Previous Cans with one fixed lid are sterilized by boiling in big pan. (Boil cans in water for 3- 5 minutes) or Can Sterilizer Is used for large scale production units. Canning of Whole Tomato Hand operated Can Seamer is used in home scale preservation and automatic seamer is used in commercial processing units.
Canning of tomato Next End Previous The trimmed tomatoes are dipped in boiling water (3-4 minutes) followed by dipping in plain water to burst / crack (loosen the tomato peel). Canning of Whole Tomato Deep red coloured sound tomatoes are selected and washed, trimmed for removal of tops. The skin is peeled manually for small size production or with mechanical water spray jets in commercial production units.
Canning of tomato Next End Canning of Whole Tomato Previous Peeled tomatoes either whole or cut are filled in the sterilized cans. The proportion of tomatoes and covering liquid (brine or tomato juice) in the can are 45% and 55% respectively. Filled cans are exhausted to remove the entrapped air (the main cause of spoilage). Exhausting is done in boiling water in the pan or exhaust box for minutes. The other lid is placed on the can while exhausting. Canned Tomato
Sealing of Canned tomato Next End Canning of Whole Tomato Previous The exhausted cans are sealed. The sealed cans are sterilized in boiling water for 20 minutes or with steam in retort. The sterilized can are cooled to room temperature and finally labeled. Packing into tin container
Let us sum up Next End Canning of Whole Tomato Previous Fully ripe, firm and round tomatoes of uniform size are selected. Fruits are washed thoroughly with water to remove dirt, dust etc. Peeled tomatoes are filled into clean cans and covered with tomato juice or brine. Fruits are blanched to soften the peel and then peel is removed by hand. After exhausting (in steam bath) cans are sealed immediately by double seamer
End Canning of Whole Tomato Previous Sealed cans are then thermally processed at high temperature (100 O C) for about 20 minutes After thermal processing, the cans are cooled rapidly to about 35 O C in cold water and then stored after labeling Let us sum up