FIELD OF INVENTION
The present invention refers to a continuous blanching system for processing of vegetables. The continuous blanching system of the present invention eaves time and thereby more economical. The system is suitable for leafy, root, tubers and other vegetables.
PRIOR ART
Blanching is a pre-process for vegetable dehydration or juicing in order to inactivate the enzymes and to expel tissue gases. Generally, boiling water blanching or steam blanching is adopted as a batch process. Steam blanching is more efficient because of the lower loss of nutrients and shorter period of exposure to heat. Blancher for commercial processing of vegetables is generally designed to suit the utility of the company. Parkes (USP 452537 0, 1985) patented water type blancher where a food system was adopted to water blanch the vegetables. The loss of water soluble nutrients is the great

limitation of this process. Anderson and Niels (USP 4702161, 1987) patented a spray type integrated vegetable blancher and cooler, where the blanching liquid was sprayed through the nozzle on to the vegetables travelling through a tunnel on a conveyor belt and subsequently cooling liquid was sprayed. The spraying of blanching and cooling liquid in a sequence may not give the adequate treatment to the vegetables. Yet another disadvantage is that in the normal blanching, liquor, salts also help to take care of the quality c f vegetables during storage and in this system it is not possible since the cooling is carried out with the help of a washing liquid.
Zittel (USP 5146841, 1992) patented a open throat blancher of cylindrical type which rotated he food product in the drum. However, the control of temperature and heat transfer to the food material was not uniform. Yet another limitation was that the greater mechanical damage to the product because of rotating of the drum, rendering it unsuitable for soft vegetables.

Zittel (USP 5329842, 1994) patented a combination of blancher and cooler where the earlier blancher was attached with a cooling compartment. Again, the limitation has been the mechanical damage to the product because of cylindrical shape.
Zittel (USP 5429041, 1995) upgraded the above with multiple heating zones for better control of product heating. However, the blanching of the food product through a range of temperature regions cause heavy thermal abuse and reduced the quality. Yet another limitation was that the blancher tank was separately connected through a frame to the main portion of the blancher and this involved separate frame work welding making it less economical and labour intensive.
Zittel (USP 5752431, 1998) further patented a blancher with multiple cooling zones. The limitation of this system was that blanching and cooling had to be followed alternatively. Yet another limitation was being a batch process.

Zittel (USP 5105485, 2000) patented a pressurized rotary blancher for quick heating to a desired temperature. But, the limitation was the lack of loading and unloading of the products prior to and after blanching. Yet another limitation of the design was that the rotary blancher required more metal reinforcement, making it uneconomical. The ro ;ary blancher was similar to an agitating retort used for thermal processing of ready-to-eat products, limitation being the destructuring of the products.
Zittel etal (USP 6234066 2001) patented a rotary blancher for processing food products and its method of operation (USP 6263785 2001). Such a blanomer could use discharge of liquid and gas for heavy food products and gas for low density products, limitation being a batch process. Zittel etal (US 6615707, 2003) has patented frameless blancher for food with complicated design.

Thus the existing blanchers are suited for batch process or semi-continuous process and are not economical. The provided information does not clearly indicate which type of vegetables can be blanched. In the present invention, a continuous blanching system suitable for various vegetables, such as carrot, potato, curry leaves, beans etc. based on a controlled feeder, conveyor and steam injection has been developed.
OBJECTS OF THE INVENTION
An object of the invention is to propose a continuous blanching system for processing of vegetables.
Another object of this invention is to propose a continuous blanching system for processing of vegetables and allows an automatic dispensing of vegetables.

Yet another object of this invention is to propose a continuous blanching system for processing of vegetables which provides a uniform heat transfer to achieve adequate blanching.
Still another object of this invention is to propose a continuous blanching system for processing of vegetables, which is suitable for all vegetables.
STATEMENT OF INVENTION
According to this invention there is provided a continuous blanching system for processing of vegetables comprising of a tray (1) conveyor having a chain (2) running through a blanching tunnel (3) wherein an upper tray conveyor (4) is provided for transportation of vegetable products, characterized by a steam spraying system positioned over the upper tray conveyor (4) to spray steam thereon and a hopper feeding unit (6) for continuous introduction of vegetables into the blanching zone.

BRIEF DESCRITPION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawing and wherein:
Fig 1. shows :- Isometric view of continuous blanching system;
Fig. 2. shows:- Isometric view of Stainless Steel Tray;
Fig. 3 shows:- Isometric view of steam spraying assembly;
Fig. 4 shows :- Side view of steam spraying assembly;
Fig. 5 shows :- Top view of continuous blanching system;
Fig. 6 shows :- Side view of continuous blanching system.
DETAIL DESCRIPTION OF INVENTION WITH REFERENCE TO ACCOMPANYING DRAWINGS
Reference may be made to the accompanying drawings.
The continuous system for blanching of root and leafy vegetables comprising of a tray (1) conveyor having a chain (2) running through the adjustable blanching tunnel (3). The vegetable products are transported continuously in a controlled

movement by upper tray conveyor (4) through the treatment zones defined in the adjustable blanching tunnel. The blanching zones are provided with an arrangement of spray nozzles (5), located to spray steam on to the upper tray conveyor (4) containing vegetables. The steam is discharged at a controlled rate. Such a blancher can be used to process a wide range of vegetables using steam as the heating medium. During operation, the vegetables are continuously introduced into the adjustable blanching zone through the hopper feed mechanism (6). As a result, a large quantity of vegetables can be quickly blanched.
Further, the continuous blanching system for vegetables as well as leafy materials comprising of a longitudinal casing (7) having a product inlet (8) and end product outlet (9), oppositely located and spaced apart side walls and a 'L' angle frame (10) which extends between the said inlet and outlet ends and closes the spacing between side walls to define a product adjustable blanching tunnel (3).

A tray conveyor (4) is provided with the system for receiving and supporting the vegetable and leafy product thereon as well as for moving said product from inlet end (8), through said product adjustable blanching zones to the outlet end (9).
A product hopper (6) feeding mechanism unit is arranged at product inlet end for receiving said vegetable and leafy product, supplying and distributing the product to the said tray conveyor (4) in controlled quantities.
A product adjustable blancning zone is arranged in the treatment tunnel comprising of steam spraying nozzle (5) arrangement over the said tray conveyors (4) moving at a controlled speed and sprayed with steam.
The hopper (6) provides the feed mechanism to deliver required quantity of raw materials to the tray conveyors (4). This fully enclosed system allows products not only to be dispensed

accurately but also with minimal damage and induction of products at adjustable feed rate through a stepper motor. The tray conveyor (4) assures longitudinal movement of the specified quantity of the product along a specified path using sprockets (11), chain (2) and varied movement with the help of a variable speed DC motor, three phase input (440 V, 50 Hz), reduction gear box 5 to 50 RPM, interconnected and enclosed. This system is compact with adjustable RPM and residence time for controlled movement of the products.
The steam spraying system (15) placed above the conveyor (4) for controlled, uniform, effective distribution and transfer of heat to the individual units of the product without altering the structure, during the entire movement from feed to the delivery zone. The steam pressure can be adjusted depending on the type of the product.

The entire blanching operation involving product feed rate, residence time (movement of the tray conveyor) can be controlled and optimized with the help of a control panel which houses complete electrical/electronic gadgets. The stainless steel pipes and spraying nozzles are connected to the main steam supply.
The entire conveying and steam spraying system is enclosed in a cover for thermal stability as well as to avoid steam leakage to the surroundings.
The vegetables are presoaked in the requisite salt solutions before blanching for a period of about 30-60 minutes. The vegetables are drained to remove the excess soaked solution and fed to the hopper. The hopper feed mechanism controls and allows known quality of the product on to the tray conveyor. The product passes the blanching zone in a controlled residence time. The various vegetables sue a as carrot, potato, curry leaves

were blanched with residence time of for example 3, 5 and 6 minutes, and steam pressure of for example 4, 6 and 8 lbs/sq inch.
ADVANTAGES OF THE INVENTION
1. Reduction in the loss of water soluble nutrients.
2. Adequate treatment to the vegetables without the requirement for separate washing liquid with the spraying of steam under controlled temperature and pressure during blanching.
3. Uniform and effective distribution as well as transfer of heat to the individual units of the material.
4. Minimal damage to the product during the entire blanching operation even for the soft vegetables.
5. No requirement of separate blancher tank as the blanching media (steam) comes from the boiler which is one of the essential equipments for food processing unit.

6. A continuous processing system, suitable for a wider range of vegetables.
7. Easy loading and unloading of the products prior to and after blanching.
8. It is economical requiring minimum metal reinforcement.
9. No destructuring of the products during entire blanching operation.
10. No discharge of liquid and gas for heavy food products and gas for low density products being a continuous process and simple in design.

11. Counter current flow of the material for better heat transfer.
12. Regulated and controlled blanching time for all types of vegetables.
13. Minimum leaching of soluble solids.
14. Low consumption of energy and water.
15. Provision of a control panel for coordinating and controlling the operations.
16. Continuous introduction of the vegetables into the adjustable blanching zor e through the hopper feed

mechanism which causes quick blanching of a large quantity of vegetables.
It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims: -

WE CLAIM
1. A continuous blanching system for processing of vegetables comprising of a tray (1) conveyor having a chain (2) running through a blanching tunnel (3) wherein an upper tray conveyor (4) is provided for transportation of vegetable products, characterized by a steam spraying system positioned over the upper tray conveyor (4) to spray steam thereon and a hopper feeding unit (6) for continuous introduction of vegetables into the blanching zone.
2. A continuous blanching system as claimed in claim 1, wherein a longitudinal casing (7) having a product inlet (8) and end product outlet (9), oppositely located and spaced apart side walls and 'L' angle frame (10).
3. A continuous blanching system as claimed in claim 1 or 2, wherein the system has a control panel for controlling and optimizing the blanching operation.