Exercise
|
Practical 1 - Equipment & machinery used in food processing units |
|
Aim: To familiarize the students with the machineries and equipments used in fruit and vegetable processing. Theory: The students will visit the processing unit/pilot plant and familiarize with different machineries and equipment used in fruit processing units. The students will observe the layout and the details of the machinery for different unit operations viz; raw material receiving, washing, sorting/grading, peeling, slicing, pulping, heating, filling, exhausting, sealing, sterilization/processing, labelling and storage for different products. The list of the machineries and equipments and important chemicals used in fruit preservation is as under: Apparatus/machineries/equipments used in food industries A.. Basic equipment/ accessories 1. Weighing balance (1-10kg)and electronic balance (for chemical weighing) 2. Cutting Knife (SS), coring knife, pitting knife, peeling knife 3. Abrassive peeler 4. Working table 5. Buckets, Tubs, Jugs 6. Belt conveyors 7. Fruit /vegetable washer 8. Fruit /vegetable blancher 9. Bottle washer B. Heating equipment 1. Hot plate 2. Diesel bhatti 3. LPG bhatti/gas stove 4. Boiler C. Juice extraction/pulping Hand operated /motor driven 1. Fruit grater/ Fruit mill 2. Basket press 3. Hydraulic press 4. Rosing machine/burring machine 5. Screw type juice extractor 6. Pulper D. Machineries for canning unit
F. Sealing/closing
G. Drying/Dehydration:
H. Oil extraction
I. Instruments for analytical purposes
1. Belt Conveyor: The conveyers are suitable for feeding, inspection and initial preparation of fresh fruits and vegetables. It can handle 1-10 tonnes of material per hour. 2. Fruit and vegetable washers: This machine is useful for washing the fruits and vegetables. The capacity varies between 15 to 20 kg per batch with a cycle time of 5 to 10 minutes depending on condition of fruit or vegetable. It is made of stainless steel tank with wire mesh basket, water circulation pump and agitation equipment and works with 3 HP motor. For washing, the commodities are subjected to strong water agitation for removing the dirt and dust. Roller brushers are used for proper washing. Fresh water is also sprayed in the second stage washers. 3. Halving and burring Machine: The halving and burring machine is used to extract juice from citrus fruits like orange, mosambi, grapefruit, lemon (Hill lemon), lime etc. The fruit in a cup of machine is cut into two halves by a stationary or revolving knife. The burrs (roses) are made of stainless steel, aluminium or non-odorous wood. They are conical shape and are ribbed. The fruit half is held against the revolving burr and the reamed juice is collected in a vessel. By regulating the speed of burr and the pressure on the fruit held against it, optimum juice recovery can be obtained besides avoiding extraction of oil, which may otherwise cause bitterness in the juice. 4. Fruit grater: The fruit grater is used for grating/crushing of fruits for its further use in extraction of juice by passing through a basket or hydraulic press. The grater consists of a heavy steel cylinder fitted with cirrated knives with moving hammer. Apples are fed whole or halves into the hopper and are crushed between cylinder and knives and crushed material fall into a receptacle below. Other fruits like pear, carrots, aonla after removal of seeds etc can also be crushed in the grater. 5. Fruit crusher: The crusher consists of two fluted or grooved roller made of wood, and revolves towards each other arranged horizontally. The fruit fed through the hopper, falls between the rollers and get crushed. The grapes are crushed by using grape crusher. 6. Juice extractor (Hand operated): The machine is used to extract the juices from soft fruits like orange, grapes etc. The machine is conical screw feeder type with top feeding arrangement and bottom discharge separately for juice & pulp. All the contact parts are made up of stainless steel. The capacity of the machine is 30 -50 Kg/h. 7. Basket/hydraulic press: The basket press (Fig. 1.1) consists of a strong cylindrical basket made of wood and rests on a wooden or metal base on a frame. There is a strong screw at the top of the frame. The sliced fruits are folded in a nylon cloth and placed inside the basket alongwith wooden frame. The screw is turned either by hand or fruit pieces are pressed by using a hydraulic pressure exerted by the hydraulic press which cause the juice to ooze out with a hydraulic pump. The basket/hydraulic press is useful in extracting juice from the apple, pear, grape, jamun, pomegranates, phalsa etc. 8. Fruit and vegetable pulper: It is useful for extracting pulp of most fruits & vegetables like mango, apple, tamarind, custard apple, plum, apricot, peach, kiwi, tomato etc. They are available as coarse pulper, fine pulper, pulper cum finisher and baby pulper. The capacity varies from 50-100 kg/ h or even 500kg/h or larger depending upon type, size and quality of product. The main body (available in brush type or canvas screw type model) is stainless steel and stand is of milled steel (MS) with motor. The pulper (Fig. 1.2) consists of two brushes & two beaters which give a combined beating and brushing action. They are also available with four beaters or four brushes depending upon the fruits to be handled. The gap/clearance between the sieve and beaters/brushes can be adjusted to suit different sizes and qualities of products to be pulped. The sieve is provided with perforations of different sizes and is easily removable for cleaning. All contact parts are of stainless steel. All parts can be easily dismantled and reassembled to facilitate easy inspection, proper washing, cleaning and periodic maintenance. Fruit/vegetables with or without heating are fed from the hopper and after pulping action, the extracted pulp and separated seeds/peel are collected from different ends. 9. Steam jacketed kettle: It is mainly used for heating of pulp/juice, syrup, brine etc. Generally double jacketed stainless steel boiling pan is used. Steam from boiler is supplied in the space between the outer jacket to heat the inner pan in which product is placed for heating. Steam-jacketed kettles are used to prepare a variety of food products like jams, jelly, fruit drinks, sauces, ketchup etc. Different types of kettles are: steam jacketed kettle (tilting type) (Fig 1.3), Steam jacketed kettle (fixed type) and fixed type kettle with stirrers. 10. Fruit and vegetable blancher/Hot water blancher: Hot water blanchers (Fig 1.4) are boiling pans/tank that is used for blanching of fruit and vegetables. They are made up of stainless steel or aluminum. The steam from the boiler is connected to the blanching tank to heat the water. A perforated basket is used to place the fruit/vegetables in the blancher for predetermined period and removing the same after the process. In steam blanchers, the conveyor belt is used which is covered with steam chamber. The product is carried by a belt conveyor whose speed is adjustable by manual speed reducer to optimize the processing times according to the production rates. The blancher creates a heating-process, in which the products are exposed to hot steam, with an estimated temperature of 90 to 1000C. The products are moved by a belt and proceed through the steaming process for an estimated 6-10 minutes. Belt speed and amount of steam is adjustable, enabling to customize the blanching process depending upon the commodity. The main components of the blancher are: Belt for supporting/holding the product; Electrical gear motor with variable speed; Provision for hot water/steam and its recirculation in the heat exchanger and Control panel. 11. Crown corking machine: The crown corking machine (Fig 1.5) is hand operated and can cork 20-25 bottles per minute. It is suitable for sealing the juice bottles with crown corks. 12. Pilfer proof (PP) cap sealing machine: It is used for sealing of bottles in which screw type caps are used squash bottles are sealed by using PP caps. 13. Bottle washers: Bottle washers are provided with revolving brushes to which bottle/jar is placed for automatic washing action. The time consuming part of bottle washing is rinsing out the detergent and bottle washers are used to reduce this time. They are made by soldering vertical pipes onto a larger base pipe and connecting the base pipe to a water supply. For rinsing, the bottles or jars are inverted over the vertical pipes and rinsed until free of detergent. 14. Laboratory glassware/equipment: The laboratory equipment used for testing fruit and vegetable products includes glass beakers, pipettes, flasks and a burette (Fig 1.6). Pipettes are used to suck a known volume of a chemical and drop it into a sample of juice. Care is needed not to suck chemicals into the mouth. The burette is used to accurately measure the amount of a chemical that is added to a sample of juice when testing the amount of acid in the juice. Glassware should be cleaned with detergent and bottle brushes, rinsed with clean water and then rinsed again with distilled water. 15. Refractometer: Hand refractometer (Fig 1.7) measures total soluble solids (TSS) as 0Brix, which corresponds to % sugar. These are available in three ranges 0-320Brix, 28-620Brix and 58-920Brix and used for measuring total soluble solids in fruit juices, sauces, syrups, jams, jellies, squashes, preserves etc. Abbe refractometer measures TSS in the range of 0-100oB. Abbe refractometer is expensive instrument but it gives an accurate measurement of TSS and can also be used for standardization of hand refractometer. 16. Weighing balance/scales: Small scales (0-2kg), medium portable scales (up to 10kg) and large scales (upto 100kg) are used to weigh small amounts of ingredients or laboratory chemicals, weighing of ingredients and products and weighing of fruit and vegetables respectively. Care is needed to properly clean scales if they have been used to weigh chemicals. The small scales can be operated using batteries or mains power supply.  Machineries and equipments for canning industries    1. Can body reformer: The cans are available in the market as in flattened form and therefore the reforming of these cans is needed. The can body reformer (Fig. 1.8) can reform 10-15 cans/minute. Large capacity reformers are also available. 2. Flanger: After reforming of cans, the flanging of can ends is done by using flanger machine (Fig. 1.9). The ridges/ body hooks are formed on the both ends of the cans for proper sealing of cans. 3. Lid embossing/Coding machine (Fig 1.10): The embossing is done before seaming and it provides a code with the necessary information about the product like name of canning unit, product packed in the can, date of packing, lot number etc. 4. Double seamer: It is suitable for high speed air tight seaming of the open top sanitary (OTS) cans (Fig 1.11). The seaming of the cans is done for getting hermitic seal of cans. Double seaming is a two step operation. In the first operation, the can lid is inserted on to the can body hook by holding and rotating the lid-in-position can between two rollers. This operation is called as clinching; during which first operation roller gently guides the lid in the body hook. The next step is to press the seam using the second operation roller, which results in an appropriate overlap of the body hook and cover hook to provide appropriate countersink. Between the cover hook and body hook lies a layer of sealing compound which ensures the sealing process. 5. Exhaust box: The exhaust box (Fig. 1.12) is suitable for exhausting the air from filled cans before seaming. The purpose of exhausting and creation of vacuum is to create an anaerobic environment inside the can that would inhibit microbial spoilage. The can covered with the lid or loosely sealed are exhausted at about 82-87oC or on a moving belt through a covered steam box. The time of exhaust varies from 5 to 25 min depending upon the nature of the product. At the end of the exhausting, the temperature at the centre of the can should be about 79oC. 6. Can sterilizer/Autoclave: After sealing, the cans are placed in sterilization tank for sterilization/processing of cans. Sterilization tank is made up of milled steel or stainless steel which is connected with steam pipe to supply steam from the boiler. Similarly, retort/autoclave (Fig. 1.13) can also be used for sterilization of sealed cans of vegetables and mushroom which are processed under steam pressure. Machineries required for Canning of fruits and vegetables   |
Last modified: Wednesday, 7 March 2012, 8:47 AM