Page 1

2002

Packaging soft drinks and reconstituted juices in beverage cans

In recent years we have witnessed growing consumption of beer and soft drink, both carbonated and noncarbonated, marketed in cans.

This brochure introduces basic concepts and general information on the manufacture of cans, raw materials, the production of beverages, and quality control of these systems.

Caniel laboratory will be pleased to serve its customers and provide them with information on any matter associated with the issues covered in this bulletin.

The attached recommendations are up-to-date and replace any previous recommendations on the subject These recommendations should be seen as informative only Caniel is not responsible for the results of following the guidelines and information contained in this brochure

Page 2

1. The Can Manufacturing Process Two-piece cans (drawn cans) are produced using a special technology that includes pressing the medal into cups using a dies and then forming the cup into a can using a process known as drawing and wall ironing.

The can is printed on the outside and coated on the inside. This method guarantees that the can will be impermeable and able to withstand standard manufacturing processes and corrosion.

basecoat: The basecoat protects the outside of the can and provides background color for the printing system.

Inside coating (first coat): First coat is sprayed on the can in order to create a protective layer between the metal and the product during storage. The concave part of the bottom of the can (on the outside) is coated, too, in order to prevent external corrosion.

Inside coating (second coat): Second coat covers exposed spots that were not covered by the first coat, so as to guarantee that cans have a minimum of exposed metal.

Automatic equipment is installed on the production line to inspect all the cans using a light tester that is extremely sensitive to holes and leaks. Damaged cans are rejected too.

2. Packing

The cans are placed on pallets. Currently the pallets are 21 rows high. Each row contains 361 cans, for a total of 7,581 cans on a pallet.

Because of the height of the pallet and the need to stabilize it, it is held by a rigid metal frame, enclosed by four loops of packing tape.

Stretch-wrap plastic isolates the cans and protects them from the ambient environment.

Each pallet has a paper label that indicates the product name, production code, and serial number. Reference should be made to this label if there are any problems or failures.

Production date is printed on each can in a hidden form.

After unloading the cans, customers are requested to place the frame back on the wooden pallet and to return them to Caniel.

Page 3

3. Productions and Filling with Carbonated Beverages

3.1 Empty-Can Conveyor

Because cans are delicate and lightweight, care must be taken in every aspect of moving empty cans. Make sure that all passages are very smooth to permit the ready flow of empty cans. The slops of the filling lines should be moderate. Make sure that the conveyor is always full of cans.

This will prevent unnecessary damage to cans.

The can-send system at the entrance to the filling machine must grip the can. This method keeps cans from collapsing when they come into contact with the can send.

3.2 Filling Machine (Filling Process)

Phase 1 Moderate pressure locks the can onto the fill head. Phase 2 The actual filling stage, during which the can is locked with a working

pressure that permits good filling

Balance the pressures in the filling system so as to avoid exerting a force of more than 100 kg on a can.

The filling-base pressure should correspond to the equipment manufacturers instructions and take account of the maximum permissible load on a can.

To guarantee normal flow of cans at the entrance to the filling machine and its exit make sure that:

3.2.1 The empty-can feed conveyor is 0.0250.050 mm above the filling bases.

3.2.2 When the full cans are removed from the filling bases they are about 0.0250.050 mm above the conveyor leading to the seaming machine.

4. Seaming Machine

To ensure a proper seam make sure of the following:

4.1 Recommended system of rollers and seaming heads

4.2 Preventive adjustment should be carried out at least four times a year and after every modification or refurbishing, in order to guarantee proper seaming and keep cans from collapsing. During the adjustment, check pin height (the weighted height between the base plate at the end of the first action and the seaming head),

Page 4

the base force exerted, and the gap between the first-operation and second-operation rollers.

4.3 Strict adherence to recommended double seam dimensions as stated in the information brochure, Recommended Seam Dimensions for Aluminum End B64 206 on Caniel Steel Cans (see 21 below).

5. Full-Can Conveyor

After cans have been filled and seamed they should be flipped over, so that the cover is on the bottom, and placed in the heater in this orientation. Turning them upside down is very important for detecting leaks. Most flaws in two-piece cans will be around the easy-open end and seam.

Moving cans this 3 way ensures that leaks are detected during heating process, with can rejected immediately by the fill-height meter located right after it. To prevent unnecessary damage to the seam, the cans should be turned right side up again immediately after heating, so that the easy-open end faces up.

6. Storage (empty and filled cans)

The Cans must be stored in proper conditions and under cover.

Make sure that cans are not exposed to direct sun (printed colors fade in the sun), rain, high humidity, mechanical injuries and blows, and inappropriate storage temperatures.

7. Storing filled Cans on Pallets

7.1 Make sure filled cans are packaged completely dried, especially around the seam.

For shrink-wrapped packages, take special care that the cans are completely dry before wrapping. Plastic shrink-wrap does not breathe, so any water left on the cans cannot evaporate during storage and will cause extremely rapid corrosion.

The use of perforated shrink-wrap is recommended, along with high-pressure air nuzzles to remove any remaining water after the cans have been cooled, or a final rinse with both de-ionized water and air nuzzles.

Dents or scratches during storage may damage the printing and the can and serve as a nucleus for corrosion.

Make sure the pallets are covered appropriately.

Page 5

Store the pallets with the cans on a flat and symmetrical surface in order to keep the cans from collapsing.

7.2 High Humidity

High humidity may cause cans to sweat, producing corrosion on the outside. Storage rooms close to production halls, must be effectively insulated so that the steam and high humidity in the latter will not cause external corrosion of the cans being stored.

One must also provide appropriate airflow and ventilation, especially in plants that are close to the sea, where there are problems of high humidity and salt.

7.3 Storage Temperatures

Storage temperatures exceeding 3035, the result of exposure to the sun in an unroofed place, accelerate the corrosion process and shorten shelf life. In the case of filed cans, the increased internal pressure, especially for highly carbonated beverages, such as colas, lemon-lime drinks, soda, etc, will warp the ends.

8. Stress Corrosion of Easy-Open Aluminum ends

8.1 Easy-open ends on beverage cans are made of a Aluminum metal that is coated on both sides. The most sensitive zone is around the score, which is also the thinnest part of the end.

The main characteristic of this phenomenon is spontaneous rupture of the end, causing the product to spill on other cans packed on the same tray or pallet.

Later the process is apt to result in severe damage as a result of secondary external corrosion of the can body.

8.2 Causes

The main cause of this phenomenon is an accumulation of moisture and water left behind on the end by the filling process.

The moisture accelerates corrosion around the groove, which is not protected by the coating. The groove is weakened and cracked, after which the end bursts opens because of the internal pressure.

Other factors accelerate this process, including:

8.2.1 A build-up of moisture as result of condensation of water vapor from the air on the cans (extreme sweating)

Page 6

8.2.2 The exposure of the can to a corrosive environment on the filling lines, such as excessive acidity of warmer.

9. Preventive Methods

The most important actions to prevent corrosion are as follows:

9.1 Thoroughly rinsing the end of the can with clean water immediately after seaming and again after it leaves the heater (preferably with de-ionized water) to eliminate residues of corrosion-promoting substances.

9.2 Completely drying the end surface before shrink-wrapping, by forcing pressurized air through five nozzles for 10 seconds over the entire surface of the end.

9.3 Make sure that the temperature of the can when it leaves the heater is above the dew point, and preferably above 25C.

9.4 As noted in 7.3, storing the cans in a covered area, at a temperature that does not exceed 30C35C.

Higher temperatures, resulting from exposure to the sun, accelerate the corrosion process and may increase the pressure inside the can, which in the case of highly carbonated beverages may cause the end to burst.

10. More

10.1 Keep the heater water pH at the range 6.87.8; the recommended range is a pH of 7.27.5.

A pH above 7.9 is considered corrosive. Alkaline water accelerates external corrosion of aluminum end, causing the metal to turn dark and damaging the printing on the outside.

10.2 Conveyor-belt lubricant recommended by Caniel, manufactured by the German Henkel Corporation (dilute the soap 1:30 and apply it using pumps and Henkel spray nozzles).

This is meant to avoid the use of soap that contains residues of metals and/or other corrosion-promoting substances.

10.3 Avoid presence of corrosion-promoting equipment or parts, made of brass or copper, near the can conveyors on the filling and packaging line.

10.4 Leave spaces between the pallets in the finished-product warehouse to permit better ventilation of the cans.

Page 7

Failure to follow these recommendations may lead to stress corrosion accompanied by severe damage caused by secondary corrosion on the outside of the cans.

11. Water Treatment

Treating the water serves the following objectives:

a. Guaranteeing uniform water composition throughout the year b. Remove colloids and foreign matter from the water c. Remove uncharacteristic colors d. Remove uncharacteristic flavors and odors e. Reduce alkalinity f. Prevent microbial contamination

11.1 Standard Water Treatments

The most common method of treatment is with hydrated lime. Adding this to alkaline water reduces alkalinity because dissolved calcium and magnesium salts form insoluble precipitates.

Ca(HCO3)2 + Ca(OH)2 2 CaCO3 + 2 H2O Soluble insoluble

MgCO3 + Ca(OH)2 Mg(OH)2 + CaCO3 Soluble insoluble

If alkalinity comes from sodium carbonate, it is also necessary to add calcium chloride.

Na2CO3 + CaCl2 CaCO3 + 2 NaCl insoluble soluble

11.2 Adding Coagulants

Coagulant treatment is meant to cause organic substances, foreign matter, and calcium, magnesium, and sodium salts to precipitate out; the iron salt forms a colloid to which these materials adhere and precipitate from the solution.

The most common method is to add ferrous sulfate and calcium hydroxide.

FeSO4 + Ca(OH)2 Fe(OH)2 + CaSO4

Page 8

11.3 Chlorination

Active chlorine must be added to the water to disinfect it and remove all dissolved organic matter that might cause unpleasant odors and aftertastes. The chemical process is as follows:

Cl2 + H2O HCl + HOCl oxidant

For effective oxidizing, the concentration of free chlorine, expressed as Cl2, must be at least 0.6 mg (but no more than 2 ppm to prevent corrosion), with a reaction time of more than 2 hours.

11.4 Filtration (sand and activated carbon)

Filtration with activated charcoal eliminates the chlorine left from the chlorination process. Activated carbon catalyzes the following reactions:

activated Cl2 + H2O 2 HCl + O

charcoal

At the end of the process, sand filtration removes the precipitates formed by the lime treatment and chlorination.

11.6 Ion Exchanger

11.6.1 Whenever nitrate (NO3) concentration exceeds 10 ppm, an anion exchanger or selective nitrate exchanger must be installed.

O

CO2

act. charcoal

organic matter

Organic oxidation products

Page 9

11.6.2 Whenever iron concentration exceeds 0.1 ppm, cation exchanger must be installed.

Another form of water treatment used by soft-drink industry is reverse osmosis (RO), which can eliminate 90%95% of all dissolved solids, such as carbonates, chlorides, and sulfates, and nearly 100% of dissolved organic substances with a molecular weight above 100, and of course total microbial filtration.

The method involves passing the water through cellulose acetate or polyamide membranes.

The table illustrates the results of reverse osmosis treatment:

Before R.O After R.O Totaled dissolved solids 205 < 50 Alkalinity 77 < 15 Chlorides 20 < 5 Total hardness 134

Page 10

Recommended Water Quality for Filling Cans

Parameter Max. recommended concentration, mg/L

Unit

1. Acidity 0 ---

2. Total alkalinity 50 CaCO3

3. Arsenic 0.01 As

4. Barium 1.0 Ba

5. Zinc 1.0 Zn

6. Chlorides 50 Cl

7*. Copper 0 Cu

8. Cyanides 0.01 CN-

9. Fluorides 0.8 F-

10. Hardness 200 CaCO3

11*. Iron 0.1 Fe

12. Lead 0.05 Pb

13. Manganese 0.05 Mn

14. Mercury 0 Hg

15. Nitrates 10 NO3

16. COD from KMnO4 4 hours at 27C Oxygen demand

17. Coliforms 0

18. Total count

Page 11

12. Soft drinks can be classified as follows:

B E V E R A G E S

Carbonated (CO2) noncarbonated

Natural/reconstituted Flavored drinks Natural/reconstituted Flavored drinks

nonalcoholic alcoholic alcoholic nonalcoholic alcoholic alcoholic (natural) (added) (natural) (added)

12.1 Hot-Filling

Hot-filling stages:

a. Filling with juice at a temperature of up to 92C b. Injection of liquid nitrogen c. Seaming d. Cooling

The system is based on hot filling and developing positive pressure by injecting liquid nitrogen into the headspace of the can. The liquid nitrogen is injected before the can is seamed.

The nitrogen vaporizes after seaming, creating internal pressure, which is necessary to keep the cans from collapsing after cooling.

This method produces juices or beverages with positive pressure in the can. Because the volume ratio of liquid to gaseous nitrogen is 1:690, it take only a very small amount of liquid nitrogen to do the job.

Page 12

The wrong amount of nitrogen may cause one of the following:

a. Excessive pressure, buckling of the end or bottom b. Low pressure cans are sensitive to blows, producing creases and cracks in the

inner coating and then corrosion.

The internal pressure at 25C should not be less than 1.3 bar.

12.2 Cold-Filling

Cold filling involves the following stages:

12.2.1 Cold-filling with juice at a temperature of up to 25C

12.2.2 Injection of liquid or gaseous nitrogen and seaming, preserving the low oxygen level in the headspace. If gaseous nitrogen is used, it does not provide any reinforcement to the can.

12.2.3 Pasteurization and chilling (in this method, the pasteurization temperature must be defined for each type of beverage). During pasteurization or cooling make sure to use low-alkaline and chloride- sulfate-free water.

During pasteurization and cooling the pH of the water should be 6.87.8, and preferably 7.27.5. A pH above 7.9 is considered to be corrosive.

Alkaline water accelerates external corrosion of the aluminum end and may damage the printing. The disadvantage of this method is the long pasteurization time, which detracts from the organoleptic qualities of the product. If gaseous nitrogen is used the can will have relatively low mechanical strength.

Blows to the sides of the can may impair the quality of the inner coating and accelerate internal corrosion.

Page 13

13. Raw Materials

13.1 Water

Because water is the main ingredient in beverages and constitutes about 86% of the finished product, the water must be of extremely high quality, clear, without turbidity, odorless, and tasteless.

The level of dissolved minerals should be minimal, especial with regard to nitrates. Nitrates should not exceed 10 milligrams a liter; iron should not exceed 0.1 milligrams per liter; sulfur dioxide should not exceed 5 milligrams per liter. Minimum levels of chloride, sulfates, and dissolved air are also important.

13.2 Acidulants

Acidulants in beverages serve three purposes:

a. They give the drink its characteristic sour taste. b. The cut the sweetness of the sugar. c. They serve as a preservative.

The most common acidulants in use are citric acid for fruit-based drinks, phosphoric acid for colas, tartaric acid for grape juice. The acid in beer and in natural or reconstituted juices is natural, the result of the fermentation process (beer) or the properties of the raw material (juices).

13.3 Antioxidants

Antioxidants such as ascorbic acid are added to some drinks. Their purpose is to react with oxygen and prevent oxidation of the ingredients.

13.4 Carbon Dioxide (CO2)

This gas is added to beverages during the carbonation process (carbonated beverages only). Carbonation means saturating the liquid with carbon dioxide, which gives the beverage a characteristic flavor, serves as a preservative, prevents the growth of bacteria, and slows the rate of corrosion in the can. High-quality gas (low sulfur level) is important. The amount of CO2 in the product is expressed as volumes of CO2.

On this basis, carbonated beverages can be divided into three groups:

a. CO2 volume greater than 3.5: colas, soda, tonic, ginger ale b. CO2 volume 2.53.5: beer, lemon-lime drinks, orange drink c. CO2 volume 1.0-2.5: apple juice, grape juice, strawberry, raspberry

The CO2 volume is the ratio between the volume of the gas and the volume of liquid.

Page 14

The upper limit for carbonation volume is 4. The internal pressure at 21C must never exceed 60 PSIg.

13.5 Flavorings

Flavorings are the ingredients added to the beverage that give it its characteristic taste. Food coloring, acidulants, and preservatives are usually added as well.

Flavorings can be classified as follows:

a. Alcoholic extracts b. Nonalcoholic extracts c. Concentrates d. Natural juice concentrates e. Emulsions f. Flavored syrups

13.6 Food coloring

Food colorings are supplied in the form of powder, paste, or liquid.

13.7 Preservatives

Preservatives are meant to prevent spoilage caused by microbial growth. The most common preservative is sodium benzoate, which is tasteless and odorless at the appropriate concentrations and effective against the growth of mold, fungus, and bacteria. The recommended concentration is 150200 ppm. It is effective in sour products (the non-ionized form is the active form).

Preservatives should not be added to products, like cider and beer, that are pasteurized to kill bacteria.

13.8 Sweeteners

Most sweeteners are sugar-based products that provide sweetness and add flavor and calories to the beverage. There are also artificial sweeteners for diet drinks.

The most common sweeteners in use are as follows:

a. Crystalline sugar/sucrose b. Glucose c. Sugar syrup d. Dextrose e. Sorbitol f. Artificial sweeteners

Page 15

For canned beverages, all these sweeteners must be totally free of sulfur dioxide.

14. Carbonated Drinks: Production and Filling

The manufacturing and filling processes for carbonated beverages must take account of the shelf life of canned drinks.

Soft drinks, unlike other canned food products, are extremely corrosive. This generally causes iron from the walls and bottom of the can to be dissolved by the product. A high iron-ion concentration in the beverage (more than a few milligrams per liter) may give some products an aftertaste. So care must be taken during the production, filling, and seaming processes to assure the following: a negligible concentration of iron ions in the raw materials, removal of corrosion-promoting substances such as nitrates and sulfur dioxide from raw materials and azo dyes from the ingredients added, and minimal oxygen in the product and headspace during the manufacturing process.

Handle the cans Carefully, without collisions that might damage the special coating of the can.

Storage of both empty and full cans in an appropriate atmosphere and temperature.

14.1 Preparing the Syrup

a. Preparing the beverage ingredients, such as acidulants, flavorings and aromatic ingredients, and preservatives by continuous mixing with water

b. Preparing the sugar syrup by mixing crystalline sugar (sucrose) with water It is important to use sugar that is 99.9 percent pure to avoid aftertastes, heavy-

metal contamination, etc.

c. Mixing the two syrups together to create the final syrup, which has a concentration of 5060 Bx.

Make sure that the mixing vats are made of stainless steel and that the syrup and water never come into contact with iron pipes or containers.

The acidulants in common use bind iron ions relatively easily and may therefore cause primary contamination of the beverage with iron ions, which has far-reaching implications for creating a strong aftertaste and shortening the shelf life of the beverage.

Page 16

14.2 De-aeration

In order to reduce the amount of air in the beverage to a minimum, to inhibit the rate of corrosion and increase the shelf life of the canned beverage, the water needs to be de-aerated before the beverage is prepared.

Applying a strong vacuum to a vat while water is sprayed through it.

Another method has been developed recently, in which pressurized water is sprayed into a vat containing CO2. The gas removes the air from the water, leaving a final concentration of air in the water of about 0.50.8 ml by volume per 330 cc of beverage.

14.3 Carbonation

There are several ways to carbonate beverage. Most of them are based on mixing the syrup and water in fixed ratios, depending on the type of beverage, then chilling the product to nearly 0C and injecting CO2 (see Figure 2).

The amount of CO2 injected into the beverage depends on several factors:

14.3.1 The contact surface between gas and liquid: the larger its area, the greater the efficiency of absorption

14.3.2 The contact time between the gas and liquid

14.3.3 The absolute pressure of the gas-liquid system

Water Syrup

Mixer

Cooler

Filler Can

Page 17

14.3.4 The temperature of the liquid: the colder the liquid, the greater the solubility of gas in it

14.3.5 The type of product: products with a higher sugar level can dissolve less CO2 than products with less sugar

14.3.6 The purity of the CO2: any contamination by another gas and especially air will cause displacement of the CO2 (for example, one volume of dissolved air in the beverage will displace 50 volumes of CO2)

At the end of the carbonation process the temperature of the product must be 0C2C. This temperature will preserve the desired carbonation level until filling and seaming.

14.4 Moving and Rinsing Empty Cans

When empty cans are being moved on the conveyor, make sure that they do not bump against one another and are not damaged by the conveyor equipment.

Mechanical impact can damage the coating and expose the underlying metal; thereby increasing the rate of corrosion while the product is being stored. Before the filling stage, the cans should be rinsed in cold water and turned upside down during or after rinsing. To maintain a low filling and seaming temperature, avoid rinsing in hot water or steam. Be careful to remove residues of the rinse water and any foreign objects from the can.

14.5 Filling Process

For carbonated beverages, the cans must be filled at a temperature below 4C. Hence the carbon cooler should be close to the filling unit and the pipe between the two units should be properly insulated.

This will preserve the appropriate level of carbonation for the beverage and reduce the risk of foaming when the can emerges from the filling machine.

14.6 Foam Breaker

Highly carbonated beverages, such as colas, lemon-lime drinks, and drinks with a large amount of dissolved air, are liable to foam after filling when the canned is released to atmospheric pressure. Because the foaming creates an emulsion of air and product, there is a danger that this air will be trapped inside the can when the canned is seamed. To avoid this, a unit is installed right before the cans enter the seaming machine to inject CO2 into the headspace of the can, so as to break up the bubbles and eliminate the trapped air. Seaming machines for soft drinks are equipped with a

Page 18

device for spraying CO2 into the headspace so as to eliminate the air trapped in it. The foam breaker mentioned above is one such device.

Another device, located close to every seaming head in the seaming machine, forces the air out of the headspace during the actual seaming process.

The maximum permissible amount of air in a can at the post-seaming inspection is 2 ml of air in the headspace and one ml of air absorbed or dissolved in the product.

15. Heating or Pasteurizing Cans

15.1 Heating Carbonated Soft Drinks

Carbonated soft drinks that are filled at a low temperature must be heated to raise the temperature of the beverage to the ambient temperature for that season. This is necessary to prevent sweating caused by the condensation of water vapor from the air onto the outside of the cold canned.

In summer the cans should be warmed to 30C; in winter, to 20C25C.

This step must be carried out efficiently and carefully. Inefficient heating will cause condensation of water vapor on the outside of the can and speed up external corrosion processes. Temperature above 30C for highly carbonated beverages such as colas, lemon-lime drinks, and soda will create high pressure inside the can and may warp the cover if the pressure exceeds 6 atmospheres.

The process involves spraying hot water, passing through a hot water warmer, or passing through a steam channel.

15.2 Pasteurizing Carbonated Natural and Reconstituted Beverages

Because they are marketed without preservatives, beverages such as cider and beer must be pasteurized. The pasteurization temperature ranges from 60C to 70C, and the time varies, both of them as a function of the product type and composition. Because the pasteurization temperature is high, insure a low carbonation level and large headspace, to avoid attaining a pressure of 6 atmospheres during the pasteurization process.

When pasteurization or heating is over, air must be blown on the cans, while turning them over, in order to dry them completely before packaging.

Cans that are still wet when they reach the packing trays will cause external corrosion and rust during storage.

Page 19

16. Inspection of Filled Cans

After the pasteurization stage and before the packaging stage the filled cans must be inspected in order to guarantee their quality at the time of packaging and to detect any flaws that caused leaks during the filling process. The standard filling inspection is done using x-rays detector.

If the fill height is less than the calibrated range the canned is rejected automatically.

This method rejects cans that were not properly seamed and remained without ends.

Another but less common method is to weigh the cans. The disadvantage is the need to calibrate the sensor for each different type of beverage, because each drink has its own specific gravity.

17. Production Code Marking

The production code is marked on cans, before filling process or before packing.

There are several standard methods:

Contact methods

1. Printing a visible code on the side or bottom of the can 2. Printing an invisible (UV) code

Non-contact methods

1. Laser engraving 2. Inkjet printing, usually on the bottom of the can

18. Packing

The standard package is 24 cans in a tray with or without shrink-wrap. Cans must be absolutely dry when packed. Damps cans are liable to rust during storage, especially when packed in shrink-wrapped trays, which create a closed corrosive cell if the cans are still wet or damp.

19. Storage

Cans should be stored on a flat and symmetrical horizontal surface. An uneven surface may cause the cans to collapse.

Page 20

20. Quality Control during the Manufacturing Process

The parameters that determine the shelf life of the product must be applied during the filling process, along with strict attention to appropriate recording to permit product tracking.

20.1 Filling Tests

Check the uniformity of the fill volume of the filling-machine heads at the start of each production day. To do this, take a can from each fill head and check its weight or volume. The deviation among the fill heads should not exceed 5 ml; the minimum fill volume is 330 ml. specific gravity of the beverage must be taken into account.

20.2 Testing for Air in the Headspace and in the Beverage

This test is performed using a Zahm and Nagel device (Figure 2). To run it, fill the glass burette (No. 1) with a solution of 20%30%. potassium hydroxide or sodium hydroxide. Place the canned on the stand (No. 5) and lower the piercing unit (No. 21) into the can, with the valve (No. 30) closed. Ignore the pressure reading on pressure gauge.

Open the valve (No. 30) until the pressure on the gauge falls to zero. Shake the device and the glass burette well until the soda takes up all of the CO2, the volume of the trapped air bubble remains constant, and the pressure-gauge reading is steady. Use this reading to calculate the carbonation. The bubble of air trapped in the burette after the valve is opened corresponds to the amount of air in the headspace.

Continue opening the valve (No. 30) and shaking the can until the pressure drops below 0.5 atmospheres. The amount of air added to the original volume of the bubble indicates how much air was absorbed by the product.

This test should be run once an hour, on one can from each fill head after the heating stage.

The maximum amount of air in the headspace should be 2 ml; air absorbed by the product should not exceed one ml. More than 2 ml of air in the headspace indicates improper removal of air from the headspace by the CO2 injection system, in the seaming and defoaming stages.

Too much air in the product is the result of inefficient removal or nonremoval of air by de-aeration of the water.

To check the efficiency of the CO2 injection when the can is seamed, take a can from each seaming head, fill them with 330 ml of saturated saline solution, and seam them.

Page 21

The air measurement device will indicate the amount of air trapped in the headspace. If this exceeds 2 ml, regulate the flow of CO2 during injection and repeat the test.

Remember that the CO2 flow must be laminar. A turbulent flow is apt to cause precisely the opposite phenomenon, namely the introduction of air into the headspace instead of its removal.

20.3 Fill-Temperature Test

The appropriate fill temperature is between 0 and 4C. This value is important, because higher fill temperatures mean an increased tendency to foam, which carries a risk of underfilling and infiltration of air. The temperature should be checked every 30 minutes.

20.4 Carbonation Test

The carbonation is tested along with air by reading the maximum pressure after the can has been shaken once and comparing it to the pressure in the can after the air has been removed. The temperature of the beverage yields the carbonation value, expressed as CO2 volumes, which is the ratio between the volume of CO2 gas and the volume of beverage.

20.5 Testing the Temperature at the waemer Exit

To prevent condensation of water on the sides of the can, it is important that it leave the warmer at a temperature higher than the ambient temperature for the season.

In summer, the temperature should be a maximum of 30C; in winter, 20C25C. Make sure that the temperature does not exceed 30C.

In highly carbonated beverages such as colas and lemon-lime drinks, high temperatures may produce an internal pressure > 6 atmospheres, which could cause warping of the aluminum end.

Run this test on two or three cans every hour.

20.6 Checking the Calibration of the Weight Gauge or Fill-Height Gauge

To do this, prepare standard cans filled with volumes of 330 ml, 325 ml, and 335 mm, and run them through these gauges. The can with a fill volume of 325 ml should be rejected, while the other two should pass. Run this test two or three times every shift.

Page 22

20.7 Checking for the Presence of the Code

Two or three times every shift one should take a can off the line and check whether the code can be read for identification purposes, as required by Israeli standard 1145.

20.8 Seaming Tests

Attaching the end to the can is a mechanical operation that involves the rotational motion of a set of cylinders that produce the double seam.

1. Actual overlap 2. Body hook 3. cover hook 4. Seam length 5. Seam thickness (including free space) 6. Depth of depression

21. Seaming Test

The seaming test is usually divided into two types:

a. Destructive test b. Visual test

A. Destructive test

The destructive test is run at the start and in the middle of each shift. For each test a can is taken from each head of the seaming machine and three points along the end seam are tested.

The parameters listed in 20.8 above are measured manually, using computerized systems such as Seametal.

Correct seam thickness is of utmost importance to prevent gas lose and corrosion inside the double seam.

The maximum recommended seam thickness is three times the thickness of the metal plus twice the thickness of the body metal plus 0.006.

In case of deviations from the recommended dimensions, but the overlap, seam thickness, and flange are acceptable, the seam will be considered to be acceptable.

See the information bulletin, Recommended Seam Dimensions for Aluminum End B64 206 on Caniel Steel Cans.

Page 23

B. Visual check

A visual check should be performed once an hour, by feeling the seam and inspecting its soundness by eye, looking for cutover, beads, or general damage.

Page 24

Appendix A Manufacture of Carbonated Soft Drinks

Cans

deplletizer

Rinser

Filling machine

foam breaker

Injection of CO2 during

closure

Closing machine

warmer and dryer breaker

Full-height gauge or

scale

Code printer

Packing machine

Palletizer machine

Crystalline Sugar

Sugar Solution

Filtration

Concentrated Syrup

Dosing

De-aerator Cardboard Trays

Shrink- Wrap

Warehouse for canned

carbonated beverages

Treated Water

Water treatment and

filtration

Raw Water

CARBO COOLER

Acidulates / Flavors /

Preservatives

Additives

Page 25

Appendix B