Vacuum Packing SUBMITTED BY ANUROOP R NAIR NANDU SURESH CHINMAI CHANDRAN VACUUM PACKAGING • Vacuum packaging is a method of packaging that removes air from the package and hermetically sealing it. WHY VACUUM • The single most important reason for creating a vacuum in food packaging is to remove oxygen from around the thing that we are going to store AIM OF VACUUMPACKAGING To extend the shelf life of foods and, with flexible package forms to reduce the volume of the contents and package BENEFITS OF VACUUMPACKAGING . It eliminates oxidation. .It preserves delicate oils. .It maintains natural moisture .It prevents moisture contamination. .It prevents freezer burn. ELIMINATING OXIDATION . . Certain enzymes that are naturally present in food are known as oxidizing enzymes. These enzymes catalyze (speed up) chemical reactions between oxygen and food components, and this leads to food spoilage. There are many oxidizing enzymes that can cause darkening in sliced vegetables are catalase and peroxidase. . . For example banana and apple quickly show signs of oxidation by browning. Vacuum packing eliminates contact with the air and therefore eliminates oxidation. PRESERVING DELICATE OILS • Rancidification is the process which causes a substance to become rancid, that is, having a rank, unpleasant smell or taste. • It is due to the Autooxidation of fat using oxygen. • Vacuum oil, packaging prevents oxidation and preserves delicate PREVENTING FREEZER BURN . Freezer burn is the loss of flavor and texture of food due to oxidation, dehydration, and slow bacterial growth. . These process all need oxygen to occur. . Vacuum packing eliminates oxygen and therefore freezer burn MAINTAINING NATURAL MOISTURE . we pack or wrap food is to keep it from drying out :air causes . moisture to evaporate. By removing the air with vacuum packing the foods natural moisture is maintained along with all its flavour and texture. STOPPING MOISTURE CONTAMINATION . . Dehydrated foods, unless they are kept in an airtight container quickly spoil as moisture in the air softens them Vacuum packing these types of foods in useable quantities is far superior in maintaining the natural textures and flavours as it not only removes the air but the moisture it carries as well. TYPES OF VACUUM PACKING MACHINES . EXTERNAL BAG MACHINES . VACUUM CHAMBER MACHINES EXTERNAL BAG MACHINES • External vacuum sealers involve a bag being attached to the vacuum-sealing machine externally • The machine will remove the air and seal the bag,which is all done outside the machine. • A heat sealer is often used to seal the pack. HEAT SEALER • A heated surface presses the bag closed while applying sufficient heat to slightly melt the plastic of the bag. • This melting is carefully controlled so that it creates an airtight seal that can't be pulled apart. • Once a vacuum bag has been sealed like this, theonly way to reopen the bag is to cut it open beneaththe seal. • A good air-tight seal depends on three things • Bag Thickness: Thicker bags need more heat that thinner ones. A bag that is too thin may just burn through whereas one that is too thick will not seal properly. • Bag Material: Vacuum bags are made from a polyamide(PA) air impenetrable exterior and a poly-ethylene (PE) food approved interior. The relative proportions of each will affect the amount of heat needed to make a good seal. • Number of Bags Being Sealed: If you are sealing a number of bags one after another then the bag sealer on the machine itself will heat up. This means that by the time you get to the second or third bag the machine maybe too hot and just burn through the next bag. The machine will remove the air and seal the bag, which is all done out side the machine. VACUUM CHAMBER MACHINE • These machines resemble a stainless steel box into which them vacuum pouch and contents are placed and the lid closed over them. The entire chamber is then vacuumed and the pouch is heat sealed. SINGLE VACUUM CHAMBER MACHINES • Single chamber sealers require the entire product to be placed within the machine. • Like external sealers, a plastic bag is typically used for packaging. Once the product is placed in the machine, the lid is closed and air is removed. • Then, there is a heat seal inside the chamber that will seal the bag, after sealing the bag the chamber is refilled with air by the automatic opening of a vent to the outside. This oncoming pressure squeezes all remaining air in the bag. The lid is then opened and the product removed. Chamber sealers are typically used for low-to medium-volume packaging, and also have the capability to vacuum seal liquids. DOUBLE VACUUM CHAMBER MACHINES • Double chamber sealers require the entire product to be placed in a plastic bag within the machine. Once the product is placed in the machine on the seal bar, the lid is closed and air is removed. • Then a seal bar inside the chamber seals the product in the bag, after sealing the bag the chamber is refilled with air by the automatic opening of a vent to the outside. This oncoming pressure squeezes all remaining air in the bag. The lid is then opened and the product removed. • Double chamber sealers are typically used for mediumvolume packaging, and also have the capability to vacuum seal liquids. The lid generally swings from one side to another, increasing production speed over a single chamber model. Double chamber vacuum packaging machines generally have either spring-weighted lids or fully automatic lids. • Double chamber vacuum packaging machines generally have either spring-weighted lids or fully automatic lids. Double chamber vacuum packaging machines are commonly used for: • • • • • Fresh Meat Processed Meat Cheese (hard and soft) Candy & Chocolate Empty Cans (it's a cool example of atmospheric pressure) FACTORS AFFECTING VACUUM PACKAGING • The success of vacuum packaging depends on • 1 .Characteristics of the food product to be packaged. • 2.Reliability of the packaging machine. and packaging material. APPLICATION OF VACUUM PACKAGING VACUUM PACKED APPLES FRESH MEAT VACUUM PACKED FISH APPLICATIONS OF VACUUM PACKAGING Advantages of Vacuum packaging • • • • • Reduces growth of aerobic microorganisms Reduces evaporation Reduces weight loss Reduces fat oxidation Reduces dryness of product • Reduces freezer burn • Reduces volume for bulk packs Eg. Tea powder, dry leaves etc • Extends the shelf life • Easy to use and maintain the equipment Disadvantages of Vacuum packaging • Cannot be used for crispy products and products with sharp edges • Requires high barrier packaging material to maintain vacuum • Creates anaerobic condition, which may trigger the growth and • toxin production of Clostridium botulinum and the growth of Listeria • monocytogenes. Additional barriers / hurdles are needed to control • these microorganisms • Capital intensive REFERENCE • Paul Newton & Andrew Gillespie "A Practical Guide to Vacuum Packing.pdf "pp no: 2- 42 • Phil Danielson "Recent advances in vacuum sealing techniques"-A Journal of Practical and Useful Vacuum Technology. THANKzz
