Vacuum Packing - Food Packaging Technology

Vacuum Packing Technology
Introduction - History - Requirement - types - machines- containers - vacuum bags types - advantages - disadvantages - comparison

1. FOOD PACKAGING TECHNOLOGY VACUUM PACKAGING

2. INTRODUCTION Removal of air from the package prior to sealing The intent of vacuum packing is usually to remove oxygen, but in fact air is removed completely Paves the way to limit the growth of aerobic microbes Prevents the evaporation of volatile components.

3. HISTORY Dates back to the period before World War II In France, air was removed from rubber latex bags and sealed which slightly increased the shelf life of the food product. After World War II, commercialization of plastics opened the door for vacuum packing. In 1950, as a commercial initiative whole turkeys were packed in plastic bags after removal of air.

4. NEED FOR VACUUM PACKAGING 21% O 2 in air Favorable for most microbes O 2 highly reactive Reacts with organic compounds causing undesirable changes in sensory attributes.

5. TYPES OF VACUUM PACKAGING MACHINES External sealers Single Vacuum Chamber Machines Double Vacuum Chamber Machines Rotary belt type vacuum sealer (Rolling vacuum sealer) Automatic Belt Vacuum Chamber Machines Thermoforming Vacuum Packaging Machines

6. EXTERNAL SEALERS Involves a bag being attached to the vacuum-sealing machine externally. The machine will remove the air and seal the bag Complete process occurs outside the machine. Easy to operate homescale

7. SINGLE VACUUM CHAMBER MACHINES The whole setup should be kept inside the lid like apparatus The chamber has a heat seal inside, which seals the bag after removal of air. Can seal liquids due to equal pressure in the chamber and the bag which eliminates spilling

8. DOUBLE VACUUM CHAMBER MACHINES Has two chambers but same as single chamber in operation After sealing 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 is removed.

9. ROTARY BELT TYPE VACUUM SEALER Same as the double vacuum chamber machine More convenient as the belt rotates automatically while the bags are placed to the sealing bar The sealed bags are automatically unloaded The packaging plate of the machine is also adjustable

10. AUTOMATIC BELT VACUUM CHAMBER MACHINES The product travels on the conveyor belt and automatically positioned in the machine, the lid is closed and the air gets removed and finally sealed. The chamber is refilled with air by the automatic opening of a vent to the outside Suitable for packaging of large items.

11. THERMOFORMING VACUUM PACKAGING MACHINES Form-Fill-Seal type Products are loaded into the thermoformed packs and sealed under vacuum PET is the most commonly used thermoformed plastics due to easy molding and high strength High operation speed

12. CONTAINERS FOR VACUUM PACKAGING Vacuum bag packaging is the most common form of vacuum packaging Bags are available in multiple sizes, thicknesses, and types to accommodate a variety of products Made from polypropylene, polyethylene, nylon and polyester The most common vacuum bag thickness is 0.07 mm

13. TYPES OF VACUUM BAGS Standard vacuum bags Channeled / embossed vacuum bags Vacuum zipper bags Notched vacuum bags High barrier shrink vacuum bags

14. STANDARD VACUUM BAGS Smooth and available in multiple thicknesses and sizes The most common thickness is 0.7 mm Ideal for most products unless the product has sharp edges or corners such as bones or pointed metal objects.

15. CHANNELED / EMBOSSED VACUUM BAGS The surfaces of the bags are textured Restrict air passage into the bag Have high O 2 barrier Widely used on most residential use vacuum sealers

16. VACUUM ZIPPER BAGS Contains zipper in one end of the bag Facilitates easy opening and closure of bag Avoids tearing of bag to take out the product and so it can be reused Commonly used in packaging of processed meat and meat products.

17. NOTCHED VACUUM BAGS These bags are smooth and clear Have an easy to open tear notch Size of the bag range from 4 to 12 inch widths.

18. HIGH BARRIER SHRINK VACUUM BAGS Contain multi layers meant for preventing oxygen permeability High shelf life extension among vacuum bags Commonly made of Polyvinylidene chloride (PVDC) and Ethylene vinyl alcohol (EVOH)

19. EFFICIENCY OF VACUUM BAGS Determined by measuring how much cm 3 of oxygen penetrates through 1 m 2 of material over a 24 hr period For standard bags it is 100 cm 3 For PVDC it is 10 cm 3 For EVOH it is 1 cm 3 Lower the penetration value higher will be the efficiency

20. ADVANTAGES OF VACUUM PACKAGING Elimination of oxidation Preserves delicate oils Prevents freezer burn Maintenance of natural moisture Prevents microbial contamination Elimination of chemical preservatives

21. DISADVANTAGES OF VACUUM PACKAGING Risk of anaerobic bacterial growth Chance for loss of integrity of food while force suctioning of air

22. TYPICAL SHELF LIVES OF VACUUM PACKAGED PRODUCTS PRODUCT NORMAL REFRIGERATED LIFE VACUUM PACKED REFRIGERATED LIFE Fresh Fish 1-2 days 1 week Smoked fish 1-2 weeks 6 - 12 weeks Fresh Beef 1-2 weeks 6 weeks Fresh Pork 1-2 weeks 2 weeks Fresh Poultry 1-2 days 1 week Sliced Meat 1-2 days 6 - 12 weeks Pizza 1-2 days 1 week Cheese 1-2 weeks 6 - 12 weeks