Food preservation and packaging: cans versus plastic pouches

Food preservation and packaging

Most of us grew up quite safely on canned foods after our mothers were assured that modern packaging processes using cans preserved most of the key nutrients in foods and also represented one of the most affordable and convenient ways to get those essential nutrients into their broods’ alimentary canals. Today food that once only came in cans now also comes in plastic pouches and the latter has quietly turned into one of the fastest growing new trends in packaging and preserving food and drink. The question that remains is: which is best?

Steel and aluminium versus plastic

Modern cans are made of either aluminium or 98.5% sheet steel with a thin coating of tin. Most canned food comes in steel cans, while drink cans are more likely to be aluminium.

Pouches are mostly made of layers of polyester, nylon, aluminium and polypropylene. As many as five layers of different types of plastics and aluminium foil are laminate together to make certain pouches.

There are pros and cons associated with both products as can be seen below.

Steel or aluminium cans

• • Steel cans can easily and successfully be re-used and recycled which, in a way, negates the negative influence of greenhouse gasses produced when manufacturing them.

• • Some steel cans, in some countries, have linings that include a synthetic compound called bisphenol-A (BPA). The latter may end up in small quantities in food and beverages and has been linked to various health problems and childhood obesity. However, a lot of canned food brands have already started using packaging lined with a BPA alternative and are intent on eventually phasing out the use of BPA all together.

• • Canned food is cooked twice, once before and again after canning, at more than 212 degrees and some people find that this influences the taste of some canned foods but not all.

• • Canned foods can last weeks, months and as methods improve, years.

• • Some cans are more difficult than others to open.

Plastic pouches

• • Despite lack of evidence that the construction of plastic pouches allows plastics or chemicals to leach into food, and although pouches can be microwaved or submerged in a pot of boiling water, it is recommended that food be taken out of the pouch before cooking or heating to be doubly safe.

• • Food pouches, due to their complex construction and the soft plastics they are made of, leave a bigger carbon footprint than cans. Although much of the plastic, such as clear polyethylene, can be recycled, most of the rest can’t and therefore end up in landfills.

• • Food pouches weigh less and take up less space than cans, which is a bonus for manufacturers who save on transport, shipping and handling and for retailers but not necessarily for the consumer. And, although plastic is cheaper than metal, the cost of plastic resin has risen dramatically and these extra costs will, as usual, be passed on to the consumer.

• • Thin food and drink pouches are very versatile, easy to use and practical, For example, small pouches, not bottles, of water are being manufactured for athletes and people exercising. Also, one of the latest “mommy helps” consists of pouches of baby food filled with fruit puree and vegetables that babies can suck from the container.

• • From a marketing and printing prospective, plastic pouches are an ideal medium on which to print eye-catching graphics.

• • Taste wise some people prefer food in pouches because they perceive the food to be fresher and of a better quality. This may be due to the cooking process which is much shorter in pouched food than in canned food.

• • Pouched food has a shorter shelf life than canned food.

• • Some consumers prefer pouches because they are easier to open than cans.

Conclusion

Analysts report that canned or preserved food is experiencing volume declines in South Africa. They add that the high cost of raw materials and resulting higher unit prices per item are to blame and that South African consumers are increasingly attracted to products that retail at a lower unit price. They also report that although stand-up pouches in canned or preserved food have become very successful and, should developments continue, their benefits may soon outweigh those of metal food cans, price is still a problem and most consumers find them too expensive to buy.

So, that’s that. What it boils down to is that you as the consumer, after carefully weighing up all the pros and cons, have the last say. The choice is yours!

 

Sources
Albright, M. Plastics: bye-bye bottles and cans, hello pouch packaging. Retrieved from: http://www.tampabay.com/news/business/retail/plastics-bye-bye-bottles-and-cans-hello-pouch-packaging/1232103
Canned/Preserved food packaging in South Africa. 2014. Retrieved from: http://www.euromonitor.com/canned-preserved-food-packaging-in-south-africa/report
Kenworthy, A. 2014. Cans versus pouches. Retrieved from: http://www.good.net.nz/article/2014/02/cans-versus-pouches