Linda: Hi, I'm Dr. Linda Gordon, safefood's Chief Specialist in Food Science. safefood is the all-island body responsible for promoting food safety and healthy eating. This is the safefood food safety podcast series, where we look at the factors that shape the food industry on the island of Ireland.
This episode looks at food packaging and what small food businesses need to think about from materials, to recycling and the environment. Joining us is Ed O'Neill from Teagasc, who is an expert in artisan and specialty foods. He's a packaging technologist and has published papers on chemical migration from packaging into milk and dairy products. Thanks, Ed, for joining us.
Ed: Thank you, Linda, nice to be here.
Linda: Well, I'm going to jump in and ask the most obvious question. What is the purpose of packaging in food?
Ed: Well, technically food packaging may be described as an economic means of providing a product with protection, preservation, information, and containment during filling, carriage, use and sale, and with consideration for the environment. Now that sounds very, very technical but that's the actual official line.
In layman's terms it's designed to protect the goods against hazards during transport and sale, to enhance the sales appeal of a product, which is very, very important. The consumer needs to see the product on the supermarket shelf in order to make that product saleable to the consumer. To ensure the quality of the product, to make sure that what is packed inside remains in a safe and palatable condition. To preserve the contents up to the expected sell-by date, which is absolutely huge because without shelf life, we cannot attain other quality parameters in terms of making it economical to sell the product to the consumer, and so forth.
So shelf life is very, very important. To provide information. This is huge in terms of what do I do with the contents inside, okay? So do I use it in three days of opening, and so forth and so forth? Does it need refrigeration? Does it need freezing, and so forth?
To provide convenience, all right, this is very, very important, especially on the demographics concerned with food packaging. If you're an elderly person, the packaging must be able to be opened and closed readily, resealable, and so forth.
But above all it must be cost effective. It's no use you having a wonderful bottle or a wonderful cardboard box. If the box costs 2.50 or three euro, and the contents inside are only worth one euro. So it must be very, very much cost effective because for the company who's producing the product, they need to make a margin as well.
Linda: So there's really a huge amount to consider there, isn't there?
Linda: And we'll explore some of that as we go along in more detail. But if we don't have the proper packaging for our food what can happen, what are the consequences?
Ed: The consequences are wide and varied. Proper and precise packaging allows you to produce a food product in a quality state, in a palatable state for the consumer. If we don't have proper packaging, then we run down the road of the potential for food contamination, certainly a reduced shelf life, possibly deterioration of the actual food in terms of taste and physical appearance as well.
Linda: What are the most common food packaging materials that you work with in Teagasc?
Ed: Well, that I work with, you know, across the board there's paperboard, plastics, glass and metal. On the glass and plastic side, usually I use the form of bottles, tubs, jars, and so forth. But there are a number of key points that you should realise.
Plastics are wide and varied. They can be engineered to give a range of specific properties, they can be solid, flexible, and so forth. They have many of the beneficial properties of glass in terms of protection and preservation, and they can be manufactured in a huge range of forms, as I've said.
Glass is a wonderful product in terms of it's 100% recyclable, time and time again. Because of the weight of glass, it gives the impression of luxury, so that you're getting something more than just the product inside. Glass can be clear, it's rigid, it's heat and chemical resistant, and glass is actually relatively cheap.
Tin cans are quite common, they're actually made from steel. Metal is a major packaging material, whether it's steel in the form of canning or aluminum in the form of foil, aluminum trays, aluminum cans for beverages and so forth.
And both steel and aluminum are like glass, they are 100% recyclable.
Paper is made mainly from wood pulp. Several layers of paper go together to form carton board, and layers of paper with a central fluted layer is called corrugated board. And this is primarily used for outer packaging such as boxes and so forth. And that's the type of packaging that we use on a day-to-day basis.
Linda: Tell us, Ed, in terms of considering the most appropriate type of packaging material, does it vary for different food types?
Ed: Of course. Things like sauces tend to be packed in glass bottles or jars for hot filling. Hot filling then allows the product to have an extended shelf life. So if I take something like a tomato ketchup, that's heated to approximately 100 degrees Centigrade and it's packed hot in the glass bottles. The bottles are then capped and then inverted and this gives the product a safe food, and this gives a safe food inside the glass jar but it also gives a product extension in terms of shelf life for approximately one year. All right, so matching the actual food product to the packaging is very, very important. For a lot of refrigerated products plastic is convenient and very, very cheap. So we have yogurt tubs in polypropylene containers and so forth, shelf life of somewhere between 25 and 45 days, easy to use, 100% recyclable and so forth. Easy to print an aesthetically-appearing paper is very, very important. Paper is often used as an outer packaging, as a sleeve and so forth over ready meals and things like that. But it's also very, very convenient for, as I said, printing and to provide information for the consumer. It's also used as a boxing material.
Linda: What about the different properties of the different packaging materials? I mean we mentioned earlier on that you've looked at chemical migration from packaging, so what needs to be considered there?
Ed: Basically, the package and the product should be developed in tandem, okay, so that the packaging is suitable for the actual product intended to be used.
Glass has been around since Roman times. It's 100% recyclable, it's rigid, it's chemically resistant, and doesn't impart any flavors to the product within. And it also allows, which is very, very important, it allows the consumer to view the contents inside in clear glass. That's very, very important in terms of the saleability of the product.
Plastic takes many forms. One of the most common is polypropylene used in buckets, tubs, and so forth. Polypropylene, again, like glass is 100% recyclable, but it can be clear, it can be white or opaque, it can be black as well. So this gives an extensive range of uses. It's used primarily in the dairy industry, again, for yogurts, soft cheeses, and so forth. And if you go to the bother of looking at the bottom of a plastic tub, you'll see a little triangle. Now if the number five is there, or the initials PP, it's made from polypropylene. And that's just one of many, many plastics used in food manufacture.
Again, polypropylene, not only dairy but it can be used for mayonnaises, for sauces, and one of beauties of polypropylene is that it's resistant up to 160 degrees Centigrade. So I can hot fill sauces, soups, preserves, jams, and so forth to give them an extended shelf life.
Linda: Obviously you need to then consider your packaging at a very early stage when developing the product and make that decision, rather than developing the product first and then thinking about what packaging I need to use. So what else do food companies need to consider when choosing the right packaging for their product?
Ed: This is quite detailed. The packaging needs to be compatible to the product but also needs to protect and preserve the contents up to the expected sell-by date. When choosing a packaging for your food product, there are three basic considerations. The product details, the make-up of the actual product, the ingredients and so forth, your methods of distribution: do you need to box the package, do we need to put it on pallets and so forth? Does it need to be refrigerated, does it need to be frozen?
And then there's the marketing element. Okay, who's my target audience? What are my demographics and so forth?
So in terms of the product details, are you actually familiar with the product manufacturer? Do you understand the ingredients that go in to make up that product? For instance, does it need protection from light? Does it need protection from moisture? Dry goods such as soups and so forth, they're resistant to microbial influences because there's very little water content there. These dry goods will, if not packed properly, absorb moisture from the atmosphere. Examples will be crisps, sweets, cereals, soups as I've said. They must be packed in a material which prevents the passage of water vapor.
Moist goods, on the other hand, will lose moisture on exposure to the air. They require a package that prevents the loss of moisture. In the case of cheese, a simple wrapping is insufficient as mould will cause microbial spoilage in a matter of days. So to this end, a product like cheese must be vacuum-packed, right, to protect the product against mould infestation, but also to protect against moisture loss and so forth.
We also have the benefit of using mixed atmosphere such as nitrogen and carbon dioxide, called modified atmospheric packaging, and this can be used as well as the package to help prolong shelf life, and to help retain moisture and the integrity of the product.
And then there's oxygen. Some products are sensitive to oxygen. In case of butter and nuts, oxidative rancidity may develop in the product during storage. Light may also affect these products and so opaque packs, possibly a foil laminate is needed to give good protection. It should be remembered that aluminum foil at a thickness greater than 70 microns is a complete barrier to all gases. So it prevents aromas and flavors traveling from one product to another and so forth.
When packaging vegetables, for instance, they're living materials, right? They consume oxygen, release carbon dioxide after being harvested and packed. If the package is unsuitable, the oxygen is used, the vegetables may deteriorate, may just look off, right? So again we can use packaging to help prolong shelf life and help prolong the integrity of the product and so forth.
Linda: What about recycling? You mentioned a little bit about recycling but I suppose everybody's concerned nowadays about that, and which types of packaging can be recycled and are there some that can't be recycled and are single use only?
Ed: Glass and aluminum are 100% recyclable. As are many plastics. In fact aluminum uses 95% less energy than aluminum made from, sorry - recycled aluminum uses 95% less energy than aluminum made from virgin stock. In terms of paper, paper is an excellent product in terms of recycling. It can only be recycled a number of times because the actual fibre length in the paper strands gets shorter and shorter every time you recycle it. So usually a maximum of five to six times it can be recycled. However, after that it can go for incineration to energy recovery. And paper includes newspapers, magazines, sugar bags, calendars, diaries, computer paper, egg boxes, holiday brochures, school books, there's an absolute huge range, okay? And again all of these are recyclable.
In terms of metal there's aluminium cans, drink cans, empty deodorant cans, but again you have to check with your individual recycler if these are allowable and so forth. There's also steel cans from your beans and your pet foods and so forth, biscuit tins, soup tins, there's a whole range.
In terms of plastics, the plastics must be rigid, as in solid plastics. These would include mineral bottles, water bottles, mouthwash, salad dressing, cosmetics, soap bottles, all of these are recyclable. Shampoos are recyclable, household cleaning bottles, again recyclable, laundry detergent bottles, rigid plastic trays, it doesn't matter whether they're black or clear or white, they're all recyclable. And I previously mentioned yogurt containers and plastic salad tubs. Again, these are all examples of rigid plastic materials that are 100% recyclable and can be used again and again.
Linda: So you mentioned earlier on that spoilage is a problem if the packaging doesn't do its job or if it's not suitable. Can you tell us a little bit more about what causes the spoilage and how that might affect the food?
Ed: Packaging takes many forms and its role is wide and varied. Protection from light, protection from odours and protection from the environment. If it fails to do its job such as pin-holing on foil, faulty seals on pouches or possibly on lids, then the product inside the pack becomes compromised in many different ways which may result in unsafe food.
Linda: Surely these days we need to be more environmentally aware and we've talked about recycling. But we should really be trying to reduce packaging altogether, you know? People describe too much packaging on foods, and should food businesses not just be trying to reduce the amount of packaging that they have?
Ed: It's a very interesting question because sometimes we fail to understand the role of packaging, which is again one of preservation and containment, right? So we are preserving our food, we're containing it, and we are presenting a safe food to the consumer. And it's important, and the production of safe food for the consumer is absolutely huge.
As a country we have EU targets to meet and in 2017 we met those targets by recycling 66% of our packaging waste, and we recovered 86% of our packaging weight. Which is impressive, we're well ahead of the guidelines given to us.
However we can always improve and it's the hope that we can reach a recycling target by 70% in 2030. The packaging community, themselves, have done quite a lot in recent years. A PET bottle, 500 mil bottle for water 10 years ago weighed 25 grams. It now weighs less than 10 grams. So that's huge reduction. Bread bags use 35% less material than they did a decade ago. Refuse sacks, 52% less material, carrier bags 45% less material.
So these are all important in terms of reduction and these are all coming through from packaging manufacturers and packaging designers. But the consumer needs to look at what they are using. And they can help by communicating their concerns to organisations such as Repak and so forth.
Linda: So Ed, tell us, how does packaging impact on food waste, then?
Ed: There are excellent figures available from the World Health Organization which shows that in developing countries up to 30% of the food produced at farm level is lost through improper processing and mostly packaging. So it lets the whole system down. In developed countries, of which Ireland is one, this loss is reduced to below 5%. In actual fact somewhere between three and 5% of the food produced is lost in developed countries compared to in excess of 30% in developing countries, which is huge.
Linda: So there's a lot being done that people actually might not be aware of, but I suppose you might agree that people need to, you can't rush into reducing packaging. You have to still take account of the role that the packaging plays in preserving the food, and I think that's probably what the food businesses need to remember.
So in summary, then, I know we've covered an awful lot of ground today, but could you give us your, what are your top tips for a food business? You know, a small food business and they're looking at choosing their packaging.
Ed: It's important to remember the packaging mirrors social trends. It provides for the consumer goods in specific quantities and in containers as demanded by the consumer. The product and the package should always be developed in tandem.
Take advice from specialists who know and understand the functionality of packaging and the role in producing safe food. Look at recyclable packaging where possible. Biodegradable packaging is in its infancy, but it's worth consideration.
There are a number of key facts. Food packaging should contain the product. It should run smoothly on filling lines, that's very, very important, to withstand the various stresses and strains in the packaging process. It should be easy to handle throughout distribution, protect from dirt and other contamination, prevent physical damage, okay? Prevent odor and taint pickup by the use of proper barriers, stop infestation by insects and vermin, prevent the ingress of microorganisms to retain that safe food environment. It should be compatible with the foodstuff. So with plastic packaging, for instance, should not allow migration of chemicals to taint the food palate and so forth. It should protect against light, control moisture either loss or gain, offer a barrier to oxygen, and retain the ability to retain specific atmosphere such as nitrogen, carbon dioxide.
It should be cost effective. It should have sales appeal, it should stand out. It should communicate product information to the consumer.
Also very, very important this day and age, it should show evidence of tampering, okay? And that's a very, very important area of packaging as well.
And finally, it should open and close easily. Good packaging can sell a poor product but poor quality or badly designed packaging can destroy any potential market for an excellent product.
Linda: Okay, well on that note we'll end there. I'm Linda Gordon and I'd like to thank my guest, Ed O'Neill, for joining us and sharing his expertise on food packaging and everything we need to think about when deciding what packaging we need to use for our products.
This is the safefood Podcast.
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