Success in drinking yoghurt packaging, from concept to shop shelf

The global market for yoghurt drinks was already worth close to $30 billion five years ago according to one consultant. It continues to expand significantly, thanks mainly to increased consumer awareness of the health benefits of yoghurts in general and the continuing trend to consume on the move (although that trend could be affected by COVID-19 lock-downs – and for sure, yoghurts are best consumed soon after they come out of the fridge). More consumers understand that they need to cut down on foodstuffs with a high sugar content in order to stay fit and well. This trend also favours low-fat or fat-free drinks, including yoghurts.

Another consultant puts short-term growth at close to 5%/yr., so the market today is probably close to $38 billion. Whichever way you look at it, that’s an awful lot of yoghurt containers. Which is why manufacturers of dairy products are building up their capacities to ensure that demand for drinking yoghurts can be catered for well into the future.

Market divisions

Yoghurt drinks are mostly packed in plastics bottles – mainly polypropylene and polystyrene. They take up close to two-thirds of the market, with the rest catered for by cardboard laminate solutions. In both cases these containers are non-transparent, for two principal reasons. Non-transparent containers protect the product from the light, which is important for most dairy products, since light can induce oxidation and spoil the flavour.

In addition, being able to see the contents is not always a good thing, especially when some degree of separation can occur during storage. This is not a defect, but a characteristic common to products that contain aqueous and non-aqueous phases. Hence the “shake before use” advice on the label.

PET, an increasingly attractive option

PET bottles are also an increasingly common sight in the drinking yoghurt section of the store. PET lends itself to integrated bottle production and filling, offering a very clean solution highly suitable for this type of product. Today, it is even possible to have a single production system that integrates production, not only of PET bottles but also the bottle preforms with downstream filling and capping.

PET has mechanical properties that are superior to those of other plastics traditionally used for drinking yoghurt. This means, among other things, that the bottles can be made lighter and less costly. Used PET bottles can be collected, washed, granulated, and converted back into bottles again, in line with the idea of a circular economy. SIPA, which is a specialist in PET container production and filling technologies, has a system called XTREME Renew for doing just that.

XTREME Renew integrates two highly innovative technologies in one system: one, converts washed post-consumer PET into high-purity melt; this melt is then fed directly injection-compression molding unit, which produces preforms at very high speed and with low energy consumption. Ideally, XTREME Renew can directly feed a bottle stretch-blow molding system.

On the bottle production front, SIPA offers three options, depending on customer output requirements. The latest is XTRA, a class-leading rotary system that also features high speed and low energy consumption. This complements two existing systems with differing output levels: the SFL range of linear stretch-blow molding units; and ECS SP single-stage injection-stretch-blow molding systems.

Optimizing production systems

Drinking yoghurt of course is not a single product. As in so many other consumer markets, it has its own segments. For example, some drinks contain probiotic cultures, others not. Each has its own set of processing conditions. Plus, rules on production vary between and regions. Under Italian law, for example, the term “yoghurt” can only refer to milk that is fermented with live cultures, provided the density of colony-forming units is equal to or higher than ten million per milliliter of product. Obviously, different types of milk can be used as well as different cultures, providing the consumer with a vast choice in terms of taste and nutrition. SIPA can design lines to cater for all these specific requirements.

The delicacy of dairy

Dairy products are among the most delicate consumer perishables to handle and store, often having shelf lives that are measured in days rather than weeks. Packaging lines most often need to be configured to specific customer requirements that depend on shelf life expectations and the organisation of the downstream distribution chain (for example: can low temperatures be guaranteed all along the chain?).

Various technologies can be incorporated into the packaging line to, for example, thermally treat the product, and to guarantee sterility of the container and the cap. This all depends on the type of product and the distribution needs. Depending on their design, the material they are made from, and how they are produced and handled, container can vary notably in how good they are at preserving the cleanliness, visual appearance, taste, and smell of the product.

Experience and expertise in complete lines

SIPA has decades of experience in supplying complete bottling lines for putting fresh milk and dairy products into PET bottles with shelf lives of as long as three weeks. These lines feature solutions that will guarantee extremely high standards of hygiene, both in terms of control of the filling environment and decontamination of preforms and caps.

Combining its expertise in bottle production with filling technology, SIPA can supply a wide range of what it calls “Sincro Blocs.” These are very compact solutions that integrate blowing, filling and capping in a single unit. The advantages they provide in terms of hygiene, perfectly match the different shelf-life requirements of dairy products, not to mention the return on costof an highly compact system.

All the areas through which bottles and caps transit – filling area included – are located within controlled contamination cabins with sterile air. Special systems guarantee maximum cleanliness (Clean In Place, CIP; Sterilisation In Place, SIP). Various options on such things as product heat treatment, use of sterilising agents, and application of protective foils are available.

The SIPA production range also includes conveying and secondary packaging equipment, enabling the company to act as a single source of complete bottling lines that are extremely reliable and effective.

Designing bottles as well as machines

In addition, SIPA has in-house capability to design containers that are both highly functional and aesthetically pleasing. This means that it can provide a true turnkey solution, from an idea on the back of an envelope all the way through to a possible award-winning drinking yoghurt bottle for the refrigerator.