There was a time when drinks and food were noticeably different. Yes, milk has always been a nutritional food enjoyed by many, and the numerous and various innovative flavourings have had the effect of extending its attractions. But in recent years the whole concept of ‘food in a bottle’ has taken on a new dimension.

In the Far East especially, a trend has developed for beverages to have ‘solid’ pieces included, such as fruit, fibres, and cereals, which turn what would otherwise be just a refreshing drink—intended simply to quench the thirst—into a meal in itself. The age of the ‘liquid breakfast’, for example, is upon us.

The benefits are many, with users choosing these ‘drinks’ both for refreshment and as valuable foods that perfectly fit a modern hectic lifestyle. Milk and fruit drinks can be dosed with fruit, coconut, nuts, aloe vera pieces, or even berries and cereals to make exciting foods that are perceived as being of higher quality than liquids alone. Further, with the inclusion of fruit pulps and fibres, these mimic more faithfully freshly squeezed juice.

To date, extensive tests have been run for the filling and dosing of drinks using a range of products such as peaches, chestnuts and even walnut kernels, with different carrier liquids of various viscosities both for the processing and filling parts.

The process of preparation and thermal treatment is a critical phase in terms of sterilisation and handling; the percentage of particles, their dimensions, the density and viscosity of the liquid carrier, all contribute to the final taste of the product and are, therefore, critical parameters in the process.

Aseptic technology is typically used for this process, so as to reduce the microbial load inside the product and the filling and capping environment. This achieves the required final product shelf-life (up to 18 months), and preserves product quality at the lowest capital and operational cost.

However, depending on the ingredients that are included for the ‘drinks’, some applications would actually require two-stream process lines to optimise the quality of the process: one dedicated to the thermal treatment of the pieces and the other to the thermal treatment of the clear liquid. This is so as to optimise the thermal stress on the liquid part but not on the pieces as they are the most valuable part of the beverage—this therefore guarantees maximum quality of the final product.

For beverage manufacturers looking to venture into this product category, just knowing the fact that they would need to invest in two different machines for a single overall product application can be discouraging.

Yet, for concerned parties such as these, they need fret not because advances in technology today have made it possible to aseptically dose fruit or cereal pieces into beverages with a single integrated machine. Using an aseptic dual filling system, beverage manufacturers can therefore meet the current consumer demands for innovative beverage products that are more than just meant for quenching thirst.

An aseptic dual filling system can be used for two-stream processing and provides an effective way of filling drinks that include solid pieces of up 10x10x10 mm. Such a system would use two different fillers—one for solid particles, and the other for filling still beverages.

The solid-particle filler comprises a mechanical piston/cylinder with a volume setting from 10 to 150 ml, moved by an electronic cylinder.

Following filling of the solid pieces, the bottle is then moved to a standard volumetric, electronic filler—the still beverage filler—where juice or the required beverage will be added, thereby completing the aseptic filling process.

Other than the obvious advantage of having an integrated machine instead of two separate machines, a dual filling system can also provide manufacturers with other benefits:

With the separation of the two thermal treatment processes, it allows for maximal quality of the solid particles to be attained. Prior to the creation of a dual fill system, the technology conventionally used for the bottling of beverages with large solid particles had been hot fill, rather than aseptic. As hot fill technology induces more thermal stress than aseptic technology, product quality could be reduced; a reverse now that aseptic filling is available for this type of beverage.

In addition, with the use of two separate thermal treatment processes, the solid particles can also be gently dosed without any mechanical stress. This therefore allows manufacturers to achieve negligible damage in the solid pieces present in the final beverage, thereby increasing product quality further.

The aseptic integrity of the particle filler can be maintained by the presence of a hygienic seal around the piston which will prevent product leaking through to the non-aseptic side. By prohibiting contact between the filling nozzle and the bottle neck, filling can be made very ‘clean’.

Also, aseptic technology is suitable for high acid (HA) or low acid (LA) products and can achieve the most demanding microbiological validation protocol specifications. All sanitation and sterilisation cycles can be automatically controlled at all critical control points.

Further, the system offers flexibility for manufacturers. When required, the dosing volume can easily be regulated from 30 ml to 150 ml by changing the dosing value on the Human Machine Interface (HMI) system.

The system can maintain a production level of 800 bottles per minute (bpm) or 48,000 bph (bottles per hour) with a filling accuracy of +/- five percent of dosed volume—these match the output and accuracy of a conventional industry standard filler.

Also, systems such as these are capable of a small footprint as lighter PET bottles can be used instead of those that were used with hot fill technology previously. Therefore, not only can manufacturers save on costs for production, but they can also save on requirements for PET material for the bottles, contributing to a greener production process.