Rigorous separation of juice and fruit chunks
The crucial factor for gentle processing and structure retention of the fruit chunks is rigorous separation of the juice from the fruit chunks right from the start in the process section. The aseptic juice concentrate is handled separately from the fruit chunks themselves, measuring up to six times six times six millimetres. They are delivered by fruit producers from Greece and Turkey as ten-kilogram IQF (individually quick-frozen) blocks, and mixed with juice in two 5,000-litre tanks in a ratio of 40 to 60 in order to create what is called a “slurry” – without any crushing or maceration. The agitators in the tanks have been specially designed for this purpose. The concept of slow stirring produces a significant reduction in the shear forces operating here. The slurry is then pasteurised in a VarioFlash H shell-and-tube heat exchanger featuring interior cross-corrugated tubes, which increase the turbulent flow for an improved heat transfer with the medium-to-high-viscosity products. Following a heat-holding time of 21 to 30 seconds, the slurry is passed directly to the pre-dosing filler in the bottling hall. The product is delivered by ultra-gentle, frequency-controlled twin-screw pumps.
Simultaneous juice treatment in the syrup kitchen begins with a continuously operating sugar dissolving station, which accepts the sugar from 1,000-kilogram big bags and dissolves it at temperatures of 40 degrees Celsius at a rate of up to 15,000 litres an hour (simple syrup) to create sugar syrup of 65 degrees Brix, which is then cooled down. At the same time, pectin and other constituents such as citric acid are quickly dissolved using a special technology. The juice concentrate is removed from its aseptic packaging by two twin-screw pumps. The constituents are mixed with pretreated product water in two 40,000-litre tanks to create the finished beverage. The beverage is examined in the laboratory, and has to be approved by Quality Control before thermal product treatment and bottling. For highly viscous products like mango or guava, a homogeniser is also provided. The juice is pasteurised in a dedicated VarioFlash H heat exchanger, and is also passed through a product deaerator, so as to remove all the oxygen content. This deaerator is fitted with an aroma recovery feature for preserving the full taste intensity of the juice.
FlexiFruit filler with a pre-dosing starwheel
The finished juice, still separate from the fruit chunks, is now also passed to the filling line, which is located in the separate bottling hall. Its heart is the PET monobloc, comprising a Contiform H16 hotfill stretch blow-moulding machine, a FlexiFruit filler with a pre-dosing starwheel for the fruit-chunk slurry, the main filler carousel for the juice, plus a capper. The monobloc has been dimensioned for handling 25,000 300-millilitre bottles or later on 18,000 one-litre bottles an hour. The pre-dosing machine, with its 33 valves, fills each 300-millilitre PET container with 30 millilitres of slurry, produced from fruit chunks and juice in a ratio of 40 to 60. It is able to handle large fruit chunks measuring up to ten times ten times ten millimetres.
The main filler possesses 55 valves, each of them fitted with a weighing cell, so as to assure an accurate final fill quantity of 300 millilitres with a deviation of plus/minus 0.5 per cent. And before the bottles reach the juice filler, the weighing cells simultaneously measure the quantity of slurry dosed into each of them as well, and send this value as feedback to the pre-dosing filler, ensuring that the filling accuracy of each individual pre-dosing valve is continuously optimised. Thus each and every bottle is checked, making sure that the desired fill quantity of 300 millilitres is complied with, irrespective of the slurry filling function. The PET containers are fitted with sterilised 38-millimetre wide-neck plastic screw-caps with an O2 scavenger. The hotfill monobloc features integrated automatic CIP (Cleaning in Place) and SIP (Sterilisation in Place) systems.
“Full marks to KRONES.”
“The entire line, including the process section, was installed by the Krones team in a record time of just six weeks, and validated straight away within 15 days”, explains Technical Director Magdy Ismail. “Production started on 12 July 2011, and by 1 August we were on the market. The yield from the raw materials used is very good, the damage rate to the sensitive fruit chunks is minimal, at less than ten per cent, and the bottling line’s performance is highly satisfactory, at over 80 per cent.” His boss, Salam El-Hammamy, sums up the firm’s experience with the new technology as follows: “Working with just a single vendor for the process section and the bottling line is definitely better, and avoids any interfacing problems. Krones’ system has proved to be highly flexible for managing different recipes and individual components. The compactly dimensioned line layout makes optimum use of the space available, minimises the piping routes and operator legwork required, and increases the product yield. The concept also places a lot of emphasis on good manufacturing practice and hygienic design for eliminating microbiological problems. And Krones enabled the operators to get the thorough training they needed at all levels. The entire project went off like clockwork and right on schedule. Full marks to Krones. They did a one-hundred-per-cent excellent job.”