Last year, Gropper celebrated its 90th anniversary. The company has grown considerably since its founding: the erstwhile cheese maker is now a mid-sized enterprise producing private-label dairy products, not-from-concentrate (NFC) juices, smoothies, and bottled water for customers across Europe. Gropper now processes around 350 million litres of milk a year. Despite these enormous quantities, regionalism still plays an important role, as Berthold Burgmeier, Head of Engineering, explains: "We source our milk from around 870 farmers within a 70-kilometre radius of the dairy. The only exception is organic milk, which we also source from the foothills of the Alps since there are not enough organic dairy farms in our region to meet our needs." 

Originally an all-dairy operation, Gropper now also produces juice, smoothies, and bottled water. The companys spirit of innovation is strong: "When it comes to product development, we are more like a brand manufacturer than a private-label supplier," says Karl Klein, Managing Director Production and Technology at Gropper. "We dont wait for our customers to come to us. We approach them proactively with new ideas."

As a result, Gropper has been successfully making organic products for supermarket chains since 2006. That same year, the company surprised its customers by suggesting they bring smoothies to the German market—long before many of the major brands. In 2009, Gropper began producing NFC juices in PET containers for grocery discounters. "Our latest coup is our own organic mineral water brand, rieser Urwasser. It has given our dairy a foot in the door to one of Germanys biggest grocery discounters," Klein says with an unmistakable touch of pride.

CLEAR EXPECTATIONS

Krones became familiar with Groppers untiring pursuit of innovation and willingness to take risks back in 2004, when the dairy decided to move into PET packaging. "PET containers make the product visible," explains Klein. "Bottles made of PET plastic are also very lightweight, fully resealable, and hygienically perfect."

The company had very specific ideas about how its first PET line should be equipped. They wanted to use a two-colour filler with dry-aseptic technology. "Its the standard in the dairy industry. All of our cup fillers work on that principle. So it was clear that our PET containers and caps would also have to be sanitised in this way," says Klein. 

Since Krones didnt have that type of filler in its portfolio at the time, the Neutraubling-based company delivered just a Contiform stretch blow-moulder and a two-colour sleeve labeller that was designed especially for Gropper. 

But Krones filling technology experts had taken the customers idea as inspiration and developed a four-color filler that uses gaseous hydrogen peroxide to sterilise the containers and caps. And their efforts paid off. In 2005, when Gropper was considering its next investment in a PET line, the company chose this newly developed filler from Krones. "It was still just a prototype—so of course, there were some ups and downs," recalls Burgmeier. "When we were looking to add yet another line in 2012, we weighed very carefully whether we should go with Krones again. In the end, though, we realised that Krones had continually improved its dry-aseptic process in the meantime—and so we did. Right now, nobody else on the market can build a dry-aseptic PET line at the same level of quality and reliability."

CHAMPIonING DRY ASEPTICS

Today, PET containers account for about 40 percent of Groppers total production volume. The success of PET packaging is also reflected in the dairys capital expenditure. In 2015, the company decided to significantly increase its capacity for producing in PET containers and launched a wave of investment. That same year, Gropper opened a second plant in Stockach, near Lake Constance, which was followed in 2018 by a plant in Moers as part of a joint venture with Dr. Oetker. Two PET lines from Krones are now in operation at each location. In addition, the Bissingen plant also got two new lines, in 2018 and 2019. 

Both lines once again feature a PET-Asept D system from Krones, each with a rated capacity of 18,000 1.0-litre containers per hour. This aseptic filler-capper block processes not only milk, dairy drinks, and whipping cream but also coffee beverages, NFC juices, smoothies, and water. The latest filler generation gives Gropper the utmost flexibility in container choice. On earlier models, changing bottle shape meant replacing handling parts. Today, all container types can be processed with a single set of handling parts. Because the clean room no longer has to be opened, cleaning times are also shorter—and the lines performance has increased by around 25 percent compared with earlier models. 

With the PET-Asept D, Gropper has once again consciously chosen to keep the filler and the blow-moulder separate. One reason is to clearly segregate packaging material storage from the hygienic space around the filler. Preforms and packaging materials are fed into the lines from a central location at the front end of the bottling hall—and for that reason, the Contifeed preform feed system, the Contiform 3 Pro stretch blow-moulders, and the packer are all sited in this part of the hall. The filler stands at the opposite end of the hall. An AirCo air conveyor transfers the moulded PET containers along the 60-meter (nearly 200-foot) stretch between the two areas. 

"The air conveyor also serves as a buffer. Especially when working with higher-viscosity products, we can run slow filling without impacting the thermal process in the blow moulder," explains Burgmeier. Klein chuckles, adding, "At Gropper, were obsessed with buffers because our experience has been that block set-ups often result in efficiency losses. We really notice that when one of our buffer towers goes down and has to be bypassed. Efficiency immediately drops by four or five percent."

CLEAR FAVOURITE FOR LABELLING

As a private-label producer, Gropper makes countless different products and brands. In order to meet its customers demands, the company has to be able to offer all labelling options. Therefore, both of the new lines include a Solomodul, each of which has two docking stations for wrap-around, pre-cut, and lid labelling stations. The set-up can also accommodate integration of two Autocol labelling stations for self-adhesive labels if needed. If Gropper needs to handle special-shaped bottles on the new lines, a Sleevematic can do the labelling. "We change labels at least five or six times a day. We chose a modular labeller to keep time losses to a minimum," says Burgmeier. 

Gropper has trusted Krones labelling technology ever since they installed their first PET line—and for good reason, as Klein explains: "When it comes to labelling, we’ve never gone with anyone but Krones. Their roots are in labelling and I have the greatest trust in them." To date, Gropper has also exclusively chosen Krones Contiform stretch blow-moulders for bottle production.