Blog post

Thursday, May 12th

Published on
May 3, 2016

After three long days full of interesting presentations, discussions, networking and quite some time on the bus day 4 starts with some tired and many happy faces at the breakfast buffet in the modern and spacious hostel of Stuttgart. Bus departure was scheduled for 7:15, so only very few of us were fortunate enough to taste the waffles which the hostel kitchen starts serving from 7:00; I hear from Angelica they were quite good. A small but inexplicable delay of 15 minutes had to be accepted before we finally left towards Freising on the outskirts of Munich some 250 km away.

At 11:15 Adri, our trusted driver actually drives into the parking lot of the Technical University of Munich in Freising. Yes, it was not easy finding the right spot for everybody to disembark but then again it is quite a large bus. As Adri is maneuvering in the narrow parking area Martha suddenly hops on the bus, she will join our illustrious group for the next two days. Glad you could join us Martha!

So here we are at the Technical University of Munich group for nutrition and food process engineering, part of ZIEL which stands for the quite lovely sounding Zentralinstitut für Ernährungs- und Lebensmitteltechnik which I roughly translate into central institute for nutrition and food process engineering. The group of nutrition and food process engineering is chaired by Prof. Dr. Kulozik who received us in person in the pilot hall of the group. In the conference room one story above he treated us to coffee, cold water and cookies, all much appreciated after almost 4 hours of bus ride. The delayed arrival was not unexpected by our hosts who planned the schedule for the day accordingly as they knew we were coming directly from Stuttgart. After the last three days, which were thoroughly organized and structured, the schedule for this day as planned in the booklet was kind of vague for the very first time and left us wondering, what we were going to do. This is due to the ideas of our hosts of the day at the TUM who scheduled an extensive tour through their pilot plans and time for discussions. What made the discussions even nicer was the fact that researchers of the TUM actually asked for individuals of our group, based on their research areas, to visit them in their respective departments but more on that later in this journey blog.

First Prof. Dr. Kulozik gave a talk on the history and current structure of the TUM and with special detail on the technology and dairy sciences at Freising-Weihenstephan where the campus is located for a little over 150 years now. Apparently the first courses or teaching on brewing were given in 1865 in the very same spot, not surprising that it was about brewing beers as the local brewery advertises being the oldest continuously running brewery in the world. A little over 90 years ago the science of dairy products was started as well in the same campus and one of the latest developments was the chair of food and bioprocess engineering, which was founded 2016. In broad strokes the idea of the group is to understand, optimize and make use of processing induced molecular and microstructural changes in complex food systems, which correlates well with part of our (WUR FPE) ideas of our work as well as we also aim to combine molecular aspects with processing techniques. Among the most prominent and for me memorable examples Prof. Kulozik gives about contributions of the TUM towards applied food processing is the continuous production of butter which was involved in the 1930s and ‘40s by Fritz and Eisenreich and is nowadays worldwide the industrial standard.

Directly after the introductory presentation we hung up our presentation posters in the conference room and went straight to a typical Bavarian lunch as prepared by our hosts. For this delicious lunch not only Brezn (Pretzels) and salads were prepared but also a draft machine for beer. Prof. Dr. Kulozik invited us to have a beer for lunch and if my observation was correct it was Dimitris who broke the ice and first got himself a beer. Directly after lunch we were treated to a tour through the pilot plant and research areas of the group. Since our large group was divided into two only one had the pleasure to be lead through the laboratories by Prof. Dr. Kulozik himself. He led us into the different work areas and the PhD students working on the equipment gave us some insight into their work, shared some of their results and tribulations with us. First was Janika Dombrowski who works on the structural formation and analysis of foam. Her work is based on the correlation of foaming properties with the properties found at the foam/liquid interface with applications such as foam drying in mind. Oliver Gmach showed us his work on oil-water emulsions next where he simulated sped-up aging processes by centrifuging samples and monitoring phase separation during centrifugation. Sabine Ambros showed us next her set up for drying of starter cultures and sensitive biomolecules. She investigates the high survival rate of starter culture in vacuum microwave dried foam compared to conventional spray drying techniques but also the creation of edible foams with a green label are in the scope of her interesting work. Next Nicole Haller showed us her approach to separate β-lactoglobuline from whey. Her process consists of three basic steps, the first of which is a selective thermal denaturation which leaves most of the whey protein in its native state while over 70% of β-lactoglobuline is denatured. This denatured protein agglomerates and is separated as solid phase from the rest in a decanter centrifuge. In the third step she selectively adsorbs the residual β-lactoglobuline of the supernatant with membrane adsorption anion exchange chromatography (MAC AIEX). Yuhong Mao works on a similar approach but instead of MAC she investigates the digestion of β-lactoglobuline with immobilized trypsin on a monolithic column as the final step to produce β-lactoglobuline free whey. Next we went to a completely different area of the processing plant with Elisabeth Eschelbek showing us her equipment to produce biological indicators for sterilization processes of packaging surfaces. She produces starter cultures and is able to change their respective surface hydrophibicity via the pH of the fermentation medium. Then she takes samples from the culture and investigates their denaturation under H2O2 sterilization on plastic surfaces. Joseph Dumpler and Melanie Marx showed us their approach towards a more sustainable creation of exportable milk compared to current standard. While milk is being spray dried into powder to export milk powder their approach is to heat preserve milk concentrate, producing product with a similar density and improved properties while saving a lot of processing energy from replacing spray drying as a process step. Our tour was finished with Michael Reitmeyer showing us his approach to membrane filtration using different techniques such as a rotating membrane disk in order to prevent fouling while also looking at the flux- and pressure distribution due to cake layer formation.

After this extensive lab tour we were treated to join fellow scientists who were interested in our work. In my specific case it meant that Angelica, Ali, Victor Qi, Pina, Martijn and I were picked up by Simon to join his group for discussion and a tour of their labs. Simon is a PhD student of the group of Biothermodynamics at TMU, lead by Prof. Dr. Marjana Mincewa who greeted us together with her other PhD students Martin, Franziska and Reina. The relatively young group (about to celebrate it’s 2nd anniversary) is currently working on liquid-liquid chromatographic processes. After each of us from WUR introduced him/herself our hosts introduced themselves and explained what they were working on. During this time we basically blocked off the coffee kitchen, for which I felt sorry when I saw scientists with coffee hungry eyes being turned away from the crowd in front of “their” coffee machine. After a pleasant discussion about everybody’s subjects and trials and tribulations of being a PhD or group leader in Germany and the Netherlands, Prof. Dr. Mincewa and her staff showed us their labs and equipment. For me personally, one of the highlights of this great and informative day, was to have the pleasure of having the concept and ideas behind liquid liquid chromatography explained by Prof. Dr. Mincewa herself, explaining on the equipment, using helping diagrams and answering extensive questioning by myself and Martijn. It was one of these moments were common research interests overlapped and ideas were exchanged between like-minded people that made this situation so very memorable for me. A very very big thank you at this point to the group of Biothermodynamics of TMU from myself.

We finally all met on the bus at 17:00, all of us exhausted (I guess) and most of us very happy (I hope) and went to the luxurious Gasthof Lerner. Luxurious is a word justified after sleeping in youth hostels, if you are reading this and accustomed to sleeping in hotels, you may have to make up your own mind about this place, but is very nice. We were indeed all very happy  After a short break to check into our rooms and maybe even brush our teeth we went straight back to the pilot plant of Food Process Engineering for dinner. Wow. Remember the draft beer I mentioned earlier? Everybody now took advantage of that. A very tasty and special wheat IPA brewed by the brewing technology group of TMU was made available to us and after years of drinking Belgian and Dutch beers and ales and IPA’s and whatnot, I still am amazed by this beer, it was really good. Even better to hear that this beer was not commercially available. A good reason to always be friendly to the guys from brewing technology, as was fittingly remarked this evening. But the dinner was not less memorable in any way. Salads, pretzels (so much better than anything you get anywhere outside of Bavaria, trust me) and meat from the BBQ outside, eaten in the atmosphere of a pilot plant, prepared by fellow PhD students and enjoyed with interesting discussions on all kinds of topics rounded off the evening for me. While some of us (a number satisfyingly close to 100%) went to the local Maibaum Fest, I opted to return to the hotel to finish this report of the fourth day of the 2016 PhD trip to Southern Germany and Switzerland. So far it has been an amazing trip with interesting and interested people everywhere we went and I am excited to see the coming days and continue on this fascinating journey. To the whole group of Food Process Engineering and Prof. Dr. Kulozik but also to everybody else who welcomed us to Freising today a very big Dankeschön from us. As our chair professor Remko Boom said, you are most welcome to visit us in Wageningen and we look forward to seeking out areas where we can collaborate and work together towards common goals.

Auf Wiedersehen.