GS

M.Sc. Gabriela Saavedra

  • Postanschrift: Kaiserstr. 12
    Liefer- und Besucheranschrift: Gotthard-Franz-Straße 3
    Geb. 50.31, 4. OG
    D-76131 Karlsruhe

About myself

I was born and raised in Peru. In Lima, I went to the German school, where I obtained the German Baccalaureate. I came to Germany to study bioprocess engineering at KIT. During my second semester, I was given the opportunity to work at the Institute of Food Process Engineering (LVT). Thereafter, my interest in food processing grew. During my Bachelor studies, I worked as an intern at Thomy AG (Basel, Switzerland). My work there gave me more insight into the production of food emulsions such as mayonnaise and salad dressings. I was able to apply the gained knowledge in my bachelor’s thesis, in which I investigated the effects of flow patterns on the oil droplets during the spray drying of emulsions. Even though the topic of emulsions is interesting, I wanted to learn more about other processes used in food industry. Therefore, I worked as an intern at Olam Cocoa (Koog aan de Zaan, The Netherlands) for six months during my Master studies investigating the chemical and physical processes occurring during the roasting of cocoa beans. Since August 2017, I have been working in my doctoral studies at LVT.

Main focus of research

Biopolymers, such as pectins, are used in food production to create textures and gels (e.g. in jams and marmalades). However, the gelling properties of pectins can also be used to synthesise microgel particles. Microgel particles are colloids, each consisting of a gelled polymer network. As such, microgel particles combine the properties of particles, gel networks and the polymer chains used for the microgel formation. For this reason, microgel particles are of great interest for the food industry. They can be used as texturisers and emulsifiers in various applications. The focus of my research is the synthesis of pectin-based microgel particles and their characterisation with the aim to develop preparation processes suitable for controlling particle structure and properties.

Methods

Microgel formation is composed of a mixing step and of a droplet/gel breakup step which correspond to the processes occurring during the emulsification of fluids. For this reason, the machines used for emulsification (high-pressure homogenization, rotor-stator system, etc.) can also be employed for the microgel formation. Optical and rheological methods are used for the characterization of microgel particles. Further characterization methods are employed depending on the application of the particles. For example, the interfacial properties of the microgels are relevant for their use as emulsifiers. These are measured using tensiometry and dilational rheology.

Aktuelle Angebote für Bachelor- und Masterarbeiten
Titel Datum Typ Betreuer

Publications


2021
Emulsions stabilised with pectin-based microgels: investigations into the effect of pH and ionic strength on emulsion stability
Saavedra Isusi, G. I.; Weilandt, M.; Majollari, I.; Karbstein, H. P.; Schaaf, U. S. van der
2021. Food & function. doi:10.1039/D1FO00891A
Emulsions stabilised with pectin-based microgels: Investigations into the break-up of droplets in the presence of microgels
Saavedra Isusi, G. I.; Lohner, N.; Karbstein, H. P.; Schaaf, U. S. van der
2021. Journal of Food Engineering, 294, Art. Nr.: 110421. doi:10.1016/j.jfoodeng.2020.110421
2020
Polymer or microgel particle: Differences in emulsifying properties of pectin as microgel or as individual polymer chains
Saavedra Isusi, G. I.; Bindereif, B.; Karbstein, H. P.; Schaaf, U. S. van der
2020. Colloids and surfaces / A, 598, Art.-Nr.: 124793. doi:10.1016/j.colsurfa.2020.124793
Microstructures and conformational arrangement in emulsions caused by concentration ratios of pectin-based microgels and oil
Saavedra Isusi, G. I.; Madlindl, L. B.; Karbstein, H. P.; Schaaf, U. S. van der
2020. Colloids and surfaces / A, 602, Article: 125166. doi:10.1016/j.colsurfa.2020.125166
2019
Microgel particle formation: Influence of mechanical properties of pectin-based gels on microgel particle size distribution
Saavedra Isusi, G. I.; Karbstein, H. P.; Schaaf, U. S. van der
2019. Food hydrocolloids, 94, 105–113. doi:10.1016/j.foodhyd.2019.02.053

Presentations


2021
Einfluss des Öl-Mikrogel-Konzentrationsverhältnisses auf die Emulgierwirkung von pektinbasierten Mikrogelpartikeln
Saavedra Isusi, G. I.; Madlindl, L.; Karbstein, H. P.; Schaaf, U. S. van der
2021. Jahrestreffen der ProcessNet-Fachgruppen Lebensmittelverfahrenstechnik, Mischvorgänge, Grenzflächenbestimmte Systeme und Prozesse (2021), Online, March 11–12, 2021
2019
Characterization of the mechanical response of pectin-based gels towards dispersing forces used in top down microgel formation processes
Saavedra Isusi, G. I.; Drieß, A.; Karbstein, H. P.; Schaaf, U. S. van der
2019. 20th Gums and Stabilisers for the Food Industry Conference (2019), San Sebastián, Spain, June 11–14, 2019

Posters


2022
Emulsions stabilised with pectin-based microgels: Investigations into the effect of pH and microgel particle concentrations on emulsion stability
Martin, D. I.; Saavedra Isusi, G. I.; Karbstein, H. P.; Schaaf, U. S. van der
2022, June 27. 18th European Student Colloid Conference (ESC 2022), Szeged, Hungary, June 26–30, 2022
Emulsionsstabilisierung mit pektinbasierten Mikrogelen: Einfluss des pH-Wertes und der Ionenstärke auf die Emulsionsstabilität
Martin, D.; Saavedra Isusi, G. I.; Weilandt, M.; Majollari, I.; Karbstein, H. P.; Schaaf, U. S. van der
2022, March 10. Jahrestreffen der ProcessNet-Fachgruppen Lebensmittelverfahrenstechnik und Trocknungstechnik (2022), Frankfurt am Main, Germany, March 10–11, 2022
2019
Influence of mechanical properties of pectin-based gels on obtained particle size distribution during top down microgel formation
Saavedra Isusi, G. I.; Drieß, A.; Karbstein, H. P.; Schaaf, U. S. van der
2019. Jahrestreffen der ProcessNet-Fachgruppen Agglomerations- und Schüttguttechnik und Lebensmittelverfahrenstechnik (2019), Lausanne, Switzerland, March 5–7, 2019
2018
Structural changes in pectin-based microgel particle suspensions caused by polymer structure and ion strength
Saavedra Isusi, G. I.; Karbstein, H. P.; Schaaf, U. S. van der
2018. Jahrestreffen der ProcessNet-Fachgruppe Lebensmittelverfahrenstechnik (2018), Berlin, Germany, March 5–6, 2018