New scientific article in a journal Agriculture

We are proud to announce our eighth scientific article within this project, published in open access journal Agriculture. This article presents the results of silage process of grape pomace which was carried out during the 90 days. Fresh grape pomace was subdivided in 3 different experiments: grape pomace as a control, grape pomace treated with inoculum of lactic acid bacteria and grape pomace treated with zeolite. During the 90 days the chemical and fermentative characteristics and biologically active compounds were monitored. The obtained results suggest that inoculant and zeolite supplementation can improve the quality of grape pomace silage for later use in ruminant feed. 

The final conference of the project „Sustainable waste management of winery-byproduct“

On December 19 th at the Faculty of food technology and biotechnology was held the final conference of the project „Sustainable waste management of winery-byproduct“. During the conference, the project manager has presented the aim of this project which is the development of technologies for the sustainable waste management of winery-byproduct. Also, during the conference the members of the project team have presented their results obtained by investigation of the extraction process of polyphenols from grape pomace using the green solvents, investigation of technologies for the extraction of oil from grape seeds, the development of the food product based on grape pomace and the composting process of the grape pomace. Furthermore, two invited presentations were held: „The function of bioeconomy for achievement of sustainable development“ which was held by Marina Tišma, PhD from Faculty of food technology in Osijek and the other presentation was held by Nenad Buljan from the company Modus Melior d.o.o. under the title „Interaction of science and business with a successfull comercialization of research results“. 

International Conference – 3rd Black Sea Association of Food Science and Technology – B-FoST 2023

B-FoST 2023 (3rd Black Sea Association of Food Science and Technology) is an international conference that gathers scientists and experts from the fields of Food Technology, Biotechnology and Bioengineering with a focus on the application of new technologies in food engineering. The conference was held in Belgrade. It was originally scheduled to take place from 12 to 15 December 2023, which was changed to 13 and 14 December 2023 shortly before the start of the conference. The conference was organized by: Institute of Food Technology, University of Belgrade, The Serbian Association of Food Technologists (SAFT), European Hygienic Engineering and Design Group (EHEDG), Global Harmonization Initiative (GHI), European Federation of Food Science and Technology (EFFoST), ISEKI Food Association (IFA) and FoodHub Center of Excellence. During the conference, lectures were held on the possibilities of utilizing by-products from the food industry through the application of new technologies and improving existing technologies with the aim of making better use of raw materials and energy sources. The conference was attended by: Assoc. Ph.D. Marina Tomašević and Associate Professor Ph.D. Filip Dujmić with a poster presentation in which they presented the results of research conducted within this project. The poster presentation was entitled: 

1. Katarina Perić K., Dujmić F., Ćurko N., Tomašević M.,* Radojčić Redovniković I., Brnčić M., Kovačević Ganić K.: Effect of ultrasound and cold pressing on the composition of Graševina grape seed oil lipophilic and hydrophilic antioxidants, poster presentation 

OENO Macrowine 2023 congress

OENO Macrowine 2023 is an international congress that joint two international congresses, the 12^th  International Symposium of Oenology of Bordeaux and the 9^th edition of the Macrowine symposium. The congress was held in Bordeaux (France) from 10^th to 13^th July 2023, in the context of a joint organization with the following topics: Plant and Environment - Grape and wine quality, Grape and wine microorganisms: diversity and adaptation, Oenological practices and processes, Wine chemistry, wine components with physiological effects and Sensory properties, psychophysics, experimental economy, connexions with neuroscience. Special emphasis was placed on scientific research related to macromolecules and secondary metabolites of grapes and wine. In addition, the influence of climate change on the composition and overall quality of wine was also discussed, primarily the influence of various viticultural and oenological procedures, including adaptations and opportunities provided by these procedures, as well as their chemical and sensory aspects. Associate professor Natka Ćurko participated on OENO Macrowine 2023 congress and presented the part of the results of the research project with a poster presentation titled:

Ćurko, N., Lukić, K., Jurinjak Tušek, A., Balbino, S., Vukušić Pavičić, T., Tomašević, M., Radojčić Redovniković, I., Kovačević Ganić, K.: Valorization of grape wine pomace using pulsed electric fields (PEF) and supercritical CO₂ (SC CO₂) extraction, Poster.

New scientific article in a journal Separations

We are proud to announce our seventh scientific article within this project published in open access journal Separations. In this work, the solid-liquid extraction of bioactive molecules from grape skin was performed using water as the extraction solvent. The effects of extraction time (t = 60, 75 and 90 min), extraction temperature (T = 40, 60 and 80 °C), solid–liquid phase ratio (S/L = 10, 20 and 30 g/L) and mixing speed (rpm = 250, 500 and 750 1/min) on the total dissolved solids, extraction yield, concentration of total polyphenols, and antioxidant activity were determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. According to response surface modeling, the optimal extraction conditions were obtained (t = 75 min; T = 80 °C; S/L = 30 g/L and rpm = 750 1/min) and the polyphenol concentration was 8.38 mg_GAE/g_d.m.. Moreover, the potential of near-infrared (NIR) spectroscopy coupled with artificial neural network (ANN) modeling for prediction of the physical and chemical properties of prepared extracts was also analyzed.

Participation on Doctoral study day in biotechnical sciences

The doctoral study day in biotechnical sciences invites doctoral students, professors, mentors and all interested in biotechnical sciences, and the main organisers of this event are Faculty of forestry and wood technology, Faculty of agriculture and Faculty of food technology and biotechnology. This year the doctoral study days were held 14^th and 15^thof September 2023 at Faculty of forestry and wood technology and the aim of this meeting is the presentation of doctoral students results. Tea Sokač Cvetnić, mag.ing., the associate on a project, held an oral presentation under the title „Grape skin composting – environmentally friendly treatment of biodegradable waste”about her research results of the project.

Rector’s award

On 29^th of June 2023 in Zagreb was held the rector’s award for the best student’s work. Korina Krog, student of the second year of undergraduate programme at Faculty of food technology and biotechnology, got the rector’s award for the work under the title “Application of Near-infrared spectroscopy in analysis of the composting process of grape skins” under mentorship of associate professor Ana Jurinjak Tušek. Also, her work was chosen among the seven best and she held the presentation about objectives and results. 

Participation at the 3rd International Meeting on Deep Eutectic Systems

The 3rd International Meeting on Deep Eutectic Systems (IMDES 2023) gathers experts from around the world to discuss the newest developments and discoveries in the field of deep eutectic systems. The conference took place in Lisbon, Portugal from 19^th to 22^nd June 2023 organized by the FCT/NOVA University of Lisbon and DES Solution group. The conference covered topics all the way from fundamentals of the deep eutectic system to their application in biotechnology, extraction techniques, and  pharma industry. Ivana Radojčić Redovniković, Ph.D., Kristina Radošević, Ph.D., Manuela Panić, Ph.D. and Anja Damjanović, MSc, presented their research results of the project during lectures and poster presentations.

Participation at 58th Croatian and 18th International Symposium on Agriculture (SA 2023)

58^th Croatian and 18^th International Symposium on Agriculture is an international symposium where scientists can present their results, share ideas in the field of agriculture. The symposium was held in Dubrovnik, from 11th to 17th February 2023 and the main organisators were University of Zagreb Faculty of Agriculture and Josip Juraj Strossmayer University Faculty of Agrobiotechnical Sciences Osijek. During the symposium, a lectures from different sections were held such as agroecology and environemntal protection, plant production and protection, animal sciences etc. Assoc. Prof. Maja Benković, Assoc. Prof. Davor Valinger, Assoc. Prof. Ana Jurinjak Tušek, Assist. Prof. Tamara Jurina and Tea Sokač Cvetnić, mag.ing.oecoing. presented their results of the project under the titles: „The use of grape pomace in food products“ (oral presentation), „In-vessel composting of grape pomace“ and „Applicability of near-infrared spectroscopy in the analysis of macronutrient contents of grape pomace and grape pomace mixtures“ (poster presentation).

Participation at GENP 2022 Conference

GENP 2022 (Green Extraction of Natural Products) is an international conference focused on agro-food waste valorization, bioprocess resources and innovative technology solutions that can be implemented in various fields such as food and pharma industry, cosmetics, biofuel production and green chemistry. The main goal of this conference was to facilitate the interaction between experts from industry and leading academic scientists in these fields to exchange and share their experiences and research results on all aspects of green extraction, discuss the most recent innovations, and trends and generate new ideas. The conference took place in Valamar Diamant hotel Poreč from 27^th to 28^th of October 2022. The main organizer of the conference was the Faculty of Food Technology and Biotechnology from the University of Zagreb with co-organisers ISEKI - Food Association, EFFoST, MDPI and Elsevier. The main topics of the lectures were focused on alternative solvents for green extractions, innovative approaches during extraction process design, valorization of by-products and biorefinery. Karin Kovačević Ganić, PhD, Natka Ćurko, PhD, Marina Tomašević, PhD, Marina Cvjetko Bubalo, PhD, Ivana Radojčić Redovniković, PhD, Manuela Panić, PhD and Anja Damjanović, mag. ing. presented their research results of the project during lectures and poster presentation. 

Participation at 4-GREEN 2022 conference

4-GREEN 2022 (Natural resources, green technology and sustainable development) is an international conference focused on green technologies which can be used in a different fields of production. This is a conference where experts present recent achievements, share the latest developments and address the challenges in these challenging topics. The conference was held in hotel International in Zagreb from 14^th to 16^th September 2022. The main organizers of the conference are Croatian forest research institute, Faculty of food technology and biotechnology from the University of Zagreb, Faculty of forestry from the University of Zagreb, Institute for Adriatic crops and karst reclamation, Croatian society of biotechnology, Academy of forestry sciences and Croatian chamber of forestry and wood technology engineers. During the conference were held presentations from different fields such as environment and climate change, plant extracts – value added products, green technologies and other. Karin Kovačević Ganić, PhD, Natka Ćurko, PhD, Marina Tomašević, PhD, Marina Cvjetko Bubalo, PhD, Ivana Radojčić Redovniković, PhD, Manuela Panić, PhD, Anita Pušek, mag. ing., Anja Damjanović, mag. ing. and Tea Sokač, mag. ing. presented their research results of the project during lectures and poster presentations.

The instruments necessary for the performance of the experiments are delivered

In July of 2022 were delivered the instruments which are necessary for the performance of the experiments under the project. 

1. Line for milling and separation by fractions – portable equipment

The system for milling and separating particles enables automatic grinding of raw materials and separation of materials of the desired particle size. The shape, size and size distribution of material particles are important factors that directly affect the extraction process of certain components and have an impact on the chemical and physical properties of the finished products.

The device will be able to:

• milling of material and automatic separation into fractions of a certain size

• development and determination of the optimal particle size for the extraction of the desired components

• the possibility of switching process parameters from laboratory frameworks to semi-industrial/industrial frameworks

2. Device for milling at a reduced temperature

Material milling technology at low temperatures avoids the disadvantages of dry and wet grinding, especially a significant increase in the temperature of the material and its sticking and enables continuous monitoring and individual temperature adjustment. Milling at low temperatures directly affects the limited generation of heat during the process, which enables the preservation of the activity of bioactive components. The device is connected using pipes to the source of cooling liquid, which is stored in the tank, thus providing an integrated cooling system. The device offers the option of setting the grinding cycle (grinding time, number of revolutions per minute, breaks) at a fixed temperature.

The device will be able to:

• milling of components from grape pomace under controlled conditions

• development and determination of optimal milling conditions for a specific product and extraction of desired components

• the possibility of switching process parameters from laboratory frameworks to semi-industrial/industrial frameworks

3. Vacuum oven

A vacuum dryer is often used for the drying of thermo-sensitive materials which are easily degradable and oxidize quickly. Vacuum drying is an operation in which moist material is dried under sub-atmospheric pressures. The lower pressure allows drying temperature to be reduced and higher quality to be obtained (it includes the preservation of nutrition components and sensory characteristics of food material). During the vacuum drying also the oxygen content is reduced which ensures the oxidation stability of the dried material.

4. NIR (Near Infrared Spectrometer)

Near-infrared spectroscopy is a spectroscopy method that uses the near-infrared area of the electromagnetic spectrum in the ranges from 750 – 2500 nm for material characterization. The use of this instrument provides some benefits such as easy to use, fast analysis, simultaneous results for multiple parameters and reliable results. The application of this method is in the pharmaceutical, chemical and food industries, also in medicine. The newer version of NIR spectrometer provides higher sensitivity, lower mass and size. 

Review article published in open access journal Processes

We are proud to announce our third review article within this project published in open access journal Processes. In this article is presented the possibility of mathematical modeling and optimization for the composting process which is an environmentally friendly process for degradation of organic waste and turning it in a compost, natural fertilizer. A few parameters are important for this process such as temperature, C/N ratio, particle size and moisture content. The efficiency of the composting process depends on all mentioned parameters and their interactions which can be achieved by mathematical modeling and optimization. In the last 20 years, the interest for optimization of the composting process is increasing. In this work, the advantages and limitations of the optimization and mathematical modeling for improving composting processes are shown. 

Participation at the XIV Meeting of Young Chemical Engineers

Project assistants Anita Pušek, mag. ing. and Tea Sokač, mag. ing. have participated on XIV. Meeting of Chemical Engineers from 24^th to 25^th February 2022. at Faculty of Chemical Engineering and Technology in Zagreb. This is an International Conference where scientists, technologist and students can present their results, share ideas and meet colleagues who work in the same field. During the Meeting were held presentations from different fields such as reaction engineering, environmental engineering and other. Assistants Anita and Tea have participated with poster presentation and presented their results under the titles: “Modelling of drying process of grape pomace” and “Characterization of grape pomace and monitoring of its changes during the silage”.

Participation in the workshop “COST 1st Greenering entrepreneurship course”

A one-week long online Entrepreneurship course took place from 15 th to 22 nd of October 2021 and helped young researchers to transform their technologies into products or services. The program was organized by COST action Greenering CA18224, which gathers over 170 participants from 35 countries. The aim of this course was to become acquainted with the process of innovation development, idea and business plan generation techniques, cash flow forecasts and economic evaluation and finally, pitching ideas to potential investors. This hands-on training course combined with lectures helped us understand technology transfer into the market. Besides that, this international program provided networking between participants and organizers, idea generation and hopefully a start to future collaborations.

Published scientific paper in the journal Foods

We are proud to announce our second scientific article within this project published in open access journal Foods. In this work are presented the results for different drying methods and their effect on the stability of biologically active compounds. The drying process of grape pomace is one of the methods to retain the initial characteristics of pomace in order to reuse the pomace for other products. It was investigated three drying methods: vacuum drying at 35, 50 and 70 ⁰ C; drying in a conventional dryer and open sun drying. After the drying processes, the extracts were prepared and used for determination of polyphenols, tannins and tartaric acid content. The drying kinetic was described by Peleg's model. From the obtained results, as the optimal method for grape pomace drying was chosen drying in a vacuum dryer at 70 ⁰ C because it takes less time and there is no degradation of biologically active compounds. The published results could help in an industry where are produced a huge amounts of wine waste for the purpose of preparing and storing pomace to be further exploited.

Scientific paper published in Molecules

Panić, M., Gunjević, V., Radošević, K., Cvjetko Bubalo, M., Kovačević Ganić, K., Ivana Radojčić Redovniković, I., COSMOtherm as an Effective Tool for Selection of Deep Eutectic Solvents Based Ready-To-Use Extracts from Graševina Grape Pomace. Molecules 2021, 26, 4722.  https://doi.org/10.3390/molecules26164722

We are proud to announce our first scientific article within this project published in open access journal Molecules. Herein we presented our data on preparation of Graševina grape pomace ready-to-use extracts rich in polyphenols. The extraction was performed in natural deep eutectic solvents and the optimal solvent was selected using COSMOtherm software, significantly reducing the time for prelyminary experiments. The prepared extracts were toroughly analysed for specific polyphenolic compounds and their antioxidant activity was evaluated. Subsequently, the extracts were tested on human keranocyte (HaCaT) cell line where the extracts exerted a stimulating effect on cells growth. The published data could help the winery industry to achieve zero waste creation while generating an added value in a form of ready-to-use polyphenols rich product that can later be used in cosmetic and pharmaceutical industry.

Participation in Big Bang camp

Postdoctoral researcher Manuela Panić, PhD and project assistant Veronika Gunjević, PhD, have participated in Big Bang camp from 15^th to 19^th September 2021. in Rijeka. Big Bang camp is a 5-day mentoring program that helps scientists and entrepreneurs to transform technology into marketable product or service. It was organized by StepRi science and technology park of the University of Rijeka and the US Embassy Zagreb. During the program we learned about market research, business plan creation, finances calculation and how to prepare a successful pitch presentation. Upon gaining the knowledge, on the last day we presented our project in a pitch presentation in front of the investors. During the program, we networked with other participants and arranged future collaborations.

Meeting with project partner– KUTJEVO Plc.

As a part of the project “Sustainable waste management of winery by-product”, KK.01.1.1.07.0007, dissemination activity, there was a meeting held in Kutjevo on 02.09.2021 starting at 10 am. Ivana Radojčić Redovniković, project manager, Karin Kovačević Ganić, project team member from Faculty of Food Technology and Biotechnology, University of Zagreb, Darko Uher, project associate from Faculty of Agriculture, Tamara Jakovljević, project associate from Croatian Forest Research Institute, Grozdana Mitrić, Quality and food safety manager, and Zlatko Romić, Cotrolling manager from KUTJEVO d.d. participated the meeting.

During the meeting Ivana Radojčić Redovniković presented current state of the project including short-term and long-term plans that are needed for succesfull implementation of project activities. The partner presented technology of grape proccesing with a special emphasis on grape collection. Furtheremore, the term for taking a sample of grape pomace was defined.

Participation on an international congress

In June 2021 Prof. Ivana Radojčić Redovniković, Asst. prof. Marina Cvjetko Bubalo and postdoctoral researcher Manuela Panić, PhD have participated on an international virtual conference “2nd International Meeting on Deep Eutectic Systems” held in Lisboa, Portugal. Prof. Ivana Radojčić Redovniković gave a talk titled “Sustainable waste management from wine production“. She presented results of the study regarding grape pomace polyphenols extraction in natural deep eutectic solvents with the use of COSMO-RS software.

“Kick off” meeting held on 09/02/2021

On February 9, 2020, the Kick-off meeting of the project team was held at the Faculty of Food Technology and Biotechnology. The meeting was chaired by Ivana Radojčić Redovniković, project leader. The researchers of the project were present at the meeting. The purpose of the meeting was to introduce the project to those present and to clarify the purpose and goal of the project. In addition, the team members discussed the objectives of the project, the expected results and referred to the activities that will be carried out in the next three years. Furthermore, Ms. Grozdana Mitrić, a member of the project team from the partners of the institution Kutjevo Plc., briefly presented the work of the company and the potential contribution of the project to the sustainable management of a large amount of waste generated during their wine production. The final statement was given by the project leader, who mentioned activities on the project that need to be carried out in the coming period and announced the creation of the project website.