A new Academy of Finland (AoF) postdoc research project explores an innovative way to utilise wood hemicelluloses

Wood hemicelluloses are currently treated as low-value by-products of the pulp and paper industry and remain outside of the biorefinery process. The development of value-added applications of hemicelluloses for producing new advanced products will boost forestry operations, promote economic growth, and secure employment in rural areas. To support this goal, Thao Minh Ho in the FoMSci group received funding for a 3-year AoF postdoc research project to develop an innovative approach to employ wood hemicelluloses as capsule wall materials to formulate new synbiotic powders. The project entitled “SynCap: Design of spray-dried synbiotic microcapsules for healthy, functional, and sustainable powders” aims to establish wood hemicelluloses as superior wall materials in the production of microcapsules of probiotics, and potentially many other bioactive compounds.

This project will bring the interdisciplinary expertise and knowledge in food materials sciences, food chemistry, food digestion and microbiology from different research groups within the Faculty of Agriculture and Forestry. The project also establishes a new collaboration with the Biomass Science and Technology research group at the University of Copenhagen (Denmark).

Every year, the AoF funds high-quality scientific research in various fields with the aim of contributing to the renewal, diversification and internalisation of Finnish research. The SynCap project is one of 32 successful applications (out of 217, 15%) in biosciences, health and the environment research fields granted in 2022.

New project: VegeSense aims to secure the supply of high-quality vegetable products

Left: M.Sc. Maria Waldén. Right: Dr. Mourad Kharbach.The food chain is in a shift towards more ecological practices. To feed the growing world population in a sustainable manner, it’s crucial to find solutions to reduce food waste and shift our eating habits to remain within the boundaries of environmental resources. To succeed, the movement towards a planetary diet must be appealing, affordable and uncomplicated for consumers. With ready-cut fresh vegetables consumers can conveniently increase their consumption of fresh vegetables, however the shelf-life of this product category is very limited due to rapid quality loss, often because of over-ripening, browning and tissue degradation, which leads to significant amounts of food waste.

Currently, the underlying deterioration mechanisms after processing and packaging are not sufficiently understood. To tackle this waste, our new project VegeSense, led by Assoc. Prof. Kirsi S. Mikkonen and funded by Novo Nordisk Foundation, aims to provide complementary understanding of these deterioration processes by researching the key metabolites and their role in the quality loss of ready-cut fresh vegetables.

M.Sc. Maria Waldén started in the project as a doctoral researcher in January. Her work is co-supervised by Prof. Mari Sandell and Assoc. Prof. Saijaliisa Kangasjärvi and it will focus on how packaging effects the sensorial quality of ready-cut vegetables and what volatile compounds originate from their metabolic reactions, thus defining their shelf-life. Maria feels very excited about the topic and finds it immensely meaningful, as there is a high possibility of finding solutions that could be applied to practice at an industrial scale rather quickly to reduce environmental pressure. The project is highly multidisciplinary combining food technology, analytical chemistry, plant science and data science. This diversity will allow these complex mechanisms to be deciphered through research from a combination of perspectives and scientific backgrounds.

Dr. Mourad Kharbach started in March as a postdoctoral researcher. He will collaborate with Assoc. Prof. Arto Klami from the Department of Computer Science. Mourad has experience working with large data sets collected by advanced real-time (spectral or chromatography) instruments from different matrices and extracting the hidden information by means of statistical, machine & deep learning, or chemometric tools and linking these with the desired outputs. Particularly, he will develop statistical approaches to analyze untargeted and targeted fingerprinting (e.g., hyperspectral imaging, spectroscopic, and chromatographic) profiles moving beyond traditional lab-based experiments. Mourad will lead the development of non-destructive, fast, reliable, and sensitive methods for sustainable solutions of food materials in terms of quality and safety with the goal to optimally join human forces and machines.

Through this project we aim to provide solutions for reducing food waste and limiting climate change via the improved shelf-life of fresh-cut vegetables and their increased consumption. The resulting improvements in packaging technology would be highly applicable to the food industry and could therefore help the food industry to keep costs – both environmental and economical – in control, which we hope would eventually lead to a decrease in prices and increase in vegetable consumption. By making it financially possible for consumers to conveniently increase their use of fresh vegetables in their diets, healthy eating habits and sustainability can be enhanced.

We are eagerly waiting for another two researchers from the areas of plant science and analytical chemistry to join us in June, complementing our team with their expertise. We will hear more about their work soon, stay tuned!

Picture from left to right: M.Sc. Maria Waldén, spectral imaging test setup, Dr. Mourad Kharbach.

Wood hemicelluloses have great potential as wall materials for spray-dried microencapsulation of bilberry juice

The FinPowder research project funded by Finnish Natural Resources Research Foundation aims to develop a new strategy to offer sustainable and healthy food choices to global consumers while also valorizing Finnish wood-based hemicelluloses and wild berries. Further information about the project can be found here.

Since FinPowder commenced in April 2021, we have evaluated the suitability of different types of hemicelluloses and celluloses for spray-dried microencapsulation of bilberry juice. We have also optimized the methods for the preparation of feed solutions including bilberry juice, and selected hemicelluloses and celluloses. Thanks to a parallel research project driven by Doc. Fabio Valoppi, a new laboratory spray-drier (B-290, Buchi Labortechnik GmbHDE, Essen, Germany) has been installed in our laboratory (Figure), which has provided a research instrument upgrade that also supports the FinPowder project. Initial results of spray-dried microencapsulation of bilberry juice indicated that hemicellulose had a high retention capacity for bioactive compounds during spray drying with an encapsulation efficiency of 70–80%, similar to that of conventional wall materials (gum arabic and maltodextrin). We used a scanning electron microscope (SEM) to determine the morphology and physical appearance of microcapsule powders coated by sGGM are shown in the figure.

Along with the spray-drier installation, we have worked with a technical engineer from Buchi to successfully design a customized drying chamber which allows the collection of powders at different distances in the drying chamber while they are being dried. We have also installed and carried out testing with a high speed camera system that allows us to investigate the particle powder formation, live. These analyses enable us the first time in this project to characterize microcapsule wall formation happening during the spray-dried microencapsulation process. The FinPowder project has received a second year of funding from the Finnish Natural Resources Research Foundation to conduct further investigation on microcapsule powder characteristics, optimization of the spray-dried microencapsulation process, and investigation on the formation mechanism of microcapsule wall. More to come!

Figure: A Buchi spray-drier, physical appearance and morphology (SEM image, on the right) of bilberry microcapsule powders prepared from hemicelluloses.

The in vivo study on modified fat systems has started!

Research on oleogels and their functionality in mice has started at the University of Helsinki Biomedicum animal facilities, designed by docent Fabio Valoppi’s research group in collaboration with docent Teemu Aitta-Aho.

This novel investigation will look for physiological differences between mice fed diets high in oleogels and other fats including their body composition, food-related behaviour, and weight fluctuations, along with other characteristics during a three-month period. These mice will become integral research participants in this study as we depend on information from them to ensure that the developed oleogels are safe to eat, bringing them closer to their possible commercialization.

Although it is vital to understand the impact of the consumption for any given food or ingredient in humans, forecasting their behaviour during digestion is complicated. A meal’s effects on i.e. hormone production, absorption of nutrients and impact on gut microbiota is not easy to predict, and science can only go so far with laboratory models.  In vitro digestions models analyse pH constants, as the gut’s equivalent enzymes and acids are delivered by a set of spatulas and beakers, attempting to mimic the human digestive process. As you can imagine, this process falls short when determining several aspects of the digestion of oleogel-containing food, such as: How much is safe to eat? What kind of hormonal response do they activate? Or how does it affect cholesterol (both good and bad ones) in blood? Certainly, we need to answer these and many other questions before proceeding.

Hopefully this study will run smoothly, allowing us to fill in knowledge gaps about oleogels and supports the data obtained by us and many other food scientists around the world that are looking for healthier substitutes of saturated fats.

Pictures from left to right: mice diet comparison and visual inspection, research assistant M. Sc. Afsane Kazerani collaborating with one study subject.

Freshpack – summary

Freshpack was a Business Finland project that aimed to develop and commercialize an active packaging technology that prevents premature spoilage of fresh produce. This project ended in August 2021 and despite of Covid-19 constraints and other technical challenges we succeeded to show the technology’s capacity to increase the shelf life of berries. We also managed efficiently produce an active material using a spray dryer

We have worked closely with Finnish operators throughout the food distribution chain to identify critical points, that are integral to maintain the quality of fresh products in a commercial environment. In addition to Finland, Freshpack has attracted global interest among operators in the food distribution chain, which shows that there is a real demand for our technology. We have selected a few interesting funding options which will be targeted to develop Freshpack technology further prior to commercialization. The future development will be focused on the management of key reactions, optimization of ingredients, and the manufacturing process which would help us to better answer to the needs defined by our partners within their commercial environment. During the Freshpack project, we also defined the pathway required to get our technology accepted into the European Union’s list of authorized active and intelligent materials.

Although we didn’t manage to produce a minimum viable product within the scope of this project, we all are pleased and driven by the results of the Freshpack project. Stay tuned, we’ll be back!

Creating More Sustainable Cosmetics with Spruce Gum and Birch Gum

The food and the cosmetics industries share some similarities – ingredients are a major one. This research will help both industries by providing them new information about candidate raw materials. Stabilizers, viscosity controlling agents, emulsifiers, to name a few – it’s possible to use the same innovative solutions to provide greener food and cosmetic ingredients. Spruce and birch gum are examples of new promising ingredients that could progress these industries.

A Bachelor of Beauty and Cosmetics (estenomi) student from Laurea University of Applied Sciences, Anne Parkkonen completed her thesis on the use of spruce and birch gum in cosmetics. It was a practical-oriented project and the goal was to plan, formulate and manufacture different kinds of cosmetic products by including spruce or birch gum as an ingredient. The thesis presents the legal regulations related to cosmetics. As previous research is mainly made for food ingredients, using wood gums for cosmetic purposes is a new idea. The thesis provides more detailed information about the legislation behind the use of ingredients/chemicals in cosmetic products.

The emulsion stabilizing features of spruce and birch gums lead Anne’s work to focus on exploring their effect on texture and composition when used in emulsion-based products (e.g. skin creams and serums). Additionally, evidence also indicates these gums have antioxidant, prebiotic, and anti-inflammatory properties. Some very promising findings from these experiments included how spruce and birch gum made a comfortable and pleasant film-like feel and appearance on the skin when the emulsions dried. Spruce and birch gum seemed to have moisture binding properties which are desirable features in many cosmetic products. These findings support the need for further studies on the use of wood gums in cosmetics.

This thesis project was completed under the guidance of Assoc. Prof. Kirsi Mikkonen and Dr. Satu Kirjoranta who study hemicelluloses (spruce and birch gum) and their potential applications. New avenues have been opened from their initial research, expanding into the field of cosmetics, with nine candidate spruce and birch gum-based products created. These products could inspire future research and collaborations with industry in Finland and further abroad to elucidate how to incorporate spruce and birch gum effectively in different applications.

Spruce and birch gum are ingredients from sustainable sources, manufactured using environmentally-friendly technology from wood. This thesis explores just one example of how many small solutions could make the world and its goods more sustainable within a circular economy. There is a need to replace existing ingredients with greener alternatives which are produced locally and from renewable sources. Spruce and birch gum are hopefully an example to support a better future for the cosmetics industry without compromising on product quality. Anne’s thesis will be released later this year. Petri Kilpeläinen from Natural Resources Institute Finland (Luke) is thanked for providing the spruce and birch gum samples for the study.

New analyses to find out the relationship of hemicelluloses to gut health

Investigation of the effect of birch gum on gut health made a giant leap after the university loosened COVID-19 restrictions, and we got back into the lab. We started to develop two different methods for analyzing birch glucuronoxylan. First, we wanted to analyze whether short-chain fatty acid-producing bacteria could utilize birch glucuronoxylan. These short-chain fatty acids produced by gut microbes from some dietary fibers have been found to be beneficial metabolites. They can, for example, protect against colorectal cancer or metabolic syndrome. Although short-chain fatty acids have been investigated in multiple studies, we previously had not measured them from fecal samples. Two methods based on gas chromatography (GC) were tested and modified before we found a protocol that we were happy with.

Birch glucuronoxylan and different diets were analyzed with pyrolysis gas-chromatography mass-spectrometry (pyr-GC/MS). In this way, we could also evaluate the amount and effect of lignin in the diets. The results from both methods have been promising, and we cannot wait for them to be published.

ROCK – building new knowledge to valorize forest resources

ROCK: ROle of lignin Carbohydrate complexes as Key to stable emulsions project has been completed. The project was designed to valorize forest resources, especially those from Nordic forests. Hemicelluloses-rich extracts, obtained by an environmentally-friendly water-extraction method was previously identified as a functional substance for stabilizing emulsions. Although rich in hemicelluloses, they also contain a certain amount of other polysaccharides and lignin co- extracted. When we commenced this project, the reason for the excellent stability performance of hemicellulose extracts as emulsifiers was still unclear and our hypothesis was that at least some of the residual lignins could be covalently linked to the polysaccharides forming so-called lignin-carbohydrates complexes (LCC). Such hybrid composites have two distinct regions, one more hydrophilic (hemicellulose part) and other more hydrophobic (lignin part). As a result, each region can interact with the different phases of the emulsion, possibly explaining the emulsion stability achieved using hemicellulose-based emulsifier. Our main aim was to investigate the presence of LCC in hemicelluloses extract and identify the role of such structures in emulsion stabilization. To do this we investigated the structures and functionalities of hemicelluloses extracts. In the initial part of this study, we characterized various types of hemicelluloses extracts obtained from birch and spruce wood. Using a combination of fractionation and advanced identification techniques, we demonstrated that some of the lignin residues in the extracts were involved in the formation of LCC linkages of various types (i.e., phenylglycoside, benzylether, and gamma-ester). A previous posted blog with these findings can be found here.

Next, we investigated how the different polymer populations in the hemicelluloses extract, including the LCC structures, are distributed between the emulsion phases (i.e., droplet interface and continuous phase) and what aspects drive such distribution. Beyond differences in the appearance (see figure), we discovered that the hemicelluloses populations in the various emulsion phases also differed in terms of their chemical and structural aspects. The residual lignin is a component of fundamental importance for the hemicelluloses orientation during emulsification and for the stability of the emulsions. Moreover, the various LCC structures identified in the hemicelluloses extracts were fractionated between emulsion phases depending of their type. In summary, ROCK provided the cornerstone to better understand the composition of hemicelluloses extracts and their functionality in emulsion, pushing the wood-hemicelluloses a step closer to added-value applications.

The ROCK project was funded by Tandem Forest Value and led by Assoc. Prof. Kirsi Mikkonen (University of Helsinki, Finland) and Prof. Martin Lawoko (Royal Institute of Technology, Sweden).

Unravelling the assembly mechanisms of emulsions: a new collaboration between FoMSci (University of Helsinki), BiCMat-Aalto and BiCMat-UBC groups (Aalto University and University of British Columbia)

We are pleased to announce the launching of a research collaboration between FoMSci (University of Helsinki) and Biobased Colloids and Materials operating both in Aalto University (BiCMat-Aalto) and University of British Columbia, Canada (BiCMat-UBC), led by Prof. Orlando Rojas. This collaboration is boosted by the joining of two postdoctoral researchers, Drs. Mamata Bhattarai and Emilie Ressouche working under the joint supervision of Profs. Rojas and Mikkonen. Mamata finished her PhD from FoMSci in November 2020, and Emilie comes from the Department of Applied Physics, in the Molecular Materials group, led by Prof. Olli Ikkala.

The research topics and the know-how available in both groups are complementary: FoMSci brings expertise in emulsions, hemicelluloses, and food applications.; BiCMat also works with multiphase systems based on lignocellulosic bio-colloids. Together, the groups will investigate the mechanisms responsible for the formation of emulsions stabilized by bio-based compounds such as lignin/hemicellulose complexes, and plant- as well as marine-derived bioresources.

This research project aligns with the goals of the BioElCell Research project, funded by Advanced ERC (2018-2023) in BiCMat, and will also bring an expansion to our Academy of Finland funded ENVISION project, leading to a wider comprehension of emulsions stabilized by wood hemicelluloses.

We nailed it again: four new funded projects to FoMSci

Between November and December 2020 our FoMSci group has received four new grants: three to Fabio Valoppi (iOLEO, ENGEL, and iFOOD), and one to Thao Minh Ho (FinPowder).

Fabio’s projects: The iOLEO and ENGEL projects, funded by the University of Helsinki three-year research grant scheme (7% success rate – only 9 projects were funded among 128 submitted) and the Jane and Aatos Erkko Foundation, respectively. These projects aim to develop new oleogels with body weight managing abilities unlocking the potential of oleogels as multi-functional fat substitutes. Mr. Tiago Pinto has been selected and hired as a new PhD student in the iOLEO project and will begin his work in April 2021. For the other project, ENGEL, we are currently in the process of hiring a postdoctoral researcher. The iFOOD project, funded by HELSUS, aims to develop a new digital tool to simulate mechanical properties of food products using finite element method simulation. This project is based on the existing and fruitful collaboration between FoMSci and the Electronics Research Laboratories (ETLA) also from the University of Helsinki.

Thao’s project: The FinPowder project, funded by the Finnish Natural Resources Research Foundation, aims to design powder particles to protect functional compounds of wild berry during spray drying. These coating materials originate from sustainable and natural sources that are extremely low in calories and cost, namely wood-based celluloses and hemicelluloses. Mr. Abedalghani Halahlah has been selected and hired as our new PhD student to work in the FinPowder project and will join the FoMSci group within a couple of months. Abedalghani will be co-supervised by Associate Professor Kirsi Mikkonen and Dr. Thao Minh Ho, in collaboration with Professor Vieno Piironen.

The cherry on the cake is that thanks to these new projects, our group will now be able to purchase a brand-new lab scale spray dryer!

Even though 2020 has been a tough year, we ended it in the best way possible with new funding, new people joining FoMSci, and new equipment. Writing proposals can be very energy demanding, but the doors that these new projects will open make it worth all the effort we put in during the writing process.

2021 has already started, and new and exciting times are waiting for us ahead!