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.

Slush 2021 helps members of FoMSci to connect with potential investors

In early December 2021, several members of FoMSci participated in Slush 2021. The “world’s leading startup event” was held at the Helsinki Expo and Convention Centre. Slush 2021 gathered 8800 attendees from all over the world with diverse backgrounds, from highly prominent founders and investors to researchers, companies, media, executives, operators, and other talents.

The atmosphere in Slush was very unique compared to other typical conference events. Different colours of lighting with fog filled the air, giving a feeling of being inside a techno-club rather than a conference. The opening ceremony started on the morning of 1st December, a DJ playing techno music with multiple lighting effects and projections on huge screens across the venue. There were four big stages with different talks occurring simultaneously, multiple side events and the surrounding space was filled by booths from different global startups, companies, research centres and universities. Besides, plenty of closed and open-spaced meeting rooms were available for all attendees. This gave the attendees many choices on how to make full use of their time.

Several members of FoMSci who were funded by Business Finland under Research to Business (R2B) projects at different commercialisation stages were invited to attend Slush 2021 by Helsinki Innovation Services (HIS). We were joined by 14 other University of Helsinki’s science-based innovation projects in a specially designed space. Each of our projects was given a table equipped with an iPad to present our innovation to visitors and potential investors. During the two days event, our booths were swamped by many visitors interested in our innovations. This supported our belief about the importance of our innovations for the world’s future. The most notable visitors included the Minister of Science and Education, Antti Kurvinen, and ex-Deputy Prime Minister of Finland, Antti Petteri Orpo. We also maximised the opportunity to meet promising investors from all over the world. “It was an eye-opening experience to interact with investors, learning the important points that they are looking for, and their insights on our innovation”, said Anis Arzami, FoMSci postdoctoral researcher representing FreshTech in Slush 2021.

Here are the project summaries of FoMSci members who attended the event.

  1. OleoFlow: Ari Salmi, Fabio Valoppi and Anton Nolvi. Re-engineering fat to make tasty foods finally healthy. Often tasty foods are unsustainable and most often full of fat and sugar, which can cause weight gain and obesity. OleoFlow offers a solution for consumers to enjoy tasty food without the need to change their diet, by using oleogels which replace unhealthy fat. OleoFlow technology can be functionalised to suit all types of foods and give the consumers a satiety feeling. Besides helping consumers to eat less, OleoFlow is free from chemical modification, easily customisable, sustainable, and vegan. OleoFlow was also showcased at the Slush 2021 side event, Y-Science and the final pitch was presented by Fabio Valoppi.
  2. FreshTech: Anis Arzami and Kirsi Mikkonen. A new innovative packaging technology to reduce the waste of fresh produce. The ripening of fresh vegetables, fruits and berries can be delayed by using FreshTech technology. FreshTech offers a solution to preserve the taste and nutritional quality of fresh produce more effectively compared to currently available packaging solutions. The concept of this technology is based on the controlled production and continuous release of hexanal into the packaging container using a recyclable bio-based, food-grade matrix. The hexanal released from the matrix can maintain the freshness of the produce and inhibits microbial spoilage.
  3. MyShroom: Jutta Varis, Minna Isotupa, Marko Saapunki, Kirsi Mikkonen and Pauliina Lankinen. Mycoprotein as substitutes for animal protein in food. Current meat substitutes available on the market are heavily processed with a long list of ingredients to mask the off-flavours from plant proteins. MyShroom offers a healthier and tastier alternative for current meat substitutes by using mycoprotein, which is a high-quality protein, cheap, sustainable and can be conveniently used by the food industry. MyShroom is suitable for sandwich toppings and as a material to develop other food products.

We had a really nice time at Slush 2021, and we exchanged many interesting ideas with the visitors, not just for the benefit of our current science-based innovation projects, but also for future collaboration opportunities. We received a lot of valuable comments on how to improve our products and how to proceed further to realise our ambition of a start-up company. Overall, being in Slush is a remarkable experience and we wish to attend the event again next year and for years to come.

Special appreciation to HIS for giving us this wonderful opportunity and for coordinating the preparation of the event.

Writing retreat in Lammi 11.-13.10.2021

The Food Materials Science Research Group, reinforced with Prof. Maija Tenkanen and her Carbohydrate Enzymology and Chemistry Group, spent three days at the Lammi Biological Station of the University of Helsinki.

The classroom was reserved for quiet and calm working, where a good flow was achieved with a number of new articles, grants, and reports developed. Many interactive scientific discussions were held outside of the classroom, whether that be in the sauna, over lunch and dinner, or into the evening. Our team was fed with delicious meals: breakfast, lunch, coffee, and dinners. The food was again wonderful, and we could focus all of our energy on writing and data handling.

We picked mushrooms in the Evo forest area and our master mushroom cook, Hongbo fried these up with plenty of vegan margarine over a live fire as an evening snack. Evening sauna and swimming in the fresh cold water in the Pääjärvi lake was very relaxing. Our trip was most enjoyable, after this heavy covid-closure period, as we readjusted to sitting together and having long evening discussions about science and more with real, living people.

A couple of highlights:

In the writing retreat of 2019, Fabio introduced to the group a modern idea about writing an article together in 24 hours. Unbelievably, the outcome was not quite as easy and fast. Thanks to Fabio’s ongoing dedication to the 24-hour paper, now, after 24 months, we finally celebrated publishing our review article:

Valoppi, F., Agustin, M., Abik, F., Morais de Carvalho, D., Sithole, J., Bhattarai, M., Varis, JJ, Arzami, A., Pulkkinen, EE, & Mikkonen, KS. Insight on current advances in food science and technology for feeding the world population. Frontiers in sustainable food systems.

We got also joyful news from other accepted articles:

Kuribayashi, T., Lankinen, P., Hietala, S., Mikkonen, K.S. Dense and continuous networks of aerial hyphae improve flexibility and shape retention of mycelium composite in the wet state. Composites Part A, accepted.

Hagel, S., Lüssenhop, P., Walk, S., Kirjoranta, S., Ritter, A., Bastidas Jurado, C., Mikkonen, K.S., Tenkanen, M., Körner, I., Saake, B. Valorization of urban street tree pruning residues in biorefineries by steam refining: conversion into fibers, emulsifiers and biogas. Frontiers in Chemistry, accepted.

Mushroom foraging in Sipoonkorpi National Park

Hunting for mushrooms in Finnish forests is a peaceful and unique pastime. Food Materials Science Research Group, along with family members and research collaborators experienced a wonderful day in Sipoonkorpi National Park. We were joined by Milla Koponen who is a self-taught mushroom identifier and has been fascinated by the world of fungus since she was a teenager. A major part of her youth was spent living in a little village in Eastern Finland, so the forest and the many mushrooms hiding within have played a great role in her life.

Walking through the damp forest, our eye catches a glimpse of white, golden yellow, and brownish mushrooms at the foot of an old birch. There is no general rule on how to recognize edible mushrooms from the poisonous ones, and to classify them requires extensive knowledge and experience about mushrooms. Therefore, we decided to pick samples of almost all the mushrooms, with the exception of the smallest of mushrooms, we encountered on our trek. After two hours of foraging, we gathered together at a campfire to enjoy grilled sausages (and mustard) while listening to music served by a professional musician, Riku Turpeinen. During this time, Ms. Koponen taught many of us to identify specific edible mushrooms, and how to cook them.

No matter what types of mushrooms and how many mushrooms we picked, the hunted mushrooms were so precious to us as it was the first time for many of us to have the opportunity to pick mushrooms in this foragers paradise. A big thank you to Jutta Varis who organized the trip, we had such a nice time enjoying Finnish nature, learning how to identify mushrooms, and particularly the delicious mushroom meals we created with the edible species we returned home with.

Picture from left to right:

Relaxing time at the campfire site with grilled sausage and music served by Riku Turpeinen after two hours foraging for mushrooms in the forest.

The identification and classification of hunted mushrooms with the help by Milla Koponen.

The tasty edible mushrooms including porcini mushrooms, several types of brittlegill mushrooms, and common puffball mushrooms. Findings also included salmon coral mushrooms which were not edible but a fun discovery as it indeed looks like coral.

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!

Mamata Bhattarai (PhD) was awarded the inaugural best dissertation prize by The Finnish Natural Resources Research Foundation

The awarded thesis was titled;


Mamata was presented by the foundation with the 10,000€ award for the doctoral thesis that best advance’s the foundations goal at the annual festive gathering held at Demo in Helsinki. She completed her PhD at the Department of Food and Nutrition, University of Helsinki in December 2020 under the supervision of Associate Professor Kirsi Mikkonen.

Renewable and biodegradable plant polysaccharides, such as wood hemicelluloses are envisioned to be used as future raw materials in consumer products, including food or pharmaceuticals. Mamata’s research explored softwood hemicelluloses from spruce (galactoglucomannans; GGM). GGM obtained from different recovery approaches are currently finding applications as emulsifiers and stabilizers of dispersed systems. Their associative properties are affected by the recovery approach since it influences purity and intrinsic characteristics (e.g., molar mass, degree of substitution). The novelty of Mamata’s study findings lies in linking the solution properties of aqueous wood hemicelluloses with their functionality in emulsions, namely, interfacial morphology and stability. Understanding the impact of the GGM recovery approach on its associative behavior, currently limited, is essential to comprehend the stabilization mechanism of GGM in dispersed systems as well in the expansion of its functional applications

The most important finding from this study is that polysaccharide “solubility” plays an important role in interfacial structures and emulsion stability. The former can be tailored with recovery procedures, which provides a unique opportunity to fabricate polysaccharide-based particles. Currently, novel biomaterials are being developed from wood biomass. The findings of this study contributed to the characterization of GGM’s structure at a nanometric scale, thereby enhancing its scope for future applications. These findings would also be relevant in existing operations of paper and pulping industries, as well as for aspiring biorefineries in identifying optimal GGM recovery approach.

The Food Material Science Group would like to warmly congratulate Dr. Mamata Bhattarai for her outstanding contribution to the field during her early research career and look forward to tracking her progress into the future.

Publications arising from Mamata’s thesis work

  1. Bhattarai M, Kontro I, Sulaeva I, Valoppi F, Potthast A, Mikkonen KS. Polymerparticle features of polysaccharides determine emulsion stability and interfacial morphology.
  2. Bhattarai M, Sulaeva I, Pitkänen L, Kontro I, Tenkanen M, Potthast A, Mikkonen KS. Colloidal features of softwood galactoglucomannans-rich extract. Carbohydr. Polym. 2020a, 241:116368
  3. Bhattarai M, Valoppi F, Hirvonen SP, Hietala S, Kilpelainen PO, Aseyev V, Mikkonen KS. Time-dependent self-association of spruce galactoglucomannans depends on pH and mechanical shearing. Food Hydrocoll. 2020, 102:105607
  4. Bhattarai M, Pitkanen L, Kitunen V, Korpinen R, Ilvesniemi H, Kilpelainen PO, Lehtonen M, Mikkonen KS. Functionality of spruce galactoglucomannans in oilin-water emulsions. Food Hydrocoll. 2019, 86:154-161.

The Finnish Natural Resources Research Foundation Award information


To encourage young doctoral students to engage in research related to the sustainable use of Finland’s natural resources, the Foundation annually presents a €10,000 award to a doctoral thesis that best advances the Foundation’s goals. The foundation evaluates nominations based on The award-winning doctoral thesis must be of an internationally high standard and create opportunities to develop the utilization of Finland’s natural resources in compliance with the principles of sustainable development. The thesis must have been approved by a Finnish university. The evaluation criteria include the scientific-technical novelty and commercial potential of the results, as well as the advancement of the principles of sustainable development and resource-efficiency in the use of natural resources.

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.

Members of FoMSci Participated in the ACS Spring 2021 Conference

The American Chemical Society (ACS) annually hosts two major conferences on chemistry, one in the spring and the other in the autumn. Members of the Food Materials Science group in the University of Helsinki have regularly participated in the ACS Spring events since 2005 to present the results of our work. While the ACS Spring 2020 was cancelled due to the coronavirus pandemic, in 2021 the conference was held entirely online via Zoom, with live presentation sessions being held on April 5th-16th and on-demand sessions between April 19th-30th. Several of our members received the opportunity to present our research in the oral presentation sessions. Below is the list of presentation titles and the contributing authors, with the presenters in bold:

  1. Hardwood xylans show prebiotic effect on rodents – Emma Kynkäänniemi, Maarit Lahtinen, Ching Jian, Anne Salonen, Kirsi S. Mikkonen, Anne-Maria Pajari
  2. Comparative emulsion stability study of hot water-extracted birch glucuronoxylans – Felix Abik, Thao Minh Ho, Kirsi S. Mikkonen
  3. Lignin nanoparticles and nanocelluloses for the removal of pharmaceutical residues from water – Melissa Agustin, Mari Lehtonen, Kirsi S. Mikkonen
  4. Green route fabrication approaches of lignin nanoparticles: a comparison study – Patricia Figueiredo, Melissa Agustin, Maarit Lahtinen, Sami-Pekka Hirvonen, Paavo Penttilä, Kirsi S. Mikkonen
  5. Analytical insights on lignin-carbohydrate complexes in softwood and hardwood extracts – Danila Morais de Carvalho, Maarit Lahtinen, Martin Lawoko, Kirsi S. Mikkonen

We normally would have attended the conference live in the United States, but as it was held entirely online, we could participate without having to travel from Finland to the United States. The format also allowed us to watch the presentations that we found interesting, despite being spread across different divisions, and move between the different parallel sessions seamlessly. For example, most of us were involved in the Division of Cellulose and Renewable Materials (CELL), but we could easily switch to sessions within the Division of Colloid and Surface Chemistry (COLL), Agricultural and Food Chemistry (AGFD), or Analytical Chemistry (ANYL), to name a few. This allowed us to listen to various topics of our choice, maximizing the insight we got from the conference.

However, the sessions were organized based on the Pacific Daylight Time, which is 10 hours behind our current Eastern European Summer Time in Finland. Therefore, the sessions of the day began at 7 PM Helsinki time, and closed early in the morning. Consequently, a special mention goes to those  who had to present in the early hours of the morning. It also became rather difficult to watch the presentations that were scheduled later in the day. Nevertheless, an option to allow presenters to open their presentations to be available for on-demand viewing until April 30th was available, which allowed us to watch many of the presentations that we missed, was in parallel with other presentations, or even fell asleep while watching due to the late hours.

Overall, despite missing the direct interaction aspect of traditional conferences, we still managed to obtain as much knowledge and experience as we can from ACS Spring 2021. We look forward to our next participation in an ACS Meeting!