Category Archives: food

Fluid mechanics in the kitchen

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Caption: Dr. Maciej Lisicki is developing a formula for perfectly creamy ice cream in his laboratory. Credit Photo: Michal Czerepaniak, source: Faculty of Physics, University of Warsaw.

It’s unusual to see a scientist in an orange (maybe it could be called fire engine red?) jumpsuit as it has an altogether different meaning (prison wear) in the US.

Sadly, there isn’t a video of Dr. Maciej Lisicki or other scientists in the kitchen but here’s a description of what they’ve been up to from a June 22, 2023 University of Warsaw (Poland) press release (also on EurekAlert),

Take four brilliant physicists who specialize in fluid mechanics and put them in the kitchen. Give them pots, pans, basic foodstuffs, and a bottle of champagne. Add a COVID-19 pandemic, a pinch of boredom, and a handful of good ideas. Stir, wait, and voilà – you have a “delicious” publication that will teach you how bubbles are created in champagne, how to brew the perfect espresso, and how “kitchen revolutions” can contribute to innovations in many fields, including biomedicine and nanotechnology.

Most of us visit this place every day. But the kitchen is not just for cooking meals. “It can be an excellent place to conduct experiments and even make scientific discoveries,” argues Maciej Lisicki, of the Faculty of Physics of the University of Warsaw, co-author of a publication in the prestigious journal Reviews of Modern Physics. The team of researchers, which in addition to Maciej Lisicki includes Arnold Mathijssen of the University of Pennsylvania, Endre J.L. Mossige of the University of Oslo and Vivek N. Prakash of the University of Miami, not only explores the history of food science, but also shows how phenomena in the kitchen lead to innovations in biomedicine and nanotechnology.

COVID pandemic and bubbles in champagne

Maciej Lisicki and his fellow researchers began working on the article during the COVID-19 pandemic, when many researchers could not work in the lab and began experimenting in their homes. “It started primarily with the intention to make an educational tool, given that kitchens offer a low barrier of entry to doing science — all you need are some pots, pans, and a few ingredients to get a few reactions going—but it quickly grew into a more scientific reflection of the history of food once we realized how interwoven the fields are,” says Arnold Mathijssen.

The team of researchers constructed the results of their work along the lines of a menu. “Tasting” begins with the physics of drinks and cocktails, then moves on to main courses, and finishes with coffee and desserts, whose preparation is also based on the intuitive use of the laws of nature.

As with any good party, everything begins with the opening of a bottle of champagne. After a characteristic “pop”, we observe how a mist forms around the neck of the bottle. – This phenomenon is associated with a rapid change in pressure. Inside the bottle it reaches almost five atmospheres, but when the bottle is opened it drops to one atmosphere.  “The expansion is accompanied by a drop in temperature, which causes the water vapor that accumulates near the mouth of the bottle to freeze, and the carbon dioxide coming out of the bottle to condense”, Maciej Lisicki explains.

In their paper, the researchers also look at bubbles, which give sparkling wines their unique flavor. “Circulating bubbles force the transport of the liquid in the glass, and thus facilitate the release and spread of aromatic notes and flavors”, the researcher adds. From the section of the paper devoted to drinks and cocktails, we will also learn what makes the foam in beer so thick and stable, why aniseed drinks such as rakija and ouzo get cloudy when enough water is added (the phenomenon is even called the “ouzo effect”), and what “tears of wine” are.

When water surfs the pan

Moving on to the main course, the scientists explain the role of heat and its effect on food textures, aromas, and flavors. Among other things, they describe the Leidenfrost effect, in which a drop of liquid placed on a very hot surface forms an insulating layer of vapor, that prevents rapid boiling. “Water drops thrown onto the pan ‘surf’ and even bounce off the surface, instead of evaporating immediately”, Lisicki says. 

Proper temperature is crucial in the preparation of many foods. “It doesn’t take a Ph.D. in physics to fry the perfect steak. Everyone knows that one needs to quickly sear the meat in a sufficiently hot pan. As a result, the proteins on the surface of the steak coagulate and the moisture is kept inside”, the researcher explains. 

A Ph.D. in dishwashing

The text also includes examples of scientific discoveries that researchers have made without leaving their own kitchens. One of them is related to the biography of Agnes Pockels.

“Her story speaks of the inequality in science. She was a woman in Germany in the late 19th century, so she was not allowed to attend university for formal training, making it difficult for her to submit her research to journals,” Mathijssen says.

Running her parents’ household and spending a lot of time in the kitchen, she quickly began experimenting there. “Observing the formation of foam and films on the surface of dirty dishes, she was the first to describe the phenomenon of surface tension and developed an instrument to measure it. Initially, scientific journals were reluctant to publish the results of her experiments due to her lack of formal training and affiliation with university staff. Her first paper was published through Lord Rayleigh in Nature and contributed to the understanding of surface effects in liquids. Agnes Pockels then became well-known and respected, and all her subsequent work was published in high-profile journals. This example shows that it is possible to become a respected scientist without leaving home,” notes Maciej Lisicki.

Salad dressing vs. nanoengineering

Research in fluid mechanics can help improve food processing technologies, as well as find applications in other fields such as nanoengineering and medicine. “In an earlier study (“Rechargeable self-assembled droplet microswimmers driven by surface phase transitions”, published in Nature Physics) conducted by my team, we used a simple emulsion that is the basis of salad dressings – oil with water. We were able to make droplets of such an emulsion, with the addition of a surfactant, form tendrils under temperature and move like bacteria. Such nontoxic, biocompatible microfluidics could be used in the future, for example, to precisely deliver drugs anywhere in our bodies”, Lisicki explains. 

The review also highlights the applicability of these technologies in areas such as food safety and quality control. By deploying devices that can detect food-borne pathogens or toxins using principles of fluid dynamics, the scientific community can contribute significantly to public health.

Another key aspect of their review is the potential impact it could have on policy decisions, particularly those related to environmental sustainability and food safety. The authors highlight the significance of science-based policies, for example – referencing the announced EU ban on PFAS non-stick coatings by 2030. Using the scientific understanding offered by studies like these, policy makers can make informed decisions to foster a more sustainable and safer food future.

“Kitchen flows show us that significant scientific problems are available at our fingertips and do not always require space technology to explore them. On the other hand, more than a few cosmic technologies were born from inspiration by everyday phenomena. The kitchen can therefore entertain us, but also teach us – in this case, physics. This is why it is worth a try to unleash your curiosity and experiment!” Lisicki adds.

This research was supported by the United States Department of Agriculture (USDA-NIFA AFRI 2020-67017-30776 and 2020-67015-32330).

Faculty of Physics of the University of Warsaw
Physics and astronomy at the University of Warsaw appeared in 1816 as part of the then Faculty of Philosophy. In 1825, the Astronomical Observatory was established. Currently, the Faculty of Physics at the University of Warsaw consists of the following institutes: Experimental Physics, Theoretical Physics, Geophysics, the Department of Mathematical Methods and the Astronomical Observatory. The research covers almost all areas of modern physics, on scales from quantum to cosmological. The Faculty’s research and teaching staff consists of over 200 academic teachers, 88 of whom are professors. About 1,100 students and over 170 doctoral students study at the Faculty of Physics at the University of Warsaw.

Perhaps the paper provides more information about the ice cream research depicted in the visual image at the top of this posting. Here’s a link to and a citation for the paper,

Culinary fluid mechanics and other currents in food science by Arnold J. T. M. Mathijssen, Maciej Lisicki, Vivek N. Prakash, and Endre J. L. Mossige. Rev. Mod. Phys. Vol. 95, Iss. 2 — April – June 2023 025004 DOI: https://doi.org/10.1103/RevModPhys.95.025004 Published: 5 June 2023 © 2023 American Physical Society

This paper is behind a paywall.

Gene-edited food: better tasting and/or allergen-free?

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I have two items about gene-edited food. One is from the Canadian Broadcasting Corporation (CBC) and the other is from Hiroshima University (Japan).

Better tasting food?

Cherries without pits do not fit my definition of better tasting food but it’s just one of the touted ‘improvements’.

https://i.cbc.ca/1.6513602.1684353993!/fileImage/httpImage/image.jpg_gen/derivatives/16x9_780/a-little-dirt-never-hurt-01.jpg
Can you imagine eating cherries without having to deal with its pits? That could be a reality thanks to gene-editing tools like CRISPR. (Ben Nelms/CBC)

A May 18, 2023 article by Mouhamad Rachini for CBC’s radio programme, The Current, features information from a radio segment on gene-edited food,

When Michael Wolf tried a new type of mustard green that had been gene-edited to taste less bitter, he came away impressed.

“I don’t necessarily like my food very bitter, so I appreciated it,” Wolf, founder of the food tech publication The Spoon, told The Current’s Matt Galloway.

Food scientists are starting to use gene-editing technology, called CRISPR [clustered regularly interspaced short palindromic repeats], to change certain features of some Canadians’ favourite fruits and vegetables. For example, scientists told Wolf that the technology could be used to create cherries without a pit.

Pairwise, a North Carolina-based gene-editing startup, recently rolled out a mustard green engineered to be less bitter than the original plant. It’s the first CRISPR-edited food to hit the U.S. market. 

Although the gene-edited mustard greens haven’t appeared in Canada yet, the process could find a home here very soon.

Earlier this month, Minister of Agriculture and Agri-Food Marie-Claude Bibeau announced that the Canadian Food Inspection Agency (CFIA) seed guidelines now allow for some modified plants.

The updated rules now allow seeds created through gene-editing without an independent safety assessment by the government, as long as they aren’t spliced with DNA from other types of fruits or vegetables, or altered to make them pesticide-resistant. [emphasis mine]

Wolf explained further that gene-editing with CRISPR has some key differences from other types of genetic modification for food, which has been around for some time.

“[With genetic modification], you’re maybe inserting a foreign DNA into a molecule. But with CRISPR, what it’s essentially doing is just cutting out undesirable traits,” he said. [emphasis mine]

“So you’re not really inserting something that might be foreign to the organism. So it’s something that is a bit, I guess, less concerning for a lot of people who are worried about GMO because that takes away that concern.” [emphasis mine]

…

“Removing bitterness in a vegetable, I believe, is doing a disservice to our palate,” Dionisia Roman-Osicki of Virden, Man., wrote to The Current. “You can’t be a foodie without recognizing the value of bitterness in food.”

Organic farmer Antony John said there are already “cultural methods” to sweeten the taste and nutritional values of certain foods without genetic modification, such as carrots.

“The cold temperatures causes the carrots to provide an antifreeze, and that antifreeze is sugar,” said John, co-owner of the Soiled Reputation farm in Sebringville, Ont. “So they convert the starch in their roots into sugars. So letting your carrots grow when it’s cold and when there’s subzero temperatures will enhance the sugar in it.”

…

The radio segment embedded in Rachini’s May 18, 2023 article is 13 mins. 14 secs.

Allergen-free eggs

Over at Hiroshima University, a May 17, 2023 press release (also on EurekAlert but published May 16, 2023) announces research into making eggs safer for people who have allergies, Note 1: The researchers have used a different kind of gene-editing (or genome-editing) technique Note 2: Links have been removed,

Researchers have developed a chicken egg that may be safe for people with egg white allergies. Chicken egg allergies are one of the most common allergies in children. Though most children outgrow this allergy by age 16, some will still have an egg allergy into adulthood. Egg white allergies can cause a variety of symptoms, including vomiting, stomach cramps, breathing problems, hives, and swelling and some people with egg white allergies are unable to receive certain flu vaccines.

Using genome editing technology, researchers have produced an egg without the protein that causes egg white allergies. This protein, called ovomucoid, accounts for approximately 11% of all the protein in egg whites.

Research detailing the food safety profile of this modified egg, called the OVM-knockout, was detailed in a paper published in Food and Chemical Toxicology in April 2023.

“To use OVM-knockout chicken eggs as food, it is important to evaluate its safety as food. In this study, we examined the presence or absence of mutant protein expression, vector sequence insertion, and off-target effects in chickens knocked out with OVM by platinum transcription activator-like effector nucleases (TALENs),” said Ryo Ezaki, an assistant professor at the Graduate School of Integrated Sciences for Life at Hiroshima University in Hiroshima, Japan. TALENs are restriction enzymes that recognize specific DNA sequences and break or cut them.

In order to develop the OVM-knockout eggs, researchers needed to detect and eliminate the ovomucoid protein in the egg whites. TALENs were engineered to target a piece of RNA called exon 1, which codes for specific proteins. The eggs produced from this technique were then tested to ensure there was no ovomucoid protein, mutant ovomucoid protein, or other off-target effects. The eggs had the desired frameshift mutation, which is a mutation created by inserting or deleting nucleotide bases in a gene, and none of them expressed mature ovomucoid proteins. Anti-ovomucoid and anti-mutant ovomucoid antibodies were used to detect any traces of the protein, but there was no evidence of ovomucoid in the eggs. This means that mutant ovomucoids could not create new allergens. This is an important step in determining the safety profile of the eggs.

Other gene editing tools, such as CRISPR, tend to have off-target mutagenesis effects. This means that new mutations are prompted by the gene editing process. However, whole genome sequencing of the altered egg whites showed mutations, which were possibly off-target effects, were not localized to the protein-coding regions.

“The eggs laid by homozygous OVM-knockout hens showed no evident abnormalities. The albumen contained neither the mature OVM nor the OVM-truncated variant,” said Ezaki. “The potential TALEN-induced off-target effects in OVM-knockout chickens were localized in the intergenic and intron regions. Plasmid vectors used for genome editing were only transiently present and did not integrate into the genome of edited chickens. These results indicate the importance of safety evaluations and reveal that the eggs laid by this OVM knockout chicken solve the allergy problem in food and vaccines.”

Looking ahead, researchers will continue to verify the safety profile of the OVM-knockout eggs. Because some people are highly allergic to this specific protein, even small amounts of ovomucoid can cause a reaction. Researchers will need to perform additional immunological and clinical studies to determine the safety of the OVM-knockout eggs. At this time, researchers have determined that OVM-knockout eggs are less allergenic than standard eggs and can be safely used in heat-processed foods that patients with egg allergies can eat. “The next phase of research will be to evaluate the physical properties and processing suitability of OVM-knockout eggs, and to confirm their efficacy through clinical trials,” said Ezaki. “We will continue to conduct further research toward the practical application of allergy-reduced eggs.”

Here’s a link to and a citation for the paper,

Transcription activator-like effector nuclease-mediated deletion safely eliminates the major egg allergen ovomucoid in chickens by Ryo Ezaki, Tetsushi Sakuma, Daisuke Kodama, Ryou Sasahara, Taichi Shiraogawa, Kennosuke Ichikawa, Mei Matsuzaki, Akihiro Handa, Takashi Yamamoto & Hiroyuki Horiuchi. Food and Chemical Toxicology Volume 175, May 2023, 113703 DOI: https://doi.org/10.1016/j.fct.2023.113703

This paper is open access.

Fairy-like robot powered by wind and light

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Caption: For their artificial fairy, Hao Zeng and Jianfeng Yang got inspired by dandelion seeds. Credit: Jianfeng Yang / Tampere University

That image makes me think of Tinker Bell (the fairy in the novel/play/movie with ‘Peter Pan’ in its titles) but I can also see how the researchers were inspired by dandelion seeds, which we used to call ‘wishes’.

Dandelion Seeds Free Stock Photo – Public Domain Pictures

A January 30, 2023 news item on ScienceDaily announces the fairy-like robot,

The development of stimuli-responsive polymers has brought about a wealth of material-related opportunities for next-generation small-scale, wirelessly controlled soft-bodied robots. For some time now, engineers have known how to use these materials to make small robots that can walk, swim and jump. So far, no one has been able to make them fly.

Researchers of the Light Robots group at Tampere University [Finland] are now researching how to make smart material fly. Hao Zeng, Academy Research Fellow and the group leader, and Jianfeng Yang, a doctoral researcher, have come up with a new design for their project called FAIRY — Flying Aero-robots based on Light Responsive Materials Assembly. They have developed a polymer-assembly robot that flies by wind and is controlled by light.

…

A January 26, 2023 Tampere University press release (also on EurekAlert but published January 30, 2023), which originated the news item, elucidates why the researchers are excited about their work,

Superior to its natural counterparts, this artificial seed is equipped with a soft actuator. The actuator is made of light-responsive liquid crystalline elastomer, which induces opening or closing actions of the bristles upon visible light excitation,” explains Hao Zeng.

The artificial fairy is controlled by light

The artificial fairy developed by Zeng and Yang has several biomimetic features. Because of its high porosity (0.95) and lightweight (1.2 mg) structure, it can easily float in the air directed by the wind. What is more, a stable separated vortex ring generation enables long-distance wind-assisted travelling.

“The fairy can be powered and controlled by a light source, such as a laser beam or LED,” Zeng says.

This means that light can be used to change the shape of the tiny dandelion seed-like structure. The fairy can adapt manually to wind direction and force by changing its shape. A light beam can also be used to control the take-off and landing actions of the polymer assembly.

Potential application opportunities in agriculture

Next, the researchers will focus on improving the material sensitivity to enable the operation of the device in sunlight. In addition, they will up-scale the structure so that it can carry micro-electronic devices such as GPS and sensors as well as biochemical compounds.

According to Zeng, there is potential for even more significant applications.

“It sounds like science fiction, but the proof-of-concept experiments included in our research show that the robot we have developed provides an important step towards realistic applications suitable for artificial pollination,” he reveals.

In the future, millions of artificial dandelion seeds carrying pollen could be dispersed freely by natural winds and then steered by light toward specific areas with trees awaiting pollination.

“This would have a huge impact on agriculture globally since the loss of pollinators due to global warming has become a serious threat to biodiversity and food production,” Zeng says.

Challenges remain to be solved

However, many problems need to be solved first. For example, how to control the landing spot in a precise way, and how to reuse the devices and make them biodegradable? These issues require close collaboration with materials scientists and people working on microrobotics.

The FAIRY project started in September 2021 and will last until August 2026. It is funded by the Academy of Finland. The flying robot is researched in cooperation with Dr. Wenqi Hu from Max Planck Institute for Intelligent Systems (Germany) and Dr. Hang Zhang from Aalto University.

Here’s a link to and a citation for the paper,

Dandelion-Inspired, Wind-Dispersed Polymer-Assembly Controlled by Light by Jianfeng Yang, Hang Zhang, Alex Berdin, Wenqi Hu, Hao Zeng. Advanced Science Volume 10, Issue 7 March 3, 2023 2206752 DOI: https://doi.org/10.1002/advs.202206752 First published online: 27 December 2022

This paper is open access.

Keanu Reeves molecule: protector of plants?

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Courtesy: Wallpaperstopick [downloaded from https://wallpaperstopick.blogspot.com/2012/05/keanu-reeves.html]

The Keanu Reeves molecule is produced by bacteria.according to a February 6, 2023 news item on phys.org,

Bacteria of the genus Pseudomonas produce a strong antimicrobial natural product, as researchers at the Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI) have discovered. They proved that the substance is effective against both plant fungal diseases and human-pathogenic fungi. The study was published in the Journal of the American Chemical Society and highlighted in an editorial in Nature.

…

A February 6, 2023 Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute (Leibniz-HKI) press release (also on EurekAlert) by Charlotte Fuchs, which originated the news item, highlights both the published study and the special article in Nature magazine, Note: A link has been removed,

The newly discovered natural product group of keanumycins in bacteria works effectively against the plant pest Botrytis cinerea, which triggers grey mould rot and causes immense harvest losses every year. But the active ingredient also inhibits fungi that are dangerous to humans, such as Candida albicans. According to previous studies, it is harmless to plant and human cells.

Keanumycins could therefore be an environmentally friendly alternative to chemical pesticides, but they could also offer an alternative in the fight against resistant fungi. “We have a crisis in anti-infectives,” explains Sebastian Götze, first author of the study and postdoc at Leibniz-HKI. “Many human-pathogenic fungi are now resistant to antimycotics – partly because they are used in large quantities in agricultural fields.”

Deadly like Keanu Reeves

The fact that the researchers have now found a new active ingredient in bacteria of the genus Pseudomonas is no coincidence. “We have been working with pseudomonads for some time and know that many of these bacterial species are very toxic to amoebae, which feed on bacteria,” says study leader Pierre Stallforth. He is the head of the department of Paleobiotechnology at Leibniz-HKI and professor of Bioorganic Chemistry and Paleobiotechnology at Friedrich Schiller University in Jena. It appears that several toxins are responsible for the deadly effect of the bacteria, of which only one was known so far. In the genome of the bacteria, the researchers have now found biosynthesis genes for the newly discovered natural products, the keanumycins A, B and C. This group of natural products belongs to the nonribosomal lipopeptides with soap-like properties.

Together with colleagues at the Bio Pilot Plant of the Leibniz-HKI, the researchers succeeded in isolating one of the keanumycins and conducting further tests. “The lipopeptides kill so efficiently that we named them after Keanu Reeves because he, too, is extremely deadly in his roles,” Götze explains with a wink.

The researchers suspected that keanumycins could also kill fungi, as these resemble amoebas in certain characteristics. This assumption was confirmed together with the Research Centre for Horticultural Crops at the University of Applied Sciences Erfurt. There, Keanumycin was shown to be effective against grey mould rot on hydrangea leaves. In this case, culture fluid that no longer contained bacterial cells was sufficient to significantly inhibit the growth of the fungus.

“Theoretically, the keanumycin-containing supernatant from Pseudomonas cultures could be used directly for plants,” says Götze. Further testing will be carried out together with the colleagues in Erfurt. Keanumycin is biodegradable, so no permanent residues should form in the soil. This means that the natural product has the potential to become an environmentally friendly alternative to chemical pesticides.

Fungal diseases such as Botrytis cinerea, which causes grey mould rot, cause immense harvest losses in fruit and vegetable cultivation every year. More than 200 different types of fruit and vegetables are affected, especially strawberries and unripe grapes.

Possible applications in humans

“In addition, we tested the isolated substance against various fungi that infect humans. We found that it strongly inhibits the pathogenic fungus Candida albicans, among others,” says Götze.

Instead of plants, Keanumycin could therefore possibly also be used in humans. According to the tests conducted so far, the natural product is not highly toxic for human cells and is already effective against fungi in very low concentrations. This makes it a good candidate for the pharmaceutical development of new antimycotics. These are also urgently needed, as there are very few drugs against fungal infections on the market.

The work was supported by the Werner Siemens Foundation, the Leibniz Association and the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) as part of the Balance of the Microverse Cluster of Excellence, and funded by the Dr. Illing Foundation.

The study was highlighted by Nature in a “News & Views” article.

Here are citations and links to both the published study and the article in Nature,

Ecological Niche-Inspired Genome Mining Leads to the Discovery of Crop-Protecting Nonribosomal Lipopeptides Featuring a Transient Amino Acid Building Block by Sebastian Götze, Raghav Vij, Katja Burow, Nicola Thome, Lennart Urbat, Nicolas Schlosser, Sebastian Pflanze, Rita Müller, Veit G. Hänsch, Kevin Schlabach, Leila Fazlikhani, Grit Walther, Hans-Martin Dahse, Lars Regestein, Sascha Brunke, Bernhard Hube, Christian Hertweck, Philipp Franken, and Pierre Stallforth. J. Am. Chem. Soc. 2023, 145, 4, 2342–2353 DOI: https://doi.org/10.1021/jacs.2c11107 Publication Date:January 20, 2023 Copyright © 2023 The Authors. Published by American Chemical Society

and

Bacterial defence repurposed to fight blight (News and Views article) by Andrew Mitchinson. Nature 614, 39 (2023) DOI: https://doi.org/10.1038/d41586-023-00195-x Published: 30 January 2023

Both the study and the ‘News and Views’ article are behind a paywall.

Measure the maturity of cask-aged whisky with gold nanoparticle test

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it’s not altogether a surprise that this research on whisky has Scottish origins. From an October 11, 2022 news item on Nanowerk (Note: A link has been removed),

Researchers at a Scottish university have found a way to use gold nanoparticles to measure the maturity of whisky, which could help distillers with one of the key challenges in the production process (ACS Applied Nano Materials, “Growth of Plasmonic Nanoparticles for Aging Cask-Matured Whisky”).

Chemists and bioscientists from the University of Glasgow developed the test, which harnesses a unique property of cask-aged whisky to measure its maturity.

…

An October 11, 2022 University of Glasgow press release, which originated the news item, delves further into the work,

Each variety of whisky gains some of its colour flavour profile from being stored in wooden casks while it matures over a period of months or years. The flavour of the final product is created by a complex mix of factors known as ‘congeners’ – chemicals left in the spirit after it is distilled and other chemicals absorbed from the wood casks, which react with oxygen over time.

The unpredictable interactions of congeners, along with other factors like the size and shape of the cask and the number of times it has been used before, mean that each cask matures in its own way, and in its own time.

To ensure the consistency of their products, distillers employ highly experienced master blenders. They regularly sample the casks to check the whisky’s readiness for blending, bottling and sale as either a single malt or a mixed blend – a laborious and expensive task.

The researchers set out to develop a test which could do some of the work of the master blenders by using chemical reactions to determine the maturity or ‘age’ of whisky samples.

They built their test on a reaction which occurs when samples of whisky are mixed with a solution containing small quantities of a special type of gold. A chemical reaction in the whisky causes distinctively-coloured gold nanoparticles to form in the sample over a short period of time at room temperature.

The researchers mixed the gold solution with samples from 15 different whiskies distilled in Scotland, Japan and the US. They also tested multiple samples taken at regular intervals from a single cask over a period of six years, which were supplied by the Scotch Whisky Research Institute.

By measuring a property of each sample known as its localised surface plasmon resonance, they found that the unique chemical composition of the whiskies resulted in the creation of gold nanoparticles with distinctly different shapes, sizes and colours in each sample.

They also discovered that the speed of the production of the nanoparticles was connected with its maturity – the faster the nanoparticles formed, the more mature the whisky was.

The results suggest that the process could be used to develop a quick, reliable test for distillers to measure the maturity of their whiskies, reducing the need for master blenders to be involved in every step of the process.

Dr Will Peveler, of the University of Glasgow’s School of Chemistry, is the paper’s lead author. Dr Peveler said: “Age is more than just a number when it comes to whisky – the complex chemical reactions which occur in each cask make it impossible to estimate whisky’s maturity of flavour simply based on how long it’s been ageing.

“For as long as there’s been a whisky industry, distillers have been trying to find better ways to measure the maturity of individual casks to help them understand when they will be ready to use in a single malt or a mixed blend.

“What we’ve been able to do for the first time is show that the ageing-related chemistry of the whisky controls the formation of gold nanoparticles. That has allowed us to develop a unique ‘fingerprint’ not just for types of whisky we tested but also for how whiskies mature over time.

Co-author Dr Jenny Gracie, also of the School of Chemistry, added: “Currently, there are a number of other tests available to measure whisky maturity, which use specialist processes like chromatography and mass spectrometry. However, they are rarely available on the warehouse floor, and if samples have to be sent offsite for analysis, this slows everything down.

“We hope that in the future we can develop this initial finding into a quick, easy and portable kit that distillers can use to measure the maturity of their whiskies without having to send samples for time-consuming tests with specialist equipment.”

Here’s a link to and a citation for the paper,

Growth of Plasmonic Nanoparticles for Aging Cask-Matured Whisky by Jennifer Gracie, Francesco Zamberlan, Iain B. Andrews, Brian O. Smith, and William J. Peveler. ACS Appl. Nano Mater. 2022, XXXX, XXX, XXX-XXX DOI: https://doi.org/10.1021/acsanm.2c03406 Publication Date: October 6, 2022 © 2022 The Authors. Published by American Chemical Society

This paper appears to be open access.

3D print healthy chocolates

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I’m a little late for Valentine’s Day, February 14, 2023, but it’s not too late for chocolate.

A February 14, 2023 news item on ScienceDaily describes research into 3D printing ‘healthy’ chocolates,

A Rutgers [Rutgers State University of New Jersey, US] scientist has developed a formulation of low-fat chocolate that can be printed on a 3D printer in pretty much any shape a person can conceive, including a heart.

…

A February 13, 2023 Rutgers University news release (also on EurekAlert but published February 14, 2023) by Kitta MacPherson, which originated the news item, describes research into ‘functional foods’,

The work heralds what the researcher hopes will be a new line of “functional foods” – edibles specially designed with health benefits. The aim is to develop healthier kinds of chocolate easily accessible to consumers.

Reporting in the scientific journal, Food Hydrocolloids, a Rutgers-led team of scientists described the successful creation and printing of a mixture producing low-fat chocolate — substituting fatty cocoa butter with a lower-fat, water-in-oil emulsion.

“Everybody likes to eat chocolate, but we are also concerned with our health,” said Qingrong Huang, a professor in the Department of Food Science at the Rutgers School of Environmental and Biological Sciences. “To address this, we have created a chocolate that is not only low-fat, but that can also be printed with a 3D printer. It’s our first ‘functional’ chocolate.”

Huang, an author of the study, said he already is working on manipulating sugar content in the new chocolate formulation for low-sugar and sugar-free varieties.

Researchers create emulsions by breaking down two immiscible liquids into minute droplets. In emulsions, the two liquids will usually quickly separate – as is the case with oil and vinegar – unless they are held together by a third, stabilizing ingredient known as an emulsifier. (An egg is the emulsifier in a vinaigrette.)

Chocolate candy is generally made with cocoa butter, cocoa powder and powdered sugar and combined with any one of a variety of different emulsifiers.

For the study, the scientific team experimented with different ratios of the ingredients for a standard chocolate recipe to find the best balance between liquid and solid for 3D printing. Seeking to lower the level of fat in the mixture, researchers created a water-in-cocoa butter emulsion held together by gum arabic, an extract from the acacia tree that is commonly used in the food industry, to replace the cocoa butter. The researchers mixed the emulsion with golden syrup to enhance the flavor and added that combination to the other ingredients.

As delightful as it is to eat, Huang said, chocolate is a material rich with aspects for food scientists to explore.

Employing advanced techniques examining the molecular structure and physical properties of chocolate, researchers investigated the printed chocolate’s physical characteristics. They were seeking the proper level of viscosity for printing and looking for the optimal texture and smoothness “for a good mouthfeel,” Huang said. Experimenting with many different water-oil ratios, they varied the percentages of all the main ingredients before settling on one mixture.

In 3D printing, a printer is used to create a physical object from a digital model by laying down layers of material in quick succession. The 3D printer, and the shapes it produces, can be programmed by an app on a cellphone, Huang said.

Ultimately, Huang said he plans to design functional foods containing healthy added ingredients – substances he has spent more than two decades studying, such as extracts from orange peel, tea, red pepper, onion, Rosemary, turmeric, blueberry and ginger – that consumers can print and eat.

“3D food printing technology enables the development of customized edible products with tailored taste, shape and texture as well as optimal nutrition based on consumer needs,” Huang said.

Other researchers on the study included Siqi You and Xuanxuan Lu of the Department of Food Science and Engineering at Jinan University in Guangzhou, China.

Here’s a link to and a citation for the paper,

Development of fat-reduced 3D printed chocolate by substituting cocoa butter with water-in-oil emulsions by Siqi You, Qingrong Huang, and Xuanxuan Lu. Food Hydrocolloids Volume 135, February 2023, 108114 DOI: https://doi.org/10.1016/j.foodhyd.2022.108114

This paper is behind a paywall.

In Brazil: Applications open for July 3 – 15, 2023 School of Advanced Science on Nanotechnology, Agriculture and Environment

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According to the December 15, 2022 Fundação de Amparo à Pesquisa do Estado de São Paulo press release on EurekAlert applications will be received until February 5, 2023,

The São Paulo School of Advanced Science on Nanotechnology, Agriculture and Environment (SPSAS NanoAgri&Enviro) will be held on July 3-15 at the Brazilian Center for Research in Energy and Materials (CNPEM) in Campinas, São Paulo state, Brazil. 

Reporters are invited to reach the organizing committee through the email eventos@cnpem.br, for opportunities to visit the school and sessions.

Designed to meet an increasing level of content depth and complexity, the SPSAS NanoAgri&Enviro will cover the following topics: i) Nanotechnology, innovation, and sustainability; ii) Synthesis, functionalization, and characterization of nanomaterials; iii) Characterization of nanoparticles in complex matrices; iv) Synchrotron Light for nano-agri-environmental research; v) Biological and environmental applications of nanoparticles; vi) Nanofertilizers and Nanoagrochemicals; vii) Ecotoxicology, geochemistry and nanobiointerfaces; viii) Nanosafety and Nanoinformatics; ix) International harmonization and regulatory issues; x) Environmental implications of nanotechnology.

Discussions regarding those topics will benefit from the participation of internationally renowned scientists as speakers, including Mark V. Wiesner (Duke University), Iseult Lynch (University of Birmingham), Leonardo F. Fraceto (São Paulo State University – UNESP), Gregory V. Lowry (Carnegie Mellon University), Marisa N. Fernandes (Federal University of São Carlos – UFSCar), Caue Ribeiro (Brazilian Agricultural Research Corporation – EMBRAPA), and others.

The program also comprise didactic activities programmed among theoretical interactive classes, practical experiments (hands-on), and technical visits to world-class facilities and specialized laboratories from several institutions in São Paulo state.

The São Paulo Research Foundation (FAPESP) is supporting the event through its São Paulo School of Advanced Science Program (SPSAS http://espca.fapesp.br/home). Undergraduate students, postdoctoral fellows and researchers who are already working on subjects relating to the school can apply to receive financial support to cover the cost of air travel, accommodation and meals. Applications must be submitted by February 5, 2023.

More information: https://pages.cnpem.br/spsasnano/.

I looked up the criteria for eligible applicants and found this among the other criteria (from the Applications page),

Participating students must be enrolled in undergraduate or graduate courses in Brazil or abroad, being potential candidates for Master’s, Doctoral or Post-Doctoral internships in higher education and research institutions in the state of São Paulo. Doctors may also be accepted. [emphases mine]

If I read that correctly, it means that people who are considering or planning to further their studies in the state of São Paulo are being invited to apply.

I recognized two of the speakers’ names, Mark Wiesner and Iseult Lynch both of whom have been mentioned here a number of times as has Gregory V. Lowry. (Wiesner very kindly helped with an art/sci project I was involved with [Steep] a number of years ago.)

Good luck with your application!

Clay film keeps your apples fresh

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Which apple would you like to eat?

Caption: Extent of decay in apples treated with clay film and cling wrap. Credit: Miharu Eguchi National Institute for Materials Science eguchi.miharu@nims.go.jp

This research into food packaging comes from Japan’s National Institute for Materials in a March 8, 2022 press release (also on EurekAlert but published on April 12, 2022),

An international research team consisting of NIMS, The University of Queensland and National Taiwan University has succeeded in creating a clay film with its gas permeability optimized for long-term storage of fresh produce by adjusting the sizes of the clay nanosheet particles comprising it. The team then uniformly coated the surfaces of various fruits with the film. This treatment kept the fruits’ respiration rates low without completely depriving them of oxygen, preventing them from decaying.

Efforts have been made to develop gas barrier films using clay nanosheets. Although some researchers attempted to improve the film properties of clay nanosheets by adding organic polymers to them, films can also be formed using only clay nanosheets without additives. Only a few studies had previously evaluated the physical properties of clay films composed solely of clay nanosheets.

This international joint research team focused on the gas permeability of clay films and found that a film composed of clay nanosheets with particle sizes in the range of several dozen nanometers (1 nm = one millionth of 1 mm) had relatively high permeability to gas molecules as they can pass through gaps between particles. This gas permeability is equivalent to that of plastic bags with minute pores used to store fresh produce. These bags are able to adequately reduce oxygen supply to fresh fruit, preventing it from ripening too rapidly. The gas permeability similarities between the clay film and the plastic bags inspired the research team to assess the ability of the clay film to preserve the quality of fresh produce for long periods of time.

In this research, the team applied a suspension of clay nanosheets to the surfaces of various fruits (e.g., apples, bananas and oranges) to form uniform films on their surfaces. The team also prepared untreated fruits and fruits covered in cling wrap for comparison. The gas emissions and appearance of these treated and untreated fruits were monitored for several months. As shown in the figure [above], the untreated apples (the first photo from the left) had decayed by the end of the experimental period and the apples covered only in cling wrap (the fourth photo from the left) had also decayed and grown mold. By contrast, the apples coated with the clay film (the two middle photos) did not decay or grew mold, presumably because the film reduced the external oxygen supply needed for ripening and mold growth. In addition, the clay film was confirmed to be in tight contact with the surfaces of the apples it coated, suggesting that it may be able to effectively block the diffusion of ethylene into the air, a phytohormone which plays an important role in inducing fruit ripening.

In addition to its potential ability to restrict the external oxygen supply and ethylene diffusion, the clay film may be able to prevent odor compounds produced by fresh produce from diffusing into the air, possibly making them less attractive to pests. In future research, the team plans to improve the ease of application and strength of the clay film to make it more suitable for preserving the quality of fresh produce during its transportation to the market.

This project was carried out by an international joint research team consisting of Miharu Eguchi (Senior Researcher, Mesoscale Materials Chemistry Group, International Center for Materials Nanoarchitectonics, NIMS) and researchers from The University of Queensland and National Taiwan University. This work was supported in part by  JST-ERATO Yamauchi Materials Space-Tectonics Project.

Here’s a link to and a citation for the paper,

Highly adhesive and disposable inorganic barrier films: made from 2D silicate nanosheets and water by Miharu Eguchi, Muxina Konarova, Nagy L. Torad, Te-An Chang, Dun-Yen Kang, Joe Shapter and Yusuke Yamauchi. J. Mater. Chem. A, 2022,10, 1956-1964 DOI: https://doi.org/10.1039/D1TA08837H First published 02 Dec 2021 Print version published January 28, 2022

This paper is behind a paywall.

Say goodbye to crunchy (ice crystal-laden) in ice cream thanks to cellulose nanocrystals (CNC)

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The American Chemical Society (ACS) held its 2022 Spring Meeting from March 20 – 24, 2022 and it seems like a good excuse to feature ice cream.

Adding cellulose nanocrystals prevents the growth of small ice crystals (bottom left) into the large ones (top left) that can make ice cream (right) unpleasantly crunchy. Scale bar = 100 μm. Credit: Tao Wu

A March 20, 2022 news item on phys.org introduces an ice cream presentation given at the meeting on Monday, March 20, 2022,

Ice cream can be a culinary delight, except when it gets unpleasantly crunchy because ice crystals have grown in it. Today, scientists report that a form of cellulose obtained from plants can be added to the tasty treat to stop crystals cold—and the additive works better than currently used ice growth inhibitors in the face of temperature fluctuations. The findings could be extended to the preservation of other frozen foods and perhaps donated organs and tissues

…

A March 20, 2022 ACS press release, which originated the news item, provides more details about crunchy ice cream and how it might be avoided,

Freshly made ice cream contains tiny ice crystals. But during storage and transport, the ice melts and regrows. During this recrystallization process, smaller crystals melt, and the water diffuses to join larger ones, causing them to grow, says Tao Wu, Ph.D., the project’s principal investigator. If the ice crystals become bigger than 50 micrometers — or roughly the diameter of a hair — the dessert takes on a grainy, icy texture that reduces consumer appeal, Wu says. “Controlling the formation and growth of ice crystals is thus the key to obtaining high-quality frozen foods.”

One fix would be to copy nature’s solution: “Some fish, insects and plants can survive in sub-zero temperatures because they produce antifreeze proteins that fight the growth of ice crystals,” Wu says. But antifreeze proteins are costlier than gold and limited in supply, so they’re not practical to add to ice cream. Polysaccharides such as guar gum or locust bean gum are used instead. “But these stabilizers are not very effective,” Wu notes. “Their performance is influenced by many factors, including storage temperature and time, and the composition and concentration of other ingredients. This means they sometimes work in one product but not in another.” In addition, their mechanism of action is uncertain. Wu wanted to clarify how they work and develop better alternatives.

Although Wu didn’t use antifreeze proteins in the study, he drew inspiration from them. These proteins are amphiphilic, meaning they have a hydrophilic surface with an affinity for water, as well as a hydrophobic surface that repels water. Wu knew that nano-sized crystals of cellulose are also amphiphilic, so he figured it was worth checking if they could stop ice crystal growth in ice cream. These cellulose nanocrystals (CNCs) are extracted from the plant cell walls of agricultural and forestry byproducts, so they are inexpensive, abundant and renewable.

In a model ice cream — a 25% sucrose solution — the CNCs initially had no effect, says Min Li, a graduate student in Wu’s lab at the University of Tennessee. Though still small, ice crystals were the same size whether CNCs were present or not. But after the model ice cream was stored for a few hours, the researchers found that the CNCs completely shut down the growth of ice crystals, while the crystals continued to enlarge in the untreated model ice cream.

The team’s tests also revealed that the cellulose inhibits ice recrystallization through surface adsorption. CNCs, like antifreeze proteins, appear to stick to the surfaces of ice crystals, preventing them from drawing together and fusing. “This completely contradicted the existing belief that stabilizers inhibit ice recrystallization by increasing viscosity, which was thought to slow diffusion of water molecules,” adds Li, who will present the work at the meeting.

In their latest study, the scientists found that CNCs are more protective than current stabilizers when ice cream is exposed to fluctuating temperatures, such as when the treat is stored in the supermarket and then taken home. The team also discovered the additive can slow the melting of ice crystals, so it could be used to produce slow-melting ice cream. Other labs have shown the stabilizer is nontoxic at the levels needed in food, Wu notes, but the additive would require review by the U.S. Food and Drug Administration.

With further research, CNCs could be used to protect the quality of other foods — such as frozen dough and fish — or perhaps to preserve cells, tissues and organs in biomedicine, Wu says. “At present, a heart must be transplanted within a few hours after being removed from a donor,” he explains. “But this time limit could be eliminated if we could inhibit the growth of ice crystals when the heart is kept at low temperatures.”

…

Interesting to see that this research into ice cream crystals could lead to new techniques for organ transplants.

Cellulose nanocrystals (CNC), protein, and starch eletrospun to develop ‘smart’ food packaging

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A December 29, 2021 news item on ScienceDaily announces research into ;smart’ sustainable packaging from a joint Nanyang Technical University and Harvard University,

A team of scientists from Nanyang Technological University, Singapore (NTU Singapore) and Harvard T.H. Chan School of Public Health, US, has developed a ‘smart’ food packaging material that is biodegradable, sustainable and kills microbes that are harmful to humans. It could also extend the shelf-life of fresh fruit by two to three days.

The waterproof food packaging is made from a type of corn protein called zein, starch and other naturally derived biopolymers, infused with a cocktail of natural antimicrobial compounds. These include oil from thyme, a common herb used in cooking, and citric acid, which is commonly found in citrus fruits.

…

A December 28, 2021 Nanyang Technological University press release (PDF), also on EurekAlert but published December 27, 2021, which originated the news item, offers a few more details about the research (Note 1: Links have been removed; Note 2: I had to dig into the abstract to find the cellulose nanocrystals),

In lab experiments, when exposed to an increase in humidity or enzymes from harmful bacteria, the fibres in the packaging have been shown to release the natural antimicrobial compounds, killing common dangerous bacteria that contaminate food, such as E. Coli and Listeria, as well as fungi.

The packaging is designed to release the necessary miniscule amounts of antimicrobial compounds only in response to the presence of additional humidity or bacteria. This ensures that the packaging can endure several exposures, and last for months.

As the compounds combat any bacteria that grow on the surface of the packaging as well as on the food product itself, it has the potential to be used for a large variety of products, including ready-to-eat foods, raw meat, fruits, and vegetables.

In an experiment, strawberries that were wrapped in the packaging stayed fresh for seven days before developing mould, compared to counterparts that were kept in mainstream fruit plastic boxes, which only stayed fresh for four days.

The invention is the result of the collaboration by scientists from the NTU-Harvard T. H. Chan School of Public Health Initiative for Sustainable Nanotechnology (NTU-Harvard SusNano), which brings together NTU and Harvard Chan School researchers to work on cutting edge applications in agriculture and food, with an emphasis on developing non-toxic and environmentally safe nanomaterials.

The development of this advanced food packaging material is part of the University’s efforts to promote sustainable food tech solutions, that is aligned with the NTU 2025 strategic plan, which aims to develop sustainable solutions to address some of humanity’s pressing grand challenges.

Professor Mary Chan, Director of NTU’s Centre of Antimicrobial Bioengineering, who co-led the project, said: “This invention would serve as a better option for packaging in the food industry, as it has demonstrated superior antimicrobial qualities in combatting a myriad of food-related bacteria and fungi that could be harmful to humans. The packaging can be applied to various produces such as fish, meat, vegetables, and fruits. The smart release of antimicrobials only when bacteria or high humidity is present, provides protection only when needed thus minimising the use of chemicals and preserving the natural composition of foods packaged.”

Professor Philip Demokritou, Adjunct Professor of Environmental Health at Harvard Chan School, who is also Director of Nanotechnology and Nanotoxicology Center and Co-director of NTU-Harvard Initiative on Sustainable Nanotechnology, who co-led the study, said: “Food safety and waste have become a major societal challenge of our times with immense public health and economic impact which compromises food security. One of the most efficient ways to enhance food safety and reduce spoilage and waste is to develop efficient biodegradable non-toxic food packaging materials. In this study, we used nature-derived compounds including biopolymers, non-toxic solvents, and nature-inspired antimicrobials and develop scalable systems to synthesise smart antimicrobial materials which can be used not only to enhance food safety and quality but also to eliminate the harm to the environment and health and reduce the use of non-biodegradable plastics at global level and promote sustainable agri-food systems.” 

Providing an independent assessment of the work done by the NTU research team, Mr Peter Barber, CEO of ComCrop, a Singapore company that pioneered urban rooftop farming, said: “The NTU-Harvard Chan School food packaging material would serve as a sustainable solution for companies like us who want to cut down on the usage of plastic and embrace greener alternatives. As ComCrop looks to ramp up product to boost Singapore’s food production capabilities, the volume of packaging we need will increase in sync, and switching to a material such as this would help us have double the impact. The wrapping’s antimicrobial properties, which could potentially extend the shelf life of our vegetables, would serve us well. The packaging material holds promise to the industry, and we look forward to learning more about the wrapping and possibly adopting it for our usage someday.”

The results of the study were published in the peer-reviewed academic journal ACS Applied Materials & Interfacesin October [2021].

Cutting down on packaging waste

The packaging industry is the largest and growing consumer of synthetic plastics derived from fossil fuels, with food packaging plastics accounting for the bulk of plastic waste that are polluting the environment.

In Singapore, packaging is a major source of trash, with data from Singapore’s National Environment Agency showing that out of the 1.76 million tonnes of waste disposed of by domestic sources in 2018, one third of it was packaging waste, and over half of it (55 per cent) was plastic.

The smart food package material, when scaled up, could serve as an alternative to cut down on the amount of plastic waste, as it is biodegradable. Its main ingredient, zein, is also produced from corn gluten meal, which is a waste by-product from using corn starch or oils in order to produce ethanol.

The food packaging material is produced by electrospinning[1] the zein, the antimicrobial compounds with cellulose, a natural polymer starch that makes up plant cell walls, and acetic acid, which is commonly found in vinegar.

Prof Mary Chan added: “The sustainable and biodegradable active food packaging, which has inbuilt technology to keep bacteria and fungus at bay, is of great importance to the food industry. It could serve as an environmentally friendly alternative to petroleum-based polymers used in commercial food packaging, such as plastic, which have a significant negative environmental impact.”

Prof Demokritou added: “Due to the globalisation of food supply and attitude shift towards a healthier lifestyle and environmentally friendly food packaging, there is a need to develop biodegradable, non-toxic and smart/responsive materials to enhance food safety and quality. Development of scalable synthesis platforms for developing food packaging materials that are composed of nature derived, biodegradable biopolymers and nature inspired antimicrobials, coupled with stimuli triggered approaches will meet the emerging societal needs to reduce food waste and enhance food safety and quality.”

The team of NTU and Harvard Chan School researchers hope to scale up their technology with an industrial partner, with the aim of commercialisation within the next few years.

They are also currently working on developing other technologies to develop biopolymer-based smart food package materials to enhance food safety and quality.

Here’s a link to and a citation for the paper, followed by the key (nanocellulose crystal mention) sentences in the abstract,

Enzyme- and Relative Humidity-Responsive Antimicrobial Fibers for Active Food Packaging by Zeynep Aytac, Jie Xu, Suresh Kumar Raman Pillai, Brian D. Eitzer, Tao Xu, Nachiket Vaze, Kee Woei Ng, Jason C. White, Mary B. Chan-Park, Yaguang Luo, and Philip Demokritou. ACS Appl. Mater. Interfaces 2021, 13, 42, 50298–50308 I: https://doi.org/10.1021/acsami.1c12319 Publication Date: October 14, 2021 Copyright © 2021 American Chemical Society

This paper is behind a paywall.

Excerpt from abstract,

Active food packaging materials that are sustainable, biodegradable, and capable of precise delivery of antimicrobial active ingredients (AIs) are in high demand. Here, we report the development of novel enzyme- and relative humidity (RH)-responsive antimicrobial fibers with an average diameter of 225 ± 50 nm, which can be deposited as a functional layer for packaging materials. Cellulose nanocrystals (CNCs) [emphasis mine], zein (protein), and starch were electrospun to form multistimuli-responsive fibers that incorporated a cocktail of both free nature-derived antimicrobials such as thyme oil, citric acid, and nisin and cyclodextrin-inclusion complexes (CD-ICs) of thyme oil, sorbic acid, and nisin. …

I have been following the CNC story for some time. If you’re curious, just use ‘cellulose nanocrystal(s)’ as your search term. You can find out more about ComCrop here.