A mixture of trees purifies urban air best

Peer-Reviewed Publication

UNIVERSITY OF GOTHENBURG

 

IMAGE: MEASUREMENT OF CHLOROPHYLL IN LEAVES USING A CHLOROPHYLL MEASUREMENT DEVICE CALLED A SPAD. THE MEASUREMENT IS DONE USING LIGHT, LEAVING THE LEAF UNDAMAGED. view more 

CREDIT: JENNY KLINGBERG

Conifers are generally better than broadleaved trees at purifying air from pollutants. But deciduous tree may be better at capturing particle-bound pollution. A new study led by the University of Gothenburg shows that the best trees for air purification depend on the type of pollutant involved.

Trees and other greenery in cities provide many benefits that are important for the well-being of residents. Leaves and needles on trees filter air pollutants and reduce exposure to hazardous substances in the air. But which trees purify the air most effectively? Researchers from the University of Gothenburg have collected leaves and needles from eleven different trees growing in the same place in the Gothenburg Botanical Garden’s arboretum (tree collection) to analyse which substances they have captured.

“This tree collection provides a unique opportunity to test many different tree-species with similar environmental conditions and exposure to air pollutants,” says Jenny Klingberg, a researcher at the Gothenburg Botanical Garden.

Harmful pollutants

A total of 32 different pollutants were analysed, some of which are bound to particles of various sizes. Others are gaseous. There is a proven connection between exposure to air pollutants and increased risk of cardiovascular diseases and airway problems. This project has focused on polycyclic aromatic hydrocarbons (PAHs). In cities, traffic is the biggest source of these pollutants, which are released due to incomplete combustion in engines.

“Our analyses show that different tree species have different abilities to absorb air pollutants. Conifers generally absorbed more gaseous PAHs than broadleaved trees. Another advantage of conifers is that they also act as air purifiers in winter, when air pollution is usually at its highest,” says Jenny Klingberg.

Needles clean air for many years

The researchers also saw that needles continued to absorb air pollutants for several years, which leaves cannot do for obvious reasons. But broadleaved trees had other advantages. They were more efficient at cleaning the air of particles, which is thought to be due to the leaves having a larger surface area to which particles can attach.

“The various species differed more than we expected. Larch, which is a conifer that sheds its needles each autumn, was best in test. Larch trees absorbed the most particle-bound pollutants, but were also good at capturing gaseous PAHs,” says Jenny Klingberg.

Needles and leaves do not, however, break down pollutants to any greater extent, even if sunlight can start that process. Thus there is a risk that the soil beneath the trees will be contaminated by pollutants when the leaves and needles shed and decompose. This places the ecosystem in the soil at risk of being affected, though this has not been investigated in the current study being published in the journal Ecological Indicators.

“The pollutants do not appear to impact the trees’ photosynthesis; leaf chlorophyll content is just as high in the most polluted areas of Gothenburg compared with trees that grow in less polluted environments. But this likely looks different in cities with even worse air quality,” says project leader Håkan Pleijel, professor of applied environmental science at the University of Gothenburg.

Careful urban planning is needed

However, you should not simply start filling city streets with trees to improve air quality for residents. Several factors determine the benefit. An alley of trees in a narrow street canyon can reduce air flow, negatively affecting dispersion and dilution of the air pollutants and therefore increase concentrations of contaminants locally on busy streets. This means that on narrow streets sheltered from wind, lower-growing vegetation, like hedges, may be preferable. Careful urban planning is necessary, combining different tree species to optimise air purification and to take into account other functions and benefits of trees, according to the researchers.

“This study contributes to improving our understanding of the ability of trees to clean the air and which species are best at absorbing air pollutants,” says Håkan Pleijel. This knowledge is important for urban planning when designing sustainable cities. While trees and greenery can contribute to better air quality in cities, at the end of the day the most important measure is to reduce emissions.

Uptake of hydrocarbon in different tree-species

CREDIT

Håkan Pleijel

JOURNAL

Ecological Indicators

DOI

10.1016/j.ecolind.2022.109681 

METHOD OF RESEARCH

Content analysis

ARTICLE TITLE

Differences in accumulation of polycyclic aromatic compounds (PACs) among eleven broadleaved and conifer tree species

Community strategy reduced opioid overdose deaths in Pennsylvania counties

Peer-Reviewed Publication

UNIVERSITY OF PITTSBURGH

 

IMAGE: JANICE PRINGLE, PH.D., PROFESSOR OF PHARMACY AND THERAPEUTICS AND DIRECTOR OF THE PROGRAM EVALUATION AND RESEARCH UNIT (PERU) AT THE UNIVERSITY OF PITTSBURGH SCHOOL OF PHARMACY. view more 

CREDIT: JAN SHAW, UNIVERSITY OF PITTSBURGH

PITTSBURGH, March 6, 2023 — The monthly opioid overdose death (ODD) rate fell by 30% in Pennsylvania counties that implemented a novel community-focused strategy developed by University of Pittsburgh researchers, according to a new study published today in the Journal of Studies on Alcohol and Drugs.

By analyzing counties that did or didn’t implement the Pennsylvania Opioid Overdose Reduction Technical Assistance Center (ORTAC) strategy over time, the researchers estimate that this cost-effective, community-led approach prevented 1,818 opioid-related deaths over two years.

“I passionately believe that communities have to come together and be empowered to take control of their own public health to really make sea change on issues like ODD,” said senior author Janice Pringle, Ph.D., professor of pharmacy and therapeutics and director of the Program Evaluation and Research Unit (PERU) at the Pitt School of Pharmacy. “Our study is one of the first to show that a community approach is how you move the needle on preventing ODD.”

According to Pringle, public health issues such as the opioid crisis are usually tackled through dozens of disconnected initiatives led by organizations or systems that target specific populations. But this kind of approach can lead to certain groups of people falling through the cracks and perpetuating disparities in who is accessing care.

“ORTAC aims to bring efforts together, pool resources and integrate services to reduce opioid-related overdose deaths at a community level,” said Pringle. “If the opioid crisis is a tree, one thousand steak knives is not going to chop it down. We need sixty-seven hands — one for each county in Pennsylvania — on the chainsaw.”

Pringle and her team developed a systematic eight-step framework to build and support community coalitions and help them plan, implement and sustain efforts to decrease opioid supply and demand and reduce the risk of opioid overdose in their counties.

The first step involves gathering leadership from multiple sectors — including first responders, emergency departments, the drug and alcohol system, the mental health system and criminal justice — who have a shared goal of addressing the opioid crisis.

“The idea behind ORTAC is that community members and people on the front lines know what’s best for their community,” said lead author Renee Cloutier, Ph.D., research scientist in the Pitt School of Pharmacy’s Department of Pharmacy and Therapeutics and scientific director of PERU. “The ORTAC team worked to develop and activate community coalitions to clarify the problems in their community, generate plans and act on them.”

After assessing local data to understand overdose deaths and identify their community’s unique needs, coalitions developed and enacted a strategic plan to reduce opioid deaths. Interventions included improving access to treatment programs, educating first responders in leave-behind practices for the opioid-reversing drug naloxone, implementing harm reduction strategies such as syringe service programs and drug disposal services, and developing messaging campaigns aimed at reducing stigma.

To understand the impact of ORTAC, the researchers used data from OverdoseFreePA to analyze ODDs from 2016 to 2019 in 29 counties where ORTAC was implemented and 19 comparison counties. While 67% of ORTAC counties had a reduction in ODD per 100,000 people, just 47% of the comparison counties had a reduction over the same period.

After accounting for factors that could affect opioid deaths, such as county distribution of naloxone beyond ORTAC efforts, illicit drug supply and opioid prescriptions, the researchers found that the ODD rate in ORTAC counties was consistently lower than comparison counties over time, a difference ranging from 1.5 to 3.8 deaths per 100,000 people in the first two years following ORTAC implementation.

“If you fund communities and provide structured support, you can make transformational change beyond what might be possible with a top-down approach,” said Cloutier. “We hope to see more funding targeted toward supporting communities on the ground in this way.”

The researchers calculated that it cost less than $6,000 to prevent each overdose death. For comparison, another analysis estimated the savings associated with avoiding a single ODD at $10.5 million.

“Our strategy had a meaningful impact on reducing ODD and is incredibly cost-effective,” said Pringle. “With more funding and support, we can continue to guide communities to reduce the risk of ODD for everyone because this issue is in all our backyards. The opioid crisis affects us all, and there is so much more work to be done.”

Other authors of the study were Arnie Aldridge, Ph.D., and William Dowd, B.A., both of RTI International; and Glenn Hoffman, B.A., B.S., Kristina L. Boyd, M.S., Erh-Hsuan Wang, Ph.D., Kiandra Foster, M.S., and Karley Snyder, M.S., all of Pitt.

This study was funded by the Pennsylvania Commission on Crime and Delinquency.

##

---

JOURNAL

Journal of Studies on Alcohol and Drugs

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Pennsylvania's Community Coordination Strategy to Reduce Opioid Overdose Deaths

ARTICLE PUBLICATION DATE

6-Mar-2023

Physician workforce planning must adjust for aging population, changing practice patterns: New analysis

Peer-Reviewed Publication

CANADIAN MEDICAL ASSOCIATION JOURNAL

Why are Canadians having problems accessing physicians despite historic highs in physician numbers? Factoring in changing demographics and physician work trends can help with physician workforce planning, according to a new analysis in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.221239.

"[T]he increasing [health care] needs of an aging population have been empirically important since around 2005, while the supply of physician service hours has simultaneously declined in a manner that is largely unrelated to the evolving age–sex composition of the physician workforce," writes Dr. Arthur Sweetman, Department of Economics, McMaster University, Hamilton, Ontario, with coauthors. "Thus, relying on simple trends in physicians-per-capita ratios for workforce planning is misleading and not helpful."

The authors hope their analysis will inform governments and the medical profession in planning the appropriate number of new physicians who should enter medical practice.

The analysis looked at trends in the number of physicians and hours of work, and factored in the needs of an aging population between 1987 and 2020. Physician hours of work, while being higher than in most other occupations, declined by 20.6%, from an average of 54.3 hours per week in 1987 to 43.1 hours per week in 2020.

"Despite working more than other occupations, physicians have faced mounting challenges meeting patient needs," says coauthor Dr. Boris Kralj, a professor of economics at McMaster University. "The 1980s physician workload proved unsustainable. In 1987, the average physician worked almost 13 and a half hours per week more than the average Canadian worker, whereas in 2020 that gap had declined to about 6.2 additional hours per week."

Simple adjustments for population aging and physicians' declining hours of work change the apparent 35% increase in physicians per capita between 1987 and 2019 into a 4% reduction.

"The current physician practice environment is not one of resource abundance as suggested by high physician counts, but rather a period of physician shortages like that in the late 1990s. In fact, we are below levels observed in 1987," says Dr. Kralj. "The majority of the increase in physician supply over the past 3 decades has been offset by the rising needs of an aging population."

The analysis also debunks the theory that larger numbers of physicians who identify as working fewer average hours is a substantial contributor to the shortages.

"Females had lower average hours, but that average was relatively stable from 1987 to 2020," write the authors. "In contrast, the hours of male physicians declined, and the gender gap in hours diminished across the period."      

They suggest several potential reasons for the decline in working hours beyond the modest contribution from a larger proportion of older and female physicians in the workforce. Other often-discussed issues, such as physician burnout combined with a desire for an improved work–nonwork balance, must also be at play.

"Our analysis shows that measures of physicians per capita need to be complemented with both demand- and supply-side adjustments to inform planning for health human resources in medicine."

The authors suggest caution in interpreting 2020 numbers as that was the start of the COVID-19 pandemic, and they were unable to evaluate trends for the later part of the pandemic owing to data limitations.
 

---

JOURNAL

Canadian Medical Association Journal

DOI

10.1503/cmaj.221239 

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Physician workforce planning in Canada: the importance of accounting for population aging and changing physician hours of work

ARTICLE PUBLICATION DATE

6-Mar-2023

Scientists suggest guidelines to prevent SARS-CoV-2 transmission from deceased individuals

Peer-Reviewed Publication

THE INSTITUTE OF MEDICAL SCIENCE, THE UNIVERSITY OF TOKYO

 

IMAGE: SARS-COV-2-INFECTED DEAD HAMSTERS HAD HIGH VIRUS TITERS. ANGEL CARE OR EMBALMING COULD PREVENT TRANSMISSION FROM INFECTED HAMSTERS' DEAD BODIES. PROPER TREATMENT OF SARS-COV-2-INFECTED CORPSES IS CRITICAL TO PREVENT THE SPREAD OF COVID-19 INFECTION. view more 

CREDIT: YOSHIHIRO KAWAOKA FROM UNIVERSITY OF TOKYO, JAPAN.

Their findings highlight that embalming or "angel care" can effectively prevent virus transmission, to allow family members to say goodbye

During the pandemic, COVID-19 control measures in several countries prevented family members from coming into contact with loved ones who died from the infection. This had an impact on cremation practices and caused emotional distress. Researchers from Japan have now shown that, while deceased SARS-CoV-2-infected individuals may be a potential source of the virus, transmission can be stopped by using appropriate procedures. Their research provides evidence for national guidelines.

The coronavirus disease 2019 (COVID-19) pandemic has presented unique challenges for clinicians, patients, and families. Of these, the death and loss of a loved one has been the one of the most painful and overwhelming. This psychological stress is compounded by the inability to see loved ones one last time and perform cremation rituals, due to the restrictions around exposure to the bodies of patients who died as a result of COVID-19. Many medical facilities still refuse to allow bereaved family members to perform cremation for those who died from the infection. However, there is a lack of evidence to support these restrictions, and their acceptability varies between countries.

There have been reports of infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) being found in individuals who died from the infection. However, it is unclear whether the virus can be transmitted from their bodies. In Japan, nurses perform postmortem care or "angel care" for deceased persons by wiping their surfaces and shaving or applying chemicals. In addition, the body openings are plugged with cotton pads to prevent bodily fluid leakage. In contrast, “embalming” or the treatment of a body to keep it from decaying, is common in the United States and Canada, and has recently become popular in Japan. How these practices impact the risk of infection from deceased persons, particularly for infection with SARS-CoV-2, is unknown.

To fill this knowledge gap, a research team from Japan has analyzed the possibility of SARS-CoV-2 transmission from a deceased individual's body by using a hamster model. They analyzed whether the virus can spread from COVID-19-infected dead hamsters, and whether this spread can be reduced by using angel care and embalming. Their recent work was published in mSphere on 10 January 2023. Sharing the motivation behind their investigation, Prof. Kawaoka states, “It has been two and a half years since the COVID-19 pandemic began, and the transmissibility of SARS-CoV-2 from the body of a deceased, infected person still remains unclear.”

The researchers infected Syrian hamsters with SARS-CoV-2/UT-NCGM02/human/2020 (the Wuhan strain of the virus) before euthanizing them and treating the bodies with either angel care or embalming (7% formaldehyde and 4% glutaraldehyde) treatment. As a control, one group of hamster bodies was treated with alcohol and wrapped in wire nets. Healthy hamsters were then co-housed with the bodies for 24 hours and their organs were collected to check for transmission of the virus.

high SARS-CoV-2 titers were found in the lungs and nasal turbinate of some hamsters who shared a house with a dead infected hamster, implying a risk of infection. In contrast, angel care was effective in preventing the leakage of gas and bodily fluid leakage from the bodies, effectively preventing infection of the co-housed hamsters. Embalming also prevented the transmission of virus to any of the live hamsters. Prof. Kawaoka explains, “Infectious viruses may be transmitted via postmortem gases produced during the decomposition process or other postmortem changes in the dead body. Angel care or embalming could prevent this transmission.”

In summary, these findings emphasize the importance of avoiding infection when handling the body of a deceased individual who had SARS-CoV-2 infection, and that sealing body cavities can control virus spread even if embalming is not performed. Prof. Kawaoka concludes by saying, "We do know that the virus remains in the bodies of deceased persons, but with appropriate precautions and guidelines, we can at least let the families see their loved ones once before they depart."

These findings could guide local and national guidelines on funerary rites and provide a modicum of solace to those who lose loved ones to COVID-19.

High virus titers were found in SARS-CoV-2-infected dead hamsters. Angel care or embalming could prevent transmission from dead bodies of infected hamsters. This suggests that preventing infection is critical when handling infected corpses, as is the proper treatment of SARS-CoV-2-infected corpses.

CREDIT

Yoshihiro Kawaoka from University of Tokyo, Japan.

---

JOURNAL

mSphere

DOI

10.1128/msphere.00411-22 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

SARS-CoV-2 Transmission from Virus-Infected Dead Hamsters

ARTICLE PUBLICATION DATE

10-Jan-2023

COI STATEMENT

Kenichiro Hashizume and Kazuho Ushiwata are employed by GSI Co., LTD. The other authors declare no competing financial interests.

Do you see me? New study examines how women of colour experience invisibility in the workplace

Peer-Reviewed Publication

UNIVERSITY OF WESTERN ONTARIO, IVEY BUSINESS SCHOOL

“As a Black woman, I’m invisible. They just erase your humanity. You don’t exist in front of them.” (Tessa, 33-year-old Black research assistant)

“It wasn’t about disliking what I did or being judgmental of what I did. It was a different kind of problem, to not be acknowledged. They didn’t care. There was no curiosity. They didn’t give a f***. We were invisible.” (Brinda, 30-year-old South Asian consultant)

Invisibility is a salient and recurring experience of mistreatment for women of colour working in traditionally white and male professions, two researchers found in their recent landmark study. Barnini Bhattacharyya of the Ivey Business School at Western University and Jennifer Berdahl of University of British Columbia looked at a diverse sample of 65 women of colour in Canada and the U.S. for the study. Their paper, Do you see me? An Inductive Examination of Differences Between Women of Colour’s Experiences of and Responses to Invisibility at Work, was recently published in the Journal of Applied Psychology.

The study  examines how differences in race, immigration status, age, and organizational status – which determined the women’s proximity to social power – informed the types of invisibility they experienced, as well as their responses to invisibility. Although there is much research examining workplace mistreatment experiences of women in general, very little research explores how women of colour experience and respond to workplace mistreatment.

“The study offers a more theoretically complete understanding of the experiences of invisibility for a variety of women of colour at work,” said Bhattacharyya. “By interviewing a diverse sample of women of colour, we identified distinct forms of invisibility that made them feel unseen for their true selves”

Powerful and revealing interviews show the experience of invisibility was common, painful, and dehumanizing for women of colour, and identified four distinct forms of invisibility:

1. Erasure, invisibility in its most literal sense, means being unheard or unseen. Ninety-five per cent of interviewees reported experiencing erasure at work. East/Southeast Asian women experienced erasure the most acutely frequently;
2. Homogenization is being treated like a homogenous and interchangeable member of an unrelatable out group. Eighty-six per cent of interviewees reported homogenization, often describing being treated as virtually indistinguishable from other women of colour. Even though Black women made up less than one-fifth of the sample, they represented one-third of those who experienced homogenization most acutely and frequently;
3. Exoticization is a unique race and gender-based sexualization that made women of colour feel reduced to foreign objects of fascination and fetishization. Seventy-eight per cent of interviewees experienced exoticization. Although most participants across racial groups reported exoticization, a disproportionate number of those women were younger and of lower organizational status. Further, every Latina woman and all but one Black woman noted being exoticized; and,
4. Whitening is when one’s similarities to white people are highlighted and complimented and non-white racial/ethnic identities and cultural backgrounds discounted and ignored. Fifty-one per cent of interviewees reported whitening, which was confusing because it was framed as inclusion and praise, but undermined the women’s racial and cultural identities, making them feel invisible. Most of the interviewees who reported whitening had grown up in Canada or the U.S., were older, and/or had high organizational status.

Importantly, the study identified three distinct responses to experiencing invisibility in the workplace. How women of colour attributed causes of their invisibility, combined with their social power, shaped whether they engaged in withdrawal, approach, or pragmatic responses.

In general, women of colour with less social power at work experienced invisibility most strongly. They were more likely to blame themselves for their invisibility, and were more likely to engage in withdrawal (e.g., further staying quiet, making themselves small), which intensified their invisibility and marginalization. Women with more social power experienced less invisibility. They were more likely to blame the perpetrator for their invisibility, and were more likely to engage in approach tactics (e.g. speaking up strongly against an invisibility experience, challenging the perpetrator), which risked backlash. Women who attributed their invisibility to structural causes (e.g. systemic racism, systemic sexism) were more likely to engage in pragmatic tactics. Although least common among the interviews, such tactics often empowered women to engage in radical honesty with those who had made them feel invisible.

“Our findings offer novel insights for organizational practices around diversity and inclusion by highlighting the complexity that exists within women of colour’s experiences at work,” said Bhattacharyya. “Some are more invisible than others, and women of colour experience, and respond to, invisibility in different ways depending on their identities and positions. This also gives women of colour legitimacy and language about subtle workplace mistreatment experiences.”

While the paper’s findings provide insight into the unique marginalization of women of colour in the workplace, they also highlight the need to design more sophisticated practices around Equity, Diversity, and Inclusion (EDI) at work. In particular, there is a need to pay attention to different ways in which marginalized groups experience mistreatment at work, and design EDI policies and tools that address them accordingly. Typically, there is a blanket EDI approach and solution (e.g. gender bystander intervention training) that only serves a few. Organizations also need to create climates and conditions for dialogue, where radically honest conversations can occur in psychologically and socially safe environments that recognize structural barriers to women of colour’s visibility and inclusion in organizations.

The full text of the paper is available on the website of the Journal of Applied Psychology: https://psycnet.apa.org/fulltext/2023-45629-001.html

Authors:

Barnini Bhattacharyya, Assistant Professor, Organizational Behaviour, Ivey Business School at Western University

Jennifer L. Berdahl, Professor, Department of Sociology, University of British Columbia

---

JOURNAL

Journal of Applied Psychology

DOI

10.1037/apl0001072 

METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Do You See Me? An Inductive Examination of Differences Between Women of Color’s Experiences of and Responses to Invisibility at Work

Muffins that could be good for your health

Healthy and muffins are not usually two words we associate with each other. But a plant extract might help change that, at least a little bit

Peer-Reviewed Publication

NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY

 

IMAGE: RESEARCHERS TESTED DIFFERENT FORMULATIONS OF MUFFINS CONTAINING A PLANT EXTRACT TO SEE WHICH VARIETY APPEALED MOST. view more 

CREDIT: SCREENSHOT FROM: NUTRITIONALLY ENRICHED MUFFINS FROM ROSELLE CALYX EXTRACT USING RESPONSE SURFACE METHODOLOGY. FOODS. 2022; 11(24):3982. HTTPS://DOI.ORG/10.3390/FOODS11243982

Love muffins? We’re talking about a tasty, fluffy muffin that has no artificial additives and that simultaneously contains lots of beneficial nutrients. As remarkable as it might sound, a recently published study led describes the development of just such a new muffin in the journal Foods.

From muffins to functional food

The new super muffin has been named Roselle, because it contains calyx extract from the tropical plant Hibiscus sabdariffa, which is often referred to by the same name.

[caption id="attachment_79738" align="aligncenter" width="559"] Here's a look at the different formulations that researchers tested. Photo: Screenshot from Food article[/caption]

Hibiscus flowers have a beautiful red colour, and the calyx extract contains many valuable bioactive compounds, such as polyphenols, flavonoids, betaine and hibiscus acid. All of these components can be used to develop new products and functional food that may offer positive health effects, possibly also reducing the risk of chronic diseases.

The study also shows that Roselle muffins maintain their freshness for up to six days at room temperature, but with so many beneficial qualities, chances are they will be long gone by then.

Health benefits

The study is part of Re-FOOD (see factbox), a Norwegian-Indian collaborative project focusing on using and enhancing the value of rest raw materials of food processing.[faktaboks="1" stillopp="hoyre" storrelse="liten"/]

Professor Nutan Kaushik at Amity University in the state of Uttar Pradesh, India, points out the health benefits of antioxidants, especially when it comes to neutralizing free radicals, which can be an important contributing factor to serious illnesses.

Prefer natural food colouring

Roselle is also rich in anthocyanins. This is a dye that can be dissolved in water and yields a red, pink, purple, blue, blue violet or violet colour. The colour of food has a strong influence on how appetizing we think it is.

Artificial dyes are often clearer and more intense than natural substances. But the demand for natural dyes is increasing because of the concern that artificial dyes are harmful to our health.

Tasty, nutritional and long shelf-life

In the muffin study, 30 people tested a total of 17 recipe variants.

The aim was to find the best version of Roselle muffins relative to three important qualities:

• The muffin should should have a taste and texture that people like
• The muffin should have valuable nutritional properties
• The muffin should have the best possible shelf life without preservatives

Aim — the best possible response

The researchers measured and surveyed the test subjects' response to the pastry's colour, appearance, aroma, texture, fluffiness, elasticity, freshness and chewing resistance. The researchers used the Response Surface Methodology, to model and analyse how the test subjects’ reactions were affected by various factors. The aim of the method is to achieve the most positive response to what is tested.

Natural food colouring — good for our cells

[caption id="attachment_79737" align="alignright" width="352"] Hibiscus sabdariffa is frequently used in teas and juices. Photo: Colourbox.[/caption]

In terms of nutrition, the results suggest that the hibiscus extract provides muffins with high levels of antioxidants like phenolics.

These are substances believed to be able to prevent processes in the body that can damage cell membranes or the genetic material in our cells. There are several thousand different phenols, most of which are found in fruit, juice, wine, cocoa, tea, coffee, vegetables, flax seed, whole grains and legumes.[faktaboks="2" stillopp="hoyre" storrelse="liten"/]

Maybe not so healthy

The Roselle calyx extract obviously provides health benefits, but the muffin research is primarily good news for those of us who already eat muffins. Because there are some bitter tastes — figuratively speaking — in this muffin batter, in the form of unhealthy sugar, saturated fat and white flour.

Eva Falch is an associate professor at NTNU’s Department of Biotechnology and Food Science, and  a co-author on the study. She doubts that Roselle would be able to be classified as healthy in Norway.

[caption id="attachment_79735" align="alignright" width="100"] Eva Falch is an associate professor and head of the NTNU Food Forum. Photo: NTNU[/caption]

Underused resource

“Roselle calyx extract is an underutilized resource, and the  study primarily shows the potential of the plant extract. The researchers use the muffin as a model to say something about how ingredients and steps in the manufacturing process affect and change the properties of the final product,”Falch says.

New possiblities

Classifications and health recommendations, as well as taste and food culture, vary between countries.

“In food cultures where baked goods like this are part of the daily diet, Roselle muffins can contribute to increased nutritional value. To make a healthy version, the whole composition should be as good as possible, with little sugar, salt, saturated fat, and so on,” said Falch, who is also head of the NTNU Food Forum.

Animal models and a start-up

A next step could be to test this ingredient in products with a better nutritional profile, such as whole grain products, so that it can be part of a healthy diet.
Professor Nutan Kaushik, says the findings have helped in getting the acceptance among consumers as well as regulators.

“Next, we plan to  do study the health benefits on animal model and launch  a start-up company,” she says.

Moist muffins mould easily

Shelf life was the third factor the researchers investigated. When dry and semi-dry baked goods such as biscuits are left for too long, they can deterioriate both physically and chemically.  Muffins with a higher moisture content, on the other hand, are more vulnerable to bacteria, fermentation and mould. Mould and mould spores are destroyed by heat during baking, but as soon as the muffins are out of the oven, they are exposed to airborne mould spores.

… but Roselle keeps fresh without preservatives

Roselle muffins have no added preservatives. The beauty is that the antioxidant ascorbic acid is also found in the pastry. This is a chemical bond that can contribute to increased shelf life in food products. And when it comes to the effects of ascorbic acid on the human body, most of us know it by its common name, vitamin C. The tests showed that Roselle kept well for six days at room temperature, with no signs of mould or spores.

Reference: Marak, S.; Kaushik, N.; Dikiy, A.; Shumilina, E.; Falch, E.
Nutritionally Enriched Muffins from Roselle Calyx Extract Using Response Surface Methodology Foods 2022, 11, 3982.

---

JOURNAL

Foods

DOI

10.3390/foods11243982 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Nutritionally Enriched Muffins from Roselle Calyx Extract Using Response Surface Methodology.

The colors on these ancient pots hint at the power of an empire

Peer-Reviewed Publication

FIELD MUSEUM

 

IMAGE: A CERAMIC VESSEL FROM THE MOCHE REGION OF NORTHERN PERU WITH WARI-INFLUENCED PIGMENTS AND DECORATION TECHNIQUES. view more 

CREDIT: PHOTO COURTESY OF THE FIELD MUSEUM ANTHROPOLOGY COLLECTIONS (FM 2959.171668)

Color plays a huge role in our lives — the hues we wear and decorate with are a way for us to signal who we are, where we’re from, and what we care about. And it’s been that way for a long time. In a new study in the Journal of Archaeological Science: Reports, archaeologists compared the colors on pieces of ancient Peruvian pottery. They found that potters across the Wari empire all used the same rich black pigment to make ceramics used in rituals: a sign of the empire’s influence.

The Wari empire spread over Peru’s highlands and coastal areas from 600-1050 CE. “People sometimes think of the Inka as the first big empire in South America, but the Wari came first,” says Luis Muro Ynoñán, the study’s corresponding author and a research associate and former postdoctoral scientist at the Field Museum in Chicago. 

The Wari didn’t leave behind a written record (or at least a system similar to the one we use now). “Since they didn’t use writing, material culture — things like pottery — would have been an important means for conveying social and political messages,” says Muro Ynoñán. “The visual impact of these objects would have been super powerful.” Even little details, like using the correct shade of a color, could help signify an object’s importance and legitimacy as a part of the empire.

“I remember seeing some of these Wari-influenced pots as an undergraduate archaeology student in Peru, they're fascinating,” says Muro Ynoñán. “The rich black color on them is very distinctive, I’ve been obsessed with it for years.” Muro Ynoñán finally got to pursue his interest in the pigment in-depth during his postdoctoral position at the Field Museum. 

He and his co-authors, including Donna Nash, an adjunct curator at the Field and associate professor and head of anthropology at the University of North Carolina Greensboro, examined pottery from different regions under Wari influence, focusing on the chemical makeup of the black pigment used. 

The exact formulation of pigments varied from site to site, but overall, there was one striking similarity: many of  the Wari pots examined in the study used black pigment made from minerals containing the element manganese. 

“Some of the sites, specifically in northern Peru,used a different recipe for black, using iron- and calcium-rich minerals, before the Wari arrived, but after the Wari took over, they switched to the manganese-based recipes,” says Muro Ynoñán. The shift makes the authors suspect that the Wari empire asserted some sort of “quality control” over the pottery produced in different regions, perhaps even supplying artisans with the “correct” black pigment. “In general, black minerals are relatively easy to obtain from the valleys we looked at,” says Muro Ynoñán. But just any old black mineral didn’t fit the official Wari look — instead, he thinks that artisans may have been supplied with the manganese-bearing minerals from the Wari capital to produce the right shade of black.

The changes in hue are subtle, but Muro Ynoñán says that the symbolic meaning of using “Wari black” may have been very important. “In general in the Andean region, the color black is related to the ancestors, to the night, to the passage of time. In Wari times, the color was likely important for imposing a specific Wari ideology to the communities they conquered.”

While the colors on Wari pottery might indicate imperial control, the ceramics from different regions do maintain their own local character. “Local potters had a lot of flexibility in producing hybrid material culture, combining the Wari imperial style and decoration with their own,” says Muro Ynoñán. The ceramics were unified by the use of black pigments that were controlled and put in circulatation  by the Wari empire through its imperial trade channels, but from there, artists could put their own spin on their work.

“One thing I hope people will take away from this study is that every beautiful artifact you see in a museum was made by real people who were very intelligent and possessed specific technologies to achieve their goals,” says Nash, co-author of the study. “Further, these people shared technologies and made choices. Artisans talked to each other and learned from each other, but sometimes multiple ways of doing things, such as creating black lines and decoration on a decorated pot, co-existed.These different approaches to the same problem may have persisted because of wealth or class differences, but it may have been that some people were willing to try new things, while others preferred their traditions.”

###

 

---

JOURNAL

Journal of Archaeological Science

SUBJECT OF RESEARCH

People

ARTICLE TITLE

The Colors of the Empire: Assessing techno-decorative innovations in local, hybrid and intrusive ceramic pigments within the sphere of Wari cultural interaction, Peru

ARTICLE PUBLICATION DATE

7-Mar-2023