3 things you should know about pickles, Solar Cycle 25, and pig organs
Meet Renée-Claude Goulet and Michelle Campbell Mekarski.
They are Ingenium’s science advisors, providing expert scientific advice on key subjects relating to the Canada Agriculture and Food Museum and the Canada Science and Technology Museum. Jesse Rogerson, formerly the science advisor for the Canada Aviation and Space Museum, continues to lend his expert voice to the Channel.
In this colourful monthly blog series, Ingenium’s past and present science advisors offer up three quirky nuggets related to their areas of expertise. For the November edition, they tackled the topics of pickles, Solar Cycle 25, and pigs as promising organ donors for humans.
Pickling is a great way to prevent food waste and preserve garden harvests, by preventing microorganisms from proliferating and rotting the food.
Hey, there’s some science in my pickle!
Did you know November 14 is National Pickle Day? A delicious snack, pickles undoubtedly deserve their day to shine, but in the broader sense, what we are celebrating is an ancient food preservation technology. For millennia, pickled foods have carried humans through times of scarcity, allowed us to keep harvests from spoiling, and enhanced the digestibility and nutritional value of certain foods.
Once food is harvested, the biochemical activity inside cells and tissues continues — burning stored carbohydrates and releasing CO2, heat, and moisture. Tissues eventually start to die, opening up the food to microorganisms that inhabit all our environments and surfaces. Food, though it can appear clean, is rarely ever sterile. It can host various fungi such as yeasts and molds, and many types of bacteria.
To stop food from rotting, we need to stop these microorganisms that feast on it — and which can make us sick. They need specific conditions to live, and salty, acidic environments are their enemies. But not all pickles are the same! We can pickle using a solution of water, vinegar, and salt, or we can pickle through a more ancient method: lacto-fermentation.
Most of our grandmothers’ canning recipes — and pickles found in the grocery store — use the vinegar method. This creates a nasty environment for the microbes; it stops them in their tracks and keeps our food edible for long periods.
Lacto-fermentation, on the other hand, skips the vinegar. By simply putting fruit or vegetables in a salty brine, certain naturally occurring microbes will perish, while others — lactic acid bacteria, which are harmless to humans — will start to proliferate. These consume carbohydrates in the food, and release lactic acid and other waste products. The bacterially produced acid prevents the other “agents of rot” from setting up shop and spoiling the food. Once the acid levels become high enough, the lactic bacteria slow down and we are left with a tangy, lacto-fermented product. This is how kimchi and sauerkraut are made.
This National Pickle Day, why not get familiar with one of these pickling methods and try it for yourself? Those cucumbers in the crisper will thank you!
By Renée-Claude Goulet
The small dark splotches on the surface of the Sun are known as sunspots; on average each sunspot is about the size of the Earth.
The Sun is starting to rev its engine
Solar Cycle 25 has begun! Based on careful observations, it appears that the new solar cycle began at the end of 2019, which means the Sun is starting to become more active. But what is a solar cycle? And should you worry about the Sun getting more active? To answer these questions, we have to take a step back.
Humans have been observing the Sun as far back as we can know, and scientists have been observing the Sun since at least the time of Galileo over 400 years ago! Early on, one key observation noted that the Sun has ‘spots’ — small and dark blotches — randomly strewn across its surface. For decades, scientists tracked these sunspots: their formation, their dissipation, looking for patterns. Scientists even used sunspots to calculate how fast the Sun rotates on its own axis.
Then, in 1775, a scientist from Denmark noticed that the number of sunspots visible on the surface of the Sun follows a semi-periodic pattern. Over the course of about 11 years, the number of sunspots on the surface of the Sun at any one time goes from very small (or none), increases to a large number, and then returns to a very small number. These 11-year cycles are now known as Solar Cycles.
In the centuries since then, we have learned that sunspots are caused by areas of particularly strong magnetic fields. In fact, the magnetic field in the location of the sunspot is so strong, it prevents some of the heat within the Sun from escaping — making the area cooler* and appear darker. Along with the number of sunspots, the Sun also increases and then decreases the number of solar flares and coronal mass ejections.
These phenomena (sunspots and solar flares) are related to the Sun’s magnetic field, and the Solar Cycle itself is caused by the flipping of its North-South polarity. That’s right, every 11 years, the Sun’s north pole becomes its south pole and then flips back again!
Now, this 11 year cycle isn’t perfect (sometimes it's shorter, sometimes it's longer), which can make it difficult to determine when the next cycle will begin. Based on the observations of sunspots over the last year, NASA solar scientists have dubbed December 2019 as the official beginning of Solar Cycle 25 (the twenty-fifth 11-year-long cycle since reliable records began). This means that over the next five years, more and more sunspots will be visible on the surface of the Sun. It also means that more and more solar flares and coronal mass ejections will occur.
Now, should you be worried? The answer is no; the Solar Cycle doesn’t have an impact on our weather or climate. In fact, on the plus side, the increasing solar flares will lead to more and more awe-inspiring aurora!
*By cooler, I mean 3,500 C, which is about 1,000 degrees cooler than the surface of the Sun!
By Jesse Rogerson
Thousands of people across Canada are waiting in desperate hope for an organ transplant, but shortages mean they might not receive one. Could gene-altered pigs be the solution?
Pigs give hope to humans awaiting organ transplants
Every year, the number of Canadians diagnosed with organ failure rises. Despite the thousands of successful organ transplants performed every year, there are never enough donors to save the life of every person in need of a transplant. According to Canadian Blood Services, over 4,000 Canadians are awaiting organ transplants; about 250 of these people will die within a year while waiting for a transplant.
A key reason for the shortage is that only about one percent of people die in such a way that their organs can be donated. Since the organs still have to be functioning, most organ donations come from patients suffering brain death. Additionally, organs are only viable for a few hours after removal, meaning the donor and the recipient need to be geographically close (difficult in a country as large as Canada).
One possible solution to the organ shortage crisis is xenotransplantation, or the donation of organs from a non-human donor. This idea is not new; in fact, clinicians have been attempting various types of xenotransplantation for hundreds of years (blood transfusions and skin grafts being some of the older types). Heart valves from pigs have been regularly and successfully used since the 1960s.
Though xenotransplants solve the problem of supply and demand, they come with another critical problem: evolution. Biological differences between species including genetic viruses, organ structure, and immune systems mean that xenotransplants are often rejected by the body, leaving the patient in a worse position. However, with new advances in genetic engineering — such as CRISPR — it now seems possible to alter the genes of the donor organism, allowing our bodies to receive these organs and tissues without issue.
Pigs seem to be the best candidate animal for human ‘replacement parts.’ Pigs are already widely cultivated worldwide for food, they grow quickly, and their anatomy is similar to humans. Tissue transplants from gene-edited pigs are already being tested in humans, including skin, corneas, and pancreatic cells to treat diabetes. Organs — being more complex — are a bigger challenge. Worldwide, several labs are exploring which genes need to be altered to allow successful organ transplants — but they are not there yet.
Xenotransplants may seem like a modern-day Frankenstein story rife with its own ethical implications, but this idea gives desperate hope to millions of people worldwide who are dying from organ failure. Combining agriculture, medicine, and genetics may make guaranteed organ transplants a not-so-distant reality, offering second chances at life.
Xenotransplants may be the future of medicine, but we’re not there yet. Register your intent to become an organ donor here.
By Michelle Campbell Mekarski