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Our Scientist Takes on Thomas Jefferson

...his vanilla ice cream recipe, that is.

Karen Z. —  March 13, 2015 — Leave a comment

Hear “vanilla” and what’s the first thing that comes to mind?

Ice cream, right?

While we were researching vanilla for this year’s Orchid Show (now in its final weekend), we kept discovering new scoops on vanilla ice cream.

PHOTO: Plain vanilla ice cream cone.First we learned that one-third of all the ice cream that Americans eat is vanilla.

Next, we learned about vanilla beans’ different flavors—at a tour of the Nielsen-Massey Vanillas facility in nearby Waukegan. (Who knew that vanilla extract was produced right here in Chicago?)

And then we came across Thomas Jefferson’s handwritten recipe for vanilla ice cream at the Library of Congress—such a beautiful document that we included a copy of it in the Orchid Show. (The knowledgeable staff at the Library of Congress pointed out that there’s a second recipe on the back of Thomas Jefferson’s vanilla ice cream notes—for the Savoy cookies to accompany it.)

All those moments dovetailed nicely when our own orchid expert, Pati Vitt, Ph.D., got inspired to make her own homemade vanilla ice cream. Naturally, as a scientist, she set herself a bigger challenge: to tackle Jefferson’s thorough (albeit old-fashioned) recipe, using three different types of vanilla beans kindly provided by Nielsen-Massey.

We had to document Dr. Vitt’s ice cream-making adventure: see how she interpreted Jefferson’s recipe—and what three guest chefs/tasters had to say about the flavor—in our video (view on YouTube).

PHOTO: Jefferson's vanilla ice cream recipe: Holograph, 1780s. Manuscript Division, Library of Congress.

Holograph recipe, 1780s. Manuscript Division, Library of Congress Bookmark this item

Thomas Jefferson’s Ice Cream

(Jefferson’s lovely script can be hard to decipher, so here’s the recipe’s text in full.)

2 bottles of good cream
6 yolks of eggs
½ pound sugar

  • mix the yolks & sugar
  • put the cream on a fire in a casserole, first putting in a stick of vanilla.
  • when near boiling take it off & pour it gently into the mixture of eggs & sugar.
  • stir it well.
  • put it on the fire again stirring it thoroughly with a spoon to prevent it’s [sic] sticking to the casserole.
  • when near boiling take it off and strain it thro’ a towel.
  • put it in the sabottiere*
  • then set it in ice an hour before it is to be served. put into the ice a handful of salt.
  • put salt on the coverlid of the Sabottiere & cover the whole with ice.
  • leave it still half a quarter of an hour.
  • then turn the Sabottiere in the ice 10 minutes
  • open it to loosen with a spatula the ice from the inner sides of the Sabottiere.
  • shut it & replace it in the ice
  • open it from time to time to detach the ice from the sides
  • when well taken (prise) stir it well with the Spatula.
  • put it in moulds, justling it well down on the knee.
  • then put the mould into the same bucket of ice.
  • leave it there to the moment of serving it.
  • to withdraw it, immerse the mould in warm water, turning it well till it will come out & turn it into a plate.

*Footnote from the Library of Congress: A “sabottiere” is an ice cream mold (“sorbetière” in modern French).

Vitt’s notes:

  • You can use the recipe without modification, just cooling the mixture in an ice bath and then in the refrigerator overnight.
  • Freeze according to your ice cream maker’s instructions.
  • One tablespoon of vanilla extract may substitute for the vanilla bean.
  • The recipe makes about 4 pints (2 quarts, or one ½ gallon).

BONUS RECIPE!

Ice cream wasn’t the only vanilla treat on Vitt’s mind: she also canned a batch of vanilla spice apple butter (we shared it in a meeting—delicious!) and made her own vanilla sugar. Vitt agreed to share her recipe—and presented it all so charmingly, with handcrafted labels, trims, and tags, that we had to include a photo, too. 

Vanilla Spice Apple Butter

PHOTO: Pati Vitt's vanilla apple butter.

Vitt not only agreed to share her recipe for vanilla apple butter with us—but presented it all so charmingly, with handcrafted labels, trims, and tags.

Wash, core, and slice 8 to 12 apples (Granny Smiths, or a mix of varieties) to fill a 6-quart crockpot to about 1½ inches from the top; add ½ cup of apple cider. Cook until completely soft—about the consistency of apple sauce.

Using a food processor, sieve, or Foley mill, puree the sauce. Put the mixture back into the crockpot, along with half of a fresh vanilla bean. Cook several hours on the “low” setting of your crockpot until the extra liquid cooks off and the mixture begins to thicken. (Place the lid of your crockpot slightly off kilter to allow steam to escape. This will speed up the evaporation and thickening of the mixture.)

After the apple butter begins to thicken, add ½ cup sugar and the juice of one lemon. Cook an additional 30 minutes. Stir in cinnamon to taste, plus a pinch each of ground cardamom and cloves. 

Pour into hot, sterilized jars and place in a canning bath according to your canner’s recommendations for applesauce—usually about 10 minutes.

For more ideas—sweet and savory—for cooking with vanilla, check out our February issue of the Smart Gardener.


©2015 Chicago Botanic Garden and my.chicagobotanic.org

Growing a Bean in a Bag

Or, How to Train Your Plant Part 2 1/2

Kathy J. —  May 26, 2013 — Leave a comment

Garden blog followers may remember that in “How to Train Your Plant” I demonstrated a way to grow a bean seed in a plastic bag to test geotropism. I started working on that project around Thanksgiving week last year. At that time, I started a few bean bags just to see what would happen. I kept one seed growing in the bag all winter, adding water as needed.

PHOTO: A ziptop bag was used as a container to grow a bean plant. Roots, stem, leaves, and the remains of the original seed are visible.

The bean plant grew for five months, leaning toward the window in my office.

The plant produced a white flower about a month ago. I should have taken a picture. Now this week I discovered a seedpod growing where the flower had been! In the picture, you can see the wilted flower petals still hanging from the tip of the reddish colored pod. Botanically speaking, this is the fruit of the plant, even though you might not think of beans as fruit in your diet.

PHOTO: a red bean pod, about 2 and a half inches long is attached to the stem of the plant.

The red fruit was hidden under the leaves.

So if you try this activity, and you stick with it for six months, you, too, may be rewarded with a little treasure!


©2013 Chicago Botanic Garden and my.chicagobotanic.org

This year, it sure felt like spring was a long time coming — especially compared to last year when it seemed that we went straight into summer! I wonder how the wildflower timing of spring compared to previous years in the Chicago area…

Mayapples, April 25, 2012

Mayapples, April 25, 2012

Mayapples, May 2, 2013

Mayapples, May 2, 2013

For several years now, I’ve been working on a web-based citizen scientist project, called Project BudBurst, with colleagues at the National Ecological Observatory Network (NEON). We study the phenology — the timing of natural events like blooming, fruiting, and leaf fall — of plants around the country. Our participants track when plants bloom in their area, and we compare the reports to records from other parts of the country.

You can help us collect data! Sign up to help at Project BudBurst.

For instance, I’ve been tracking when the first forsythia flower opens on the plants near the Garden’s front gate since 2007. The earliest bloom I have on record in that time was last year, on March 15, 2012. The latest first flower for this specimen was this year, on April 20, 2013. In 2007 and 2008, however, we also had first flowers in mid-April (April 16, 2007, and April 17, 2008, respectively). So, as we look back in time, this year’s bloom time doesn’t feel quite so late. In the graph below we show the variation in flowering dates (using Julian dates, which standardize for differences in dates between nonleap and leap years).

forsythia data

In the Chicago area, we have a wealth of phenology data collected by the authors of our local flora, Plants of the Chicago Region by Swink and Wilhelm (1994). While they were gathering data for their book, they recorded when they saw plants in bloom from the late 1950s to the early 1990s. They record the forsythia bloom period as April 25 to May 5. So, when we look still further back in time, our “late” spring is much earlier than it has been in the past.

I took a similar look at several other species, both native and nonnative, for which we have both Project BudBurst data and data from Swink and Wilhelm’s book. About 70 percent of the species have earlier flowering dates in the last six years compared to those recorded by Swink and Wilhelm. Some of the species that have advanced their flowering dates are in the table below.

Species Earliest First Flower Observations
Common name
Genus species
Swink & Wilhelm
1950s – 1990s
Project BudBurst
2007 – 2012
Days
Advanced
Forsythia
Forsythia x intermedia
April 25 March 15 -40
Spiderwort
Tradescantia ohiensis
May 14 April 12 -32
Dogtooth violet
Erythronium americanum
April 6 March 20 -17
Red Maple
Acer rubrum
March 20 March 6 -14
Mayapple
Podophyllum peltatum
May 1 April 17 -13
Lilac
Syringa vulgaris
May 3 March 20 -44
Black locust
Robinia pseudoacacia
May 9 April 20 -19
Bradford pear
Pyrus calleryana
April 15 April 13 -2

Plant phenology, particularly when plants leaf out and bloom in the spring, is remarkably sensitive to the annual weather. Looking at phenological records over much longer periods of time can tell us a lot about how the climate is changing. Many scientists are comparing contemporary bloom times with historic bloom times recorded by naturalists like Aldo Leopold in the early 1900s, and Henry David Thoreau in the mid 1800s, as well as records kept by farmers, gardeners, and others interested in the natural world. Two of the longest phenological data sets are those maintained for cherry blossoms in Japan (dating back to 900 AD) and for grape harvest dates by winemakers in Switzerland (dating back to 1480 AD).

Plants have so much to tell us, if we take the time to listen!


©2013 Chicago Botanic Garden and my.chicagobotanic.org

How to Train Your Plant II

Part 2: Using Light

Kathy J. —  March 8, 2013 — Leave a comment

Blog followers will remember that in the first “How to Train Your Plant” post, we demonstrated how plants respond to the gravitational pull of the earth. Geotropism is difficult to overcome, but that didn’t stop me from trying to make a plant grow sideways through a maze. You can try this activity at home.

You will need these items:

  • a shoebox (or any kind of box)
  • cardboard to make dividers
  • duct tape (or any opaque tape)
  • soaked bean seeds—I used different beans from a soup mix
  • a container with soil
PHOTO: The materials for the maze are displayed.

You’ll need a shoe box, cardboard dividers, seeds, a pot with soil medium, and of course scissors and tape for constructing the maze.

Stand the box on its side. Then cut two pieces of cardboard to fit in the box and make divisions. You’ll want these to fit as snugly as possible inside the box, but they don’t have to be perfect. The tape will fix that. Cut a large window in each divider. Cut a window on one end of the box. Tape the dividers in place as shown in the picture.

PHOTO: The maze assembly is shown in the shoebox. There are two dividers with cut out windows and a whole in the side of the box for light to shine sideways on the sprouting bean seeds.

Pardon the crude appearance of this maze. I wasn’t going for style points.

Plant the seeds in the soil and put the container on the side opposite of the hole you cut. Just for fun, I used several different seeds from a bean soup mix to see if one kind would get through the maze better than the others. It was like a bean-seed “race.” You can try whatever you like.

Make sure the holes in the divisions are big enough to allow lots of light in from the side, and don’t vary the height too much. Remember, we are fighting the plant’s tendency to grow up—if it’s too challenging, it won’t work. Trust me, I learned this the hard way.

When the maze is complete, give your beans a last bit of water, and maybe a kiss, and then close the box. Apply tape along the top edge, to secure it and reduce light. Then put it next to a window and wait.

And wait.

It’s going to take a few weeks. Remember, horticulturists are very patient. Open the box every few days or so to be sure it has not dried out. Add a little water, but only enough to moisten the soil if it is very dry.

When you see the bean plant emerging through the open window in the box, open it and take a look. How long this will take will depend on the kind of beans you use, how far the plant has to grow, and how warm the room is.  

The beans have sprouted and are moving toward the light

The beans have sprouted and are moving toward the light

 It took my beans about five weeks to grow through the second window.

 

PHOTO: all of the bean sprouts are leaning toward the light.

The beans were definitely torn between growing up and growing in the direction of the light.

 

The winning sprouts, which I believe were lentils, did not actually make it through to the last window when I took this picture, and I’m not sure it has enough “umph” to do it. Still, notice how all of the plants leaned toward the light and most of them grew through the first window. That is a positive result!

What is going on here?

This activity demonstrates phototropism. Photo is the Latin word for “light,” and you will remember that a tropism refers to an organism’s response to stimulus, so that phototropism means plants grow toward the light.

It makes sense for plants to reach for the light because they need light to make sugars, their source of energy. Normally, growing up against the pull of gravity is also growing toward the light. In this activity, we changed that condition, forcing the beans to deviate from their normal course to get the light they needed.

The sprouts that grew the farthest and were closest to completing the maze had leggy stems that would not support growth upward to the last window. If I leave them a few more weeks, they could possibly grow along the bottom and then up the side of the box. I’ll have to wait and see.


©2013 Chicago Botanic Garden and my.chicagobotanic.org

Project Overview:
Shannon Still and Nick Jensen work on a project studying the impact of climate change on the distribution of rare plants in the western United States. The grant, funded through the Bureau of Land Management (BLM), examines the changes in projected species distributions between now and 2080. The goal of the research is to help BLM to make informed management decisions regarding rare plants. The research takes them to many exciting destinations as they search for rare plants in the west.

 

habit of Enceliopsis argophylla

Habitat of Enceliopsis argophylla, which thrives in gypsum-rich soil.

The silverleaf sunray (Enceliopsis argophylla),  is a photogenic species in the Asteraceae, or sunflower, family. This rare plant grows in basal clumps of silver-colored, hairy leaves with flowers extended on long stalks, and the entire plant may reach 2 feet tall. The flowers nod with maturity.

The large yellow daisy flowers are 3 to 4 inches across when open. They are quite a sight and stand in stark contrast to the habitat. Due to the extreme habitat, silverleaf sunray offers one of the more striking photo opportunities as the plants grow from a barren landscape.

Silverleaf sunray on a barren hillside.

Silverleaf sunray on a barren hillside


Nick Jensen with a silverleaf sunray.

Nick Jensen with a silverleaf sunray

These gems are found in Clark County, Nevada, east of Las Vegas in the Lake Mead area. They are also found in Mohave County, Arizona, close to Lake Mead.

The habitat for the silverleaf sunray has been encroached by Lake Mead and is threatened by off-highway vehicle use to a minor extent. The habitat in which the sunray grows is easily damaged due to the fragile soil environment (see photos to left) in which the species lives. Much like the dwarf bear-poppy (Arctomecon humilis), the silverleaf sunray grows in a gypsum-rich soil that typically has a healthy soil crust. Damage to this crust can allow invasive plants to grow more easily.

The Bureau of Land Management lists the silverleaf sunray as a sensitive species in Nevada and the species was considered, but rejected, for protection under the Endangered Species Act. Around Lake Mead the silverleaf sunray grows with the golden bear-claw poppy or Las Vegas bear-poppy (Arctomecon californica), a federally listed species. So while the species is not federally listed, the habitat is often protected due to the proximity of other federally listed rare plants.

Side view of the silverleaf sunray flower.

Silverleaf sunray is a striking plant that grows in close proximity to urban and recreation areas. If you are ever in the Las Vegas area, it is worth traveling the short distance to see these plants.


©2013 Chicago Botanic Garden and my.chicagobotanic.org