Meringue Christmas Tree

The Art.
    For my holiday party this year, I wanted to make an edible topiary to complete my table decor. I came across an idea for a beautiful meringue cookie topiary, so I decided to try my hand at making meringues. I was a little daunted by the three hour time commitment at first, but the small amount of active time meant that I could spend those three hours doing chores (read: watching tv). The cookies turned out wonderfully--nice and airy and not too sweet. Making the topiary was a breeze, especially because I used a couple cans of spray food color to tint the cone and the cookies.  This also meant I could rest easy knowing that everything was food-safe.

The Science.
    Meringue cookies are so light and crisp because they are mostly beaten egg whites and sugar. Egg whites are composed of water and protein, and when they are beaten at high speed the proteins begin to stick together, or "aggregate." The aggregated proteins make up a film that coats the air bubbles, and helps retain the bubbles in the mixture. Different conditions can cause egg whites to foam more efficiently, such as increasing the salt, acidity, and temperature [1]. This is why most meringue recipes call for room temperature eggs and cream of tartar. Pasteurization treatments can also increase the foaming performance of egg whites. Several groups have found that irradiating or ozonating egg whites increases protein aggregation and foaming, in addition to the sterilizing effects [2,3].

The Recipe.

Meringue cookies: (Makes 50)
3 large egg whites, room temp.
1 tablespoon pure vanilla extract
1/4 teaspoon cream of tartar
3/4 cup superfine granulated sugar
red spray food color

    Preheat oven to 200°F. In a large bowl, beat together egg whites, vanilla, and cream of tartar until soft peaks form. Gradually beat in half of the sugar, then beat on high until stiff peaks form. Fold in remaining sugar.

     Cover two baking sheets with parchment paper, sticking the paper down at the corners with a dab of meringue. Spoon meringue into an icing bag fitted with 1M tip, and pipe 2-inch stars onto baking sheets, 1/2 inch apart.  For the red cookies, spray 1/4 of the unbaked meringues generously with the red food color. I used Wilton Color Mist. (I really love this stuff, because tinting a batch of batter or icing deep red takes so much dye. By just spraying the tops, you can achieve the dark color quickly with less material.) Bake 2 hours, switching the top and bottom racks halfway through. After baking, leave cookies in oven to cool 1 hour with the door held ajar a couple inches with a spoon handle.

Topiary:
15" Styrofoam cone
green spray food color
1/2 cup powdered sugar (or royal icing)

    While cookies are baking, begin preparing your Christmas Tree. Place the Styrofoam cone on parchment paper and liberally spray with the green food color. Allow to air-dry several hours. In a small bowl, make an edible "glue" by adding a few drops of water to the powdered sugar.



    To affix the cookies to the "tree," dab a small amount of the sugar glue on the back of each cookie and press it on the tree. 

    For this spiral pattern, you can begin by making a spiral with the red meringues first, then fill in the rest with the white ones. Or, you can disperse the red ones evenly to look like ornaments.

    The meringue topiary was a big hit at the party, and added nice height to my holiday treats display. I highly recommend using color and height to liven up your edible spread. A little extra effort goes a long way to impress your guests.

1. O Chef, "Beating Egg Whites into Submission." http://www.ochef.com/223.htm
2. Liu, X. et al. "Effect of irradiation on foaming properties of egg white proteins." Poult. Sci. 2009, 88(11) pp 2435-41.
3. Uzun, H. et al. "Effects of ozone on functional properties of proteins." Food Chem., 2012, 134(2), pp 647-54.

Chocolate Candy Cane Cupcakes

The Art.
    One thing you must know about me is that I obsess about my baking. This past summer, I found a video tutorial on how to stripe a piping bag. The first thing that popped into my mind was to make cute little candy cane stripes on holiday-themed cupcakes. This idea has been waiting patiently in the back of my mind up till now, when the season is appropriate. To showcase this long-awaited striping effect, I made peppermint icing and used a large round tip. Chocolate cupcakes compliment the peppermint flavor perfectly, and mini candy canes add a little fun.

The Science.
    Not only does peppermint oil taste delicious, it also imparts antimicrobial properties. This is why food manufacturers use peppermint oil as a perservative [1].  Unfortunately, this essential oil is not very soluble in water and has a high volatility, so it will separate and evaporate over time. A recent publication has described a new method of creating peppermint nanoemulsions in order to overcome these obstacles [2]. An emulsion is a mixture of a hydrophobic substance (peppermint oil) and a amphipathic substance (ultrapure cornstarch) in water, where the amphipathic compound interacts with both the water and the oil and allows the mixture to stay in solution. Nanoemulsions are created by homogenizing the substances at very high pressure to create a very small particle size. Making the emulsified particles so small increases the number of amphipathic interactions and thus increases the solubility of the solution. In this way, the peppermint oil is protected from separating from the water content of the food, and retains its antimicrobial properties.

The Recipe.

Chocolate Cupcakes: (Makes 15)
1 cup sugar
1 cup flour
3/4 teaspoon baking powder
3/4 teaspoon baking soda
1/2 teaspoon salt
1/2 cup boiling water
1/3 cup cocoa
1 egg
1/2 cup milk
1/4 cup vegetable oil
1 teaspoon vanilla extract


    Preheat oven to 350^oF and adjust rack to center position. Line cupcake tins with liners. Combine sugar, flour, baking powder, baking soda, and salt in a medium bowl. In a small bowl, dissolve cocoa in boiling water to allow it to "bloom." In a large bowl, beat together egg, milk, oil, and vanilla. Add dry ingredients and beat on medium speed for 2 minutes. Stir in bloomed cocoa. Pour 1/4 cup batter into each cupcake tin, and bake 20 minutes. Cool on wire racks.

Peppermint Buttercream:
1/2 cup salted butter, softened
1/2 cup shortening
3-4 cups powdered sugar
1/2 teaspoon peppermint oil
No-taste red gel food color 

    Beat butter and shortening together in large bowl. Gradually beat in sugar until stiff, jagged peaks form. Beat in peppermint oil.



Decorating:
    Place a 1A round tip in a disposable piping bag. With a small paintbrush, paint four vertical lines of red gel food color on the inside of the piping bag.

    Fill bag with icing, and pipe onto parchment paper until the stripes come through. Pipe a swirl of icing on each cupcake and garnish with a mini candy cane.

 1. LisBalchin, M. et al. "Bioactivity of selected plant essential oils against Listeria monocytogenes." J. Appl. Microbiol, 1997, 82, 759-762

2. Liang, R. et al. "Physical and Antimicrobial Properties of Peppermint Oil Nanoemulsions."
J. Agric. Food Chem, 2012, 60 (30), pp 7548–7555

Gingerbread Cupcakes with Eggnog Icing

The Art.
    My youngest sister was born a couple days before Christmas, and has endured many hardships, what with Baby Jesus stealing her birthday thunder and all.  One year I was particularly insensitive and made her a giant gingerbread man birthday cake, because I wanted to try out my new novelty cake pan. Fortunately, my sister loved the idea and it became a tradition for her to have a gingerbread man every year--until the John the Baptist Incident.
    That particular year, my sisters and I were cleaning up after dessert and discovered that all that was left of the poor gingerbread man was his head. In a moment of comedic genius, we slathered his severed neck in red food coloring and mounted his head on my mother's sterling silver platter. My mother, drawn to the kitchen by our hysterical laughter, was horrified to find what her heathen children had done. She forbade us to ever make a gingerbread man again, and as penance we had to read a chapter from our Illustrated Children's Bible every morning for the next few weeks. Despite her valiant effort to recondition us, I still think Gingerbread John the Baptist was hilarious. Even today, I couldn't help giggling a little as I made these gingerbread cupcakes.

The Science.
    If we had really been true to form when making our gingerbread man blood, we would have used molasses, not food color. This syrup is what gives gingerbread its robust and distinctive flavor, and differentiates it from spice cake. Molasses is a byproduct of sugar production, made from the liquid produced when sugar cane juices are boiled to crystallize the sugar. In addition to some unrefined sugars, molasses contains many vitamins and minerals. It has particularly high levels of phenolic compounds, which have been reported to be strong antioxidants [1]. A group in Italy recently published a study investigating the antioxidant benefits of molasses, and they found that treating cells with molasses increased cell viability under oxidative stress, as well as decreased cellular reactive oxygen species [2]. While this is wonderful evidence that people should substitute molasses for other sweeteners, I'm doubtful this will happen since molasses has a very strong flavor that has gone out of style in the last century.

The Recipe.
 
Gingerbread Cupcakes: (Makes 30)
2 1/2 cups all purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1 teaspoon salt
2 tablespoons ground ginger
3/4 teaspoon cinnamon
3/4 teaspoon allspice
1/4 teaspoon pepper
1 1/2 cups sugar
4 teaspoons grated ginger root
1/2 cup vegetable oil
3 eggs
3/4 cup molasses
3/4 cup buttermilk

    Preheat oven to 350^oF and adjust racks to lower and middle position. Line cupcake tins with liners. Combine flour, baking powder, baking soda, and spices in medium bowl. In large bowl, whisk together remaining ingredients. Add dry ingredients, and beat on medium speed for 2 minutes. Pour batter into tins with 1/4 cup measure and bake for 20 minutes, or until tester comes out clean. Cool on wire racks.

Eggnog Icing:
1/2 cup salted butter, softened
1/2 cup shortening
4-5 cups powdered sugar
1/4 teaspoon cinnamon
1/4 teaspoon nutmeg
1/2 cup eggnog

     In a large bowl, beat together butter and shortening. Gradually beat in 4 cups sugar, 1/2 cup at a time. Beat in remaining ingredients. If icing is too soft to pipe, add more sugar.

 
Decorating:
    Fill a piping bag with icing and add a 199 star tip. Pipe a dab of icing in the center of the cupcake. Add a ring of stars around the periphery. Continue to pipe stars from the outside to the center. Add a cinnamon stick for garnish.

1. Payet, B. et al. "Comparison of the concentrations of phenolic constituents in cane sugar manufacturing products with their antioxidant activities." J. Agric. Food Chem, 2006, 54:19 (September 20).
2. Valli, V. et al. "Sugar cane and sugar beet molasses, antioxidant-rich alternatives to refined sugar." J Agric Food Chem, 2012, Nov 28. [Epub ahead of print]