Color Changing Eggless Blood Orange Jello Poke Cake

This is a delicious and eggless blood orange poke cake with layers of blood orange flavor - in the cake, in the gelatin free jello, as well as in the cream frosting. This soft eggless cake with blood orange juice and zest in layers is one of the best desserts to serve for festive occasions. 

I received samples from Melissa's Produce, Anolon, and Taylor and Colledge to aid the process of recipe development. Best food starts with the best ingredients and these products are simply the best! 

First, Melissa's Blood oranges are loaded with tons of anthocyanins with deep red colored flesh.

Next, Taylor and Colledge extract pastes give the perfect flavor in baked goods and it is always my go to  choice to use for any recipe. Check here for delicious recipes using almond extract paste, vanilla extract paste, Lemon extract paste, and Lavender extract paste. If you haven’t tried these, do try now and do not miss on the flavors.

Finally, Anolon pans are the best! They transfer heat uniformly and quickly resulting in even baking results every time. Whether you bake cookies, breads, or cake, it is a must to use Anolon pans for best results.

Have you ever wondered why baked goods with blood oranges turn to purple/blue color while other citrus (lemon, lime, or orange) based cakes/baked goods do not? This is explained by a simple science experiment from your school time. Before going into it, it is important to know what constituents in the blood ranges give its color. Let’s get in with it.

What are anthocyanins?

Anthocyanins are a class of chemical compounds that belong to the flavonoids ( a wide group of phenolic compounds), and these pigments are responsible for the color in many veggies and fruits. In citrus, these pigments are concentrated in the flesh and sometimes in the rind. In blood oranges, these anthocyanins are the ones making it red in color and depending on the quantities of the pigments, there are variations in the red color in these oranges. The dark coloration is also seen on the exterior rind of the fruit. This concentration of the pigments also depends on the specific weather conditions. Low temperatures at night is vital for the oranges to develop a deep red color.

A little chemistry……..

Baked goods have basic ingredients and may also contain acidic ingredients. Acidic, or basic, is determined by the hydrogen or hydronium ion concentration. pH is the logarithmic measure of the hydrogen ion in solution or the substance. In simple terms acids are those substances that give H+ in solution and the acidic ingredients include citrus juices, vinegar, buttermilk etc. They aid in giving a fluffier texture to the cake. Whereas bases are those that would accept the H+ ions and the basic components in most of the bakes are baking soda and baking powder (Sodium carbonate and sodium bicarbonate). When the acidic and the basic ingredients react in your cake mixture, in bakes, the carbonates will react with acids producing carbon dioxide as one of the products of this neutralization reaction, and this helps in leavening the cake. 

Now for the pH and blood oranges, and their effect on baked goods:

Like all citrus fruits, these blood oranges are also acidic, but they are less acidic than a Navel Orange. The pH of the blood orange juice is around 3.3 to 3.8. These anthocyanins are sensitive to pH.  In simple terms, they change into a different form when the pH changes. That means, when the juice comes in contact with a base, the color changes and these anthocyanins take a different structural form. The flavylium cation gives the red color at lower pH and it changes to around 4, the anthocyanins in blood orange changes to purple color (the flavylium cation changes to quinoidal species). (Reference here). 

Blood orange and this cake: When the cake bakes, the base from the baking powder and baking soda react with the acidic vinegar used. This cake recipe uses milk and condensed milk which also have a pH of 6.8 and 6.2 respectively, in the acidic range. The apple cider vinegar has a ph range of 2-3. These acidic components neutralize the base, producing carbon dioxide and thereby leavening the cake. The pH changes as the acids are neutralized and it would no more be in the range of 2-3. 

This is the reason why the beautiful reddish pink cake batter in this Blood Orange bundt cake changes to blue color as the reaction proceeds inside the oven when the cake bakes. In this cake, only the zest is used in the batter, and the anthocyanins are not present in enough concentration (though blood orange zest has some) to make the effect. The moment the blood orange gel mixture is added in this poke cake, the anthocyanin rich blood orange comes in contact with the cake that doesn’t have a pH around 2. So the jello changes to purple color and is edible even though it might have undergone some structural change. The color change doesn't happen immediately, takes about 30 minutes or longer.

What are the options to use this color change, and option  to keep the beautiful color of this blood orange?

The next time you include some blood orange juice, make sure to note these color changes specified above. The resulting change doesn’t harm us and the baked goods are totally great to eat. This gives an opportunity to make naturally colored and flavored cakes for many occasions, for birthdays, for themed parties, and for especially Halloween. This Halloween try this experiment in your spooky baked goods. The color of the blood orange juice can be maintained when you make a glaze, like in this cake, (which is widely used), drinks, and frozen yogurt (check this Blood Orange Frozen Yogurt, one of our favorites to have when blood oranges are in season). There are a few other recipes utilizing the blood orange juice retaining its color too. Stay tuned and check the blog frequently for more blood orange recipes.

Done with the science and let’s talk about what is required to make this delicious blood orange poke cake.

All purpose flour -The base for the cake.

Baking powder and baking soda - leavening agents

Milk - taste enhancer, as well as emulsifier

Condensed milk - adds sweetness, enhances flavor and texture

Taylor and Colledge vanilla extract paste - adds the best vanilla flavor to the cake

Blood oranges - The star flavor component of this cake. Juice and zest are used in this recipe

Agar agar powder - vegan gelling agent to make jello

Sugar - Sweetens the plant based jello

Salt - enhances flavor

Butter - The fat used for the cake

Heavy cream - To frost the cake

Powdered sugar - To sweeten the frosting

How many servings are in this cake?

This cake made in an Anolon pan makes about 16-20 servings depending on the size it is cut into. This is a great size to make for any special occasions like your spring party!

Can this recipe be scaled up?

Yes, this recipe can be scaled up or down based on your requirements. Make sure to bake in a proportional pan size when scaling up or down.