Why Do Some Ice Creams Melt Faster Than Others?

If you leave a carton of ice cream out in the hot sun, you may be surprised at how long it lasts before turning into a sugary soup. Some ice cream brands just refuse to melt. Most ice creams start simply with milk of a high percentage, but not all ice creams are made equally.

How quickly the ice cream melts is directly related to its overrun. Overrun is the percentage of volume increase of ice cream greater than the volume of mix used. For example, if 1 liter of mix becomes 2 liters of ice cream, the product has an overrun of 100%. Most low quality brands have overruns of 100% to 120%. This allows companies to stretch their resources and easily produce a large supply. As a result, production does not cost much, and consumers can buy ice cream for a lower price.

Higher quality brands have an overrun of 25% to 90%. Standard and premium products contain a higher fat content than economy brands, and incorporate less air into the ice cream. Unfortunately, this means that production is more expensive.

Due to the wide range in overrun, 1 pint of ice creams costs anywhere from $1 to $8. Even though you are paying for quality, we all know that Haagen-Dazs didn’t spend anything near $6.99 to manufacture that tiny little carton.

The rate at which ice cream melts also depends on the amount of emulsifiers and stabilizers in the ice cream. An emulsion is a mixture where two liquids mix, but do not combine into one uniform, homogeneous substance. Ice cream is simply an emulsion of milk fat dissolved in water. However, the mixture is unstable, and at room temperature separates into fat and water. This results in unappetizing lumps of fat and watery ice cream. In order to prevent this, companies use emulsifiers or stabilizers to improve the texture of their products.

Milk fat immersed in water

Milk fat immersed in water

Stabilizers reduce the iciness of ice cream and prolong shelf life. Each time ice cream leaves the freezer, it melts, and when it returns, it refreezes. To make smooth ice cream, ice crystals must be very small, so the freezing process must happen rather quickly. At factories, machines rapidly cool and churn ice cream to promote creaminess. However, home freezers solidify ice cream at a much slower rate than factory machines, which results in larger ice crystals. This produces a rough, icy texture.

Stabilizers add fat to ice cream. Added fat slows the melting of ice cream, so ice cream softens rather than completely melts. This prevents ice cream from becoming watery and mushy every time it sits on the counter. As a result, the ice cream won’t refreeze into large crystals and its texture will remain smooth even after it leaves and reenters the freezer.

Ice cream companies use stabilizers such as guar gum, locust bean gum, carrageenan, xanthan gum, polysorbate 80, monoglycerides, and diglycerides. Most are white powders that help thicken the mixture.  Moreover, egg yolks are also very popular for homemade recipes and work in the same manner. However many companies use plant-based emulsifiers, which add less fat and cost to production. This also avoids any obstacles that may arise when using egg yolks, such as salmonella. No worries though. As long as eggs are clean and tempered correctly, yolks work perfectly for at home recipes.

However, not all companies use plant-based or artificial emulsifiers. Haagen-Dazs is among the most popular of the all natural brands. Instead of powders, they use eggs to thicken and stabilize their products.  Additionally, the wealthy company controls its own distribution channels and uses specialized refrigerated delivery trucks, which ensure that the ice cream does not melt during transportation.

A few years ago, the Haagen-Dazs also released a new line called “Five”. These specific ice creams only contain five all natural ingredients. Ingredients for the “Five” vanilla bean ice cream include: milk, cream, sugar, eggs, and vanilla bean. Sounds fantastic, except these are the exact same ingredients used in their classic vanilla ice cream.  The ingredients for “Five” chocolate also mirror the classic chocolate recipe (just replace the vanilla with cocoa powder). The same is true for both types of coffee ice cream.

Haagen-Dazs has been using the exact same recipes for years. The only difference is that nowadays, consumers are more concerned with artificial ingredients and often purchase all natural products. Haagen-Dazs cleverly took advantage of this fad, marketing the same ice cream with a new label to attract health conscious buyers. Not a bad idea.

Just like Haagen-Dazs, my vanilla ice cream is made with simple, natural ingredients including egg yolks as an emulsifier.

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The ice cream begins with egg yolks and milk.

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Heat the milk over a medium flame and carefully temper the eggs.

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Then return the custard to the stovetop and heat until it coats the back of a spoon.

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After chilling the custard, put your ice cream machine to work.

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Voila!

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Delicious, natural ice cream!

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Vanilla Ice Cream

2 cups whole milk

2 cups half and half

8 egg yolks

1 cup sugar

Pinch of salt

2 tbsp vanilla extract

Pour the milks into a sauce pan and place over medium heat, stirring occasionally.

Whisk the egg yolks and then slowly add the sugar and salt.  The mixture should be  light in color and thick.

Once the milk is hot, but not boiling, remove it from the heat.  Next, temper the eggs.  Using a ladle, gradually spoon the hot milk into the egg mixture, stirring constantly.  Do so until about 1/3 of the milk is left.  Then pour in the rest of the milk.

Pour the custard back into the sauce pan and heat on a medium flame.  Stir often.  Check for doneness by coating the back of the spoon.  Do not boil.

Immediately place the custard in a bowl and allow to cool.  Add the vanilla extract.  Once cooled, transfer the custard into a sealed container and refrigerate for 4 to 8 hours.

Follow the directions on your ice cream maker to freeze.  Serve immediately, or store ice cream in a container and freeze for later.

Thank you to these websites for all of the information!

Prevent Disease

Ice Cream Science

Ice Cream Geek

Serious Eats

Homemade Hints

Time

Haagen-Dazs

Delish

Food Network

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