CUSTARD: When Does It Truly Become… Cream?

Custard or pastry cream is undoubtedly the queen of desserts! It is the perfect complement for countless cakes and pastries—puff pastries, cream puffs, donuts, custard tarts, crostatas, and so much more.

In our article "The Queen of Pastry: The Cream," we discussed how making traditional pastry cream is relatively simple. All it takes is milk, sugar, egg yolks, flour, a pinch of flavorings, and then everything goes into a saucepan to boil—gradually transforming before your eyes into a luscious cream.


BUT WHY DOES THE CREAM… BECOME CREAM?

In hot pastry cream, what we’re really doing is cooking flour or starch in milk.

As the mixture heats, the starch granules in the flour (or native starch) begin to gelatinize. In the presence of milk or another liquid, these granules hydrate and break down, losing their crystalline structure. Amylose and amylopectin—the two main components of starch—are released, forming bonds with the water molecules in the liquid. This creates a starch gel with binding and thickening properties. This gel then integrates with the other ingredients to form the creamy texture we call pastry cream.

This transformation is not a chemical reaction but a physical process induced by heat.

THE ROLE OF OTHER INGREDIENTS

  • Egg yolks: They play a crucial role in thickening the cream, giving it structure and consistency.
  • Sugar and milk: While milk can technically be replaced with water, it, along with sugar and flavorings, enriches the cream’s flavor profile, creating the delicious dessert we know and love.

To avoid lumps, it’s essential to:

  • Add milk to the mixture below the gelatinization temperature of starch (which ranges from 50°C to 70°C depending on the type of starch).
  • Stir continuously until the starch is fully gelatinized.

Pouring starch into hot milk often leads to clumps. This happens because the starch does not disperse evenly in the liquid, and the surface of these clumps gelatinizes quickly, creating a gel that prevents the liquid from reaching the starch granules inside.

TOOLS FOR PERFECT PASTRY CREAM

In professional kitchens, a cream cooker (cuocicrema) is often used. This device stirs and cooks the ingredients while controlling temperature and timing. At home, with practice, you can achieve the same result with a saucepan and whisk!

For added convenience, you can also use our Traditional Hot Pastry Cream Mix (click here).


PASTRY CREAM MADE… COLD?

While traditional pastry chefs often guard their recipes, it's also possible to create a smooth, delicate cream without heating milk or spending time over a stove. How?

By using our Quick Pastry Cream Mix, which only requires a bit of milk or water and a quick stir—ready in one minute!

The development of quick pastry cream stemmed from the need for a stable, long-lasting cream without eggs, while maintaining the quality of traditional pastry cream.

This is achieved with modified starches instead of flour or native starches.

Modified starch gelatinizes at room temperature, requiring no heat. Ingredients like calcium alginate (a natural thickener) replace egg yolks, and potassium sorbate extends shelf life.

SIMPLE PREPARATION for an easy pastry cream with our Quick Pastry Cream Mix (click here).

  • Dissolve 100g of Quick Pastry Cream Mix in 280g of milk or water (or 260g if using water).
  • Stir, and your cream is ready!

As mentioned earlier, the primary ingredients used in quick pastry cream include:

  • Modified starch: What is modified starch? It provides thickening properties at room temperature. It is not genetically altered but physically, chemically, or enzymatically processed to change its properties.
    • Physical modification: Pre-heating.
    • Chemical modification: Treatment with alkalis (like sodium hydroxide) or inorganic acids.
    • Enzymatic modification: Partial hydrolysis to improve solubility.
  • Potassium Sorbate (E202): A preservative derived from mountain ash berries, it prevents microbial spoilage.
  • Calcium Alginate (E404): A natural polysaccharide from brown algae used as a gelling agent.