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Vanilla Protein Scoop |
Introduction
The typical high-protein frozen dessert has an unfortunate identity crisis – often ending up too icy and with an unpleasant aftertaste of artificial flavor. To combat this structural deficit in formulation, this high protein frozen dessert uses a variety of structural stabilizers in conjunction with just the right fat to protein ratio to yield a smooth and scoopable frozen dessert. A sophisticated flavor of rich Madagascar vanilla bean provides the foreground, while a clean and malty flavor from high quality dairy protein isolates provide the perfect supporting notes in the backbone of the product.
This dessert is well texturized by minimizing the size of the ice crystals within the dessert. Traditional ice cream, are dense, scoopable desserts often made with high levels of sucrose and milk fat, to lower the freezing point of water and to keep the matrix of the dessert soft and not chalky or too brittle. The same can be done with alternative sweeteners and by utilizing a variety of different plant-derived emulsifying gums. This would be a great option for post-training recovery as well as a nutritious and fresh dessert option for the summer and as a basis for a variety of artisanal desserts that can use lower-glycemic mix-ins.
Ingredient Deep-Dive & Smart Substitutions
Whey Protein Isolate vs. Concentrates
Protein powder choice is a major factor in the end rheology of the frozen dessert. Cold-processed cross-flow microfiltered whey protein isolate (WPI) would be a great starting point. Look for brands that clearly state that the product is made with cold-processed cross-flow microfiltered whey protein isolate and specify the protein percentage (90% and above pure protein with very few thickeners is ideal). Because of the delicate nature of WPI it often comes in isolate form. This form of protein dissolves completely into the liquid of the dessert preventing an unwanted sandy-like mouthfeel found in undenatured beta-lactoglobulin (Whey protein) aggregates.
Vegan Adaptation: Use a bio-engineered vegan whey, or a smooth combination of fermentation-based pea and rice proteins. Increase the liquid base by 10% (1.35 oz / 40 ml) to compensate for the higher water holding capacity of the plant based proteins.
Allulose and Erythritol (The Sweetener Blend)
Multi sweetener approach is needed to achieve scoopable consistency in sub zero storage, such as frozen yogurt shops, allulose, a rare monosaccharide, is only 70% as sweet as sucrose but has similar freezing point depression as sucrose, erythritol starts off sweet on the front end but hardens into structures in its pure form and does not remain soft. By combining these two sweeteners, one can achieve scoopable consistency in sub zero storage without hard structures.
- US Customary: 1/3 cup Allulose, 2 tbsp
- Erythritol Metric: 65g Allulose, 24g Erythritol
- Alternative: If allulose is not available, then xylitol may be substituted 1:1 for but it has a slightly greater calorie density.
Unsweetened Ultra-Filtered Milk & Heavy Cream
Ultra-filtered milk is the most concentrated form of native milk casein and whey, stripped of non-digestible lactose sugars. A small amount of heavy cream is added to introduce milk fats which form a slick film on the tongue to interfere with the formation of ice crystals.
- US Customary: 1.5 cups Ultra-filtered milk, 1/4 cup Heavy whipping cream
- Metric: 360 ml Ultra-filtered milk, 60 ml Heavy whipping cream.
- Dairy-Free Option: In place of the ultra-filtered milk use unsweetened cashew milk and in place of the heavy whipping cream use full-fat coconut cream with a minimum of 18% fat.
Hydrocolloid Stabilizers (Xanthan & Guar Gum)
These hydrocolloids in solution bind free water to form the unfrozen phase solution which has increased viscosity and hinders the movement of molecules to form growing ice crystals.
- Measurement: 1/4 tsp (1.2g) Xanthan Gum, 1/4 tsp (1.2g) Guar Gum.
Essential Equipment
High-Shear Immersion Blender: This tool is critical for full hydration of hydrocolloids and for proper dispersion of protein isolates. It can be used to mix ingredients to make a variety of baked goods, but it must be used with extreme care so as not to over mix and thereby shear the proteins, or incorporate too much air into the batter, which can cause it to collapse.
Compression-Decks or Compressor Ice Cream Maker: These machines have an internal part that freezes as the machine is in operation. They remove temperature from the mix very quickly which results in smaller ice crystals in the final product than you would get with a machine that requires you to put mix in pre-frozen bowls.
Digital Scale: A digital scale is essential for the baker. When measuring out baking ingredients and making frozen desserts, the baker needs to know that they are using the correct amount. The difference of a few grams can affect the final product and having a digital scale will enable the baker to be as accurate as possible with their measurements.
Insulated Shallow Ice Cream Tub: A long shallow pan that allows for fast, even temperature penetration for the final tempering of the mixture.
Step-by-Step Professional Method
1. Hydration and Emulsification Phase
In a tall clear container, combine the UF milk, heavy cream, allulose, and erythritol. Insert the immersion blender with the blade fully submerged in the mixture to avoid drawing in air. Whisk on low speed for 30 seconds or until all of the sweeteners have dissolved. Slowly add the whey protein isolate, xanthan gum, and guar gum while continuously blending the mixture.
Visual indicator: It should now look like a translucent white liquid and have an opaque appearance, being glossy in appearance. The fluid should hold together on the back of a spoon and not have any appearance of dry, unhydrated powder in the liquid. It should coat the spoon completely.
2. The Aging and Chilling Phase
Pour the mixture into a sealed glass container and place in the refrigerator at 38°F (3°C) for a minimum of 4 hours; 12 hours is preferred to allow time for full protein hydration and for fat globules to crystallize which in turn will improve the aeration (over run) and stability of the mixture when it is churned.
3. The Churn Sequence
To use your ice cream compressor turn it on first and allow the barrel to chill for about 5 minutes, give the aged flavor base a good stir and pour into the chilled machine.
The Churn Sequence
Churn Starts
The base is completely liquid, glossy, and cold as it enters the pre-chilled barrel.
Micro-Crystallization
The surface begins to mattify, and structural viscosity increases as micro-ice crystals form.
Peak Churn
A perfect soft-serve texture is achieved. The stabilized base holds its shape and clings firmly to the paddle.
Mix will take around 20 to 25 minutes to churn. The finished mix should have a matte finish with obvious ridges visible from the paddle. It should be soft and have a stable form. It should hold its shape when it is scraped with a spatula.
4. Hardening and Tempering
To finish, rapidly transfer the completed churned base to a pre-chilled container, such as a Thermos, use an offset spatula to form an even surface and then press a piece of parchment paper directly onto the surface to prevent sublimation. Place in freezer at 0°F (-18°C) and allow to firm for 30 minutes and then serve
The Science Behind the Recipe
High-protein, low-sugar frozen desserts have a fundamental challenge to their water. The typical use of sucrose in ice cream forms the basis of this challenge because it is a solute that interferes with the water molecules forming a solid crystal of ice. As described previously, this interference to the solidification process of water is called freezing-point depression. However, if there are not sufficient amounts of a solute in the mixture, then the water will form large, undesirable ice crystals and cause the frozen dessert to be too hard and crunchy.
Using allulose in combination with high-protein dairy base depresses the freezing point of the water in the product structurally. The water-binding capability of whey protein isolates holds onto water in the product and prevents it from migrating and joining ice crystals as they grow during the freezing process. The native structures of the ultra-filtered casein and whey proteins in the product go through changes in the cold preparation process but the Maillard reaction does not occur. These native structures of the casein and whey proteins in the product work in conjunction with the xanthan and guar gums to form a viscoelastic network which traps the small air bubbles in the product (overrun) and provides structure to the product without the use of excess fat.
Pro Tips
Pre-Chill the Containment Vessel: Allow your final storage container to become the deepest point in your freezer for a minimum of 2 hours prior to the churning of your ‘base’ (i.e. your ‘stock’ or ‘ingredient mix’). By transferring a hard frozen ‘base’ to a room temperature storage container, the mix immediately begins to melt at the edges, creating an icy outer rim once re-frozen.
The Alcohol Trick: You may have a very cold home freezer, but most freezers don’t get down low enough for the alcohol in spirits to freeze. If you add 1 tablespoon (15 ml) of high-proof vodka or even better, vegetable glycerin to your frozen base before you begin to churn, the areas that do freeze will remain soft and pliable.
Common Mistakes to Avoid
Over-blending the Base: The high frictional heat from using a high-speed blender on the highest setting for long periods can create an unsuitable mixture. By over-blending, too much air can be introduced into the base, causing the whey proteins to foam. When it is then frozen, the resulting texture is commonly described as being ‘chalky’ and ‘spongy’. Mixes should be blended for the shortest possible time, at the lowest speed.
Omitting the Fat Completely: By not using the heavy cream in the formulation you are omitting the lipid matrix from the product. The fat in the heavy cream delays the melting of the product on the palate and in turn carries flavor to the taste buds as it is moved across the mouth. By substituting the heavy cream with skim products the texture of the product will melt directly into water as opposed to having a rich and creamy texture.
Culinary Safety & Hygiene
Care must be taken in the handling of very thick dairy mix to maintain temperature at all times. Make sure that all parts that will come into contact with the base, i.e., the blender shafts, the containers and the paddles in the machines, are first sanitized. The base that is left overnight to age must remain below 40°F (4°C) to prevent uncontrolled growth of bacteria. Once a frozen dessert has melted and been left for more than 15 minutes at room temperature it cannot be re-frozen and returned to sale.
The Perfect Pairing
Pair this dense and creamy high-protein treat with contrasting elements of texture and acidity. A warm raspberry gastrique is a sharp and tangy contrast to the dairy proteins in this treat. A light crumble of toasted almond flour, rolled oats and sea salt adds a further element of nutty flavor without raising the glycemic load of the treat.
Storage & Reheating Excellence
Refrigeration/Freezer Life: The ice cream can be stored in an airtight, insulated container in the refrigerator for up to two weeks. Due to the lack of artificial preservatives in this formula, after two weeks the product will start to slowly lose moisture and form large, undesirable ice crystals.
The Tempering Process: Although this ice cream is formulated to be of a premium nature and to contain a high percentage of fat it does not contain as much fat as typical premium ice cream. For this reason it must be tempered prior to scoop. To temper this ice cream remove the container from the freezer and allow it to temper for 7 to 10 minutes on your kitchen counter. An alternative method would be to place the pint in the microwave on the defrost setting (30% power) and heat for 15 to 20 seconds. This will evenly and quickly soften the matrix.
Frequently Asked Questions (FAQ)
Why is my high-protein frozen treat so icy?
Ice formation in you frozen treats generally forms in free water in the product that has not been linked up by stabilizers and or protein in the mixture. Thus the aged refrigerated base must have the proper amout of fat, and that the measured out quantities of the xanthan and guar gum stabilizers must be accurately used.
Can I use plant-based protein powders instead of whey?
Plant proteins like pea, hemp or brown rice work well too but they absorb loads of liquid – we recommend increasing the base fluid by about 10% and the finished dessert will have a slightly earthy/grainy texture but be smooth otherwise with a slightly different flavor than whey isolate.
Why is allulose necessary instead of using just stevia or monk fruit?
High-intensity sweeteners like stevia and monk fruit sweeten but have no mass. Thus they don’t depress the freezing point of a solution like sugar does. Allulose adds mass to sweeten high-intensity sweeteners thereby enabling a solution to be a scoopable, “frozen” treat.
Nutrition Facts
Some protein isolates work better than others in frozen applications. Have you found some to work better than others and are using them successfully in your frozen products? Also, have you had a chance to experiment with using alternative hydrocolloids such as locust bean gum? I am interested in hearing your technical notes as well as flavor notes and any questions or comments you might have to share with the group. Leave your comments below.
