A physicist's guide to ice cream

I started cooking ice cream this summer. I bought an ice cream machine that can yield 1L of ice cream in 30 minutes, and prepared about 30L, sometimes sourcing material from the garden (strawberries, raspberries, cherries, figs and blackberries). If you enjoy the taste of fresh figs (which I don&#x27;t normally because of the texture of the fruit) it is an incredible way to preserve it.<p>The best ice cream I made was blueberry + coco cream + lime. Highly recommend it. Coco cream as a substitute for water in sorbet is an amazing trick.<p>Shared this with a friend yesterday:<p><pre><code> 1. **Creaminess (smooth, creamy texture)** Creaminess ↑ ⇔ Cream ↑ + Eggs ↑ + Sugar ↑ Creaminess ↓ ⇔ Water ↑ + Fresh fruits (high in water) ↑ 2. **Lightness (airy texture)** Lightness ↑ ⇔ Milk ↓ + Cream ↓ + Eggs ↓ + Sugar ↓ Lightness ↑ ⇔ Air incorporation (whipping) ↑ 3. **Stability (avoiding crystallization)** Stability ↑ ⇔ Sugar ↑ + Eggs (yolks) ↑ + Alcohol ↑ Stability ↓ ⇔ Water ↑ + Uneven freezing temperature ↑ 4. **Density (weight in the mouth)** Density ↑ ⇔ Fats (cream, butter) ↑ + Eggs ↑ + Sugar ↑ Density ↓ ⇔ Incorporated air ↑ + Water ↑ 5. **Melting Temperature (softer or harder out of the freezer)** Melting Temperature ↑ (softer) ⇔ Sugar ↑ + Alcohol ↑ + Air ↑ Melting Temperature ↓ (harder) ⇔ Water ↑ + Freezing temperature ↓ 6. **Sweetness (perceived sugar)** Sweetness ↑ ⇔ Sugar ↑ + Sweet fruit puree ↑ Sweetness ↓ ⇔ Acidity (lemon, vinegar) ↑ + Acidic fruits ↑ 7. **Crystallization (grainy or smooth texture)** Crystallization ↑ ⇔ Water ↑ + Poorly mixed ingredients ↑ Crystallization ↓ ⇔ Fats ↑ + Sugar ↑ + Proper agitation ↑</code></pre>

The best ice cream recipe ever I got from a physicist:<p>Cream + sugar + vanilla, stir until dissolved. Slowly add liquid nitrogen while stirring fervently until sufficiently frozen.<p>The stirring in of the liquid nitrogen not only freezes the cream, it prevents any cristallisation and fluffs up the ice cream by evaporating. Truly delicious!

I started making my grandmother&#x27;s recipe again recently and it&#x27;s amazing and amazingly simple. A pint of cream, a tin of condensed milk and a teaspoon of vanilla extract. Whip the cream until it lightly peaks, stir in the condensed milk and the vanilla and freeze for at least 4 hours. Done. You can add choc chips or whatever flavor you want at the condensed milk stage.

Last summer I experimented making ice cream without ice cream machine. The principle I used was to freeze it in plastic bags, take them out once or twice to &quot;massage them&quot; and then to squeeze them out into a frozen bowl where they rest in the freezer until eating time.<p>The recipes are important too of course. The sugars need to be a mixture of fructose and dextrose. Also used a stabilising agent. But eventually I could create really good ice cream with a minimum of equipment.

The basic Ben&amp; Jerry&#x27;s recipe in an ice cream machine is pretty much unbeatable if you&#x27;re looking for traditional ice cream. On the other hand, I&#x27;ve tried, without much luck, lower calorie ice creams using substitute sugars like allulose. Unfortunately, they haven&#x27;t turned out very well. It really is the combination of real sugar, fat, protein, and all that that comes together in the cold to make the magic happen.

My local supermarket only sells the basic flavors vanilla, strawberry and chocolate. But then they sell dozens of variants of Ben and Jerry&#x27;s and similar brands. I wish this was the other way around. Just give me boxes of single flavors like in the Italian gelaterias.<p>I guess supermarkets get higher margins on B&amp;J&#x27;s :(

my view of ice cream has changed over time. I grew up close to the biggest factory for ice cream in the UK where it was adjacent to the biggest bacon factory in the UK.<p>The myth at the time was that the fat from the bacon went next door to the ice cream factory. At the time the label just said &#x27;animal fats&#x27; rather than &#x27;dairy&#x27; so there was nothing to dispel the myth.<p>Since then the formulation has changed, now you get the usual palm oil. As far as ultra-processed foods go, is there anything worse than commercial ice cream? You have got animal fats or palm oil to block your arteries, refined sugar to spike your glucose and lots of emulsifiers and other &#x27;e numbers&#x27; to disrupt your digestive tract?<p>Most ice cream is sold in tourist venues where the vendor knows he will never see the customer ever again. There is zero motivation to make it a healthy product or to use quality ingredients when you are not expecting repeat customers.<p>In other developments, there is a move to have more efficient freezers for ice cream in stores, which means changing the temperature so it does not need to be stored at such a low temperature. The likes of Unilever can spend a fortune on the food science to get the temperature up, to roll out new freezers.

History of Ice Cream is starting to sound realer by the day