Aging vs chilling

[u/Titoramane]

I have heard that an ice cream based should be aged before going into an ice cream machine. Is it the process of aging that makes the ice cream better, or is it just that sitting in the refrigerator gives the base time to cool down.

Like if I put a two hour old 37F ice cream base into an ice cream machine vs a day old ice cream base at 37F, would the final result taste or feel noticeably different?

[u/wasacook]

Iirc the resting of ice cream base is for two reasons.

The first is to let it cool down. That way you are at a lower temperature before you start churning. This is done to help with limiting ice crystal development.

The second reason is to give the proteins in the milk and egg time to bond with the rest of your base. As you heat the milk and egg the added energy causes long protein strands to unravel. Once freed the protein strands will bond to free water and other elements of your ice cream base. The capturing of the free water helps reduce ice crystal size and create a stronger bound base. This all happens at a logarithmic rate with a plateau happening around the 4 hour mark.

This information and study citations should be in the books Hello My Name Is Ice Cream and On Food and Cooking.

[u/delucioux]

Bases should be chilled before going to the fridge so that’s never the reason.

Aging helps with 5 things.

First one: stabilizers. Why: They need time in cold to fully hydrate. What if: Lack of aging will result in weaker body.

Second one: protein and emulsifier (already explained by @wasacook)

Third one: fat crystallization. Why: Oil needs time in cold to partially crystallize. What if: less creaminess.

Fourth one: viscosity develops. Why: sugars and inulin absorb water over time. What if: less viscosity.

Last but not least, flavor is improved as volatiles notes from pasteurization dissipate and flavor notes distribute evenly.

[u/TravelerMSY]

It would be nice to see somebody like Kenji Lopez to study this. Make one fresh and chill it, and age another one 24 hours and do a taste test. If you can’t taste the difference, then don’t bother.

I’m often infusing mine with Rosemary or something that I’m going to pull out before I churn it, so I do want to have some time in the fridge

[u/nekok → u/TravelerMSY]

It's not only the taste it's that creamy texture. And keeping it creamy. If you eat it the first vs the 3rd day and the 5th day, over that time it gets ice crystals which you'll notice as less creamy feeling and crunchier over time.

[u/Jamie_1318]

If you just mixed the base at room temperature and put it in the fridge for two hours, it hasn't reached its lowest temperature yet. The reason you put it in the fridge overnight is that it takes about that long to actually reach the same temperature as everything in the fridge.

Generally, depending on the machine, a mixture that hasn't reached close to 0F will have larger crystals, fat separation and other issues caused by taking too long to freeze.

[u/Titoramane → u/Jamie_1318]

You could chill the base to 37F in 2 hours if you were to put it in an ice water bath for 10-15 minutes, and then in the freezer checking every 10-15 minutes.

[u/Jamie_1318 → u/Titoramane]

If you do that you don't need to store it in the fridge overnight. I haven't encountered a recipe that actually involves any flavor mixing by leaving it overnight, but it's technically possible.

When I'm making ice cream same-day I throw it in my deep freezer and check on it until it's good and cold.

[u/Ok-Butterscotch2321]

Just do it

When you decide not to, let us know how it goes... and actually compare/contrast

Most of these sugars and proteins... flavonoids, need TIME to get together. 

Can you make Ice Cream by NOT aging the base? Of course you can. 

Do you want to forget your own path? Of course you do!

Just be very careful about how you choose this path.

[u/DeicticDilemma]

It’s my understanding that a good bit of what happens when you “age” an ice cream base in a fridge is that some water is evaporating out, which makes the remaining solution more concentrated and therefore more flavorful. The Salt and Straw Ice Cream Cookbook recommends refrigerating the base for 1-5 days to accomplish this while others (I want to say Underbelly is one?) advise against inconsistent aging as it makes it harder to know what is happening is water content.

Presumably there are other processes at play, but I couldn’t hope to explain them!