On Saturday, I had baked a honey ginger sponge cake. As a recipe with no added fat (the only non-negligible fat being from egg yolks), the cake is somewhat dry. So, I usually serve it with whipped cream and berries. Quite good, when it turns out right (about 10-20% of the time, it somehow separates and a weird rubbery eggy layer forms on the bottom).
So, I went to the ‘fridge and pulled out a half pint (why don’t they just call it a cup?) of cream and put it in the mixer – as I’ve done many times – with some powdered sugar and vanilla extract. Five minutes later, I had aerated cream. Ten minutes later, I had aerated cream. Why wouldn’t my cream whip!?
I scoured the internet. Yes, I had bought cream, not whole milk. Yes, I had chilled the bowl. Yes, I even tried sprinkling gelatin and making sure the mixer was oriented along a magnetic field line but not anti-parallel to the nearest lay line. Okay, not that last bit.
This is where I encountered some of the oddest pseudoscience in awhile, people trying to give advice or reasons why cream wouldn’t whip up. Among them were:
- I should add a touch of lemon extract (an acid) to help break down bonds.
- Add cream of tartar.
- Add gelatin.
- Use a copper bowl instead of stainless steel.
- You can’t use Pasteurized – and especially not ultra pasteurized – cream.
- Could be that the cows had an off-week.
- You have to start the mixer at a low speed.
- You can’t add the sugar at the beginning, you have to add it after it’s started to get fluffy.
- You have to add sugar at the beginning (“it wont whip on it’s own”).
- The bowl wasn’t cold enough (“They must be super cold.”).
- You have to use the whisk attachment, not the egg beaters attachment.
- Cream that had been frozen won’t whip.
I can, with practically 100% certainty, say that all of those are bulls–t. The real reason why my cream wouldn’t whip? I accidentally bought Table Cream instead of Whipping or Heavy Cream, meaning the butterfat content was 18% instead of 30-38%.
There is a very basic physics to this: Whipped cream is a fat-stabilized foam, meaning that you have to beat tiny air bubbles into the fat matrix of the cream. If there is not enough fat, then they cannot support the air, and the air will simply diffuse out. If there is enough fat, then they can trap the air. The one bit in the above list that was sort of correct is that colder fat will hold the air a little better (they’re somewhat stickier), so it does help a bit if your cream is just above freezing and you use a cold bowl to keep it colder longer. However, that is far from necessary. And, cream of tartar is a general stabilizer in whipped things, so that could help, but it is not a fat substitute — you still need to be able to whip the cream to begin with, the cream of tartar will just help keep it whipped once you’re done.
Everything else in that list is wrong. Acids can denature fats and so it can actually PREVENT the cream from whipping. Gelatin could work if you do it right — it has to be dissolved first in the liquid, and if you add it directly to the whipping cream, you’ll just get granules of gelatin. Pasteurization has nothing to do with changing the structure of the fat, same with the cows having an off-week or the cream having been frozen at some point in the past. The mixer starting at low speed just means it won’t splash as much and it will take longer. The two sugar claims are contradictory, and it doesn’t matter how you get the air in so long as it’s tiny air bubbles.
I guess I shouldn’t be surprised that pseudoscience crops up everywhere. But, I was amazed at the amount of it for something so simple as whipping cream, and that only on one site out of the dozen that I looked at did someone suggest ensuring that the cream was 30-38% butterfat, and that even if it says “cream” on the container, it can be below that and won’t whip.