i mean if you have the cash to blow, a blast chiller is pretty useful in cooking. it’s not going to really guarantee food safety or quality, really, beyond what a dip in an ice bath does, then tossing it in the fridge.
i took a look at the chefsteps recipe for lemon curd, if that’s what you used. an hour at 75C is actually quite a high combo when it comes to whether something is pasteurized, so i wouldn’t worry about it. especially for something like a cure, where you’re going to get easy heat transfer since it’s mostly liquid.
one thing to keep in mind is that if you do look at pasteurization curves (it’s always temp and time, not just one or the other, as you can pasteurize something at lower temps (within reason) by doing it for longer) is that the timing starts once you’ve reached the temperature in the deepest part of whatever it is you’re cooking.
this isn’t a huge problem for something like an egg, say, but can come into play when doing big cuts of meat.
