For home cooks that are just looking to make dinner, and not restaurant-quantity stock: bigger is not better. We recommend getting the smallest pressure cooker to fit your needs because a bigger the pressure cooker will take longer to reach pressure, will need more liquid to get there and it will be bulky to both clean and store.
More material. A larger pressure cooker will have more metal and that metal will take more time to heat up – time you’ll be waiting for it to reach pressure.
More liquid. As pressure cooker size increases so do the minimum liquid requirements – while a small 2qt pressure pan only needs about 1/2 cup of liquid (or less) to reach pressure a much larger 12qt pressure cooker needs two cups (or more)! The same piece of meat that braises in the smaller pressure cooker can only be boiled in the larger one – limiting the cooking techniques that can be achieved.
More work. On the more practical side of things, a giant pressure cooker is going to be tricky to wash and store. Depending on your sink and water tap configuration it can be quite a challenge to wash. Instead, a 6-quart cooker with a dishwasher safe base can easily slip into the bottom rack.
Start with a 6 -8 quart/liter standard stockpot-type pressure cooker. Most recipes found online and cookbooks are designed for this size cooker.If your main goal is stock-making but for a family – not a restaurant – keep in mind that a typical 6 quart pressure cooker can produce 4 quarts of double-strength stock (here’s how) – diluted that’s 8 quarts of single strength stock!
The size and shape of standard pressure cookers are very versatile allowing the cook to try new and advanced techniques that take advantage of this cooker’s height – such as bain marie, dupleX (and triplex) cooking, and steaming.
Choose your pressure cooker’s size carefully and to match both the pressure cooker size and shape to the kind of cooking you’re most likely to do with it.
And, don’t forget, that the easier the pressure cooker will be to use and clean – the more likely you’ll be to use it!