No matter what equipment you have in your kitchen or how perfectly creamy you prefer your soups, here are some tips to help you puree your next soup.
1. Choose Your Equipment - When it comes time to puree a soup, our main choices are a blender, a food processor, or an immersion blender. Each has their pros and cons:
• Blenders - Blenders do a great job of pureeing soups. The only difficulty comes from transferring the hot soup to and from the blender itself, an annoying, messy, and potentially hazardous process. Blenders will also occasionally leave small chunks of soup unprocessed, especially older blenders.
• Food Processors - Food processors tend to chop up the soup into small pieces rather than actually pureeing it, leaving the soup with a slightly gritty texture and non-uniform pieces. Some of this can be helped with the tips below, but I've found that a truly silky puree is a little beyond the reach of most food processors.
• Immersion Blenders - If perfect creaminess is your aim, an immersion blender is a must-have item. I resisted its lure for years before finally giving in, and I haven't regretted it for a moment. There's no mess of transferring the soup; all the pureeing is done right in the pot. And the immersion blender mashes even the tiniest particles into oblivion. This is my new best friend when it comes to pureed soups.
• Other Equipment - In a pinch, you can use a potato masher to puree your soup or press the entire batch of soup through a strainer (or tamis). Both methods will require some muscle work, but will get the job done!
2. Soft But Not Mushy - Don't rush the cooking process and try to puree the soup while the vegetables are still hard or your soup will end up tasting gritty. You want the vegetables soft all the way through, but not so cooked that they fall apart into mush.
3. Adding Cream and/or Oil - Many recipes have you stir in the cream or last few tablespoons of oil once the pureed soup is back in the pot. Instead, try streaming some or all of it into the soup as it purees. This makes a better emulsion and gives the soup a creamier feeling in your mouth.
4. Add a Slice of Bread - This is one of those bits of kitchen magic that has to be tried to be believed. Add a slice of bread, torn into big pieces, to the blender or food processor along with the soup, and somehow this helps to make a more uniform puree with fewer chunks left behind. I usually do 1/2 - 1 piece of bread with each batch being pureed. (Added bonus, you won't need to add as much cream later on!)
5. Pass the Soup Through a Strainer - Set a strainer over your soup pot and let the soup drip through after its been pureed. This separates out any big chunks left behind by blender or food processor, which can then be re-blended. A plastic scraper will help push the soup through the strainer more quickly.
What other tips do you have for making perfectly pureed soups?
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Another tip: use sachets for herbs and remove prior to blending. You can either use a tea ball or fillable, disposable teabags (available at most Japanese stores).
I'm curious to know why you wouldn't want to puree vegetables cooked until they fall apart? I would think that would be a good thing if you're going for smooth soup.
I agree with @vintagejenta. Pureed vegetables actually help thicken my soups--a smoother, nicer texture than mushy veggies. I also use an immersion blender like this simple one and yes, best to use a cast iron pot or something that won't scratch.
I love our immersion blender, it is a genius invention and works so much better than other options. Plus it is much easier for baby food purees, if you make them.
What about the several excellent non-electric options out there? I love my immersion blender, but it does not yield the smoothest possible result. For that, you need to push it through a food mill or sieve. <3 my food mill, and we use it allll the time.
Though I've never tried it, several of my favorite cookbooks recommend a Chinoise or "China Hat" strainer for the silkiest of soups.
@vintagejenta I think they are saying that you shouldn't rush to puree before the vegetables are fully cooked, and also not to overcook to the point where they become total mush.
@MaryWinn : see the 'Other quipment section'.
And it's actually called a 'chinois'. :)
I find I have total the total opposite results in terms of smoothness with my immersion blender (its a nice Kitchenaid one) I adore it, but no matter what, I always have a slight bit of non-smoothness when I use it no matter how long/speed/doneness of the soup. Its an annoying step to me now that I have my immersion blender, but a regular blender always gives me a smooth as silk result.
Food mills are another good option and preferred by a lot of people because they inherently filter out any tough or woody bits from your soup, which any of the other methods would leave in the soup. Personally, I use an immersion blender, but I would like to have a food mill someday.
(Oops! MaryWynn, I didn't see that you had already mentioned the food mill)
@Christine M. - not sure why you felt compelled to call me out. I’m just trying to add something to the discussion. I did read the whole post, which mainly suggests removing and re-blending solids and nowhere mentions a food mill (hi @misplacedtexan! Food mills are awesome).
http://en.wikipedia.org/wiki/Chinoise I’m a terrible speller, but I didn’t get that one wrong. And it’s MaryWynn - with a Y.