I recently got into debate with a friend over, of all things, how to make risotto. I was taught that warming the broth before adding it to the rice was absolutely crucial for a making an excellent risotto, but my friend said she doesn't bother with this step and gets fine results. When she pressed me to explain why warm broth was important, I realized that I didn't actually know. Point, scored. Research would be required.
I consulted several sources, from my culinary school notes to the recently released tome The Fundamentals Techniques of Classic Italian Cuisine. The best explanation I found is that cooking is improved and proceeds more swiftly if all the risotto ingredients are the same temperature. Essentially, adding cold broth to a hot pan of cooking rice will cool everything down, whereas keeping a constant cooking temperature keeps everything moving along at the right pace.
This answer feels a little unsatisfactory to me. Risotto is usually cooked in a wide pot and the broth is being added in incremental cups—the relatively small dip in temperature from this relatively small amount of broth spread over the surface of the pot just can't make that huge of a difference. Maybe it does in the precise and demanding environment of a restaurant kitchen, but when we're just making risotto for ourselves in a home kitchen? In this case, I'm inclined to think that warm broth is of less vital importance.
What do you think? How do you make risotto?
Related: How to Make Great Risotto at Home
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Here's my take on it whether you like it or not.
I say that warmed liquid is crucial. Having said that and ignoring the broth argument, I want to start at the wine you add after toasting your grains. I think that the wine should be cold when its added to the pot because you save a lot of the character of the wine if it's cold. Chemically, wine is very different from stock (sugar content vs. protein content) and the two shouldn't really be compared. If the wine's warm, it's more prone to oxidation and you'd basically be adding a "funk" to the riso, granted it doesn't cook out.
On the hot and cold stock story, I firmly state that warmed stock makes a difference. Let`s think of a 5-day old baguette as one little grain of arborio rice. If you take the baguette an roll it in a bit of flour, you have a rough model of what a rice grain is like. if you take the baguette and put it in cold water, you`ll eventually soak it through but you get a gummy mess of the flour on the outside. This is basically what`s happening with the rice when you `shock` it with cold broth (Yes, I'm aware it comes to cooking temperature eventually). What you want to do is easily take the flour off and encourage proper cooking of the grain, which is accomplished with hot water. With warmed stock, a gummy mess ensues but it is mostly brought outside of the grain (allowing for easier cooking) and the mess contributes to the starchy-goodness texture of the riso.
But your friend says that there's no big difference... that's subjective though, right? Her palate vs. yours?
I warm the stock, but I never knew the reason why - thanks, @Oreo-belt. I also use warmed milk for mashed potatoes, but then I like mine runny.
The reason for the warm broth is very simple: every time that you pour something cold on the cooking rice you stop briefly the cooking process (that's happen not just for rice, eggs too).
Now, when you cook risotto you pour broth on the rice every few minutes, so if the broth is cold, you stop the cooking every few minutes too. The cooking process starts again short afterwards when the temperature in the pan rises again. This continuous changing in temperature stresses the surface of the grain and breaks it. The grain absorb more water and, more importantly, loses consistence.
If you are used to eat overcooked pasta and rice or if you use rice that is not crystalline (not high quality) you won't probably notice the difference but maybe your guests would.
America's Test Kitchen made a bunch of risottos and proved that a lot of the traditional steps which you're told must be done a specific way are not really required. Risotto is like macarons in that there is a lot of mystery and tradition surrounding it which is done because people swear it won't work otherwise, when it usually will. Their conclusions (can't link, behind a paywall):
After extensive testing, we learned that traditional risotto recipes are not sacred and can be simplified. For example, while Arborio is the preferred rice, other japonica-type varieties, such as Japanese short-grain rice and California-grown medium-grain rice, can be used in a risotto recipe. Also, the traditional method calls for hot liquid to be added to the rice about half a cup at a time. This requires constant stirring to keep the fairly dry rice from scorching. To save work, we found that we prefer a deluge-then-stir method that starts out with a lot of liquid. When the pot dries out, the remaining liquid is added in small increments.
That said, I do like doing it the more traditional way, in smaller increments, because I like the involvement it entails.
I make risotto on an almost weekly basis (in fact, I did last night)....and I do not warm the broth/stock. I always have a carton on stock in my fridge and there's usually 1/2 cup or so in there....and the remainder is from a new carton from my pantry, so it's at room temperature. I've made it before with warm stock and my husband and I haven't noticed a difference between the two ways.
I always like the way warming the broth becomes part of the process. I make the broth, and then leave it simmering on the stove, and set up my risotto pan next to it. I strain the broth as I pour it into the risotto. I think it's part of the pleasure of making a risotto!
@Imkm: I love shortcuts, and for me no recipe is sacred so thanks for that! It's like when people say always make fried rice with cold or refrigerated rice, I want to scream "Noooo!" Just because it's a dish that traditionally uses leftovers doesn't mean that it HAS to be made with leftover rice. In fact, it makes less sense as cold rice is so much harder to manipulate.
Greetings from Italy, near Milano and Piemonte, so the places where risotto has been crea ted. I nave been eating risotto for fourty years and cooking it at least for fifteen. First of all, no one here use Arborio. The only rice that can be used to cook risotto is Carnaroli. This make a super huge difference. Much much more than quite anything else. Wine? Cold. Broth? Hot. Does it makes huge difference? I don't really know. It's not a matter of tradition, the reason is simpler. We make broth when we make risotto. So it is hot when it's ready to be used.
What make big difference then, is the Time of cooking (no more than 20 minutes) and what we call mantecatura (sorry, don't know if exists the translation): light off the fire, put in the butter, parmigiano reggiano grated (shredded?) and gently blend with a wooden spoon until you see it's ready. Depending on the recipe, mantecatura could be done adding something else.
Hm. In all honesty, I use the lazy way... I thaw my homemade broth (that I keep in the freezer) in the microwave, so I guess it's lukewarm when it goes in.
What I do make sure I do is to add the butter and the parmigiano reggiano and mix a little at the end.
If you're making butternut squash risotto (and that's what I'm making most of the time in the fall and winter), how else would you infuse the broth with saffron but to warm them up together?
Am I the only person who uses saffron?
@SchoolieJoolie, of course not! In Italy risotto with saffron is named "alla milanese". It's the one i make more often. A variation which is a typical dish of my town In carnival time, named "con la luganiga", is with saffron and sausage. My personal variation instead ( of saffron risotto) is to add camembert cream during mantecatura. Another one (of my personal variations) which i like very much is a simple standard risotto, without additional ingredients, just during mantecatura i add camembert cream and truffle cream
adding cold broth shocks the grains, making them hold onto their starches. releasing their starches is essential for that creaminess, thus warm broth. its kind of like making felt, warmth and aggravation is necessary. i use room temperature wine and will, if using dried porcini mushrooms, rehydrate them in the wine prior to get extra mushroom flavor.