I’ve experimented with a slow stock this week (I’ve just finished a 3-day beef stock). The process is an interesting one; water is kept at barely a simmer and is reduced until more water is needed and the cycle continues. As part of my experiment, I wanted to see just how low the heat could be to constitute a ‘slow simmer’
The photo above shows my pot of stock after losing 4 liters (quarts) of water in 12 hours. The ‘scales’ on the side include some fat residue and a lot of dried tomato skins which I use in lieu of tomato paste.
How slow was the simmer that reduced this pot by half? It was hardly bubbling at all; a bubble may come to the surface every few minutes.
Water can never get above 212 degrees Fahrenheit (without pressure). At 212 degrees it changes state into a gas at which point it produces bubbles (and you see steam). A rolling pot of water is no hotter than one at it’s slowest simmer.
A full boil would have reduced this pot faster (I imagine this is due to the different temperatures in the pot – I suspect the stock nearest the element was hovering at 212 and cooling by 1-2 degrees as it rose through the pot) but the water would have barely been any warmer than it was. It would have also moved the ingredients around rapidly which could produce more sediment and emulsify the fat into the water (making it harder to remove).
This low temperature is a little ridiculous (although it allowed me to leave the pot without close monitoring for longer periods of time) but it’s often beneficial to cook ingredients at a very gentle simmer as it offers all the same heat benefits without circulating the ingredients into mush. An ideal slow simmer has a constant but very gentle stream of small bubbles.
Do you agree or do you think differently?
What I want to know is if the flavor is any better, and how much better? Is it worth the three days’ worth of gas/electricity, used burner real estate, and concern of house fire?!
Christine,
Thanks for the comment!
I really did this to learn about simmering; not so much stock. Unless I was making a veal-bone stock, I wouldn’t make a 3-day version (though I often will make a 12 hour one).
At the temperature it’s running, I’m not worried about the risk of fire and, since we’re cooking for 2, the burner real estate isn’t a big deal. Electricity could be but it would be interesting comparing a full boil for 3 hours to this low heat for 12.
The biggest difference is the clarity. The full boil will damage foods as well as incorporate any fats into your broth and make it cloudy.
Not sure if that helps?
Just for clarity?! Personally, I won’t go to great lengths just to have a clearer stock. I am lucky enough to have all grass-fed beef and pasture-raised chickens from local sources, so I actually value the fat incorporating into the stock… I’m a big proponent of eating lots of healthy fat! There would have to be a substantial flavor improvement or nutritional advantage to the slow simmer for me to commit to anything over 24 hours. Aesthetics aren’t a priority. From your replies in the comments, it sounds like clarity was the main advantage for a slow simmer… so probably not for me!
I did go back and read your tip on the burnt onion– can’t wait to try that one with the next batches of stock!!
Fair points Christine and personal preference is the most important reason to do any of this of course. I remove the fat because I’m not a fan of the layer of fat on top of a soup – but I don’t toss it. It’s put in a jar and I cook it down separately and use it like tallow. Most of my beef broth is simmered 8-12 hours and chicken is 4-6 hours.
But I think I’ve explained myself poorly – the timing isn’t really the issue. Whether you cook your stock at a full boil or a slow simmer, the temperature of the water is the same. It can’t get over 212. So if you want a clearer stock than you have now, you don’t need to change your time at all; a hard boil isn’t required. This isn’t just for stock but includes cooking more delicate things like homemade pasta and even gentle vegetables. Not sure if that explains it any better or if I’m conufsing the issue further?
Most really long stocks I believe (though am not certain) are cooked that long to help pull the most gelatin as possible out of the bones. I know some restaurants that do 3+ day stocks as a way of minimizing their waste – they add peels and trimming as they go.
Agree totally. I do a very low simmer to keep little bits from coming loose and swirling around in the water. It comes out as a much nicer stock.
Thanks for the comment Diana! What types of stocks do you make?
Joel
We make chicken broth every week, you would too if you raised your own chickens appleofmypie.ca. I wonder if we have been getting maximum flavour. Based on the experiment here what’s the best compromise between length of boil, temp, etc?
Most of the recipes I’ve seen call for around 2 hours at a slow simmer. In your opinion is there a flavour benefit to a longer, lower simmer?
Hi Mike!
I so agree that I would if I raised my own chickens. Our fish broth simmers for about 45 minutes. Chicken tends to go 4-6 hours, beef is 8-12 (or more). That’s just a guideline but the second half makes a huge difference.
If I’m making beef stock, I’ll often char an onion (as in BURN) in a cast iron pan to add flavor and colour. If I’m making chicken stock, I cut the onion in half but keep the skin on. This will add depth of flavor and color. A small herb sack can make quite the difference too.
As long as your simmer isn’t rapid, it allows you to pull the fat and/or scum off the top. I don’t think there’s a major difference – in both cases the water would be nearly identical in temperature since both are boiling.
Hey Joel! I taught a class last week on using the whole chicken and one aspect we covered was making stock from the bones and trimmings. We made a quick stock in class but the stock that really got the attention (and gobbled up) was the one I made at home and brought- roasted bones with bits of meat, roasted veg (carrot, celariac, onion), bay leaf, peppercorns, parsley stems, slow simmered for a couple of days. After it was strained and degreased it was exceedingly tasty and would have been great put up as is. But I wanted to show my students stock taken over the top so I clarified it with a raft. It was a thing of beauty- a sparkling jug full of jelly when cold; golden, transparent and flavorful when hot. Would I do the clarifying bit every time I make stock? Pfffft, no! But a slow 2-3 day simmer is definitely superior to a quick stock when it comes to flavor and richness.
BTW, we also made schmaltz! I used the rendered fat for a skillet of cornbread and (I can’t believe I’m saying this) I think it tasted better than with bacon fat!
Rebecca,
I ADORE YOU!!!! Really love that you did that, compared the two and your candid admission about it being better than bacon fat!
By ‘clarifying it with a raft’ do you simply mean chilled it to get the fat floating or am I missing something?
I wish we were closer – I’d be signing up for class.
Joel, do you char the skin on onion for chicken stock as well? Are you talking oven roasting to a char?
Rebecca, roasting the bones makes a big difference?
I’m very seriously considering a pressure canner now. I think it would be a huge leap forward in my goal of having ready made meals. Aside from broth, meat sauces, chicken soup, and so many more canned meal ideas…..
Hi Mike!
I char them in a cast iron pan for beef stock. It would work for chicken but chicken stock is often lighter. Here’s a post on the technique (you could use a single onion): http://wellpreserved.ca/the-secret-to-darker-stock/
We have a bunch of pressure canning articles (separate from recipes) that may help – including advice on buying one. Scroll to the bottom of our preserving index here: http://wellpreserved.ca/find-stuff/site-map-3/preserving/
Let us know if you do go with one – we love ours (I’m canning 5 quarts of beef stock that were given to me yesterday right now). A lot of our use for it stems from the fact that we have no room for a large freezer.
Hi Mike, I think roasting the bones and veg (or just the veg in the case of vegetable stock) makes a deeper richer tasting product. Not roasting and long slow simmering ends with a lighter but still fully flavored stock. Both have their place, I just happen to prefer the roasted stock. I also like the bit of acidity a healthy splash of white wine adds to chicken stock. Forgot to mention that.
Rebecca,
Great tips all around – especially about the acidity. I find that most hope cooks miss adding acid to dishes; many of my chef friends won’t serve a single course without a touch of acid (wine, vinegar or other)….
We do stock about once a week like Mike above. I don’t raise chickens (though we’re starting Quail in the spring!), but just get the most bang for our buck by buying whole birds. It’s an all day process for me, around 8 hours or more depending on when I get going in the morning. I’ve also started leaving the skin on the onion (I add it around the midway point. I don’t know why I add it then and not at the beginning, other than that a german grandma told me to when I was 6 and I never forgot it) and I really love the colour the stock gets. My son discovered a container of it in the fridge the other day and never realized before that, cold, the stock has a consistancy of jelly. Or, as he assumed, Jello. There was a very disappointed ten year old in my house that day.
I never really thought about the roiling boil/simmer. I default to simmer unless I have a good reason for wanting the boil (canning/jamming mostly). My son has recently gotten interested in what I’m doing in the kitchen and learning himself, and this is a good post for decluttering my own reasons behind why I’m doing what I’m doing. Thank you
Heather, I love this comment! I have such a soft spot for ‘person history’ things like the cooking secrets we learned at 6 years old and become truth. I also chuckled at the idea of chicken-flavor jello!
It has to be awesome to have a little helper’ especially one that helps you debunk your own kitchen mysteries!
Great discussion. I make stock every few days, often for the dogs, or for us from the meat and bones I cook for the dogs. Here I was thinking I was the only one using that organic chicken fat for all kinds of things – seasoning cast iron, frying eggs, ‘buttering’ bread for grilled sandwiches.
I cook on propane, and start my stocks with roasting or browning, and then everything goes into a crockpot for a slow slow simmer of hours to days. If it’s for the dogs, I cook it until the bones and eggshells dissolve, then I give it a quick purée and throw it back in the crockpot with lentils. Stocks for us are used daily and also make much-coveted little gifts.