Don't waste that duck! How to render duck fat and clarify duck stock

If you've gone to the effort of roasting a beautiful duck, or making Peking Duck (read this fantastic post  here for a Peking Duck that is crispy skinned and delicious every time), it's a shame to waste any part of it. With a little extra effort that night and the following day, you can store the duck fat and make duck stock.

Both of these things are expensive to buy in stores and sometimes completely unavailable commercially. I haven't come across duck stock for sale anywhere, although chicken stock is ubiquitous. Duck stock tastes a little like chicken stock but it is richer and darker. It's wonderful to use for risottos, soups and sauces. Duck flavours go particularly well with mushrooms, potato, beetroot and any type of poultry where it can impart a complexity of flavour beyond that of the original bird. For this reason, it's great to have a carton of duck stock in your freezer - it keeps very well frozen and you'll always have it available.

Duck fat is even MORE useful. It has a high smoke point which means it doesn't burn like butter. You can use it for both shallow and deep frying. If you've used a large quantity you can strain it afterwards and re-use it. Roasting vegetables, particularly potatoes, in duck fat is well known to contribute both to their flavour and their crispiness. It can be used in salad dressings (you need to heat it slightly to make it liquid) and in making pastry, where it gives a fluffy light crispness. If you'd like some more detailed information on its uses, check here.

I hope I've convinced you of the usefulness of duck fat and stock - the best bit is that they take very little work to make if you have cooked a duck. (Obviously, they're a bit trickier if you haven't.) Basically you have to make both concurrently. Here's how.

How to clarify duck stock and render duck fat

After you have eaten your delicious duck and cleared the table, scrape all the bones, meat scraps, skin, etc into a saucepan. If you have cut off any parts of the duck prior to cooking (the neck or some of the fatty skin for example), reserve these at the time and add them in to the saucepan at this point. Add enough water to cover amply all of the bones, and put the saucepan on to simmer while you do the normal after dinner things (having dessert, washing the dishes, stacking the dishwasher, etc.)

At some point (I am assuming you have cooked and eaten your duck in the evening, for dinner) you will want to go to bed. Hopefully this will be at least an hour, possibly rather more, since you put the duck leftovers to simmer in the water. Before you go to bed, pass the duck mixture through a fine sieve into a ceramic or metal bowl. The sieve should catch all of the bones and solids while allowing the liquids to pass into the bowl. Discard all of the bones and solids. Cover the bowl with cling film and put it in the fridge overnight.

In the morning (or the following night, if you have to rush off to work first thing), you should find that your bowl of duck stock has magically separated, pushing the cream-coloured fat to the surface and creating a firm, clear jelly underneath.

If the fat is still liquid, put it back in the fridge for a while. You need it to be firm. It won't go hard exactly, but it will become pale and solid enough to scoop up in a spoon.

This shows the consistency the fat should be before you attempt to clarify the stock. It will be white and a bit grainy. It will be able to be manipulated in a soft but solid layer quite distinct from the stock beneath.

Using a spatula, roll the fat layer off the stock very carefully, trying not to bring any stock with you.

Scoop the fat into another bowl, separating it out from the stock.

Keep going until you have scooped out pretty much all of the fat from the stock. The bowl containing your fat will look a little like this (the dark patches are bits of stock that have unavoidably been transferred).

Your stock will look something like this. Most of the fat has been removed but a bit still remains around the edges and there are some patches in the middle that may have 'melted' a bit while you're working, making them difficult to scoop up.

Heat up both your bowls - the stock and the fat - to encourage the magical 'separation' process for both. This will help you get the last bits of fat out of the stock, and the last bits of stock out of the fat. Leave them both to cool - this may take a few more hours; if you do the first stage in the morning, leave the bowls in the fridge until the evening and then do the next stage.
When the remaining fat has again returned to the surface of the stock and has gone pale and somewhat solid, use a spatula or spoon to scrape it all away. You should end up with a clear jellied stock, with no fatty film on the surface.

Scoop this out into a container that you can microwave (or a saucepan). Be careful as you get down to the lower parts of the bowl - as you see here, there may be some grit and impurities at the bottom of the bowl. Discard these and only use the clear and pure jellied stock.

Heat until liquid, then transfer this to a bottle or lidded container and freeze it. You have made a beautiful, clarified duck stock!

Do the same thing with your duck fat - scrape any impurities off the top, then scoop the fat into another container. Be very careful as you get toward the bottom, as more impurities will collect there. It's important to get your duck fat as pure as possible so that it will keep well.

You should end up with a container full of very pure, creamy white duck fat. Seal the container and put it in the fridge. You now have wonderful, rendered duck fat!










That's all - I hope you enjoy this relatively simple process and get absolutely everything out of your duck!