DIY Cold Smoke Generator

A cold smoke generator is an affordable way to give your food that extra oomph, without a large outlay. You don’t need heat to smoke food. A cold smoke generator will allow you to make really scrummy food from the everyday.


To start cold smoking you will need:


One of these bad boys. it is a solid investment. Once bought you can cold smoke to your hearts content. So for an investment at the start you are free to carry on as you wish.

How the ProQ cold smoke generator works..

There is an entrance for a tealight at the bottom and separate to the dust holder. Ensure when you fill with the wood dust that you do not over fill, make sure to keep it even but that it does not exceed the metal route. The maze design is what means that the dust can smoke for so long without too much heat generated. What you do is light the tealight, pop it under the dust maze and wait for around 90 seconds or until the dust is both smoking and slightly glowing when you gently blow on to it. Remove the tealight. And then push the generator underneath your food inside of your cold smokehouse. It will not get hot and will be able to smoke for around ten hours without any worries.

It is very relaxing as a food lover! WE went for an entire range of wood dust and found the ProQ Smoking Wood Dust Variety Pack perfect. You can buy it combined with the maze for a saving, the ProQ Eco Smoker Setmakes a lovely fathers day gift for the foodie father!


How to Build a Cold Smoker

This is really not as hard as it sounds. There are options out there if you are not a DIY enthusiast.

You will need

  • 5 x pine 22mm x 47mm x 1.8m
  • 1 x pine 19mm x 19mm x 2.4m
  • angle edge plastic (you could use wood but it is much more expensive) 25mm x 25mm x 2.4m
  • 4 x thin ply wood 3.6mm thick 4 foot x 2 foot sheets
  • 1 handle of choice – could be a door knob you have spare
  • wood glue
  • 20 20mm screws
  • 20mm tacks
  • fine tooth saw
  • wood clamp
  • Bosch combi drill
  • posi screw driver
  • stanley knife – to tidy up the plastic

Lets get started!

We measured our existing racks and these fit to that. For your own version the height can stay the same but the width and the depth will need to be adjusted. Here is the one we used – Tala Cake Cooling Tray, 41 x 25cm x 3 if you want the exact same as ours.  

You will need to cut the pine into 2 x 1m lengths and 2 x 1.1m lengths. This is to give a slant forwards to allow for rainwater run off. It will also then become part of the roof ventilation system.

Measure your trays!

smoke generator

Dependent on the size of your trays you will need 6 x 24.5cm and 5 x 41cm of the pine.

By pairing a 1m with a 1.1m we are making the sides. The 24.5cm lengths are forming the horizontal supports, so equally space them with one for the bottom and move upwards. We attached with the glue and clamped them immediately. You can screw them but the pine wood is likely to split at this stage and cause movement.

A little patience required

cold smoke generator taking shape

Once they have dried, you will need to cut, the top edges so they are ready to take a sloping top. Take a ruler or piece of timber and draw a line across both of them, so that after cutting you can slide on a top without it getting stuck. With the 2 side frames ready you can now attach the 2 sides together. This can be a bit tricky, so you will need a flat surface and something like pots of paint or something weighty to hold the frames together for the glue to set. They don’t all have to be glued at the same time, so just do as many as you are comfortable with, whilst using the others as supports. This is not a quick process, I did it over a few days to make sure the glue had time to dry before gluing another piece. Keep the front edges flush, so it will be easier to slide the front on and off when finished. The neater you can make the frame, the easier it will be to cut and attach the ply wood.

Once you have finished your frames

cold smoke generator sides being added

Now that the frame is complete you can cut the ply wood. Measure the sides of the frame again (as even with the most careful of cuts, it may vary a little) You can cut the ply wood to be a couple of mm wider than the frame, this is not essential it just looks a bit tidier. Rest the frame on its side on top of the cut ply wood, mark the sloping edges at the top on the ply wood so you can cut this angle before attaching. Now with both sides cut and ready to attach, rest one of the sides onto the frame. Run some wood glue onto the frame of the front edge and place the plywood in place so it is flush with the frame all the way along the length.

When you are happy it is straight, put some weight, or some clamps, on to ensure the ply is flat to the frame all the way along. Once you are happy leave this to dry. Once dry turn the frame around and do the same for the rear edge. You can use tacks to attach the ply at the rear, or glue, or both. Again leave this to dry.

Measure twice!

With both side panels attached, you can now measure and cut the plywood for the rear panel. Once cut simply place on the frame and glue or tack in place. If you are tacking, be careful to support the frame when hammering the tacks in.

Now that three sides are complete you are ready to cut the front panel and attach the runners. Measure and cut the plywood for the front panel, so that it is no wider or taller than the box so far. The closer you can get it to the size of the box, the easier it will be to work with. When the panel is cut, lie the box on its back and rest the front panel in place. Take a strip of the angle plastic and cut 2 lengths for the full height of the box on the front edge. It is important when attaching these strips that there is enough of a gap for the front panel to slide in and out, but not so much of a gap that all of your smoke is going to escape. So, rest the front panel on the box and with the angle plastic over the edge of it, drill a pilot hole and then screw the plastic strip on to the side of the box. Repeat this process so you have 5 or 6 screws equally spaced along one side, and then do the same process for the other side. side panels added

I attached a handle onto the front panel, for ease of removal. You don’t have to do this but if you chose to remember to make sure the screws to hold the handle, don’t catch on the frame. Alternatively tack of glue the handle in place.

Your cold smoke generator should have 4 sides now…

handle attachedNow that you have a cabinet with 4 sides, you can make a top. I did this out of two pieces of left over ply. My thinking for this was that I’m not sure how much of a gap will be needed to keep the smoke in, whilst letting enough air to circulate to keep the sawdust smoldering. I measured the length between the edge of the plastic strip to the back of the cabinet and cut 2 more plastic angle strips. With these cut to length, trim the front edge so it can sit flush against the front runners. You can do this by simply marking the line you want to cut with a pen, and then using a Stanley knife to trim.

It is not important to have it looking nice, its just so you don’t catch it and break the runners. With the 2 pieces of plastic cut and trimmed, you will need to do the same process as you did for the front. Rest the pieces of ply that you have cut for the top, on top, and then rest the plastic angle strips on either side. Drill a pilot hole and screw the plastic strip to the frame on the front and back. You should now be able to move the 2 pieces of plywood back and forth to slide them in/out of the runners.

cold smoke ventilation is key to even smoking

End of the hard work, I promise

The hard work is now all done, all that is left is to cut some support strips to place inside of the box on either side to rest the racks on. Remember not to lace the bottom supports too close to the base, as you want a good gap between the smoking tray and the first rack. About 35 to 40 cm should be sufficient. The rest of the racks can go at any height, just leave enough of a gap to have room for whichever foods you are going to smoke. The rest is trial and error. You may have to put the cabinet on blocks to give a bit of an air gap at the bottom, and adjust the top to control the burn of the sawdust. Happy Smoking!

cold smoke generator

Cold smoking vs Hot smoking

Cold smoking lies at around 90 degrees and below. This means that bacteria is not killed by the smoking process, although the smoke is known to have antibacterial properties. It is therefore perfect for foods designed to be eaten ‘raw’ like dairy, vegetables etc or foods designed to be cooked thoroughly later on. You can also use ready cured meats or fish as well.

Hot smoke is above 135 degrees Fahrenheit and is suitable to kill germs as well. GrillBeast have some great tips for hot smoking. We are mainly going to start with the cold smoke process though.

How to Cold Smoke

We are experimenting with cheese and rock salt to begin with. We have let it smoke for ten – twelve hours and then we leave the cheese for a further week in the fridge. The reason for this is that the outside will be lovely and smokey but inside will need a bit more time to infuse. We will also be cold smoking nuts when they are in season!

veggies for the cold smoke generator
Tell me these veggies aren’t all going to taste better once cold smoked!

We love our cheeses. I am looking forward to trying applewood cold smoked Feta and Avocado Guacamole as i think it will really lift it even higher! Or our Slow Roasted Cherry Tomatoes with some hickory smoked mozzarella balls!


How long to cold smoke cheese

10-12 hours works well for harder cheeses and soft cheeses alike. There is no hard and fast rule with this, but we like quite a robust flavour, so the ‘resting’ time is key! Leave for at least a week in the fridge, wrapped up and looked after! That is almost as important as the time in the cold smoke generator. We plan on smoking some garlic bulbs in July as well to see how that turns out.


cold smoke salmon!
Try telling yourself you don’t fancy trying to cold smoke some fresh salmon for yourself!

I really think that these make the best gifts for gardeners, so I have included them in my latest article –Great Birthday Gifts for Gardeners so if you would like more inspiration check it out.