As an espresso lover, I was so incredibly amped to finally get an espresso machine (the Breville Barista Pro, for those wondering). I had the best coffee beans, I perfected my ratios and I nailed the preparation. What I didn't have was a knock box.
The first time I pulled a shot, I was ecstatic. And then I went to throw away the puck — the spent espresso grounds left in the portafilter — in my trash can. If you wanted to find your way to my trash can from my espresso machine, all you had to do was follow the drip, drip, drip on the floor. It didn't take me long to realize I needed a knock box. Ever since I got one, I haven't had to scurry to the trash can after every shot I pulled, and now it's time that you, an espresso machine owner, get one too.
What Is a Knock Box?
A knock box is a little box you set next to your espresso machine so that you can easily (and cleanly) throw away your pucks after every time you pull a shot. What makes a knock box a knock box is a bar that runs horizontally across the box for you to bang your portafilter to expel the puck.
After you pull a shot, the puck is wet and hot. The moisture of the puck makes it get stuck inside the filter, and the puck is way too hot to go jamming your finger in there. Knocking the portafilter against the bar helps to get you a clean filter in almost no time at all.
Do I Need a Knock Box?
You don't really need a knock box, but there are more reasons to buy one than there are reasons not to buy one.
Instead of running back and forth between your espresso machine and your trash can, the knock box becomes a trash can. (Just don't throw anything that's not a coffee puck in there.) Also, if you're pulling a lot of shots, cleaning out your portafilter over and over becomes as easy as knocking on a door, er, knock box.
They keep things clean
You already heard me whine about dripping coffee on the floor, but since I got a knock box, you won't find any coffee drips on my floor. And because your knock box is probably just a couple inches from your espresso machine, there won't be any coffee drips on your countertop either. Just remember to empty the knock box regularly. Because the pucks are so wet and densely packed, they're prone to developing mold. It happened to me. Don't be like me.
What Should I Look for in a Knock Box?
Not all knock boxes are the same, and that helps with finding one that's right for you. Here's what to consider when shopping for a knock box.
You're probably not pulling shots at the same capacity as a cafe, so find a knock box that has enough space to hold a few pucks so you don't have to constantly empty it. Also, your espresso machine probably takes up a lot of prime countertop real estate so you might not be able to make space for an extra-large knock box.
Since you're going to be beating the crap out of your knock box, you'll want to find one that'll hold up against constant poundings. Metal and rubber are both good materials. Metal, on one hand, will be strong and hold up for a long time, but they will be a little pricier. Rubber knock boxes are affordable but that rubber won't last very long.
Five to Buy
Choice 6" Deep Espresso Knock Box
No bells, no whistles — just a damn good knock box for cheap.
Breville Knock Box Mini
It's cheap and easy to clean, and best of all, it perfectly complements all of Breville's similarly designed espresso machines.
Dreamfarm Espresso Knock Box
Made of solid steel, this compact knock box can take a decent beating. Plus, it's safe to throw in the dishwasher.
Crema Coffee The Arc Knock Box
Designed to hold up to 16 pucks, the Arc Knock Box is one of the nicest ones on the market, and its lid helps you keep your spent pucks from stinking up your kitchen.
Rattleware Maple Knock Box
Rattleware's knock box has a stainless steel insert housed inside an attractive maple wood box. Its rubberized feet prevent slippage, and there's a replaceable cover.