But how hot should the coffee be?
There are few things more appreciated after a stroll through temperatures hovering around zero than a steaming hot cup to wrap your hands around. But are you compromising the taste of your coffee when you try to please those customers demanding their coffee ‘extra hot’?
The short answer is yes. Both the temperature at which you brew the espresso at, and the temperature at which you steam the milk for lattes and so on, make a difference to taste and texture.
Let’s look at espresso brew temperature first
Anecdotally, it even starts with the grind – the theory being that the hotter your grinder becomes, the more soluble the ground coffee becomes, and the greater the extraction. This won’t have a direct effect on coffee serving temperature, of course, but it might have a bearing on how hot you need to brew your espresso for the right yield and the right flavour.
A lower brew temperature tends to bring out the acidity of the coffee, while pushing that temperature up can bring the acidity down. With the higher temperature comes more sweetness and body, the lower temperatures the opposite. Most baristas will brew coffee at 195°F-205°F/ 90.5°C-96°C. We find that when the temperature creeps up past 96°C, the texture can become a little powdery, and when it’s at the lower range it’s not quite sweet enough. Which means the sweet spot – for our palettes, at least – is at around or just over 94°C/201°F. Of course, to gain this level of control, you need a decent commercial espresso machine.
So, at the ideal temperature for taste, you’d be serving a pretty piping hot espresso. But as soon as you add milk – even steamed at the highest temperature advisable for taste and texture – you’re bringing the overall coffee temperature down.
Milk temperatures for lattes and cappuccinos
Head to Italy and, if your barista has followed guidelines from the Istituto Italiano Espresso Nazionale, you may find your cappuccino has been made with the milk steamed to 55°C. An absolutely drinkable temperature, but with a wintry wind, cold in no time. You can, of course, steam milk hotter. Go much past 70°C and you’re going to get a burnt flavour and the milk sours. The sweet spot here – and again, sweet spot is literal because the lactose dissolves in the milk and gives a sweeter taste – is in the 60°C-68°C range. We think 63°C is about right.
But if your customers are asking for extra hot – and especially if they’re taking it in a takeaway cup – then you might want to push the mercury up the thermometer a few more degrees.
Pleasing those customers nursing your best china, rather than a (hopefully recyclable) takeaway cup, you can brew and steam at the right temperature for taste, and still heat those cold fingers nicely. It’s just a question of preheating your cups.
Choose a coffee machine with top storage and you’ll get a certain amount of pre-warming, but for a properly hot cup in which the coffee you serve will hold its temperature even as the customer perches outside, just use your steam boiler water. Even half-filling the cup or mug should bring the temperature up nicely. Couldn’t be easier, and your customers couldn’t be happier. Just make sure you warn them before they take their first slug!