In candy making, there are several stages through which candy goes as it is being heated. These include the thread, soft ball, hard ball and soft and hard crack stages. Hard ball stage is used to make certain types of candy like nougats, marshmallows, and divinity.
Specifically, hard ball stage refers to cooking candy to a certain temperature, usually between 250-265 degrees F (121.11-129.44 degrees C). If you are not an expert candy maker, it’s a very good idea to use a candy thermometer to determine when you’ve hit this stage. There are other tests which can help you decide if the candy is at the appropriate temperature, but these need to be done swiftly, and with great care, so you don’t burn yourself, or the candy.
As sugar and other candy ingredients cook, the water begins to evaporate. When sugar reaches the hard ball stage it only has about 8% of its original moisture content. If you dip a spoon into candy at this temperature, and remove it, you’ll note that the sugar drips off the spoon in thick ropes. You can also drop a bit of the syrup into cold water, and it will form a ball. When you remove it, the ball will remain formed, although it won’t be completely hard.
This is distinctly different from soft ball stage, which occurs at a lower temperature. Soft ball will not hold its shape when removed from water. There’s also a stage in between hard ball and soft ball called firm ball, which occurs at 245-250 degrees F (118.33- 121.11 degrees C). The main difference between hard ball and firm ball is that you can flatten firm ball candy. You can bend hard ball stage candy and it will give to pressure, but you cannot completely flatten it.
When you’re performing these tests, you must keep an eye on your candy, since it can quickly progress from hard ball to soft crack. If you’re making certain forms of nougat, waiting around to test can mean you’ve ruined your candy. You should go quickly, keep a glass of water by the pot you’re cooking candy in, and be sure to use oven mitts when removing candy so you don’t get burned, which can likewise ruin your day.
Quickly test the candy, but also rely on the candy thermometer to tell you when you’ve reached hard ball stage. A good indication, even before you’ve dropped a sample of the candy in water, is to watch the way the heated sugar falls off the spoon. If it’s coming off in thick ropes, and your thermometer is at the right temperature, chances are you may not even need to perform the squish test to make sure you’ve reached hard ball stage.