Episode 54 – Grapefruit Sorbet

Episode 54
June 12, 2011
Grapefruit Sorbet

Now that summer is in full swing I’d say this is a good time for another kind of frozen dessert.  Unlike ice cream, sorbet doesn’t contain any eggs or milk.  Sorbet that contains dairy products like milk or cream is called sherbet.  Looking at the most basic recipe, sorbet is simply simple syrup and fruit juice.  While making sorbets seems simple there are a few things you need to know in order to be successful.

The number one reason why people fail at making sorbet is too much sugar.  Sugar is introduced into a sorbet by using a simple syrup.  Simple syrups are usually made using a 1:1 ratio of sugar and water (with just a pinch of cream of tartar) and then brought to a boil on the stove.  In this recipe we actually use 13 ounces of granulated sugar and 7 ounces of water, to help speed things up on the stove.  For this sorbet recipe, once the simple syrup is brought to a boil continue to let it boil until it reaches about 225 degrees F.  This is a good starting point for sorbets.

The next step is to alter the baume.  Baume is the measurement of a liquid’s density and in

A baume scale in the sorbet base. In the video I say that the baume is 16 degrees but in this picture it's clearly at 17 degrees. To read the baume just look at where the line matches up with the surface of the liquid.

pastry we use it to measure how much sugar is in a sugar-liquid mixture.  Baume is measured with a baume scale which is carefully dropped into the liquid – where the surface of the liquid meets the measurements on the side of the baume scale is the degrees baume of the liquid.  Generally speaking, a simple syrup heated to 225 degrees F on the stove should land somewhere between 37 and 41 degrees baume.  For a sorbet to freeze your baume must be between 14 and 18 degrees baume.

If your sorbet base is higher than 18 degrees baume, then it will simply not freeze.  This is essential to making a successful sorbet.  If your sorbet base is below 14 degrees baume, then your sorbet will resemble granita (shaved ice, chipped ice, sno-cone) in texture.  Sorbet bases that are between 17-18 degrees baume will be softer and creamier in texture, sweeter in flavor, and will melt quickly.  Sorbet bases that are between 14-15 degrees baume will be a little harder and icy in texture, milder in flavor, and will stay frozen longer when served.

I wish I had a white egg when I did this but as you can see the egg floats in the sorbet base. The protuding part is a little bigger than a quarter in size.

With all this in mind, most home bakers will not already own a baume scale (baume scales are pretty easy to find for sale online).  Another trick to checking the amount of sugar in your sorbet base is to use an egg.  Carefully drop an egg in the base and wait for it to float to the surface.  The exposed surface should be about the size of a quarter.  If it is larger than a quarter than your sorbet’s baume is high (18+ degrees baume) and it is smaller than a quarter or not visible at all then your sorbet’s baume is low (14- degrees baume).

While the egg trick is a little inaccurate and hard to measure it is easier to use than a baume scale.  A baume scale is tall so your base and container needs to be pretty deep in order for you to take an accurate reading – especially at lower degrees baume.  An egg is a little shorter than a baume scale so you might be able to leave the egg in the sorbet base while you are adding sugar or fruit juice – giving you a real time measurement.

That’s one way of  making a sorbet base.  Start with either the fruit juice or the simple syrup (it’s usually easier to start with the fruit juice) and continue adding the opposite ingredient until the egg or baume scale measure the desired baume.  The other method, the method I use in the video, is a little messier but if you aren’t making a lot of base it’s a little easier to use.  Combine the fruit juice and simple syrup, pour it into a smaller container for measuring purposes, then combine them back together again after taking the measurement and adjust accordingly.  Whichever method you choose you’ll probably need a little bit of both ingredients (simple syrup and fruit juice) so you can go back and forth getting to the desired degrees baume.

Another thing to remember when taking a baume reading is the liquid needs to be around room temperature (70 – 75 degrees F).  If the liquid is too hot the reading might be lower than it really is and if it is too cold the reading might be higher than what it really is.  Granted if your sorbet base is between 65 – 85 degrees F I doubt it would have enough of an impact to throw your baume reading off by that much.  However, it’s important to make note of it.  Just remember that a baume reading could be off if the base is not at room temperature.

As for the kind of juice you want to use, feel free to use whatever juice or liquid seems

I attempted to measure the egg but without being able to put the ruler right up against the egg it was difficult. It 1" is what we're aiming for +/- 1/4 inch. It's probably safer to be under an inch.

interesting to you.  Sorbet lends itself well to almost any fruit flavor and this recipe is easy to customize.  The only rule with sorbet is that it needs to land between 14 and 18 degrees baume  – after that there is a world of possibilities.  Try infusing spice, herbal, and tea flavors while boiling your simple syrup on the stove.  Try using fresh fruit to add extra texture to your finished product.  Try using zest for a burst of flavor or boiling the juice for a different kind of flavor.  Many fruit juices change their flavor slightly after being boiled on the stove.  Sugars caramelize and flavors concentrate giving you a sweeter or candy-like flavor.

Keep in mind that if you use champagne or wine as a flavoring agent your sorbet will not freeze as well.  That’s because alcohol inhibits freezing.  If you are using an alcohol in your sorbet base be sure to land on the lower end of the baume – perhaps even lower.  Just for the sake of an example think of alcohol as +2 baume.  So let’s say you have a raspberry and port wine sorbet base at 18 degrees baume.  Since port wine has alcohol in it, your sorbet will be inhibited from freezing and will freeze like a sorbet base at 20 degrees baume.  Now I’m not exactly sure what the measurements are and how it affects the freezing process precisely but use the above example to illustrate in your mind how you want your base to read.  In the end, if you mess up and it doesn’t freeze just add more liquid (water or juice) and try again.

You can use sorbet for a variety of purposes – purposes beyond enjoying it as a solo dessert.  For one, you can use it to provide color, shape, and flavor contrast to your plated dessert presentation.  Another popular use of sorbet is as an intermezzo, or palate cleanser, in between meals in a multiple course meal.  Because sorbets have very few ingredients it works perfectly for refreshing your mouth for the next course.  Popular intermezzo sorbet flavors are usually citrus but there isn’t any reason why it couldn’t be any kind of fruit flavor.

After playing around and making a couple of sorbets try experimenting with different ingredients and making your sorbet into a different kind of frozen dessert.  As I mentioned earlier, adding milk or cream will turn your sorbet into sherbet.  Sherbet has a creamy-like texture that is reminiscent of ice cream and sorbet at the same time.  The most popular sherbet flavors are orange (like a creamsicle) or rainbow.  Folding in an Italian meringue (a French meringue with a simple syrup heated to 250 degrees F) to a sorbet base during the freezing process creates a spoom.  While I have never had a spoom it sounds like a delicious experiment and to be honest I bet a Swiss meringue would work well too.  Spooms are traditionally made with a wine or champagne flavor but I bet any fruit flavor would taste great.

In the video you may notice that my simple syrup is pretty cloudy and that’s because my simple syrup had crystallized while it was cooling off.  It was crystallizing pretty slowly so much of it was still fluid and I decided to risk it and strain out the hard chunks and use what was left – in an effort to save time and not waste my ingredients.  It seemed to work fine but keep in mind once the crystallization process has began it’s not going to stop.  It could very well be crystallizing while the sorbet sits in my freezer changing the texture of my sorbet.  If your simple syrup crystallizes but you think it may still be usable that’s going to be a judgement call.  I’d say if you were serving the sorbet today it might be okay to use but other than that you might want to start over.  In my experience, simple syrup seems to be more susceptible to crystallization when it’s cooked to high temperature (like 225 degrees F) so if you’re having trouble try aiming at a lower temperature.  You can still achieve the correct level of baume with a thinner simple syrup – you just need less grapefruit juice.

That’s pretty much everything I know about sorbets!  This is probably one of the few videos you probably don’t have to watch if you’ve read the blog post since there are no complicated or tricky steps.  In the video I reiterate what’s written here, I show you how a baume scale works, how the egg trick works, and what the finished product looks like so it still might be worth watching!  Here’s the recipe for grapefruit sorbet, which works under the assumption you won’t be taking the baume measures at all (neither scale nor egg) but keep in mind that unless you take a measurement your finished sorbet may be a little off in texture.  Enjoy the video below!