Chisel me of a chunk of dessert, will ya?

August 20, 2012 11:47 AM

Food chemists! Help me make a sorbet! Challenge level: Spoonable AND sugar free.

So the idea is I want to make a sweet creamy fruit sorbet. Traditionally, in addition to fruit purees and juices (ingredients I intend to use) there is a lot of sugar or corn syrup (ingredients I don't intend to use). ARTIFICIAL SWEETENER IS A-OK WITH ME. So if I want to punch up the sweet factor with Splenda, Stevia, etc that's cool.

The problem: I can make a juice/puree/sweetener mix and churn it in my ice cream maker and it's good to go right then. But when I pack it into the freezer for eating later it brickifies due to all the water. The traditional solution (Solution? Ha! Get it?) is to use sugar--lots of it. Or sometimes people will use vodka as an "anti-freeze". The problem with sugar is I don't want to use it and my concern with vodka is that in the absence of sugar I would have to use so much of it I have crossed into something other than dessert territory.

So are there any additives: anti-freezes, emulsifiers, anything to break up those ice crystals and keep it spoonable during storage? I'm not afraid of things not found at the supermarket, so if I have to order something normally used for more commercial use I'm OK with that. Thanks!

posted by sourwookie to Food & Drink (8 answers total)

Hm, I wonder if xanthan gum would do something useful here.
posted by elizardbits at 11:55 AM on August 20, 2012

Are you open to mechanical solutions? Maybe you could buy a shaved ice machine with a few spare molds and pack your fresh sorbet into those, then run them through the machine just prior to serving.
posted by contraption at 11:57 AM on August 20, 2012

What about Lambic beer? I have a copy of Jeni's Splendid Ice Creams, and she suggests a fruit and lambic sorbet (she does add sugar, btw). She also makes a citrus sorbet using pectin, perhaps you might consider that as a possible solution as well?
posted by LN at 11:59 AM on August 20, 2012

Citrus liqueurs also add a nice dimension to sorbet while contributing an antifreeze effect. Have you experimented with alcohol at all to see if you can get close to the desired consistency without making it overpoweringly boozy? If you're using a lot of sweet fruit juice it might just work.

Also, this Chowhound thread looks like a good starting point for freezer-stable thickening agents.
posted by contraption at 12:07 PM on August 20, 2012

The word you're looking for here is POLYDEXTROSE. It is a fiber that provides the bulking characteristics of sugar. Maltitol will also work, but it will absolutely murder you gastrointestinally.

You need to use a second sweetener with PolyD since it has only around ten percent the sweetness of sugar; I use sucralose. I also use erythritol, since there is a synergy that happens when you use sweeteners from different families where they sort of multiply each other so you end up using less of each of them. This means less of any individual aftertaste, a rounder overall sweetness, and you spread out the risk of using too much of whichever one it is that they're going to find out will kill you.

This is the blend I use. I'm not even sure all these things are necessary, but it works and I don't want to risk a batch of ice cream to test changes.

For a standard batch of ice cream that calls for a cup of sugar, I use:
1 cup polydextrose
1/4 cup erythritol (you could also use xylitol)
1/4 cup sucralose (I use six drops of Sweetzfree sucralose concentrate)
1 teaspoon maltitol (honestly, just because it's there and I never use it for anything else. Used more for synergy than for bulking)
1 teaspoon lecithin
1 teaspoon glycerin

You can get polydextrose and erythritol at Honeyville Grain. If you do a lot of sugar-free baking, they are invaluable. PolyD is the secret to gooeyness. It basically has all the properties of sugar that Splenda lacks. (warning: it is fiber, and lots of it. You might have a little gassiness if you're not used to eating a lot of fiber.) Erythritol or xylitol are good for adding synergy and a sugary crunch (mostly evident in cookie dough). Be aware that you need to warm the liquid you add them to, and make sure they are dissolved, or they will make horrid hard clumps in your final product.
posted by bink at 12:21 PM on August 20, 2012

Dammit, I was going to link to the chow hound thread.

But I will add --- for myself, I think a couple tablespoons of corn syrup would work wonders. Pastry Chef and blogger Dave Leibowitz discuses the pros and cons of it here -- but basically, due to its chemical structure it inhibits crystal formation, and in my experience you really don't need a lot to notice the effect. Especially if you're doing a watery fruit like citrus or melon.
posted by Diablevert at 12:22 PM on August 20, 2012

It looks like guar gum or xanthan gum are what you want. Here's a rundown of various common "gums", emulsifiers to break-up crystal formation. Here's an NPR interview that recommends guar gum. More comments from a Stackexchange thread.
posted by bonehead at 12:25 PM on August 20, 2012

This recipe over at the Kitchn has been super popular the last couple years. You can have whatever flavor you like, as long as it's banana. :)
posted by mon-ma-tron at 1:17 PM on August 20, 2012