Now, sorbets like all the desserts we call Water Ices, are born from simple syrup. But, as this sucrose model clearly shows there's more to simple syrup than just sugar water. See, it all has to do with the way these hydroxyl groups stick out from the rings of the sucrose molecule. They promote hydrogen bonding and since water is basically a hydrogen based atom, it ... yeah, whatever.
[SUCROSE DIAGRAM HERE]
Sucrose + H20 + Heat = Syrup
Look, the sugar in frozen desserts is more than just a sweetener. See, once dissolved in the liquid, the sugar molecules actually get in the way of ice crystals forming. Now as more water does freeze, the remaining liquid becomes more and more concentrated with sugar which continually lowers the freezing point. That means that an ice or sorbet is little more than tiny ice crystals suspended in a supersaturated sugar solution that's basically never really going to freeze, not all the way.
Now, too little sugar and you'll need an ice pick to serve your dessert. Too much, and you'll have a syrupy mess.
Low Sugar = Rock Hard
High Sugar = Syrupy Mess
So, the trick, if you can all it a trick, is in nailing the right amount of sugar. And for that, well, all you need is your trusty sucrometer. Lent yours to the neighbor? Never got it back? No problem. A few simple rules will do.
Now, when I want a scoopable ice I go with 7 ounces of sugar, roughly a cup, to every 16 ounces of liquid by weight. Now that's roughly, uh, 30 percent sugar.
7 oz Sugar (by weight)
Now, the liquid could be water or a mixture of water and unsweetened fruit juice but since they don't contain any sugar, which would throw off the equation, flavored sparkling waters work well. I usually keep a few bottles of this on hand anyway.
And, I'm going to substitute one of the two cups of sugar that our recipe calls for with one cup key lime preserves. Adding preserves to frozen desserts is good science for three reasons. One, you can count it as you would an equal amount of sugar in the recipe. Tablespoon for tablespoon, cup for cup. Two, it's a great way to introduce flavor. And three, pectin, the substance that thickens preserves make ices smoother. Not only do the large pectin molecules prevent crystals from getting big, just by getting in the way, but when smaller crystals melt on the plate, the pectin holds them in a gel state, which means a slower melting dessert. Ain't science cool?
Count preserves as sugar in recipe
Pectin adds stability
|We're going to start by dissolving about a cup of our lime preserves along with a cup of sugar and about a cup of the lime seltzer over medium low heat. We don't want to let this boil because the pectins and the preserves will be damaged and we need those little molecules. So just stir that to dissolve.||
1 cup preserves
|We're also going to add the zest of one lemon and one lime—the zest only, none of the nasty white stuff—and the juice from said citrus. But, hold back about a tablespoon for fine adjustment later.||
Zest & juice of
|Then the final ingredient not be missed, salt. Just a pinch. Now, I know. You're saying, this is dessert what's salt got to do with it? Well, salt enhances flavors, especially the kinds of flavors that could get lost in all this sweetness. Believe me, you will never notice it's there until it's not, if that makes sense. Yeah. Stir, until dissolved.||
Pinch of Kosher Salt
| Once everything
is dissolved, go ahead and add the rest of the lime seltzer. Slowly. There we
go. And then give it a taste.
3 more cups of seltzer
Now remember, when we eat this it's going to be cold and
cold numbs the tongue so it needs to be very strongly flavored at this point,
very sweet and very tart. I think it could use a little more acid so I'm
going to add the rest of that citrus juice. Give it a final stir
pour it into a wide, clean, lidded container.
Now here is one of the crucial points of making frozen desserts. The mixture has got to be cold before you freeze it. See, cold liquids support seed or baby ice crystals better than warm liquids do and that ensures a fine grain, which is what it's all about. So take the extra time and 'chill.'
GUESTS: Ice Cream Churn Kid #1, #2, #3
To achieve the smoothness and creamy texture that is the
hallmark of sorbet and ice cream, you need small, little ice crystals in air frozen
right into the mix. And that, my friend, takes technology. Now, the modern ice
age began in the 17th century when science types figured out endothermic effect.
That's the ability of
salt and ice to combine and form a liquid
that's actually colder than ice itself. Anybody who's churned ice cream or
driven a Detroit street in winter has experienced endothermic effect firsthand.
Now, the next big breakthrough in ice cream technology came with that little contraption dreamed up by one Nancy Johnson in 1843. Had the New Jersey housewife known she was handing America a century of dessert superiority she probably wouldn't have sold her patent rights for $200. I bet her great, great, great, grandchildren are still steamed about that one.
KID #1: Uncle AB, this isn't as fun as you said it was.
Everything about the Johnson machine was wonderful. It was revolutionary. A sealed drum submerged in an ice brine ...
K #1: Uncle AB.
... turned by a gear around an internal dasher, a churn, that ...
K #1: Uncle AB.
... scraped the baby ice crystals from the walls of the can while whipping air into the mixture. It was perfect.
K #1: This is getting harder. I want my money back.
AB: That's when you crank even harder.
This is why manual machines are still the best. See, when you feel resistance you know the mix is ready to take on air so you ...
AB: [overly loud to his nephew behind him] ... crank even harder.
See, electric versions they can't do that. Air is what gives American style ice cream its light body and not too chilly mouth feel. Now, Italian gelato doesn't have nearly as much air in it which is why it has a denser, colder mouth feel.
AB: Keep cranking.
Welcome to ice cream, Italian
style. Now, long
before Mrs. Johnson got her crank out, the Italians were crazy about frozen
desserts. The emperor Nero, in fact, well besides being just plain crazy,
was so crazy about ices that he actually had slaves go up in the mountains and
harvest snow which he then hid in caves so that he could enjoy it year around.
Now, unlike the American tradition of ice cream which depends on cream or the French tradition that revolves around egg custard, Italian gelato is usually milk based so it's a slightly lighter product.
Now, when it comes to technology, well, while we were busy developing space shuttles, the Italians were busy perfecting Mrs. Johnson dream. This high tech wonder here is state-of-the-art and represents about a century of dogged innovation.
Fancy Italian Gelato Machine
66% of the ice cream bought in the USA is eaten by adults.
GUEST: "W", Equipment Specialist
Luckily there's some middle ground between Mrs. Johnson's, well, less than convenient contraption, and that dairy Ferrari that we saw a few minutes ago. See, in the last few years there's been a veritable spawning of counter top ice cream freezers and some of them are perfect for the modern kitchen landscape.
W: Come on. We don't have much time.
AB: Hello, W.
W: Hurry up, AB. Unless you've got a $1,000 in your pocket you want to stick with a counter top model, one that utilizes a sealed canister containing a solution capable of delivering subfreezing temperatures.
AB: Subfreezing temperatures, of course.
W: This little electric version is simple, reliable, easy to clean ... put that back ... and includes an automatically reversing motor that cranks out a quart in about a half an hour.
AB: Quart in half.
W: There are several makes of this kind of design but this one has a chute for adding ingredients during operation.
W: Now go freeze, AB.
AB: Time to turn.
Our ice cream machine is
turning. The lime
ice mix is cold and ready to turn. And this is all there is to it. There's only about a quart of liquid here, so it's not going
to take more than, I'd say, half an hour to soft set which is what we
want. So, why do we really need one of these? Can't we just
chunk it into the freezer? Well, without agitation to promote lots
of little baby crystals, a 30% solution, like the one we have here,
would freeze into a big ice cube floating in a syrupy mess which isn't
too appealing. But, if we were to cut back on the sugar, well that
would be another story, one we think is worth telling.
The Italians are masters at ready-made desserts and their icy granita is the perfect example. As a matter of fact the most famous form of granita is based on something us Americans throw down the drain everyday, coffee. Now, espresso would be preferable but strong coffee will do the job.
|We're going to start with about 2 cups of hot Joe and into that we'll dissolve 1/3 of a cup of sugar. Now, some simple math will tell us that that's only about a 15% sugar solution. Now, we would need 30% for this to be a scoopable frozen dessert so we know that it's going to be hard and icy. But that's okay because we've got a whole different ball game going here.||
2 cups hot coffee
|Now, if you were in Venice, which is where the dish originated, you might add about, oh, a tablespoon of coffee liqueur and a pinch of citrus zest. I like to use a combination of orange and lemon.||
1 Tbsp coffee liqueur
Make sure that everything is mixed
together and dissolved and we're going to pour it into a wide pan so that the
liquid only comes up about, oh, a 1/4 of an inch up the side of the pan. That
looks about right. Now, straight into the freezer for about half an hour to 45 minutes. Then the action starts.
In half an hour, pay your mixture a visit and bring a fork. Scrape and break up any ice that's formed around the sides. Come back every 15 to 20 minutes and scrape new crystals as they form. This repeated tearing down of the ice produces a light but flaky texture. Now, when the mixture is completely frozen fluff it with a fork and leave it to dry for about an hour before serving.
Just fill a goblet with your newly formed crystals, top that with some barely sweetened whip cream, maybe a little bit of lemon zest just to top things off and there you've got it. The perfect hot-summer, afternoon date.
Half and hour of TV time has slipped by and the Key Lime Sorbet has taken it's last turn. Take a look. Just a bunch of big blobs of fine little crystals. Now, we could serve this now but it would melt really quick. So harden it in the freezer for a couple of hours before serving.
Now one more thing about ices, if you think the flavor needs more of this little more of that, just let it melt, make your changes, and turn it again. If you accidentally leave it out on the counter for an hour, you're actually better off letting it melt the rest of the way and returning it than you are putting it back in the freezer.
|They are two schools of thought regarding ice cream. One proclaims that cream or milk, eggs or egg yolks, sugar, and various flavorings should be cooked together over low heat, cooled, and then frozen. Now older cookbooks refer to this as New York ice cream and at least 90% of the ice cream recipes written today toe this line. To me, this is not ice cream. This is frozen custard.||
|Yet we in the ice cream underground believe that ice cream should be just that, milk or cream, frozen with sugar and flavorings. That's it. No double boilers, no separating eggs, no tempering yolks, no stirring for half an hour. Now this kind of ice cream is referred to as Philadelphia style ice cream and it all starts right here. [indicates milk]||
|Now, it's tough to mess up ice cream as long as you follow some simple rules. Now, you can use almost anything from whole milk to whipping cream, alone or in combination just as long as you avoid heavy whipping cream or what the English call, double cream. It's got too much fat in it. You'll make butter before you make ice cream.||
Heavy Whipping Cream
| Now, light
cream used to be my favorite but you almost never see it anymore so I go
with 2 parts Half & Half and one part whipping cream
Light Whipping Cream
2 Parts Half & Half
|Remember the steps to our sorbet? Mix, chill, turn and harden? Well, ice cream has a few more steps, but they're easy.||
|For starters, I'm going to bring 2 cups of Half & Half and 1 cup of whipping cream to 175 degrees over medium heat. Now, if you don't have a thermometer bring it to a bare simmer, but don't skip this step. It's going to make a huge difference to the end result.||
2 Cups Half & Half
Now is also the time to add some mysterious and exotic flavor.
Imagine a flower, a climbing orchid to be exact. The one of some 20,000 varieties that produces something edible. Now, imagine that its blooms must be pollinated either by hand or a small variety of Mexican bee and that each bloom only opens for 1 day a year. Now, imagine the fruit of this orchid, a pod, being picked and cured, sitting in the sun all day, sweating under blankets all night for months until shrunken and shriveled it develops a heady, exotic perfume and flavor. Now, imagine that this fruit's name is synonymous with dull, boring and ordinary. How vanilla got this bad rap, I for one will never know. What I do know is that vanilla and ice cream were meant for one another. And to get the true essence of the bean, you got to use the bean.
Although vanilla from Madagascar is
the most popular,
beans from Mexico are the most flavorful.
Regardless of the variety, the best
pods have a kind of white, crystalline powder on them. That's the
actual vanillin, the chemical compound that provides the flavor. So, the more white, the better.
Now wrapped in plastic or sealed in a glass jar and refrigerated, whole beans will keep their flavor for about 6 months. After that they start to lose a little of their magic. For our batch of vanilla ice cream one bean will be enough but we want to get all the little black specks and pulp that comes from the inside of the bean. So just split it down the middle with a paring knife, scrape the seeds out ...
...and put the whole thing in the pot.
|As soon as your mixture comes to 175 degrees kill the heat and add your other ingredients.||
|Now, sugar is the next big player and for three cups dairy I usually go with 1 cup. But, since I'd like some extra smoothness in my ice cream and a little accent flavor and since I can interchange sugar directly for preserves I'm going to remove 3 tablespoons of this sugar and replace it with 3 tablespoons of the preserves, peach preserves I might add. Just add that right to the mix and stir until the preserves have completely dissolved. Oh, and don't forget pinch of salt.||
- 3 Tbsp Sugar
+ 3 Tbsp Preserves
Okay, our vanilla ice cream mixture has come down to room temperature and we've reached a kind of secret milestone in ice cream making. It's the kind of secret that ice cream manufacturers don't let leak out of their vaults. And it's this: age the mixture in the refrigerator for at least 6 hours or better yet overnight. Why? Well, with all that heat we've put a lot of changes into motion inside the dairy and they need time to finish doing their thing. A rested mix will create a texture that any other ice cream, even a custard based ice cream, can not match. And, like ices, the colder the mix is before you start turning, the finer the texture will be.
The ice cream cone was invented at the 1904 World's Fair in St. Louis
Our ice cream machine is turning and our vanilla mix is not only cold but mellowed for 12 hours ... haven't we
done this before ... anyway, time to turn.
Now, freezing ice cream
is a lot like freezing sorbet.
By the time it reaches soft serve consistency, all of the ice crystals that are going to be formed in the ice cream have been and all the air that can worked in has been. In this case I'd say that it's about 100% air since it's doubled in volume. Now, just like sorbet, ice cream should be hardened in the freezer for at least a couple of hours before serving.
During prohibition may bars
converted to ice cream parlors.
Most were so profitable they never changed back.
go. I'll be back for you in a
couple of hours. By the way, every time you take a sorbet or ice
cream out of here [the freezer] some of the smaller ice crystals are going to melt. Now when that water refreezes, it's going to join up with
larger crystals that survived the thaw. That means every
trip a sorbet or ice cream makes out into the world the grainier it's
going to be the next time around.
Now, to minimize this vicious cycle split up large homemade batches into several small containers. Then just break them out as you need them. If nasty, big grains aren't enough to convince you, ponder this. When exposed to air for long periods of time ice cream gets leathery from surface evaporation and it can pick up some pretty funky flavors that float around inside a freezer. So, take a cue from premium ice cream makers and push a heavy layer of plastic wrap or even wax paper right down on the surface of the ice cream before you put the lid on. No exposure to air, no leathery surface. Your ice cream will thank you.
Oh, and remember ice cream and sorbet hate living in the door.
GUEST: Man Buying Ice Cream
MAN: [opens freezer and gets
some ice cream]
AB: [sticks his head into the freezer] So, armed with all this knowledge and you're still going to buy ice cream.
AB: It's okay. We all do. Okay, check out the fat content. Now, by law anything calling itself ice cream has to contain at least 10% milk fat. But that's a bare minimum, okay. The good stuff will always contain more. Check it out. It's there on the side panel. Second big thing is air. By law, ice cream manufactures can use 100% overrun. That means there's as much air by volume as there is ice cream in the carton. Here, you go weigh your half 'g' along with some of that discount stuff down the block. Go ahead. Check it out. Check it out. Check it out.
See, since high-end ice creams will never contain anything close to 100% overrun, they'll always weigh more than less costly brands.
AB: Pretty amazing, huh? Read the ingredient list. Go ahead. Look for things you'd see in home made ice cream: cream, eggs, sugar, stuff you can pronounce. Now, emulsifiers and fillers have names only a chemist could love. You know, polysorbate 80. I mean, what's that about? So, avoid them, okay?
All right. Well, I'm glad we had this time together. You have a good day, okay? Bye-bye.
Vanilla out sells Chocolate 3 to 1.
It isn't so tough to fathom General
Washington's little obsession. Just a single bite of the simplest
fruit ice, sorbet, sherbet, or ice cream is an enigma, a slap of cold
giving away to a loving hug of creaminess and textures morphing, flavors
releasing and overlapping waves and then ... [sigh] It's a memory. No wonder ice cream rates as the top preadolescent sensual experience.
We hope we've inspired you to dabble in the frozen arts yourself, in the privacy of your own freezer, of course. Until next time, this is good eats.
Visit us on the web at www.foodtv.com.
Last Edited on 08/27/2010