Why does gelatin need to soften?

[rworange]

Couldn't decide if posting on the General or Home Cooking board was best, but was hoping that someone who might not read Home Cooking might have the answer.

I've continued my home-made jello experiments that I started a few months back.
http://www.chowhound.com/topics/315519

Every recipe says to sprinkle gelatin on liquid and soften from one to ten minutes.

OK, so I know for a fact that the time doesn't matter. Sprinkling one minute yields the same results as ten.

So that got me curious if it needed to be softened at all. As far as I can see, it doesn't.

I boiled two cups of juice, dumped in a package of Knox gelatin, stirred and put in the fridge. Didn't make one difference. It still jelled.

So what's that all about?

Everyone says soften, but no one says why and it doesn't seem to matter.

Another question before I have to throw a batch out ... why do you need hot water in the process? Why not just sprinkle on the liquid, stir and refrigerate?

So far, there is only one thing that seems to matter in making jello ... liquid to gelatin ... two cups of liquid to one packet of gelatin.

Too little liquid and you get jello squares. Too much liquid and it doesn't jell.

[babette feasts]

From McGee: granulated gelatin and sheet gelatin are given an initial soaking in cold water so that the gelatin network can absorb moisture and dissolve readily when warm liquid is added. If added to warm liquid directly, the outer layers of the solid granules can become gluey and stick neighboring granules together, even though these clusters eventually disperse.

So maybe soaking is not 100% crucial, just a simple step to avoid having to work out clumps later.

You need hot water because the gelatin does need some heat to actually disolve into your liquid. The melting temperature of gelatin is around 100F - I believe the exact temp depends on how and from what species the gelatin was extracted.

Surely you know that fresh pineapple, papaya, and kiwi contain protein-digesting enzymes that break the gelatin down and prevent it from setting.

More from McGee: other common ingredients have effects on gel strength
*salt lowers gel strength by interfering with gelatin bonding
*sugars (except for fructose) increase gel strength by attracting water molecules away from the gealtin molecules
*milk increases gel strength
*alcohol increases gel strenth until it becomes 30-50% of the gel, when it will cause the gelatin to precipitate into solid particles
*acids- vinegar, fruit juices, wine - with a pH below 4 produce a weaker jelly by increasing repulsive electrical charges on the gelatin molecules

And of course you can play with the ratio depending on if you want something solid (finger jello), softer and spoonable (like panna cotta served in a dish), or even a barely set sauce that you just don't want completely liquid on the plate - little gelatin can give it enough form to 'stand up'. A little gelatin will also bind up some of the water in sorbets and help prevent iciness (I sometimes do this with very thin sorbets like lemon).

Hope that helps.

[rworange]

Thank you so much ... especially for the extra info. Well, duh ... I should have dug my McGee out.

One thing I've found is interesting is that apple juice intensifies fruit flavor. A jello with one box of apple juice and one box of orange juice will taste more orange-y than two boxes of orange juice.

Someone asked early on why Martha Stewart used apple juice in a recipe. I didn't know at that time, but I suspect that it was to bring out the flavor of the berries in that jello. Even though apple is a high pectin fruit, it doen't seem to matter in terms of jelling more.

You are right about the clumping if you don't soften and just add to hot liquid. Stirring was enough to break it up.

Oddly enough sugar and alcohol hasn't noticeably changed the texture of the jello. Maybe it is not in a high enough ratio. My experiments in milk all ended with curdling ... tried for creamsicle with oj and milk.

And just for anyone who doesn't know, already it is only the fresh versions of fruits such as pineapple that prevent jelling. The canned versions have the enzyme broken down by processing and work fine. My favorite jello to make is with a can of crushed pineapple ... one cup of water with a packet of jello sprinkled on top ... in a saucepan bring one can of crushed pineapple to a boil and add to water ... good and simple.

Thanks again. I don't have to wonder anymore and have a lot more info about future batches and combos of ingrediants

[babette feasts]

You're welcome. That is interesting about the apple juice. Yes, McGee is wonderful. So are you using unflavored gelatin and making your own flavors? For creamsicle, you could infuse milk with orange zest - not the same fresh flavor, I know. Or do layers, an orange infused milk gelatin topped with an intense orange layer (let the first layer set before pouring on the second, mostly cooled batch). Or maybe try making the jello with orange, cool it until it almost starts to set, then stir in milk or half and half so you don't have the heat factor increasing the chances of curdling. Or use yogurt, buttermilk, or creme fraiche for the dairy, you wouldn't want to heat those either but you can safely add a lot of acid to them. (Well, you can heat creme fraiche but not yogurt, unsure about buttermilk)

[Eat_Nopal]

Hey RW,

If you are experimenting with gelatine, this link has one for you to try:

http://www.chowhound.com/topics/show/...

Cheers!