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Gelatin


foodietraveler

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I just googled silver 160 bloom gelatin leaves and turned up the not-so-astonishing fact that silver gelatin leaves at a weight of 2.5 gr are 160 bloom and gold at 2 gr are 200 strength. Knox gelatin, which we all know and love, is 225. I thought gelatin could be subsituted weight for weight, but not being real quick with the numbers, I can't finesse this. I've been using silver, and find that I need to use more, but one wonders if there is a way to come up with a handy dandy conversion ratio thing.

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If you don't like math, I don't think you'll like my answer, but here goes anyway...

From The Age (Austrialian newspaper) I found this formula:

Weight (Bloom 2) = weight (Bloom 1) x square root (Bloom1/Bloom2)

This is also mentioned (although not as simply) here.

C1(B1)½÷(B2)½ = C2

Basically it works like this:

If the Knorr gelatin is your known mass at 1 unit of mass and 225 bloom, it is #1.

and

the Silver gelatin is your unknown mass at 160 bloom, it is #2.

Weight (silver) = weight (Knorr) x square root (Knorr bloom / silver bloom)

Weight (silver) = 1 unit x square root (225/160)

Weight (silver) = 1.19 unit

So, for every 1 unit (gram or ounce) of Knorr that is called for, you would use about 1.2 units (gram or ounce) of the silver gelatin.

The simple answer: to go from Knorr to Silver gelatin, just multiply the weight by 1.2

I hope I haven't confused you too much. I know, it's ugly.

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Actually that's very helpful, if I can just sit with it for a while. I love arcane formulas once I get the hang of them, Bernoulli's priniciple, Avogadro's number, Langmuir's hypothesis of raindrop collisions, Foucalt testing, that kind of thing.

I was taught to make up a gelatin solution of 1 oz of gelatin to 5 oz of water. One oz of this solution should gel 1 lb of mousse or whatever. If 10 sheets of gelatin equals an ounce, then 1.6 sheets should equal one oz of gelatin solution. But this is assuming the bloom strengths are equal.

So basically if I would use an ounce of Knox, I need 1.2 oz of silver leaves. If one oz of gelatin solution has .17 oz of gelatin in it, 1 part in 6, then multiplying that by 1.2 gives me .204, so I need to replace one oz of solution with .25 oz of silver leaves, just to be on the safe side. That comes out to 7 grams plus a teeny fraction. At 2.5 g each, and I'm going to check that in the morning, that means I can start with 3 leaves to gel a lb, and see how it comes out, and maybe work my way down. I've been using the 1.6 to 1.8 range and had a passionfruit mousse come out a little loose yesterday. That make sense?

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So basically if I would use an ounce of Knox, I need 1.2 oz of silver leaves

Exactly.

As you say, in this case, your 1oz gelatin to 5oz water would be use 1.2 oz (about 34g) silver gelatin.

Following your calculations further, the 1oz of solution would be replaced by .204oz silver gelatin plus 1oz water.

Rounding up from .204oz to .25 and then rounding up the number of leaves to a whole number may leave you with a more solid mousse than you would ideally like, but I agree that you'll probably end up with between 2 & 3 leaves per pound, so 3 is a reasonable starting point.

I'm glad that the formula didn't scare you off. I came across it by chance just yesterday in a search for something else.

I hope that this works for you.

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I typically make a mousse in a big batch and store it in the ubiqitous fish bucket, rather than making it and using it immediately. If it comes out a little stiff that's ok, because I usually assemble a mousse cake by piping the mousse onto cake rounds and it squishes a little coming out of the tip. It will hold up better, I hope, if it's a little firm to begin with. I'll make some tomorrow and we'll see. I had been using mycryo to make mousse cakes but it was so hit or miss that I wanted to use gelatin because I know I can have mousse cakes on hand more consistently.

That was a very interesting article but the scientific link nearly put me to sleep.

thanks for the help with this.

Edited by McDuff (log)
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You're welcome. I'm glad I was able to help, it was just really good timing.

I have to admit that I just scanned the scientific article to try to make sure that I was getting agreement between the two formulas. I had the same reaction as you to it. :biggrin:

I'm interested to know how your experiment goes. I hope you'll post your findings.

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I bloomed three sheets of silver leaf gelatine in water, drained it and squeezed it as dry as I could, then melted it, and drizzled it into 1 lb of 36% cream flavored with 1/8 cup florida crystals and a little vanilla as it was whipping around in the 5 qt mixer.This was almost the last thing I did before leaving work, but it had set nicely when I last checked it. I don't like the cream, it doesn't whip or hold as nice as 40%. I don't work again till Wednesday and it's in a bowl marked Test do not use, so we'll see what it's like after 48 hours.

Edited by McDuff (log)
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The whipped cream experiment was a success. Three sheets of gelatin per one pound and it held up all week. My boss tasted it and said it wasn't too bouncy. I'm going to make lemon mousse and raspberry mousse tomorrow. It will be equal parts of puree, pastry cream and whipped cream, as it needs to be easy enough for that mechanic on an icy night in Peoria.

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O.k. you guys I don't think I followed this completely.

I get that:

Knox (dried gelatin) is the strongest gelatin at 225

gold is 200

silver is 160

But can you simplify the math conversions, please? I can't do it on my own............

Then later on as a seperate issue/topic McDuff you mention that 3 sheets of ?silver? sets 1 lb of cream.......is that correct? But when you make your mousse........aren't you looking to set your puree with the gelatin, not the heavy cream? Wouldn't you be looking to find out how much gelatin sets 1lb of puree instead of 1 lb of heavy cream? Assuming that the whipped cream and the pastry cream are stable enough on their own (not needing any gelatin to set). Is that correct? So you don't account for extra gelatin to set the whipped cream or pastry cream?

And wouldn't different purees require slightly different amounts of gelatin to set them? 1 lb of lemon juice to 3 sheets of gold gelatin wouldn't set like 1 lb of mango puree to 3 sheets of gold gelatin.

I hope that made sense............what am I missing here...........? sorry.......

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Wendy,

If you are working with a recipe that calls for a specific weight of a specific gelatin (often Knorr powdered gelatin), you can use this equation to substitute a gelatin with a different Bloom value for the one called for in the recipe.

Weight (Gelatin A) = weight (Gelatin B) x square root (bloom Gelatin B/ bloom Gelatin A)

Or, in this case,

Weight (silver leaf gelatin) = weight (Knox) x square root (Knox bloom / silver bloom)

McDuff knows that it takes 0.20 oz of Knox powdered gelatin to gel 1 lb of whipped cream (based on his previous experience), but wants to use Silver leaf gelatin instead.

From the manufacturer's information, we know that:

Knox = 225 bloom

Silver = 160 bloom

For McDuff's application, to convert from oz Knox to oz silver, the formula is this:

Weight (silver leaf gelatin) = weight (Knox) x square root (Knox bloom / silver bloom)

Weight (silver leaf gelatin) = 0.20 oz x square root (225/160)

Weight (silver leaf gelatin) = 0.20 oz x square root (1.40625)

Weight (silver leaf gelatin) = 0.20 oz x 1.185854

Weight (silver leaf gelatin) = 0.237 oz

Weight (silver leaf gelatin) = 0.24 oz (rounded)

to convert from ounces to grams, multiply by 28.35

0.24 oz x 28.35 grams/oz = 6.80 grams

To get the number of leaves required -

If the gelatin leaves weigh 2.5 grams each, divide 6.80 by 2.5 to determine how many leaves are required.

# of leaves = weight req'd / weight per leaf

# of leaves = 6.80 / 2.5

# of leaves = 2.72 leaves

So, to replace 0.2 oz of Knox gelatin, McDuff would have to use 2.72 silver gelatin leaves. He chose to round up to 3 silver gelatin leaves for convenience.

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For convenience (and probably the sanity of a few mathphobics :wink: ) I've put together a conversion list based on these bloom values:

Knox powdered gelatin is 225

gold leaf gelatin is 200

silver leaf gelatin is 160

Remember - this is by WEIGHT. The first gelatin listed is the known value.

In the first conversion, 0.5oz of Knox would be equal to 0.5*1.19 = 0.595, or approximately 0.6 oz of Silver gelatin.

Knox x 1.19 = Silver

Knox x 1.06 = Gold

Silver x 0.84 = Knox

Silver x 0.89 = Gold

Gold x 0.94= Knox

Gold x 1.12 = Silver

Hope this helps a bit!

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For convenience (and probably the sanity of a few mathphobics  :wink: ) I've put together a conversion list based on these bloom values:

Knox powdered gelatin is 225

gold leaf gelatin is 200

silver leaf gelatin is 160

Remember - this is by WEIGHT.  The first gelatin listed is the known value. 

In the first conversion, 0.5oz of Knox would be equal to 0.5*1.19 = 0.595, or approximately 0.6 oz of Silver gelatin.

Knox x 1.19 = Silver

Knox x 1.06 = Gold

Silver x 0.84 = Knox

Silver x 0.89 = Gold

Gold x 0.94= Knox

Gold x 1.12 = Silver

Hope this helps a bit!

Thanks! But, what about when a recipe says use 3(specific number no matter) sheets of gelatin and you just have powder?

How much does a "sheet" weigh, especially when you don't know whether the recipe was based on silver or gold (or any of the others referenced in the article you linked to?)

I've got the rest of the math down -- just don't have any sheet gelatin!

Cheryl, The Sweet Side
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Hi Sweetside,

I should add a caveat here - I have never worked with sheet gelatin, only Knox, so this is all based on the mathematics & the formulas given.

From the web:

1 Sheet Silver gelatin - 160 bloom, 2.4g to 2.5g

1 Sheet gold gelatin - 200 bloom, 2.0g

1 Envelope Knox gelatin - 225 bloom, 7.0g

Silver to Gold sheets -

1 silver sheet is approximately equal to 1 gold sheet, based on the following conversion:

Silver to Gold conversion

2.5g silver x 0.89 = 2.225g gold

= 2g gold (rounding down) = 1 sheet

Unless you're dealing with large quantites, or a very delicate application, I would think that rounding down by this amount should not be an issue. Someone with more experience, please correct me if I'm wrong.

If a recipe says to use X number of sheets (and doesn’t specify type or weight), and you only have powdered, then I think you have to make a bit of a guess. For example –

Recipe says use 3 sheets, & you only have Knox.

3 Silver sheets = 2.5g x 3 = 7.5g

Silver to Knox conversion is:

Silver (g) x 0.84 = Knox (g)

7.5 x 0.84 = Knox (g)

6.3 g = Knox

3 Gold sheets = 2.0 x 3 = 6.0g

Gold to Knox conversion is:

Gold (g) x 0.94 = Knox (g)

6.0 x 0.94 = Knox (g)

5.64g = Knox

You would have to use about 6g (or a bit less than one envelope) of Knox.

Generally from what I’ve found on the web, 4 sheets of gelatin are considered equal to one envelope of Knox, but as I mentioned, I am far from an expert.

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I've worked with both just enough to know that even when the recipe says three sheets, it may not work out quite right the first time... But, at least knowing the weights and approximate conversion, I can now test recipe components as I go along adjusting to whatever I will "always" use.

At least a silver sheet more or less equals a gold sheet...

Thanks for all your help!

Cheryl, The Sweet Side
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O.k. you guys I don't think I followed this completely.

I get that:

Knox (dried gelatin) is the strongest gelatin at 225

gold is 200

silver is 160

But can you simplify the math conversions, please? I can't do it on my own............

Then later on as a seperate issue/topic McDuff you mention that 3 sheets of ?silver? sets 1 lb of cream.......is that correct? But when you make your mousse........aren't you looking to set your puree with the gelatin, not the heavy cream? Wouldn't you be looking to find out how much gelatin sets 1lb of puree instead of 1 lb of heavy cream? Assuming that the whipped cream and the pastry cream are stable enough on their own (not needing any gelatin to set). Is that correct? So you don't account for extra gelatin to set the whipped cream or pastry cream?

And wouldn't different purees require slightly different amounts of gelatin to set them? 1 lb of lemon juice to 3 sheets of gold gelatin wouldn't set like 1 lb of mango puree to 3 sheets of gold gelatin.

I hope that made sense............what am I missing here...........? sorry.......

I'm calculating the amount of gelatin needed according to the total weight of the mousse. We've been using 36% heavy cream lately and I hate it, it gets really soft right away, and by tomorrow, is leaking. I'll have to go back into my stuff from school to see if the amount of gelatin in Bavarois is only to set the anglaise, or the entire thing including the whipped cream.

As far as using lemon juice in a mousse, I'd be more likely to turn it into lemon curd first, add the gelatin while it was hot, then cool it and fold in the whipped cream. That's why I mix the puree with an equal amount of pastry cream. When I come up with a formula at work I have to be sure that pastry people of varying degrees of skill throughout our pastry program at the earthy crunchy groceria will be able to duplicate it without making themselves crazy.

There are so many mousse cakes in our product list, and some of them are as simple as puree added to whipped cream, not for me thank you, or one that a lot of people use but I have never tried, a white chocolate ganache that is allowed to cool overnight, then whatever cocoa butter or fat that is floating on top is skimmed off and the rest of it is whipped to thicken it, but it comes out really sweet. Adding the puree to pastry cream gives a mousse base that is as close to a Bavarian base in consistency as you can get without the trouble of cooking an anglaise. I have a thing about mouthfeel. Puree and whipped cream, there's nothing to it..I want to have some roundness in the mouthfeel, if you know what I mean. It needs to be more than a one-dimensional flavor thing.

I never got to the mousses today as matzoh crunch turned out to be more of a priority.

As far as how much to use when you only have powder, I think you can pretty reliably count on .16 oz setting a pound of mousse. I don't know what that is in teaspoons, but I think that one envelope of Knox is .25 oz. A box of 4 envelopes is listed as 1 oz. cook's illustrated weighed a bunch of envelopes and compared the weights to the volume measurements and found a significant discrepancy. I'll see if I can find the article, if I can stay awake tonight.

Edited by McDuff (log)
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  • 5 weeks later...

My problem is converting from TEASPOONS of powdered gelatin to SHEETS of gold. All of the wonderful conversion tables on this site deal with grams or ounces. My recipe for vegetable terrine calls for 3 teaspoons of powdered gelatin and I only have gold sheet gelatin. Should I assume that each sheet is approximately equal to 1 teaspoon of powdered?

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My problem is converting from TEASPOONS of powdered gelatin to SHEETS of gold.  All of the wonderful conversion tables on this site deal with grams or ounces.  My recipe for vegetable terrine calls for 3 teaspoons of powdered gelatin and I only have gold sheet gelatin.  Should I assume that each sheet is approximately equal to 1 teaspoon of powdered?

No, still go by weight. 1 teaspoon of powdered gelatin weighs 2.33 grams. Each Tablespoon weighs 7 grams.

Cheryl, The Sweet Side
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  • 9 months later...

I'm about to purchase some sheet gelatin online and am wondering whether to go with gold or silver.

I understand that differences in bloom strength and that I can substitute one for the other by adjusting the quantities (weights). Most of the pastry recipes I work with tend to be from either European or Japanese sources.

Are silver or gold sheets more commonly used in professional kitchens? Or is there no "standard"?

I should clarify that the gelatin is for home use, but many of my recipes are from professional kitchens (Herme's books, CakeChef, etc.).

Edited by sanrensho (log)
Baker of "impaired" cakes...
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sanrensho, either silver or gold are pretty standard. the only gelatin that (at least in my experience) isn't so standard is bronze. the bronze seems to be the heaviest (strongest) that i've come across.

i would say that in the professional kitchens i've worked in, silver is probably what i've used the most.

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  • 10 months later...

I've never worked with gelatin, because I've never been able to find a source of kosher gelatin. I now have a source, but when I was asked what mesh size and bloom strength I wanted, I was stumped.

Any advice? I want to use (and sell) it for marshmallows, mousses . . . And I only want to order one type.

Thanks.

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Thanks Lior. Since posting I've ordered a case of fish gelatin. I'm still interested in getting some of the beef gelatin though, so if you do know the size/weight, that would be great!

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  • 2 years later...

using the calculations i found on this thread + another gelatin one, my recipe calls for 1 sheet of gelatin (and doing the calculations its 2g so i see its a gold sheet). i did the math and came across 1.88g of knox powdered gelatin. my question is this--how much water need i bloom the gelatin in? even if you have a basic ratio in ounces i can drop it down but i've always just followed the recipes and those guide me but when using powdered gelatin i've just got no idea on the basics of blooming it

Danny

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  • 1 year later...

Last night I made a panna cotta and used, for the first time, coconut milk as an ingredient. I tried to dissolve the gelatine in the coconut milk, but the results were poor. The (powdered) gelatine just sat atop the milk and didn't soften, and when mixed into the milk and warm cream mixture, endend up with a number of lumps and clumps. Is gelatine and coconut milk somehow incompatible? BTW, I used a light coconut milk. Might I have had better results with regular coconut milk by using the thinner, watery portion to dissolve the gelatine and adding the thicker cream later? Thanks!

Edited by Shel_B (log)

 ... Shel


 

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