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As I've mentioned in another question, I'm attempting to make a large block of gelatin. Unfortunately, my first few attempts come out a bit amber in hue, using just water, sugar, gelatin and clear flavoring.

After some research, I found a video on making clear gelatin in which they:

  1. used a different brand of gelatin
  2. bloomed the gelatin in less liquid than I had
  3. added citric acid
  4. heated it for quite some time

I suspect that they also used a lower gelatin to water ratio. (I need this quite stiff, as it'll be an unsupported cube about 10 inches (25cm) on each side.)

In looking at their images, I think that there's still a little hue to their solution, but I'm not sure which of the differences are most significant to the process. Does anyone know?

  • I should also add -- after watching the video and reading some other articles, I heated back up my gelatin and held it at 180°F for about 30 min ... I think it cleared up some, but it's still darker than I'd like ... also, I'm using about 2TB of Knox gelatin per cup of water. I also have a canister of Great Lakes kosher gelatin if that would make a difference. – Joe Jan 22 '14 at 17:31
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    Is this something that absolutely has to be gelatin? In my experience gelatin is usually a bit yellowish without adding any coloring. If you can get away with using agar-agar though, it's much more clear (and can be made very stiff). – SourDoh Jan 22 '14 at 17:31
  • @sourd'oh : I wish I had known that before I started ... I'm trying to get this done for a contest on Friday, so I'd have today and tomorrow to try to source alternatives (which might be problematic for more rare items) – Joe Jan 22 '14 at 17:36
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    Agar is pretty easy to find at health food stores, if that helps. It's really easy to use and is much more stable than gelatin once it sets (and I think the flavor is also a lot more neutral). If you can't find it, I think the kosher gelatin might be your best bet, as it's usually made from fish (if I'm not mistaken). – SourDoh Jan 22 '14 at 17:42
  • @sourd'oh : blah ... all of the agar that Amazon has listed as 'prime elligible' that they claim will ship to me by Thursday if I order within (x) hours, when you go to the individual item pages they say it'll get to me by Friday. I might have to dig out the driveway to get to a health food store. – Joe Jan 22 '14 at 18:07
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You might also want to use a higher quality gelatin, like the one used for gelatin art. See this one: https://gelatinartmarket.com/products/gelatin-powder-280?variant=1455952961

Gelatin Art

  • I watched a lot of videos on it, but had only seen images of them in half spheres. (and this only an inch or two in thickness ... less for where the 'petals' are). I guess I could try again, as the competition is in January. (I technically won last year, but it was the day after multiple days off from a snowstorm, and I was the only entry). – Joe Oct 27 '16 at 2:03
  • Forgot to give a follow up -- yes, this stuff worked great, I didn't go for the 10" cube, but made a block about 10"x12"x3", and visibility was still pretty good in the longer dimensions. – Joe Apr 25 '17 at 12:31
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I've used konnyaku it's a japanese gel-type dessert you make from powder. it's crystal clear. it looks like solid water. it's rubbery as directed, but you might use more water or less powder to get the texture you want. here's a photo of what it looks like, but they've got fruit (?) in the gel that makes it look colors. http://i106.photobucket.com/albums/m255/hijackqueen/Cooking/konnyaku002.jpg

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After many, many tests, I have discovered a few things:

  1. Heating the gelatin for a long time is very necessary. I found 180°F (82°C) for 30 min would make sure that the gelatin was properly disolved, so that it would minimize the murkiness. (30 min was my minumum test, it might've been possible with less time)

  2. You need to pour the gelatin while it's quite hot. 170°F (77°C) was fine, but even taking it down to 160°F (71°C) resulted in a good bit of murkiness (likely introduced by small air bubbles when pouring; I might have had better luck with more careful pours, or using alternate means to move the liquid (eg, syringe)).

  3. You need to minimize any air bubbles. If you pour it in layers, slowly move a fork through the top to pop and bubbles. If you still have a few remaining after it's set, you can pour the hot liquid on the bubbles to remove them from that layer. (I used a spoon to deflect the pour to right near the wall of the container).

  4. Avoid flavorings. Alcohol-based extracts will make it more murky. (it clears up some after heating; it's absolutely horrible if you try mixing it in at the end) Oil based flavorings had no emulsifier, and would just separate out. (the best flavoring I could find was 'white cranberry' beverage (10% juice), but noticed there seemed to be variance over time in the color. (a bottle that I had in storage for a year was considerably more apple-juice like in color than a more recent purchase).

  5. Gelatin has better visibilty than Agar-Agar. Although Gelatin has a tint, the Agar isn't fully transparent when it sets, even after holding it for hours at temperatures just off the boil. (I was using an immersion circulator for heating, so I never took it to a full boil. Held it at 95°C (203°F) overnight, then tried a couple of hours at 99°C (210°F).

  6. You can't get clear, unmoldable jello in the scale that I was dealing with. You need to cut back the gelatin to about 1TB gelatin per 2c. of liquid for visibilty (albiet poor visibility). It's possible that it might set up sufficiently if given a week in the fridge, but you really need at least twice that to get it to firm up sufficiently at larger sizes. (note that it's fine for smaller items ... I used shot glasses for my tests, so thought I was going to be okay)

  7. no matter what you do, you can't set licorice laces in arches in jello. The heat needed from the pour causes them to collapse, even if you freeze them first, or set them in a layer of jello. (tried Agar too, but I had to mix it fairly week to keep it from being too opaque and it didn't set up enough to hold vertical; this might be related to my holding it at high temps for too long, though).

I never tested if citric acid had an affect, but I just don't think that I can pull off what I'm looking for in this scale. After 3 more catastrophic failures this year (on top of the 2 last year), I think I'm giving up on this project.

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    I did do it again, but only used translucent colored gelatin over a coconut milk panna cotta. Which leads to more lessons learned : 8. Don't use recipes for sugar roses to make pulled sugar arches. (it's too flexible, so sags on you within ~10 minutes.) 9. Pulled sugar will slowly dissolve if pushed into gelatin. (at least the too soft sugar that I was using) – Joe Oct 27 '16 at 2:11
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The gelatine is made either beef or pork. The beef is the yellow grains the pork is what you want for transparent it is a white grain. It took a lot of research to find this simple answer.

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    Ah ... I was using beef gelatin. (trying to keep it kosher for some of the people there ... but I see that was likely a mistake, especially as there was likely pork gelatin used in the boxed mix for the layer underneath. – Joe Jan 31 '17 at 12:49
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Gelatin in photography is never subjected to boiling temp as it loses its viscosity temps to melt - low bloom and high bloom gels are also different. Cowhide gels are for photographic emulsions. Porcine (pig) gels are the clearest.

The first extraction from a batch cow or pig is the highest bloom. Different temp and acids and another run leads to lower bloom. Blooms as low as 75; will melt on your kitchen table. A dissolved 300 bloom will melt at about 113. Porcine is used for clear gelatin capsules therefore you need a high bloom pig.

Agar agar you buy at Asian markets. It's shipped from Los Angeles to el, and in between. New York good price. 4/5 sticks in a clear package color clear, red and green sticks. Cut up to small pieces, just cover with water soak overnight. Get a slow cooker from Goodwill and bring solution up to medium heat or highest. A pan on a stove is not good. Don't burn or scorch; check just for a slight boil. Agar can be left heating until water is half gone. This is no problem, simply add more water. When finished, cover crock without free cloth no lid or condensation will fall back on agar. Set in refrigerator not freezer 45 to 70 will last a year.

Take out let rise to room temp them use crock again. I use both in my darkroom for making sub bases to hold gelatin on glass plates and negative and positive emulsions. You can read lots of info but exact procedures to work the magic is lacking in basic information.

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    I think there's useful info in here, but some of it's confusing. eg, "therefore you need a high bloom pig agar agar you buy at orental outlets" Is that two sentances? Because agar agar is from seaweed, not pigs. And I wish I had all of the recipies from my grandfather's (& great grandfather's) darkroom. – Joe Sep 13 '17 at 21:51

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