Pâte de Fruits (Fruit Paste/Fruit Jellies) (Part 2)

[MelissaH]

Would using a slow cooker with the lid off work? I know a lot of people successfully make apple butter that way without worries.

[Bentley]

Further to the discussion of piping PDFs, I found this picture on Kate Wesier's instagram feed.  From the way the PDF looks, my guess is that she is letting the PDF cool completely then perhaps blitzing it with a little more fruit puree before piping.  

 

 

 

https://www.instagram.com/p/3zGBBjAt1W/?taken-by=kateweiserchocolate

 

Edited June 28, 2016 by Bentley (log)

[ChocoMom]

Diana B....Thank you for posting the pic and conversations about PDFs!   Pre-fire, I had made Raspberry PDF several times using Shott's Raspberry-Wasabi duo--- and loved it!   Had to beat the heck out of it while cooking. Set up beautifully. 

 As I've mentioned on other threads, you all are so incredibly talented , knowledgeable and inspiring!   Your enthusiastic embrace of trying, testing and experimenting reminds me why I loved this type of craft so much!  I am beginning to have a hard time containing myself- as I await to get into the rebuilt house and shop!  Thank you for igniting that excitement again! 

[Jim D.]

Bentley,

I am very interested in what Kate Weiser might have done.  Have you seen any other information on this?  I was confused by earlier discussion in this thread about when to "blitz" the PDF, whether straight from the pot or after it has set (I have never tried the latter so don't know if it would come out as a smooth product).  Kate Weiser's is certainly smooth-looking, but it seems to me that adding fruit purée after everything is done would dramatically decrease the shelf life.  I am thinking that cooking to a lower temp, then blitzing might get a texture that can be piped.  Like you, I hate the extreme sweetness of many PDFs, but there does not seem to be a way around adding all the sugar and still getting a decent shelf life.

[Bentley]

Jim - Beyond the pictures on her instagram, I haven't seen any more info about her technique.  I did email her about it, but did not get a response.  

Here is another pic from her instagram.  It's her key lime bonbon which has a key lime PDF.  The piping bags are an older pic, so she has clearly changed formulas as it's no longer a red color.   I was really hoping to hear from her about her technique, but she was either too busy to respond or it's a state secret.     Please note that all images come from here:  https://www.instagram.com/kateweiserchocolate/

 

As for adding puree, I don't think it would take very much to get to a pipe-able consistency.  Just a small amount should be enough for the food processor to achieve a good paste.  Would have to do the shelf life tests to see the effect.  I suppose you could also use a small amount of alcohol to thin it, but that could probably affect the taste.  

 

 

https://www.instagram.com/p/BGXFpj1AtzX/?taken-by=kateweiserchocolate

 

And here's a pic of her Strawberry Basil bonbon in the making.  It's strawberry PDF and basil ganache.  Interesting to see the texture of the PDF here:

 

https://www.instagram.com/p/oYyfGigt70/?taken-by=kateweiserchocolate

 

Vs the texture of the PDF in the finished bonbon:

 

https://www.instagram.com/p/moWpDtgt7Y/?taken-by=kateweiserchocolate

 

And here's a picture of a lemon PDF that looks to have a very smooth and fluid consistency:

 

https://www.instagram.com/p/loV-Tegt1u/?taken-by=kateweiserchocolate

Edited June 28, 2016 by Bentley (log)

[sarah72]

I'm really interested in the pipable "gel" PDF. I saw something (maybe on this board) about blitzing the PDF with something like 10% additional puree, but I'm with Jim on worrying about what this would do to shelf life as I can't see the set PDF dissolving into the puree enough for the sugar to preserve it. I've tried just lowering the amount of pectin I use and not cracked it yet. The other thing I thought of was to not cook it as far but again this might cause shelf life problems.

[gap]

The technique I have used is to let the PDF set. Then blitz it with a small amount of alcohol to loosen it (which wont affect shelf life). We used an alcohol which "paired" with the PDF so the taste wasn't noticeable.

[Jim D.]

Bentley,

Thanks for those enlightening photos.  The texture she has achieved is just what I am looking for.  Now if only she would reveal her secrets.

 

Gap,

Thanks for that technique.  Adding fruit purée would be nice, but alcohol sounds like a great solution, and as you say, would not affect shelf life.  I suppose that if no alcohol exists that works with a particular PDF, vodka could always be used.  One question:  Do you cook the PDF to the usual temp or take it off sooner?  If the latter, do you think this affects shelf life?  It would seem that as long as the full amount of sugar is used, all would be well, but I'm not sure about that.

 

I'm going to do some experimentation in the next couple of months and see what I can come up with, measuring the Aw each time.  Now if I can just find an inexpensive purée to use.

 

The following observation is completely irrelevant to the topic at hand, but I was intrigued that Kate does not clean the colored cocoa butter from her molds, at least not before those photos were taken.  I am always reluctant to get the colors in the melted chocolate as one scrapes the molds.  I guess if you are rich and famous, you don't have those concerns--there's always more chocolate!

[Tri2Cook]

I think I remember Heston Blumenthal using what he called a pipeable PdF in the Fat Duck book. I'd have to dig out the book to be sure, it's been a while, but I think what he was calling a PdF in that scenario was actually made using gellan. I have no idea what that would mean in terms of water activity and shelf life, those are probably not major concerns for what he does, so this is probably completely irrelevant.

[Bentley]

So I was doing some research, and I came across a recipe from Valrhona that called for the PDF to be piped into a bonbon.  The recipe called for the PDF to be cooked and set, then put in a food processor with some Absolu Cristal, a glaze made by Valrhona.  The ingredients for Absolu Cristal are listed as water, sugar, glucose syrup, pectin, carageenan and citric acid.  

 

I wonder if you could just add a little corn syrup (and maybe a little bit of water) to the PDF to get a similar same effect.  You get a liquifier without adding much water and should have little effect on shelf life.   

 

(and BTW Jim, I have seen in other posts by Kate that she generally does clean the excess cocoa butter from the molds before filling them).

Edited June 28, 2016 by Bentley (log)

[gap]

5 hours ago, Jim D. said:

Gap,

Thanks for that technique.  Adding fruit purée would be nice, but alcohol sounds like a great solution, and as you say, would not affect shelf life.  I suppose that if no alcohol exists that works with a particular PDF, vodka could always be used.  One question:  Do you cook the PDF to the usual temp or take it off sooner?  If the latter, do you think this affects shelf life?  It would seem that as long as the full amount of sugar is used, all would be well, but I'm not sure about that.

 

Cooked to the normal temperature. Let it set and cool. Then blitz. When we made large chocolates (eg., large bars or domes that were 5cm diameter etc) we didn't add the alcohol. You could still pipe the blitzed PDF. When we were piping into smaller chocolates then we added the alcohol to help it settle into the cavity. From memory, it wasn't a lot of alcohol we added.

[Bentley]

I experimented this weekend with blitzing the PDF in a food processor with an additional amount of corn syrup as a liquefier.  I had decent success as I was able to pipe the mixture into the molded shells. I would like to thin it slightly more so that it flows into the shells and can settle flat.   The problem I had was that I killed my food processor.  The PDF was so thick and sticky that it caused the food processor to jam up and overheat.  It was actually smoking!  But anyways, behold the mango PDF with white chocolate coconut ganache with a hint of lime .

 

 

 

 

[Jim D.]

Bentley,

Sorry about your food processor.  Maybe you could use liquor (as recommended by gap) to thin the PDF.  So how does the finished product taste?  How is the sweetness level (I would assume the PDF part is on the rather sweet side since you added corn syrup)?

 

I like your shell decoration.  Do you mind telling how you did it?  And what sort of brush did you use for the white dots and the yellow streaks?

[Bentley]

On 7/4/2016 at 3:22 PM, Jim D. said:

Bentley,

Sorry about your food processor.  Maybe you could use liquor (as recommended by gap) to thin the PDF.  So how does the finished product taste?  How is the sweetness level (I would assume the PDF part is on the rather sweet side since you added corn syrup)?

 

I like your shell decoration.  Do you mind telling how you did it?  And what sort of brush did you use for the white dots and the yellow streaks?

It didn't take very much corn syrup to get to a pipeable consistency.  There is so much sugar and corn syrup in the PDF to begin with.  I didn't really notice any additional sweetness.  I would like to experiment with using alcohol to thin it out.  I could have maybe used a coconut rum in this case.  

 

The shell was done with a spatter of white cocoa butter done by running my fingers across the bristles of a toothbrush, then a splatter of yellow made by shaking a paint brush.  Then a finger swirl of a light green, then airbrush half red and half darker green. 

Edited July 6, 2016 by Bentley (log)

[Jim D.]

An interim report on my further efforts to get a pipeable and not-too-sweet PDF:

 

I used Pomona's pectin for the first batch.  This pectin requires much less sugar than the traditional method and cooks for only a few minutes.  No question, it produces a delicious product--the essence of strawberry in this case.  After 10% framboise was added, it was pipeable and still delicious.  Here comes the "however" in this experiment:  The Aw reading of the PDF (before and after the brandy was added) was 0.95.  If we are going for a fairly low Aw, this is not an acceptable reading for a bonbon to be stored for 2-3 weeks.  Still, if you are making a dessert and need a PDF to be served soon, I think Pomona's is the way to go.

 

Second I made a traditional PDF with apple pectin, using Ewald Notter's recipe.  Even though I cooked it to the recommended temp, it was too firm (I don't have a refractometer), but I added 10% brandy, then used an immersion blender on it.  It came out pipeable, and the Aw was 0.67, a big difference from effort #1.  But here is the "however" in this experiment:  The strawberry taste was muted, the color was a dark red, and the product was very sweet--much like strawberry jelly that is over-sweetened.  I do realize this is what PDF traditionally tastes like, but it does not look like the pictures from Kate Weiser, with their vibrant color.

 

Meanwhile I came across an exchange I had on The Chocolate Life about this whole topic.  The person responding sounded quite knowledgeable about shelf life issues:

 

Quote

 

In many states and per the FDA's food safety rules, jam and jelly / fruit syrups should have a pH < 4.0 and or an aW < 0.8 - 0.85 to be regarded as a non-hazardous food stuff....

 

According to the experts, in certain situations with some foodstuffs the relationship between total moisture content and or aW is not necessarily directly predictive of shelflife.  According to the reference materials I have seen, for jams and fruit syrups <0.8 aW is the level necessary to stop most moulds and bacteria such a S. Aureus.  Fruit jams (e.g. your pate de fruit layer?) may be such that halophilic bacteria could grow even at just aW 0.75. (hence pH adjustment is typically necessary for ensuring food safety).   Did you add acid during production e.g. citric acid with the pectin?  When water activity of a food stuff like a gel is likely not a good predictor of shelf life or even protection from microbiological spoilage, a shelf life study and or challenge trial with the formulation to determine food safety /spoilage may be needed.  Plus, in a two layer product one with a component with relatively high moisture content (gel - pate de fruit into ganache?) there may be some water migration, which can both change texture and also allow acquired free water to promote spoilage in another fraction with an initially low aW.  I've seen a thin layer of cocoa butter sometimes suggested to prevent migration between layer confections.

 

 

I am intrigued by the pH discussion (that in jelly-like substances, it is crucial, more so than water activity).  I just checked the Aw reading of a sample of commercial apricot preserves (Bonne Maman brand, to be precise), and it was 0.81--better than my Pomona's effort but not great.  I think most purées can take quite a lot of lemon juice/citric acid, so there is a possibility of lowering the pH of the PDF.  Meanwhile replacing some of the sucrose with something like dextrose or sorbitol (as suggested by the writer mentioned above) might lower the aW reading.

 

I don't have a pH meter, so I guess that should be the next purchase.  From what I have read, they are rather finicky to use.  Any suggestions for one?

[MelissaH]

How precise do you need to be with your pH measurements? You might be able to get by with pH paper instead.

[Jim D.]

From what the person said (in the quote above) the reading should be below 4.  As I understand it, the pH strips are fairly accurate up to 4, but of course if my jelly is well above 4, I would need some accuracy in a higher range.

[Jim D.]

I have come across an article by Michael Laiskonis about PDF and its high sugar content:

 

Quote

Sucrose is overwhelmingly the bulk sweetener of choice for pâtes de fruit, with the addition of some glucose to both inhibit crystallization and slightly reduce overall sweetness. I occasionally see invert sugar used in small amounts as well. Added sugars will also fluctuate slightly based upon the amount of sugar supplied by the fruit itself. Part of what makes pâte de fruit boring is that because of the need for high solids content (sugar), most of the potential flavor is obscured by sweetness. To this end, I’ve been playing around with sugar alcohols and even low DE maltodextrin [1. Here, DE refers to “dextrose equivalence.”] to reduce sweetness, with the end goal of perhaps approaching what one might even call a “savory” pâte de fruit. There may be limits to how much sucrose can be replaced with other sweeteners, but I hope to discover just what those limits are.

 

And he provides a very helpful chart of facts about various sweeteners.

[MelissaH]

You can get different pH papers that are good for different ranges. So if you think your pH is "well above 4" and you want to know how far above, you might consider using this paper: https://www.morebeer.com/products/ph-paper-46-62-beer-vial-100-strips.html

If you want to get a general idea of where you are, use a wide-range paper to start, and then use a narrower range paper (in the appropriate range) to get more precise.

Some pH meters use probes that can be fragile, and that need to be stored soaking in a buffer solution. These are analytical lab–grade instruments, possibly more than you need. If you don't think you're going to need to do this often, I'd probably start by getting a selection of test papers, since you can buy a lot of paper for the price of a meter. Alternatively, if you live near a college or university, try contacting their chemistry department to see if you can find a cooperative professor who already has a suitable instrument.

[Jim D.]

Melissa,

Thanks for those helpful tips on pH paper.

[keychris]

12 hours ago, Jim D. said:

The Aw reading of the PDF (before and after the brandy was added) was 0.95.

 

Did you (or anyone else) have a reading on PDF made in the traditional method?

[Jim D.]

Yes, I mentioned that in the description of my second PDF (a traditional one):  After adding alcohol, the Aw was 0.67 (a few hundredths lower before alcohol).  Even if one allows for the fact that I boiled off more water than I should have (resulting in a too-firm PDF), the reading is certain to be in an acceptable range.

[keychris]

hah, I read those post twice and didn't see that! thanks

[Jim D.]

I have spent more time experimenting with Pomona's pectin for PDF and have some interesting results for those who might happen to share my current obsession with PDF:

 

As stated previously, using homemade strawberry purée (made in the food processor from thawed frozen strawberries) and following the Pomona's instructions, with nothing added and no reduction of the purée produced a water activity reading of 0.95 (I am striving for a reading of <0.86).

 

Reducing the purée by half before making the PDF, with no other changes, gave 0.94.  This was a major surprise since I expected that boiling off so much water (and strawberries have a lot of it) would produce a significant change.

 

Reducing the purée and adding extra sugar at the end (1/2 the original amount called for) produced 0.88.  Clearly a move in the right direction.

 

Reducing the purée and adding an equivalent amount of invert sugar at the end produced 0.91.  Again, a surprise since invert sugar is supposed to be quite hydroscopic.

 

Reducing the purée and adding the extra sugar plus powdered sorbitol equal to 10% of the weight of the PDF produced a reading of 0.68.  Sorbitol lived up to its reputation.  Perhaps it was more effective than invert sugar because it contributes more solids whereas invert dissolves into the strawberries, but that's just a guess.

 

As for the taste:  Reducing the purée obviously masks the fresh strawberry flavor to a significant degree, but because Pomona's requires only a couple of minutes of extra cooking, it isn't as major a loss as with traditional PDF.  I did not detect a significant change in sweetness with the added sugar or with the sorbitol (I know many people don't like it, but aside from other considerations, I did not get any taste from it).

 

Since my first observation above is that reducing the purée did not make a major difference, I did one more batch without reducing the purée.  At the end of the cooking time (which was just a couple of minutes in all) I added an extra amount of sugar equal to all (not half) of the original amount called for, so I am doubling the sugar, and again added 10% sorbitol plus a teaspoon of lemon juice to counteract the added sugar (we are still quite far from the amount of sugar called for in a traditional PDF).  The Aw reading this time was a very encouraging 0.65.  The taste is the best (aside from the original with no extra sugar at all).

 

I am reluctant to say "eureka" at this point.  My purée had a lot of body because of the included fruit, and the method may not fare so well with something like a commercial frozen purée that is more like juice.  Since I was pleased at the final result, I will continue experimenting and see if the method can be extended to those other types of purée.  I have some kalamansi in the freezer that I don't use very often and will give that a try.

 

I haven't mentioned the pH of the PDF since I don't yet have a way of checking that, but the final PDF was still sweet enough that I think a lot more lemon juice/citric acid/tartaric acid could be added to reduce the pH to an acceptable level for safety.

 

I remain puzzled at Kate Weiser's pipeable purées (see photos earlier in this thread), especially the vibrant colors.  Could they possibly be PDF?  When she starts shipping again (at the end of the summer), I may have to purchase a box to see what I can determine.

 

I would welcome any thoughts.

[Jim D.]

The results of further experimentation with PDF using Pomona's pectin, both using the idea of adding extra sugar and 10% sorbitol by weight at the end to reduce water activity:

 

Kalamansi:  The aW reading was 0.57.  This was my first attempt with a purée that is more like juice (and the Pomona's recipes make adjustments for that--though having a thoroughly jelled product is not crucial when the plan is to use an immersion blender on the PDF), so I was pleasantly surprised at the low reading.  The taste is another matter:  Not that it doesn't taste like kalamansi, but I neglected to read Boiron's ingredient list so did not know that it is 100% fruit (no sugar at all).  After recovering from a serious case of mouth pucker, I realized that this is probably good news:  adding enough sugar to make it palatable would only help keep the aW reading low.

 

Orange:  Again the aW reading was 0.57.  I used frozen orange juice concentrate (no sugar added).  The final taste reflects a bit of that cooked taste that frozen juice has (because it is cooked, I assume), but it's good.  A little orange zest (either left whole then removed before the pectin sets or finely grated and left in--the latter would be my preference) might perk it up quite a bit.  So I added some grated zest and also a few drops of lemon juice to cut the sweetness.  The flavor was greatly improved, but this change resulted in an aW reading of 0.69.  Instead of adding lemon juice at the end, I could have added it when the PDF was still cooking or could have used powdered tartaric or citric acid, which would not have added any liquid at all.