TL;DR: likely because demand was too low to sustain commercial distribution
Barring any relationship to a specific historical incident, it's very difficult to find out why a specific food is no longer commercially produced. In the absence of specific reasons, we can see a number of contributing factors as to why grape preserves would have gone off the ...
I don't know for sure if it is the same enzyme naturally that naturally occurs in apples, but there is a commercial product called NovoShape that serves this purpose. It is a pectin esterase. You can find it in small quantities at Modernist Pantry: http://www.modernistpantry.com/novoshape.html
I found a study done in Korea in 2010 that said pectin can replace shortening in cookies and therefore, they concluded other baked goods. The ideal amount was 30% replacement saying the texture was actually better and the cookies were more moist. They don't recommend going higher than 30% as a 40% difference changed the structural integrity in a "negative" ...
I received the following response from Bonne Maman in France
Dear Mr. XXX,
Thank you for contacting Bonne Maman®. We are always happy to hear
from our consumers. You are the reason Bonne Maman is such a
Bonne Maman is owned by Andros SNC, a privately owned, family run
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There are plenty of high-sugar-content sweets that use gelatine, so it would be a reasonable substitute, but won't match the texture that pectin would normally provide in a pate de fruit or jam.
I don't know of any recipes using agar-agar that are designed for long-term storage, it is more often used in desserts, and again has a very distinctive (slightly ...
There's no problem adding pectin later in the process, you just have to be careful how you do it depending on the form. Powdered pectin can glob up if you just pour it in, mixing it with a bit of water or cooled marmalade from your pot will prevent this. Pectin sugar or liquid pectin mixes can be added without any issues.
The thing is you shouldn't need to ...
Without seeing the recipe and procedure, it is hard to say if the seeds are necessary, there are many recipes for Seville orange marmalade that don't call for the seeds, and some that do. There is a good chance that they aren't essential to the recipe, that being said:
There is pectin in the seeds of citrus, but there is no need to grind or chop them for it ...
All gelling agents work only under certain conditions. You need to be in the working range for:
Pectins are more sensitive than gelatine, working in narrower ranges. Also, not every pectin is active in the same range, the main difference is between HM and LM pectin.
You can try if gelatine works with your recipe, ...
I've made grape, blackberry, elderberry, pear and apple jams and jellies, as well as combinations of those fruits, for years with Sure Jell dry pectin. I sometimes stir in spices like cinnamon for grapes and blackberries, nutmeg for pears and apples, and even lavender flowers or mint. Elderberries grow wild in our area. I use the instruction sheet in the box....
...NadjaCS seems to have already answered this question above, but here's a link to a website which explicitly gives a recipe for a pie-melon pie using diced and flavored pie melon. It also has a link to an antique recipe for what appears to be candied pie melon slices; I'm sure you could use those slices in place of the base for some other fruit pie.
It could also possibly be because the modern varieties of grapes commercially grown for eating do not make a good jelly or jam.
Having made jam with a variety of grapes I have found that most of the grapes we buy as table grapes make a fairly ordinary jam whereas if you can get hold of older cultivars, grape jam/jelly is an amazing preserve.
Three other possibilities are (I think #3 is most likely):
salt-tolerant mucilage-producing bacteria. I don't know of a species, but it's possible.
pectinase happened. Pectin is activated with heat as you said. But pectin can be enzymatically broken down into simple sugars and acids. Over time, as water evaporated through the corroded seal, the sugars ...
It is possible that you have precipitated the proteins to some extent by the salt concentration (known in biological fields as "salting out"), which might produce a gel-like blob, just like cooking egg-white does.
You can indeed also precipitate proteins with sugars (e.g. here), though it is more commonly used for extraction of organic acids (e.g. ...
For what it is worth, in case you want to make your own grape jam.
The recipe calls for basically four things: grapes, sugar, lemon, butter. And as I have gotten a lot of recipes off of SeriousEats.com, I figure this might be worth a look.
Check it out here.
Unfortunately, syneresis is a byproduct of an agar gel. It is the nature of the molecular structure formed in the gel. This can be desirable, especially when using agar as a clarifying agent, however, not good for your jam. According to www.molecularrecipes.com, you can prevent this by replacing 0.1 - 0.2 percent agar with locust bean gum. I see you've ...
You can use a chilled plate to test your batch before canning it next time. Pectin does not firms up with time, just temperature.
I would suspect that the watermelon juice has made your jelly too dilute, and you'll need to boil your jelly down further.
No, you can't.
Different pectins set under different conditions. Some require calcium, others require a high percentage of sugar. All have their own optimal pH range.
When a recipe is optimised for one type of pectin, other types won't set properly. Normally, you cannot substitute in any direction.
The linked question from Jolenealaska's comment ...
Yes, you can.
I have recently successfully cooked a batch of apple jam with only apples, sugar and water. The trick to extract enough pectin in order for the jam to solidify is either to cook them for a very long time or let the fruits sit for a night or so.
I just added the diced apples to a boiling sugar-water mixture (about 1:1), cooked them briefly and ...