Rather a minority opinion, can you name any apart from coffee that meet these conditions?
It doesn't matter if any one herb/fruit/vegetable is a good source of both Ascorbic acid and Polyphenols or not. You can use a mixture where one herb/fruit/vegetable is rich in Ascorbic acid and the other is in Polyphenols. E.g. Amla or Broccoli with Thyme or Rosemary.
With added phenidone or ascorbate the edible foodstuff may act as a secondary developer , regenerating phenidone, or as a primary developer ,apparently being regenerated by ascorbate. The edible foodstuff surely complies with what is commonly called a developer in these cases too.
Perhaps I wasn't clear. If the edible stuff is able to develop film satisfactorily on its own without needing an additional developing agent, then there is nothing to argue against it. But it appears that, with the possible exception of instant coffee, no other edible stuff can develop film satisfactorily.
Now, some edible stuff do have Ascorbic acid and can work as a weak developer. Such a food stuff can plausibly make a potent developer when used with additional Ascorbic acid. In such a scenario I can simply use the requisite amount of Ascorbic acid instead of attempting to supplement the natural Ascorbic acid in the edible stuff with the synthetic one.
It is also plausible that a food stuff rich in Ascorbic acid can also work in conjunction with Phenidone. If this pairing works well without needing additional Ascorbic acid then fine. But if it needs additional Ascorbic acid despite the use of Phenidone, then again I can simply use requisite amount of Ascorbic acid and Phenidone instead of trying to supplement.
Now, consider edible stuff that are rich in Polyphenols. They seem to invariably need Ascorbic acid to get going. It is not clear how much of developing is due to Polyphenols vs Ascorbic acid. Hence I suggested the Thyme proponents to do a simple test in the other thread.
Hope this is more clear.
