[Sca-cooks] Query about verjus...urgent!!

[Stefan li Rous]

Back on Dec. 6, Thorvald quoted this recipe:
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"216. Green Verjuice [Sauce].
Take sorrel including the stem, steep in some other verjuice, strain [through
cheesecloth], and add a bread crust so that it does not turn. (A 1490 printed
edition quoted by Pichon et al., p. 194.)"
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Any idea what this green verjuice would "turn into"?

How could adding a piece of bread crust keep this from happening? Why the crust and not the non-crust area?

Perhaps the idea is to soak up some kind of oil, to keep something from happening?

Thanks,
   Stefan

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THLord Stefan li Rous    Barony of Bryn Gwlad    Kingdom of Ansteorra
   Mark S. Harris           Austin, Texas          StefanliRous at austin.rr.com
**** See Stefan's Florilegium files at:  http://www.florilegium.org ****