[Sca-cooks] aisel was New 'invention' of medieval food?

[Sharon Palmer]

>(cider vinegar was called aisel).

 From OED, nothing in this definition says the word is specific to 
cider vinegar.
eisell, n.
Etymology:  < Old French aisil, aissil < late Latin *ac?tillum, 
diminutive of ac?tum vinegar. Obs.

   Vinegar.
c1160    Hatton Gosp. Mark xv. 36   Fylde ane spunge mid eisile.
c1160    Hatton Gosp. John xix. 29   ?a stod an fet full aisiles.
?c1225  (1200)    Ancrene Riwle (Cleo. C. 6) (1972) 296   ?is 
eisil??urch fulle? mi Pine.
a1240    Wohunge in Cott. Hom. 283   Nu beden ha mi leof?aisille.
a1300    Earliest Compl. Eng. Prose Psalter lxviii. 22 [lxix. 21] 
In mi thriste with aysile dranke ?ai me.
138.    Antecrist in Todd 3 Treat. Wyclif 133   Crist tasted eysel; 
and ?ei nolden non but goode wynes.
c1420    Pallad. on Husb. viii. 134   In this moone is made Aisel squillyne.
c1450    J. Myrc Instr. to Par. Priests 1884   Loke thy wyn be not eysel.
1528    T. Paynell tr. Joannes de Mediolano Regimen Sanitatis Salerni 
sig. Liiijv,   Sommer sauce shulde be verieuse, eysell, or vineger.
1552    R. Huloet Abcedarium Anglico Latinum,   Ysell, acetum.
1557    Primer, XV Oos F iv,   I beseche thee for the bitternesse of 
the Aisell and Galle.
1604    Shakespeare Hamlet v. i. 273   Woo't drinke vp Esill, eate a Cr

It strikes me that this is very close to the German "essig"

Ranvaig