You can use enzyme detergent--biological for my friends in the UK-- on linen correct? I know it can "eat' wool and silk. But I think it can be used on linen and rayon. Am I correct or delusional?
Correct. The enzymes digest proteins, which is why they are bad for wool and silk, which are animal fibers.
But if you're laundering pure linen flax, you may need to use very hot water and some care if the fabric is fine or delicate or old.
Also you should consider if your fabric is OK with added optical brightening ingredients, or not. Old fabrics were not treated on the bolt as new ones are and when exposed to detergent prodents with OBAs included can get splotchy looking from the adde flourescent dyes. New fabrics, of course, were treated and need the OBAs to continue to look bright.
I wash my white linens in 195- 205 F degree water, with a profile raise in heat from tap cold to main wash temp. I add an extra rinse and hang to dry. Of course they need to be ironed, very damp, with a hot iron or mangle.
Thank you liriodendron that was very helpful!