Can a Sorcerer multiclass use Metamagic on a Ritual Casting?

Question

I have a character who multiclassed from a Sorcerer into a Druid. She has the Subtle Spell metamagic, and has prepared the Purify Food and Drink spell via her druid spellcasting feature - this spell has the ritual tag. She is a guest at a feast, but some nefarious individuals are also present there. For a number of reasons* she wants to cast purify food and drink as a ritual, and spend 1 sorcery point to use subtle spell on this casting - can she do this?

To be more general, Can sorcerer-multiclass characters use Metamagic options on ritual castings from other spellcasting classes? I see nothing that would prohibit this**, but I want to make sure.

Relevant excerpts:

Subtle Spell: When you cast a spell, you can spend 1 sorcery point to cast it without any somatic or verbal components.

Druid Ritual Casting: You can cast a druid spell as a ritual if that spell has the ritual tag and you have the spell prepared.

* Wanting to avoid being poisoned, save her spell slots for a possible fight, and simultaneously not offend the hosts by insinuating that they would allow anyone being poisoned at their feast by noticeably checking.

** Apart from the awkward 10 minute pause before eating, but that can be done before the meal if the exact time of serving is known or controlled.

Answer 1

Yes, Metamagic can be used on ritual spells from any source.

Most metamagic options specify that you can use it "when you cast a spell [...]", and casting a ritual version of a spell still counts as casting the spell.

Certain spells have a special tag: ritual. Such a spell can be cast following the normal rules for spellcasting, or the spell can be cast as a ritual. [...] To cast a spell as a ritual, a spellcaster must have a feature that grants the ability to do so.

Casting a spell as a ritual just removes the use of the spell slot. If Metamagic required a sorcerer to be casting a spell using a spell slot, it would specify so.

Furthermore, the spell you affect with Metamagic can be cast from any source / spellcasting class feature. If metamagic could only influence sorcerer spells, each of the options would instead say "When you cast a sorcerer spell [...]", which does not appear in Metamagic; such wording does appear elsewhere in the class for reference, such as with Spellcasting Focus from the sorcerer's Spellcasting feature:

You can use an arcane focus as a spellcasting focus for your sorcerer spells.