Can I coarsely crush coriander put into a muslin bag and add it to the keg?

What's the best means to sanitize?

IMO I dont think you will gain much orange flavor from cold steepin/ spice hopping with coriander. it will just taste spiced.. it must be added in the last minutes in the boil to be effective.
If you decide to try it, munch on a few seeds, that will give you a good indication of what flavor you'll be imparting to your beer

So which is it lacking - Orange Flavour or Coriander?

If it's coriander you feel it is lacking (and I applaud you for wanting *more* coriander - yum!) then you should be able to "dry coriander" (i.e. dry hop( it like you suggested. The feremented beer in the keg along with lacking O2 should keep any nasties at bay, but to play it safe, I'd soak them in some cheap vodka or grain alcohol before adding them to the keg. You might get a bit of an oil slick on the top surface but that should only appear in the last couple of pints, if at all....

Sounds like you are on the right track....

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You could always make an orange tea (orange peel and water) and blend to your liking.

Coriander is what gives it the orange flavor, IMO.

+1

The wife loves it and I tried it again (once the Balvenie wore off) and it does taste nice, but I think a bit more coriander would help it. I used the Peretto Postulate and used about half of the spice I originally intended to.

I just cracked up some coriander and man it smells awesome. I am prolly going to do the vodka/teaball/oil slick combo..

Be sure to make the recipe update in your system.... so you don't miss it next time...

Good thinking J.... I prolly would have forgotten!

Yeah, well I have to disagree with corriander is the only ingredient adding "citrus flavor/orange flavor".
Jamil Z did a write up on Belgian wits in the July/August '07 issue of BYO where he states that the best way to add citrus flavor is with fresh zest. I TOTALLY agree. The dried curacao stuff only bitters the beer. Corriander definitely has it's place - but the recipe JZ put forth calls for 43gm of freshly grated citrus zest - that's more than 4 whole average sized oranges! Got this one in the tail end of fermentation right now - it's putting out major citrus perfume.

You need curacao orange for wit, they sell it at my LHBS.


Richard

Didn't mean to imply that it's the only way, just the traditional way.