Mash is the basic form of prepared feeds. If the mill has a pelletizer, it can be made into pellets and then, those broken pellets can be crushed into crumbles. If the feed isn't tainted or gone bad, it shouldn't be the source of the off taste.
The form or texture of the feed, being unimportant and merely a preference of the flock keeper, shouldn't be a factor.
Prepared mash, pellets or crumbles should constitute the vast majority of their feed intake. Free ranging pasture birds can find a lot of their own feed, but still need some prepared feed. It is highly unlikely that feed will alter the flavor of your eggs. If your eggs are tasting off, suddenly, I'd suspect a large amount of "tossed" feed items such as an overdose of those tomatoes or some other strong flavor item.
Experiment. Feed from a different bag of feed for a week. Don't feed anything "tossed" that may be suspect. You'll have to narrow this down.