While working on recipes for my cookbook *plenty* of aprons, towels and such required proper washing technique, took a minute to figure out a satisfying one.
Powder used was Premium Plus from Biokleen, which I find the best from what more eco-friendly laundry has to offer. It actually beats Tide, proven by my Partner's Grandma.
One scoop of detergent plus 1/4 cup of pure sodium percarbonate (Amazon) dissolved in near-boiling water with 1 cup of non-sudsy ammonia did the trick after a brief agitation and overnight soak. Toughest spots had been pretreated with Method's dish liquid.
In case of a front loader (I assume) I'd start the sanitize cycle with additives mentioned above, pause it mid-cycle (when the temperature is raised high enough)and let soak, maybe starting from time to time every hour or so to agitate the load a tad.
After the soak I'd let the load drain and start a new sanitize cycle again (with all the additives), letting finish; just to avoid soil redeposition effect, as well as clean whatever was left behind.
