In my view, soda crystals are an essential part of laundering massage towels: firstly because the crystals help to lift massage oil out of the fibres, freeing up the detergent to do the cleansing work and secondly because the residue of oil can be a fire risk when the towels are placed in a dryer, on a hot radiator or even left in a car.
Method: fill a sink or bowl with hot water and stir in a couple of handfuls of soda crystals; soak each towel in the solution for five or ten minutes, agitating the towel so that the diluted crystals have a chance to permeate right through; squeeze out excess fluid and transfer straight to the washing machine; repeat for each towel. Then do a normal detergent wash: I am currently using Method Concentrated Laundry Detergent, which gives good results. (You can also add white vinegar to the rinse cycle if you wish)
The extra effort is worth it, because towels will last much longer and you will avoid the terrible rancid smell of towels that have a build-up of trapped oil in their fibres; you will also lower the fire risk particularly if you are using a tumble dryer!
Further advice on laundry can be found on the Dri-Pak website
Particularly in regard to omitting fabric conditioner and using white vinegar instead
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