supposedly pineapple changes the taste.
too much beetroot is meant to change the colour.
as does an over amount of coloured sports drinks.
not sure how long it takes but it meant to go by the amounts that you eat as well as time.
as in if you only eat a few grams of pineapple a day, it will take longer then eating it by the fistful morning, noon and night.
it depends if you want it to change really.
and consult your partner about it too -just in case they don't like the taste of what may be transferred downwards.