This has happened to me so many times on committees, and yes, it is assumed that it is a woman's job to take the minutes (and organise the coffee, book the rooms, any basic practicalities) My response would probably have been 'why are you asking me?', whereupon I would have got all the flannel about 'you're so good at it, you are more reliable' etc, which of course probably true!
One committee I was on consisted of seven male members and two women. We were all chairs of local organisations of equal merit, yet it was assumed the women would act as secretaries for the committee. When I held my ground, either no minutes were taken, or they never appeared. I made it very plain to those higher up in the organisation that secretarial support should be provided, and the response was 'well why don't you do it?'
I hope the younger generations are more likely to share roles, I gather future official forms will no longer even ask for your gender!