The answer should be written in two parts - a quantity and a unit code. If the unit specified by the respondent does not have a code, simply write the name of the unit (do not convert to other units on your own). Often times, the respondent might have difficulty recalling the precise quantity purchased in the past 4 weeks. This is to be expected. However, you should help the respondent arrive at an estimate if necessary - this can be done by asking how much of the food item is consumed on any given occasion, and then how often it was consumed in the past 4 weeks.