It follows your account's weight base measure: if it is KG the AI is asked for metric quantities (grams, kg, ml, litres); otherwise imperial (oz, lb, cups, tablespoons, teaspoons). The same rule applies to the ingredient lists produced by Generate Meals With Sprwt AI. Change it under Client Config, on the Theme: Kitchen tab, System Unit Weight (Metric vs Imperial) setting, if the units are wrong for your kitchen.