Warning - those of you who always stay neat and organized may find this strategy totally useless... but indeed it works for me...
I don't have a photo to show the effect. But I swear it works! I've seen quite a few online discussions on how to clean porcelain teacups. But to be honest, I didn't read most of them thoroughly... because... this problem just doesn't bother me much. Most of my frequently used porcelain teacups have layers of tea stain, lighter or heavier, always! There are few days of a year when they look bright white, and that's because my dear partner has cleaned them for me :-p
I've learned that baking soda is one of the best things for cleaning porcelain. That's what I use, very occasionally, when I need to pretend being neat and treat some guests with bright white teacups. But baking soda should be used with care and shouldn't be used to soak the porcelain ware. I remember when I was little, when my mom wanted to "deep clean" some dishes, she would soak them in baking soda water, and the dishes would eventually gain a "scrubbed" handing feeling.
Recently I used a teacup with heavy tea stain for red wine (I do this kind of messing-up very often...), didn't quite finish it, and left the cup there for a night (usually I am not that messy...). But then the second day, when I wash that cup with plain water (and I never use detergent for teacups), the wine stain and tea stain both came off, and I had a bright white cup in my hands!
So next time, if a porcelain cup is too heavily stained, I would use it for wine, and wait till the next day to wash it. Lazy people can always find a way out, haha!
I guess, it's because the tea stain is slightly alkaline, and wine stain is slightly acidic. So they perfectly neutralize with each other. Probably vinegar, cider or lemon juicy would do the same?
Announcement: A big box of Petr Novák tea wares (beautiful teapots, shiboridashi, teacups...) have arrived today! Most of them will be available in Life in Teacup online store soon. But before that, some special blog discount will be available. So stay tuned :-D
3 weeks ago