Ruling on one who inhales the smell of food deliberately

There is nothing wrong with a fasting person smelling good
smells, from food, perfume etc, but he should not inhale bukhoor (incense)
or the steam coming out of the cooking pot because these have particles
which may reach his stomach. 

It says in Haashiyat al-Dasooqi (1/525): 

If the smoke of bukhoor or steam from the cooking pot reaches
the throat, the day must be made up… if it reaches it through inhaling
deliberately, whether the one who does that is the one who is making it or
someone else. But if one of them reaches the throat without him wanting it
to, then he does not have to make it up, whether he is the one who is making
it or someone else according to the correct view. End quote. 

Shaykh Ibn Baaz (may Allaah have mercy on him) was asked: 

Is it permissible to use perfume, such as putting on ‘ood,
cologne and bukhoor during the day in Ramadaan? 

He replied: 

Yes, it is permissible to use it, so long as one does not
inhale bukhoor. End quote. 

Fataawa Ibn Baaz, 15/267 

Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) was
asked: What is the ruling on a fasting person using perfumes during the day
in Ramadaan? 

He replied: 

There is nothing wrong with using them during the day in
Ramadaan and inhaling them, except for bukhoor, which should not be inhaled,
because it has particles which may reach the stomach, i.e., the smoke. End
quote. 

Fataawa Ramadaan,
p. 499 

It says in Fataawa
al-Lajnah al-Daa’imah (10/271): 

If a person puts on any kind of perfume during the day in
Ramadaan when he is fasting, that does not invalidate his fast, but he
should not inhale bukhoor and powdered perfume such as powder of musk. End
quote. 

The point is that simply
smelling food does not affect the fast, but one should not inhale the steam
from the cooking pot. 

And Allaah knows best.