because the hot air mixes with air faster as the particles of the cold food are closed pack which don't allow the smell to mix in air

Why the Smell of Hot Sizzling Food Reaches You Several Metres Away but the Smell of Cold Food Requires Close Proximity
When it comes to the smell of hot sizzling food versus cold food, there are several factors that come into play that explain why the scent of hot food can travel much further than that of cold food.

Temperature and Volatility
- Hot food releases more volatile compounds into the air compared to cold food. When food is heated, the molecules in the food gain energy and become more active, leading to increased evaporation of aromatic compounds.
- These volatile compounds are what carry the aroma of the food, and when the food is hot, these compounds are released at a higher rate, resulting in a stronger and more noticeable smell that can travel further distances.

Diffusion and Airflow
- Hot food releases steam and other vapors that rise and disperse in the air, carrying the smell along with it. These vapors can be carried by air currents and spread over longer distances.
- On the other hand, cold food releases fewer volatile compounds, and these compounds tend to stay closer to the source of the food. Without the aid of heat to create steam and promote diffusion, the smell of cold food remains more localized and requires closer proximity to be detected.

Sensory Perception
- Our sense of smell is also more sensitive to warm or hot aromas compared to cold ones. Hot food releases more intense and complex aromas that are easier for us to detect from a distance.
- Cold food, on the other hand, may have milder and less distinct smells that are harder to detect unless we are in closer proximity to the source.
In conclusion, the combination of temperature, volatility of aromatic compounds, diffusion, airflow, and sensory perception all contribute to why the smell of hot sizzling food can reach you several meters away, while the smell of cold food requires you to be in close proximity to detect it.