[Physics] Why would frozen sausages defrost faster in water

Question

My mom uses frozen sausages for a soup. She defrosts frozen sausages by submerging them in water (room temperature I believe). She claims this makes them defrost faster. She learned this from some article in a magazine and now swears by it. She is of no scientific background, so no accurate experiments have been made. Is there any physics why this might be true? Why would they defrost quicker in water? I cannot think of a reason why this would happen.

Moreover, she sometimes keeps the sausages wrapped in aluminum foil to keep them from absorbing moisture. Would this surely slow down the melting because of this extra layer?

Answer 1

I do exactly the same. It is a very effective way of defrosting food fast.

Compared to air water has a much higher heat capacity and a much higher thermal conductivity. That means heat flows from the water into the sausages much faster than it would in air and the water cools less than air would as it heats the sausages.

Aluminium foil has a much, much higher thermal conductivity that either water or sausage meat. Provided the foil is tightly wrapped around the food, so there isn't a large air gap between the food and the foil, wrapping the sausages in aluminium foil will have almost no effect of the rate of thawing. Any small gaps are quickly filled with water as the frost on the surface of the food melts.