Question

Cell death in solids is more effective than liquid.

(a) True

(b) False

The question was posed to me by my school principal while I was bunking the class.

My query is from Sterilisation in section Reactor Engineering of Bioprocess Engineering

Answer 1

Right choice is (b) False

Explanation: If the liquid contains contaminant particles in the form of flocs or pellets, temperature gradients may develop. Because heat transfer within solid particles is slower than in liquid, the temperature at the centre of the solid will be lower than that in the liquid for some proportion of the sterilising time. As a result, cell death inside the particles is not as effective as in the liquid. Longer holding times are required to treat solid-phase substrates and media containing particles.