Question

Quasi – steady state in fed batch is when?

(a) Growth rate remains constant

(b) Dilution remains constant

(c) Growth rate changes variably

(d) μ remains constant

I had been asked this question in an interview for job.

My doubt stems from Fed Batch Culture in division Microbial Growth Kinetics of Bioprocess Engineering

Answer 1

Right answer is (c) Growth rate changes variably

Easy explanation: The major difference between the steady state of a chemostat and the quasi steady state of a fed batch culture is that μ is constant in the chemostat but decreases in fed-batch. However, in the genuine steady state of a chemostat, dilution rate and growth rate are constant whereas in a fed-batch quasi steady state they change over the time of fermentation.