Question

Which type of homebrewer is best for 8 ppm of dissolved oxygen in solution?

(a) Siphon sprays

(b) Whipping

(c) Splashing and shaking

(d) Pure air through a stone with an aquarium pump

I got this question by my school teacher while I was bunking the class.

This intriguing question comes from Estimating Oxygen Solubility topic in chapter Mass Transfer of Bioprocess Engineering

Answer 1

The correct answer is (c) Splashing and shaking

For explanation: Homebrewers have several aeration/oxygenation methods available to them: siphon sprays, whipping, splashing, shaking, pumping air through a stone with an aquarium pump, and injecting pure oxygen through a sintered stone. Pumping compressed air through a stone is not an efficient way to provide adequate levels of DO. Traditional splashing and shaking, although laborious, is fairly efficient at dissolving up to 8 ppm oxygen. To increase levels of oxygen, the carboy headspace can be purged with pure oxygen prior to shaking.