Question

In the protein analysis, what’s the purpose of digestion and how the sample was digested?

Answer 1

Protein is derived from Greek word proteios meaning first. Protein are the polymers of amino acids.

The purpose of digestion is to break down the bonds that hold the polypeptides together & convert them into simpler molecules such as water, CO2 .

The sample was digested by Kjeldahl method.

Food sample to be analysed is weighed into a digestion flask & then digested by heating in the presence of H2SO4(oxidising agent to digest the food), anhydrous sodium sulphate(speed up the reaction by raising the B.P) & catalyst such as copper , mercury(speed up the reaction). Digestion converts any nitrogen in the food into ammonia & other organic matter to CO2 & H2O. Ammonia gas is not liberated in acid solution because ammonia is in the form of NH4+ which binds to the sulfate ion & thus remains in solution.

N(food) = (NH4)2SO4