|MadSci Network: Agricultural Sciences|
Hi! The simple answer is that a quantitative test is probably not possible at home. The normal reference test, called the Kjeldahl Nitrogen Determination, requires strong acid, special heating and distillation equipment. The more traditional protein assay tests like Lowry and Biuret require special regents and a quantitative spectrophotometer.
You might on a "limited" basis be able to find someone at the state university to do the test. Many "soil testing" labs can measure nitrogen, which as a rough estimate, can be converted to protein by using the N (in, for example, grams) x 6.25 to get the grams of protein. (There usually is a small charge for this service.)
I should mention that my guess is that if you have healthy chickens or other birds, that the egg protein composition will be very near that of commercial birds, and that the variation is probably due more to strain and weather differences than to an inherent difference between large and small scale operations.
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