Lowry method determine the amount of protein in an unknown solution. They do this by measuring certain distinctive protein characteristics which involve UV absorbance. Protein assays enable biochemists to characterize one of the two defining properties of enzymes.
We should have a linear graph for absorbance versus concentration of gelatin. When the concentration of gelatin is increased, the absorbance recorded on spectrophotometer also increased. But from our finding, we found that graph does not linear. It is because these methods rely on the presence of readily oxidizable amino acids such as tyrosine, cysteine, and tryptophan there is a variation in response from proteins with differing amino acid content. Therefore it is advisable that the protein used for generating the standard curve be consistent from experiment to experiment. Likewise, an overabundance of the amino acids in relation to the assay reagents, as would occur with high protein level, will result in a loss of linearity of the assay. Besides the presence of bubbles also effect the result of the experiment.
For all eggs being tested, egg size was determined using effective diameter, as well as egg weight. In the grading process, eggs are examined for both interior and exterior quality and are sorted according to weight (size). Grade quality and size are not related to one another.
In this experiment, there are 4 types of egg tested, egg grade A, grade B, grade C and X or duck egg. From the table 2, we can see the egg grade A has concentration of protein 23.33 mg/L, egg grade B has concentration of protein 29.61 mg/L. While concentration of protein for egg grade C is 21.26, and X or duck egg has concentration of protein 27.30 mg/L. The grade B has the highest absorbance that recorded on spectrophotometer. It means that its protein content of egg grade B is the highest. While, the egg grade C has the lowest protein content.
If we compared the concentration of protein of egg grade A and X or duck egg, we found that the duck egg is higher than egg grade A. We can say that the protein content in duck egg is higher than the grade A. If we arrange the quantity protein in ascending order, egg grade C → egg grade A→ X or duck egg → egg grade B.
From our finding, the protein content are the highest in egg grade B. There is no difference in nutritive value between the different grades. Because our mind set grade A have the highest protein quantity. However, from this experiment we can conclude that the grade does not determine the protein quantity. Therefore, I will prefer egg grade B than grade A, C and duck egg because of its high content of protein.
