biochemical tests Flashcards
what type of tests are biochemical tests
qualitative
what is the test for non reducing sugars ( sucrose)
it is the same as reducing sugars however first a dilute hydrochloric acid is added to the sample which is then neutralised by sodium hydrogencarbonate
what reagent is used to test for starch
iodine
what is used to test for reducing sugars
benedict’s reagent
what colour is a positive test for sugar
green, yellow, orange red in increasing concentration
what colour is a positive test for starch
blue-black
what does a positive result for lipids look like
a milky emulsion will form, the ‘milkier’ the higher the concentration
what colour is a positive result for proteins
lilac/ mauve
what are limitations of a proteins test
if the sample only contains amino acids or dipeptides, the result will be negative due to the lack of peptide bonds
NOTE
do your method cards !
