The invention relates to a method for analysing ingredients, in particular lipids and/or vitamins and biological material ingredients, to methods of using relevant organic solvents or organic solvent mixtures, and to a spectrophotometer for measuring biological material ingredients. It is proposed to treat the biological materials with at least one organic solvent which extracts the ingredients, to convert the bi ological materials to a solidified form during the extraction, with the result that a solidified sediment and a liquid organic phase as the supernatant are formed, and to examine the extracted ingredients in the supernatant.