Page 62 - Analytical method for food addtives

32 Analytical methods for food additives

Reference 2 4 8 10

% NaCl solution and slight excess of NH 4 OH was added
% acetic acid in chloroform. Diluted nm. % acetic acid in chloroform. nm
% alcohol added to ground sample to extract colour, left overnight to precipitate
Combined petroleum ether extracts were washed with NH 4 OH and acidified with
to filtrate. Transferred to separating funnel and extracted with petroleum ether.

In presence of SnCl 2 annatto produced a purple stain
mL 10 % acetic acid in chloroform. Absorbance read at 505 and 474 mL 5 g to 200 Separation by reverse-phase C18-TLC using acetonitrile–THF–0.1 mol/L oxalic acid PAS was employed to determine the content of annatto via the intensity of an absorption peak compared with the absorption standard samples with a

g to 200 Diluted 1 in 10 with chloroform. Absorbance read at 503 and 473 Measurement of visible absorption spectra using scanning densitometry medium levels of dye contents in commercial products

Principle of method 80 proteins, filtered, evaporated, 25 CH 3 COOH. Oil-soluble annatto as bixin: 0.1 1 in 10 with 3 Water-soluble annatto as norbixin: 0.1 Clean-up with C18 cartridge. 1 2 (7:8:7) as solvent system. 3
Summary of methods for annatto extracts in foods

Macaroni products Commercial annatto formulations seasoning products

Matrix Foods Commercial

Table 5.1 (a) Method Colour reaction Spectroscopic RP TLC/scanning densitometry Photoacoustic spectrometry (PAS)