Carrageenans in the meat industry: detection using microscopic methods

Carrageenans are used in the meat industry primarily as stabilisers and binders and belong to the group of additives with the code E407. Three types of food carrageenans (κ-kappa, λ-lambda and ι-iota) were analysed using light and electron microscopy in this study. The individual types of carrageenans were analysed in the form of a loose powder. Samples for analysis under a light microscope were stained with Lugol-Calleja, Toluidine Blue and PAS-Calleja. PAS-Calleja was adjudged to be the most suitable staining for detection of κ-, λ- and ι-carrageenan on the basis of the intensity of colour and the size of the stained area in individual fragments of carrageenans. Images obtained by a scanning electron microscope indicate the morphological differences in structure between ι-carrageenans and κ- and λ-carrageenans. Cooked hams with 1% added κ-, λ- and ι- carrageenan were also examined under a light microscope. Differences in the localisation or spatial arrangement of individual types of carrageenan were found in this study.