EFFECT OF MAGNESIUM CARBONATE AND SODIUM PHOSPHATE ON THE EXTRACTION OF CHLOROPHYLL-LIKE PIGMENTS AFTER THERMAL PROCESSING OF SPINACH PUREE
Because buffers are important in maintaining green color in vegetable purees, a study was undertaken to determine if sodium phosphate and/or magnesium carbonate would effect extraction of some or all of the chlorophyll-like pigments in spinach puree and thus interfere with their analysis. Samples were prepared with and without addition of the above additives and pigment analyses were carried out for chlorophylls, chlorophyllides, pheophytins, and pheophorbides. It was found that addition of sodium phosphate and/or magnesium carbonate prior to blanching and processing caused chlorophyll b, pheophytin a, pheophorbide a, and pheophorbide b to be bound to some extent. Pheophytin b was unaffected Chlorophyll a, chlorophyllide a, and chlorophyllide b were present in such small quantities that no conclusions could be drawn about their extractability. This phenomenon is an important consideration in the analysis of chlorophyll-like pigments in buffered systems and also might supply a suitable means for removal of chlorophyll-like pigments from foods and beverages where the color they impart is undesirable.