Toxicological evaluation of some food additives including anticaking agents, antimicrobials, antioxidants, emulsifiers and thickening agents WHO FOOD ADDITIVES SERIES NO. 5 The evaluations contained in this publication were prepared by the Joint FAO/WHO Expert Committee on Food Additives which met in Geneva, 25 June - 4 July 19731 World Health Organization Geneva 1974 1 Seventeenth Report of the Joint FAO/WHO Expert Committee on Food Additives, Wld Hlth Org. techn. Rep. Ser., 1974, No. 539; FAO Nutrition Meetings Report Series, 1974, No. 53. MONOSTARCH PHOSPHATE Explanation These starches contain phosphoric ester groups, mainly attached to C-6 and to a lesser extent to C-2 and C-3 and of the glucopyranose units (Gramera et al., 1966). They are made by the use of alkali orthophosphates, phosphoric acid, or alkali tripolyphosphate. BIOLOGICAL DATA BIOCHEMICAL ASPECTS In vitro enzymatic hydrolysis of monostarch phosphate by wheat alpha-amylase was compared with unmodified wheat starch. No difference was noted in the rate of production of reducing substances. The metabolic behaviour of the phosphate radical in starch phosphate was studied in vivo by comparing the distribution of p32 after oral administration of labelled starch phosphate to rats, with that from either labelled orthophosphate or pyrophosphate. The percentage activity excreted in urine and faeces over 48 hours as well as the percentage activity retained in liver, kidney, blood plasma and bone showed no significant difference for the three types of phosphate examined. The phosphate moiety of starch phosphate probably behaves metabolically like any other ionic phosphate (Laboratories of International Minerals & Chemical Co., 1955). Comments: An adequate metabolic study has shown that the modification does not affect the digestibility of this starch. Whatever the manner of attachment of the phosphate groups may be, their metabolic disposition after digestion follows the same pathways as free orthophosphate or pyrophosphate. This material is not to be regarded as toxicologically different from native starch of the same botanical origin provided the phosphate content is limited. EVALUATION Estimate of acceptable daily intake for man Not limited.* * See relevant paragraph in the seventeenth report, pages 10-11. REFERENCES Gramera, R. E., Heerema, J. & Parrish, F. W. (1966) Cereal Chem., 43, 104 Laboratories of International Minerals and Chemical Corporation (1955) Unpublished report to American Maize Products Co.
See Also: Toxicological Abbreviations MONOSTARCH PHOSPHATE (JECFA Evaluation)