The Open Food Science Journal

2008, 2 : 10-22
Published online 2008 April 10. DOI: 10.2174/1874256400802010010
Publisher ID: TOFSJ-2-10

The Possible Role of Starch in Oral Calcification: The In Vitro Formation of Hydroxyapatite is Regulated by a Combination of Protein and Mineral Content in Dietary Starch Flour

Saburo Hidaka , Yoshizo Okamoto , Suehiro Tsukamoto and Akiko Oishi
Department of Dental Hygiene, Fukuoka College of Health Sciences, 2-15-1, Tamura, Sawara-Ku, Fukuoka 814-0193, Japan.

ABSTRACT

The effects of twelve kinds of dietary starch flour, i.e. rice (non-glutinous and glutinous), wheat (soft, medium, and hard), barley (roasted), buckwheat (inner layer and straight), corn, sweet potato, kudzu, and tapioca on in vitro calcium phosphate precipitation were investigated using the pH drop method. The induction time was elongated by the addition of all of the kinds of flour. Although the rate of amorphous calcium phosphate (ACP) formation was not affected, the rate of transformation of ACP to hydroxyapatite (HAP) was either stimulated or inhibited by the different types of flour. The following observations were made: (1) When the lipid content below 0.2% (w/w), any of the types of starch had a stimulatory effect on the transformation of ACP to HAP. (2) When the lipid content around or above 1.0% (w/w), the value of the product of (protein content) ≥ (mineral content) seems to determine the effect of starch.

Keywords:

Amorphous calcium phosphate, calcium phosphate precipitation, dietary starch flours.