ABSTRACT
The aim of this study was to evaluate nutritional composition of China chestnut seeds, Sterculia monosperma Vent. and analyze the physico-chemical properties of flour from the seeds. The results obtained on proximate analysis of China chestnut seeds, S. monosperma, revealed that they contained mostly carbohydrate (73.7% dm), followed by fat (12.0% dm), protein (7.8% dm), fiber (5.5% dm) and ash (1.0% dm). They have a relatively high content of potassium (12.3 mg g(-1) dm) following by phosphorus (2.30 mg g(-1) dm), magnesium (1.87 mg g(-1) dm), sulfur (0.88 mg g(-1) dm) and calcium (0.14 mg g(-1) dm). The fatty acids profile was found to be composed of mainly palmitic (42%) and oleic acids (34%), with general long-chain fatty acids the other significant component by mass (13%). Glutamic acid (17.4%), aspartic acid (12.5%) and arginine (12.5%) were the three major amino acid constituents. The purified seed starch was investigated for its morphological, starch content and physico-chemical properties, such as amylose content, swelling power, solubility and pasting properties. The starch granules were quite round, about 10-15 micron diameter and composed of more than 35% (w/w) of amylose. The pasting properties of flour from the seeds of S. monosperma revealed that gelatinization began at 72.6-73.2 degrees C and the maximum viscosity in the holding period at 95 degrees C was 633 BU. Interestingly and potentially of use, was that the viscosity at the cooling period was more than two-fold higher than that in the holding period.
