DRYING STARCH NATIVE YAM Renata Duarte Almeida

DRYING STARCH NATIVE YAM
Renata Duarte Almeida, Maria Elita M. Duarte, Leila de Sousa Nunes, Mario Eduardo R. M.
Cavalcanti Mata, Anastácia M. M. C. Nóbrega. Federal University of Campina Grande - UFCG,
Rua Aprígio Velozo, 882, Bairro Universitário, 58429-140 Campina Grande, Brazil.
Starch is a product of great nutritional and industrial importance which is widely distributed in
various plant species. In order to be marketed starches should have water content of up to
14.00%. This research was conducted with the objective of to study the kinetics of drying of
native starch obtained from the yam varieties of São Tomé (Dioscorea alata) and Da Costa
(Dioscorea cayennensis) through adjustment the mathematical models of Page, Verna and
Henderson and Pabis to the experimental data. The drying of the product was performed in an
oven with air circulation at 30, 40 and 50 °C for period of 24 hours. After each drying could be
observed that the yam starch São Tomé dried at 30, 40 and 50 °C had a water content equal to
17.97, 10.35 and 6.87% (w. b.), respectively, while for starches of yam Da Costa these values
were 16.47, 9.95 and 6.64% (w. b.) after the drying. With the results obtained, it can be
concluded that due to high water content of starches extracted from yams varieties Sao Tomé
and Da Costa dried at a temperature of 30 °C are not recommended for marketing, unlike
starches dried at temperatures of 40 and 50 °C and that the mathematical model Page, with
coefficients of determination higher than 99%, was the one that best described the drying
behavior of the starches from both species of yam.