In this research study, preparations made of ground and shelled pea seeds (Pisum sativum) of Poa and Ramir variety were hydrothermally modified (the starch : water ratio was 1 : 2) at a temperature of 60 ºC, for 24 h. The preparations obtained were characterized by a high content of starch (i.e. more than 92 % in dry mass). The content of amylose in the starch was similar for the two varieties and amounted to 26.5 % (Poa) and 24 % (Ramir). The water holding capacity of starch of the two varieties was at the same level at a temperature of 60°C, whereas the solubility of Poa pea was higher than of Ramir pea and amounted to 10.3 % and 7.1 %, respectively. The increase in temperature to 80 °C caused the increase in both the solubility and water holding capacity. The starches studied were characterized by a rather low digestibility of 44.6 % as for Poa and of 36.8 % as for Ramir. The effect of hydrothermal modification of the annealing type applied was that the pea starch was additionally purified through decreasing the content of proteins and mineral compounds determined as ash. Additionally, it was found that the amylase fraction and the content of phosphorus decreased. This probably impacted the formation of new crystalline areas as a result of stronger bonds between amylopectin chains, and, finally, was a factor causing the real surface of starch grains, their water holding capacity and solubility to decrease at a temperature of 60 ºC and of 80 ºC. A considerable improvement was also found in the in vitro digestibility (> 2-fold) of the two preparations.
pea starch, hydrothermal modification, solubility, water holding capacity, digestibility