Effect of drying temperature on physicochemical properties of starch isolated from pasta
1999
Yue, P. | Rayas-Duarte, P. | Elias, E.
Semolina from four durum wheat genotypes (cvs. Ben, Munich, Rugby, and Vic) were processed into spaghetti that was dried by low (LT), high (HT), and ultrahigh (UHT) temperature drying cycles. Starch was isolated from dried pasta and unprocessed wheat and semolina references. Pasta-drying cycles had no significant effect on the amylose content of starches. Significant increases in enzyme-resistant starch were observed in HT- and UHT-dried pasta (2.27 and 2.51%, respectively) compared with LT-dried pasta (1.68%). Differential scanning calorimetry (DSC) gelatinization characteristics of pasta starches showed a significantly narrow range (T(r)), but no changes in onset and peak temperatures (T(o) and T(p), respectively) and gelatinization enthalpy (deltaH(1)) were observed. When compared with unprocessed reference samples (wheat and semolina), all pasta starches shifted to higher gelatinization T(o) and T(p), with narrow T(r) and no changes in deltaH(1). The second endothermic DSC peak indicated no increase in amylose-lipid complexation (deltaH(2)) due to drying cycle. Starches isolated from LT and HT pasta exhibited lower peak viscosities than those from UHT-dried pasta. Genotypes Ben and Rugby demonstrated higher pasting temperature and lower peak and breakdown viscosities than Vic and Munich.
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