Structure of Cooked Spaghetti of Durum and Bread Wheats
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English Slovak |
| Online Access: | http://www.viks.sk/chk/star_12_03_546_557.doc |
| Abstract: | Summaries. The structure of cooked spaghetti of durum and bread wheats was studied using low voltage scanning electron microscopy, and light microscopy applying different staining methods. Central, intermediate and external regions, and four zones along the external region of cooked spaghetti strands, were characterized in unprecedented detail. Changes in structure of starch granules from core to surface portrayed the successive stages in starch gelatinization, and possible starch retrogradation in the external region. Pronounced changes in shape of starch granules commenced in the intermediate region, while apparent internal changes dominated in the external region. Spaghetti of bread wheats differed from that of durum wheats by the larger size and higher extent of fusions and retrogradation of starch, and less amounts and continuity of intervening proteins. The significance of a high protein concentration for pasta production from bread wheats was emphasized. Furthermore, the relevance of a small size of the large starch granules was inferred. Conclusions. Scanning electron microscopy of fresh material of cooked spaghetti and light microscopy of stained sections, increased our knowledge regarding the induced structural changes due to cooking. The structural features across the spaghetti strand provided novel information on the changes accompanying starch gelatiniza-tion. This is expressed in the swelling of starch granules and appearance of voids around them, changes in the internal structure of starch granules, fusions between neighboring granules with consequent discontinuities in the protein matrix, and final starch deformation, segmentation and possible retrogradation close to the surface. In addition to the standard parameters comprising protein content and composition, and flour particle size, the size of the large starch granules might be of relevance to pasta quality. The bigger size of large starch granules in bread wheats apparently favors a higher extent of granule fusions and consequent discontinuities in intervening proteins which would lead to inferior pasta quality. Bread wheats with optimal standard parameters and with least size of the large starch granules might prove to be suitable for pasta production. |
|---|---|
| ISSN: | ISSN 0038-9056 |
