PL
Celem pracy była ocena wybranych właściwości skrobi z komosy ryżowej uprawianej w Polsce w porównaniu do skrobi wyizolowanej z nasion komosy pochodzącej z Peru oraz z pszenicy. W skrobiach oznaczano podstawowy skład chemiczny, zbadano ich pęcznienie (SP) i rozpuszczanie amylozy (AML), synerezę, zdolność emulgowania (EC), właściwości termiczne i strawność skrobi in vitro. Różnice między skrobią z różnych komos były głównie wynikiem różnej zawartości amylozy – skrobia z komosy czerwonej o najmniejszej zawartości amylozy (3,3%) cechowała się najniższą temperaturą przemiany, najmniejszą synerezą oraz najlepszą zdolnością emulgowania. Skrobia z komosy uprawianej w Polsce miała bardzo słabą zdolność emulgowania, ale dużą stabilność żeli podczas przechowywania. Wyznaczone wartości przewidywanego indeksu glikemicznego wskazują, że zastępowanie skrobi pszennej skrobią z komosy w produktach poddawanych obróbce termicznej nie będzie powodowało obniżenia ich indeksu glikemicznego.
EN
The use of quinoa seeds for consumption can be hindered by the significant saponin content. These seeds could be used to obtain starch, but its properties depend on the seed variety, amylose content, and growth conditions. Therefore, the aim of this study was to evaluate selected properties of starch from quinoa cultivated in Poland as compared to starch isolated from seed originating from Peru and wheat starch. The starch was isolated from seeds of white (QW), black (QB) and red (QR) quinoa originating from Peru, and from seeds of the white quinoa grown in Poland (QWPL). Comparative material was commercial wheat starch (PS). Starch samples were subject to determinations of moisture, protein, ash, and amylose contents, as well as microscopic examinations. Swelling power (SP) and amylose leaching (AML) during heating of starch solutions, syneresis, emulsifying capacity (EC), thermal properties of starch using differential scanning calorimetry (DSC), and starch digestibility in vitro were also tested. The quinoa starches were characterized by very small granule size and large differences in amylose content (3.3–15.6% d.m.). These two factors determined the properties of quinoa starch. The small size quinoa starch grains have caused that it was rapidly digested in the native state and its predicted glycemic index (pGI) ranged from 86.6 (QWPL) to 93.1 (QW), while that for wheat starch 65.3. Due to the small size granules, quinoa starch also has emulsifying properties in contrast to wheat starch, but this property was dependent on other factors, among others, amylose content. The largest value of EC characterized QR starch (41.2) with the lowest amylose content (3.3%). The QR starch was characterized by the lowest transition temperature, low syneresis, but the greatest swelling power and leaching amylose indicating weak interactions (within the granule interior) between amylose–amylopectin chains. The QWPL starch was characterized by weakest emulsifying capacity, relatively high gel stability during storage, and lowest digestibility in the native state as compared to the other quinoa starches. The studies of digestibility of gelatinized starch showed that relative to native starches, the pGI value of starch from QB and from QR slightly decreased, but it was greater or at the same level as in wheat starch. Recorded pGI value indicates that replacing the wheat starch with quinoa starch in products subjected to heat treatment will not cause a reduction in their glycemic index.