A comparison between the physico-chemical properties of tuber and cereal starches

• Published in: Food research international 2009-10, Vol.42 (8), p.976-982
• Main Authors: García, Nancy L., Famá, Lucia, Dufresne, Alain, Aranguren, Mirta, Goyanes, Silvia
• Format: Article
• Language: English
• Subjects: biofilm; Biofilms; Biological and medical sciences; cassava starch; Cereal and baking product industries; Chemical and Process Engineering; crystallization; Engineering Sciences; food grains; Food industries; food packaging; Fourier transform infrared spectroscopy; FTIR; Fundamental and applied biological sciences. Psychology; glycerol; grain products; heat treatment; Mechanical properties; packaging materials; permeability; plasticizers; scanning electron microscopy; SEM; Starch; Starch and starchy product industries; TGA; thermal degradation; water content; water vapor; waxy corn; X-ray; X-ray diffraction
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2009.05.004

Biofilms based on waxy maize and cassava starches (cereal and tuber starch, respectively), plasticized with glycerol were characterized through their crystallinity, dynamic-mechanical behavior (DMA), thermal degradation (TGA), moisture content and water vapor permeability (WVP). X-ray diffraction experiments show that both materials were mainly amorphous, with the waxy starch presenting a discreetly A-type X-ray pattern. Microscopic investigation of the cryo-fractured surfaces supported this observation. The glass transition of the glycerol-rich phase (measured by DMA) occurs at higher temperatures for cassava than for waxy maize starch, suggesting that the dispersion level of glycerol is higher in the former. TGA showed that maize starch has a slightly higher thermal stability than cassava starch, while glycerol interacts more strongly with the last one. The WVP was 18% higher in the case of the cassava starch film.