Three under-utilised sources of starch from the Andena region in Ecuador. Part II. Rheological characterisation.

Summary, in English

The dynamic rheological behaviour of Arracacha xanthorriza white carrot), Canna edulis (achira) and Oxalis tuberosa oca) starch gels were studied in strain-sweep mode. The starch was diluted with water to cover particle volume fractions of 1–3. The starch suspensions were heated at 89 8C for 30 min, and their swelling power and amylose leaching were measured. C. edulis showed the highest swelling power and particle rigidity (the elastic modulus, G0, of a starch gel at a particle volume fraction of 1 is defined as rigidity), forming stronger gels than O. tuberosa and A. xanthorriza. Storage of the three starch gels at 4 8C showed that A. xanthorriza formed gels which were stable in G0 and phase angle for three days of storage. C. edulis and O. tuberosa gels kept at the same refrigeration conditions showed a high increase in G0 during the first day of storage. A decrease in pH from 6.5 to 4.0 produced a loss of structure in the three starch gels, as was showed by the reduction of G0. Storage at freezing temperature (220 8C) produced higher changes in G0 than refrigeration conditions. There was a rapid formation of an elastic structure in C. edulis and O. tuberosa starch gels on the first day of storage in both refrigeration and freezing conditions.

• Author: S Santacruz; J Ruales; Ann-Charlotte Eliasson
• Department/s: Department of Food Technology, Engineering and Nutrition
• Publishing year: 2003
• Language: English
• Pages: 85-92
• Publication/Series: Carbohydrate Polymers
• Volume: 51
• Issue: 1
• Links: http://dx.doi.org/10.1016/S0144-8617(02)00140-6
• Document type: Journal article
• Publisher: Elsevier
• Topic: Food Engineering
• Keywords: Retrogradation; Oxalis tuberosa; Arracacha xanthorriza; Canna edulis; Freezing storage; Refrigeration storage
• Status: Published
• ISBN/ISSN/Other: ISSN: 0144-8617