Study of the antioxidant properties of extracts obtained from nopal cactus (Opuntia ficus-indica) cladodes after convective drying

J Sci Food Agric. 2011 Apr;91(6):1001-5. doi: 10.1002/jsfa.4271. Epub 2011 Feb 2.

Abstract

Background: The process of convective drying was evaluated in terms of the bioactive compounds contained in nopal samples before and after dehydration. Total polyphenol, flavonoid, flavonol, carotene and ascorbic acid contents were determined in undehydrated and dehydrated samples. Two drying temperatures (45 and 65 °C) and two air flow rates (3 and 5 m s(-1) ) were evaluated. The rheology of samples under the best drying conditions was also studied, since it provides important information regarding processing (mixing, flow processing) as well as the sensory attributes (texture) of rehydrated samples.

Results: Non-Newtonian shear-thinning behaviour was observed for samples dried at 45 °C, while samples dried at 65 °C showed shear-thickening behaviour, possibly caused by thermal chain scission of high-molecular-weight components.

Conclusion: The best conditions for bioactive compound preservation were a drying temperature of 45 °C and an air flow rate of 3 m s(-1) , resulting in 40.97 g phenols, 23.41 g flavonoids, 0.543 g β-carotene and 0.2815 g ascorbic acid kg(-1) sample as shown in table 3.

Publication types

  • Comparative Study

MeSH terms

  • Antioxidants / analysis*
  • Ascorbic Acid / analysis
  • Chemical Phenomena
  • Flavonoids / analysis
  • Food Handling / methods*
  • Functional Food / analysis
  • Hot Temperature
  • Mexico
  • Opuntia / chemistry*
  • Phenols / analysis
  • Plant Components, Aerial / chemistry*
  • Plant Extracts / chemistry*
  • Polyphenols
  • Rheology
  • Viscosity
  • Water / analysis
  • beta Carotene / analysis

Substances

  • Antioxidants
  • Flavonoids
  • Phenols
  • Plant Extracts
  • Polyphenols
  • beta Carotene
  • Water
  • Ascorbic Acid