Antioxidant and rheological properties of guava jam with added concentrated grape juice

作者：Correa Rubia C G; Haminiuk Charles W I^*; Sora Gisele T S; Bergamasco Rosangela; Vieira Angelica M S

来源：Journal of the Science of Food and Agriculture, 2014, 94(1): 146-152.

DOI：10.1002/jsfa.6233

• food enrichment
• functional food
• fruits
• phenolics
• antioxidant activity
• rheological behavior study

BACKGROUNDGuava jam enriched by the addition of concentrated grape juice in the proportion of 30% (w/w) (ENR) was studied for its antioxidant potential and rheological behavior. Total phenolics content, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH center dot) scavenging activity and -carotene-linoleic acid coupled oxidation assays were used to evaluate the antioxidant properties of the samples during storage for 90 days at room temperature (25 degrees C).
RESULTSThe ENR showed a total phenolic content of 11.09 g GAE kg(-1) of jam at production, more than two-fold the phenolic content presented by the standard formulation (STA). For the ENR formulation the antioxidant capacity increased in almost 20% (P 0.05) with time on the -carotene assay and decreased with time on the DPPH assay. The enriched guava jam exhibited a non-Newtonian shear-thinning behavior at temperatures ranging from 25 to 55 degrees C, and, moreover, presented higher stability than the standard formulation when exposed to temperature variation.
CONCLUSIONENR constitutes an original food product with a notable antioxidant potential, even greater than the potential presented by the standard guava jam, worldwide appreciated delicacy.

• 出版日期2014-1-15