Evaluation of hot and cold extraction of bioactive compounds in teas. (20th June 2015)

• Record Type: Journal Article
• Authors: de Carvalho Rodrigues, Vanessa; da Silva, Marcos V.; dos Santos, Adriele R.; Zielinski, Acácio A. F.; Haminiuk, Charles W. I.
• Is Part Of: International journal of food science & technology. Volume 50:Number 9(2015:Sep.)
• Page Start: 2038
• Page End: 2045
• Publication Date: 2015-06-20
• Subjects: Food industry and trade -- Periodicals; 664
• DOI: 10.1111/ijfs.12858
• Languages: English
• ISSNs: 0950-5423

Abstract

<abstract abstract-type="main" id="ijfs12858-abs-0001"> <title>Summary</title> <p>This study evaluated the bioactive compounds of different types of tea by comparing hot and cold infusions. A multivariate data analysis was carried out, where the principal components analysis (PCA) and hierarchical cluster analysis (HCA) were used. Phenolic compounds varied between 267.27–2896.00 mg GAE L⁻¹ and 215.10–7351.33 mg GAE L⁻¹ for hot (80 °C) and cold extraction (20–25 °C), respectively. In the case of their antioxidant activity, results with DPPH were 43.10‐73.67% for hot extraction and 46.80‐77.13% for cold extraction. The average values for the ABTS˙⁺ method ranged between 2535.43 and 33 300.17 μmol TE L⁻¹ and between 1110.34 and 38 300.67 μmol TE L⁻¹, respectively, for hot and cold extraction. Different compounds were identified by liquid chromatography in the samples evaluated, where caffeine presented the higher concentrations in the teas. Samples of green and black tea (hot extraction) and white tea (cold extraction) showed bacteriostatic activity for <italic>S. aureus</italic> and <italic>E. coli</italic>. No extract had any bactericide activity. The current study revealed that cold infusion was more efficient in the extraction of bioactive compounds.</p> </abstract>