Development of time-pH indicator nanofibers from natural pigments: An emerging processing technology to monitor the quality of foods. (May 2021)

• Record Type: Journal Article
• Authors: Terra, Ana Luiza Machado; Moreira, Juliana Botelho; Costa, Jorge Alberto Vieira; Morais, Michele Greque de
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 142(2021)
• Publication Date: 2021-05
• Subjects: Colorimetric indicator -- Curcumin -- Electrospinning -- Phycocyanin -- Quercetin; Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2021.111020
• Languages: English
• ISSNs: 0023-6438

Abstract

Abstract: Colorimetric indicators produced from nanofibers have a high contact surface area, allowing better interaction of the indicator with the external environment. In this context, this study aimed to develop time-pH indicator nanofibers with natural pigments for use as an emerging technology in the control of food quality. The polymeric solutions were prepared with 13% (w v −1 ) polycaprolactone (PCL) and 6% (w v −1 ) poly (ethylene oxide) (PEO). The natural dyes added to the polymeric solution were curcumin and quercetin (2%, w v −1 ) with the addition of 0.5 or 1% (w v −1 ) of phycocyanin. Solutions with curcumin, quercetin, and phycocyanin only (2% w v −1 ) were also studied. The color change monitoring was performed for 24 h, followed up every 1 h, using buffer solutions (pH 2 to 7). The condition with 2% (w v −1 ) phycocyanin showed a color variation (ΔE ≥ 5) noticeable to the human eye in the pH range 3–6 in 5 h of analysis. Thus, the indicator developed with PCL/PEO nanofibers containing 2% (w v −1 ) of phycocyanin is a promising alternative in monitoring the quality of perishable foods, as it can visually estimate changes in pH over time. Graphical abstract: Image 1 Highlights: The smallest diameter (550 nm) was found by PCL/PEO nanofiber with 2% curcumin. PCL/PEO nanofiber developed with 2% phycocyanin showed the highest amplitude of ΔE. Nanofibers with 2% phycocyanin presented an increasing colorimetric profile in 20h. The hydrophobicity of the indicator influenced the best result obtained from ΔE.