Next Article in Journal
Membrane-Based Clarification and Fractionation of Red Wine Lees Aqueous Extracts
Previous Article in Journal
Hydrogel Tissue Expanders for Stomatology. Part II. Poly(styrene-maleic anhydride) Hydrogels
Previous Article in Special Issue
The Thermal and Mechanical Properties of Poly(ethylene-co-vinyl acetate) Random Copolymers (PEVA) and its Covalently Crosslinked Analogues (cPEVA)
Article Menu

Export Article

Version is current.

Open AccessArticle

Synthesis of Intelligent pH Indicative Films from Chitosan/Poly(vinyl alcohol)/Anthocyanin Extracted from Red Cabbage

1
Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
2
Department of Chemical Technology, Ho Chi Minh City University of Food Industry, Ho Chi Minh City 70000, Vietnam
*
Author to whom correspondence should be addressed.
Polymers 2019, 11(7), 1088; https://doi.org/10.3390/polym11071088
Received: 14 May 2019 / Revised: 22 June 2019 / Accepted: 24 June 2019 / Published: 26 June 2019
(This article belongs to the Special Issue Polymer Structure and Properties)
  |  
PDF [5852 KB, uploaded 27 June 2019]
  |  

Abstract

In this study, pH indicative films were successfully synthesized from hydrogels made by blending 1% poly(vinyl alcohol) (PVA) and 1% chitosan (CS) with anthocyanin (ATH) and sodium tripolyphosphate (STPP). Particularly, ATH extracted from red cabbage was used as the pH indicator, while STPP was utilized as the cross-linking agent to provide better mechanical properties of the cast films. FT-IR spectra confirmed the existence of the ATH in the cast films. Moreover, the tensile strength, the elongation-at-break, and the swelling indices of the cast films were measured. In general, these properties of pH indicative films were profoundly influenced by the compositions of PVA/CS and the STPP dosage applied in the hydrogels. For example, the tensile strength could change from 43.27 MPa on a film cast from pure PVA hydrogel to 29.89 MPa, if 35% of the PVA hydrogel was substituted with CS. The cast films were applied as a food wrap that could be used to monitor visually the quality of the enwrapped food via the color change of the film upon the variation in pH values of the enwrapped food. In practice, a sequential change in color was successfully observed on the pH indicative films partially enwrapping the pork belly, indicating the spoilage of the meat. View Full-Text
Keywords: poly(vinyl alcohol); chitosan; anthocyanin; pH indicative film; food wrap poly(vinyl alcohol); chitosan; anthocyanin; pH indicative film; food wrap
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Vo, T.-V.; Dang, T.-H.; Chen, B.-H. Synthesis of Intelligent pH Indicative Films from Chitosan/Poly(vinyl alcohol)/Anthocyanin Extracted from Red Cabbage. Polymers 2019, 11, 1088.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top