Preparation and characterization of indicator films from carboxymethyl-cellulose/starch and purple sweet potato (Ipomoea batatas (L.) lam) anthocyanins for monitoring fish freshness

• Published in: International journal of biological macromolecules Vol. 143; pp. 359 - 372
• Main Authors: Jiang, Guangyang, Hou, Xiaoyan, Zeng, Xuedan, Zhang, Can, Wu, Hejun, Shen, Guanghui, Li, Shanshan, Luo, Qingying, Li, Meiliang, Liu, Xingyan, Chen, Anjun, Wang, Zhangying, Zhang, Zhiqing
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.01.2020
• Subjects: ammonia; Anthocyanins; Carboxymethyl-cellulose; carboxymethylcellulose; color; differential scanning calorimetry; fish; Fish freshness; food packaging; Fourier transform infrared spectroscopy; freshness; Indicator film; Ipomoea batatas; melting point; monitoring; Purple sweet potato; scanning electron microscopy; Starch; storage temperature; sweet potatoes; tensile strength; total volatile basic nitrogen; water content; X-ray diffraction; Anthocyanins; Purple sweet potato; Indicator film; Starch; Fish freshness; Carboxymethyl-cellulose
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2019.12.024

A novel indicator film from carboxymethyl-cellulose (CMC)/starch (S) and purple sweet potato anthocyanins (PSPA) was prepared and characterized. The Fourier transform infrared spectroscopic (FT-IR) analysis indicated that new interaction were generated between the components of the film, and the scanning electron microscopic (SEM) and X-ray diffraction spectra (XRD) showed that PSPA was well dispersed in CMC and starch-based film. The results from differential scanning calorimetric (DSC) analysis revealed that the novel film had increased melting temperature. The addition of PSPA into the film resulted in the increase of tensile strength but the decrease of elongation at break and moisture content. The analysis of color change demonstrated that the film color was changed from red to blue and green when exposed to different pH or ammonia. In their application trial, the SCA film was used as labels to monitor the freshness of fish stored at 20 °C, and the results showed that the color of the film was changed from red to blue when the fish became spoiled. The observation was consistent with the TVB-N value, which was higher than the set limit (20 mg/100 g). Hence, the novel indicator film could be used as intelligent food packaging to monitor fish freshness. [Display omitted] •Carboxymethyl-cellulose/starch/ anthocyanin indicator films were developed•The compatibility between CMC and starch was improved by anthocyanin•The indicator films were sensitive to NH3 and pH changes•The indicator films can be used to monitor the real-time freshness of fish