title: Intelligent pH indicator film composed of agar/potato starch and anthocyanin extracts from purple sweet potato.
abstract: A new colorimetric pH indicator film was developed using agar, potato starch, and natural dyes extracted from purple sweet potato, Ipomoea batatas. Both agar and potato starch are solid matrices used to immobilize natural dyes, anthocyanins. The ultraviolet-visible (UV-vis) spectrum of anthocyanin extract solutions and agar/potato starch films with anthocyanins showed color variations to different pH values (pH 2.0-10.0). Fourier transform infrared (FT-IR) and UV-vis region spectra showed compatibility between agar, starch, and anthocyanin extracts. Color variations of pH indicator films were measured by a colorimeter after immersion in different pH buffers. An application test was conducted for potential use as a meat spoilage sensor. The pH indicator films showed pH changes and spoilage point of pork samples, changing from red to green. Therefore, the developed pH indicator films could be used as a diagnostic tool for the detection of food spoilage.
authors.affiliation: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea. Electronic address: haunlzy@naver.com.
authors.forename: Inyoung
authors.initials: I
authors.lastname: Choi
authors.affiliation: Korea Institute of Industrial Technology, Cheonan-si, Chungcheongnam-do 31056, Republic of Korea. Electronic address: jaylee@kitech.re.kr.
authors.forename: Jun Young
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Research Laboratory of Sciences Applied to Food, INRS-Institut Armand Frappier, Canadian Irradiation Centre, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada. Electronic address: monique.lacroix@iaf.inrs.ca.
authors.forename: Monique
authors.initials: M
authors.lastname: Lacroix
authors.affiliation: Department of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea. Electronic address: jjhan@korea.ac.kr.
authors.forename: Jaejoon
authors.initials: J
authors.lastname: Han
mesh_terms: D000362:Agar / Q000737:chemistry*; D000818:Animals; D000872:Anthocyanins / Q000737:chemistry* / Q000302:isolation & purification; D018857:Food Packaging / Q000379:methods / Q000592:standards; D006863:Hydrogen-Ion Concentration; D027723:Ipomoea batatas; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D000069466:Red Meat / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013213:Starch / Q000737:chemistry*; D013552:Swine
chemical_list: D000872:Anthocyanins; D010936:Plant Extracts; D000362:Agar; D013213:Starch
keywords: Agar; Anthocyanin; Intelligent packaging; Potato starch; Purple sweet potato; pH indicator