{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T16:15:21Z","timestamp":1771258521105,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,11,5]],"date-time":"2019-11-05T00:00:00Z","timestamp":1572912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007702","name":"Institut Penyelidikan dan Kemajuan Pertanian Malaysia","doi-asserted-by":"publisher","award":["GP-005179-2016"],"award-info":[{"award-number":["GP-005179-2016"]}],"id":[{"id":"10.13039\/501100007702","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A developed colorimetric pH sensor film based on edible materials for real-time monitoring of food freshness is described. The mixed natural dyes from edible plants Clitoria sp and Brassica sp were extracted and incorporated into \u03b9-carrageenan film as a colorimetric pH sensor film for monitoring food spoilage and its freshness. The color changes of the developed colorimetric sensor film were measured with chromametry and UV-vis spectroscopy, respectively. Experimental results show that colorimetric pH sensor film demonstrated statistically significant differences (p &lt; 0.05) between CIE-L*a*b* coordinates color system indicated that the developed colorimetric sensor film was able to give a gradual change in color over a wide pH range. The color of the colorimetric sensor film also changes discretely and linearly with factors that contribute to food spoilage using shrimp and durian samples. Moreover, the developed colorimetric pH sensor film has the potential to be used as a safe, non-destructive testing and also a flexibly visual method for direct assessment of food freshness indicator during storage.<\/jats:p>","DOI":"10.3390\/s19214813","type":"journal-article","created":{"date-parts":[[2019,11,7]],"date-time":"2019-11-07T02:48:31Z","timestamp":1573094911000},"page":"4813","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":64,"title":["A Colorimetric pH Sensor Based on Clitoria sp and Brassica sp for Monitoring of Food Spoilage Using Chromametry"],"prefix":"10.3390","volume":"19","author":[{"given":"Noor Azizah","family":"Ahmad","sequence":"first","affiliation":[{"name":"Center for Advanced Materials and Renewable Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia"},{"name":"Malaysian Agricultural Research Development Institute, Serdang 43400, Selangor, Malaysia"}]},{"given":"Lee","family":"Yook Heng","sequence":"additional","affiliation":[{"name":"Center for Advanced Materials and Renewable Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia"}]},{"given":"Faridah","family":"Salam","sequence":"additional","affiliation":[{"name":"Malaysian Agricultural Research Development Institute, Serdang 43400, Selangor, Malaysia"}]},{"given":"Mohd Hazani","family":"Mat Zaid","sequence":"additional","affiliation":[{"name":"Center for Advanced Materials and Renewable Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia"}]},{"given":"Sharina","family":"Abu Hanifah","sequence":"additional","affiliation":[{"name":"Center for Advanced Materials and Renewable Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,5]]},"reference":[{"key":"ref_1","first-page":"47","article-title":"Food Spoilage: Microorganisms and their prevention","volume":"5","author":"Rawat","year":"2015","journal-title":"Asian J. 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