Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Articles Article Faculty Publications -Articles Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource A Smartphone Coupled Freshness Indicator Prepared by Rub-coating of Hibiscus Flowers on Paper substrates for Visual Monitoring of the Spoilage of Milk Subject The topic of the resource colorimetric interface; food spoilage monitoring; halochromic interface; milk quality; smartphone-based sensor Description An account of the resource This study developed an inexpensive and easy-to-use milk freshness indicator (H-Paper) by rub-coating hibiscus flowers onto paper. As per the best of our knowledge, this is the first example of a food quality indicator prepared by direct hand-rubbing of a natural halochromic material onto paper substrates. Unlike the previously reported colorimetric indicators from natural sources, our indicator does not require the extraction of anthocyanins from the natural product. The H-Paper undergoes a quantifiable color change from green to purple to pink corresponding to fresh, spoiling, and spoiled milk samples. Digital photographs of H-Paper treated with milk samples were acquired using a smartphone, and RGB indices were analyzed using a free application. The red chromatic shift was used as a parameter to quantify color change of H-Paper to follow the spoilage of milk. Anthocyanins present in the hibiscus flowers are responsible for this colorimetric response. This work demonstrates a proof-of-concept for directly rub-coating halochromic materials onto a substrate to fabricate food freshness indicators. The H-Paper indicator has advantages of naked-eye analysis, consumer-friendliness, and instrument-free operation. This requires neither any laboratory accessories nor the expertise of a trained analyst for its preparation and operation, which is appropriate for use in resource-limited settings. 2022 Wiley-VCH GmbH. Creator An entity primarily responsible for making the resource Chaithra K.P.; Vinod T.P. Source A related resource from which the described resource is derived ChemistrySelect, Vol-7, No. 41 Publisher An entity responsible for making the resource available John Wiley and Sons Inc Date A point or period of time associated with an event in the lifecycle of the resource 2022-01-01 Identifier An unambiguous reference to the resource within a given context <a href="https://doi.org/10.1002/slct.202201839" target="_blank" rel="noreferrer noopener">https://doi.org/10.1002/slct.202201839</a> <br /><br /><a href="https://www.scopus.com/inward/record.uri?eid=2-s2.0-85141742065&amp;doi=10.1002%2Fslct.202201839&amp;partnerID=40&amp;md5=1eb54f4508f574d1b85f6c83e77ec4fa" target="_blank" rel="noreferrer noopener">https://www.scopus.com/inward/record.uri?eid=2-s2.0-85141742065&amp;doi=10.1002%2fslct.202201839&amp;partnerID=40&amp;md5=1eb54f4508f574d1b85f6c83e77ec4fa</a> Rights Information about rights held in and over the resource Restricted Access Relation A related resource ISSN: 23656549 Format The file format, physical medium, or dimensions of the resource Online Language A language of the resource English Type The nature or genre of the resource Article Coverage The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant Chaithra K.P., Department of Chemistry, CHRIST (Deemed to be University), Hosur Road, Bengaluru, 560029, India; Vinod T.P., Department of Chemistry, CHRIST (Deemed to be University), Hosur Road, Bengaluru, 560029, India