INTELIGENT INDIKATOR pH BERBASIS ANTOSIANIN LIMBAH KULIT BAWANG MERAH UNTUK DETEKSI KESEGARAN UDANG - Amsikan, Apriani; Adu, Risna Erni Yati; D. Gelyaman, Gebhardus (Graduate Program of Applied Chemistry, Udayana University, Bali-INDONESIA, 2023)
ABSTRAK: Tingkat kesegaran udang dalam kemasan sulit terdeteksi oleh konsumen tanpa membuka kemasan, sehingga dibutuhkan pengembangan indicator visual berbasis perubahan pH. Penelitian ini bertujuan untuk menghasilkan indicator visual yang dapat mendeteksi perubahan pH akibat perubahan kesegaran udang. Indikator pH difabrikasi dari polimer selulosa dan ekstrak kulit bawang merah melalui metode solution casting. Karakteristik film ditentukan menggunakan FTIR dan SEM. Respon film diuji terhadap larutan buffer pH yang berbeda dan sampel udang selama masa penyimpanan. Hasil karakterisasi film menunjukkan adanya serapan gugus spesifik selulosa dan antosianin yaitu -OH, CH, C-O-C, C=C. Analis SEM menunjukkan bahwa film dengan ekstrak antosianin memiliki permukaan yang homogen. Film menghasilkan perubahan warna dari orange kemerahan menjadi merah kecoklatan seiring dengan perubahan pH sampel dari 7,93 sampai 10,26. Film selulosa antosianin berpotensi digunakan sebagai indikator untuk mendeteksi kesegaran udang. ABSTRACT: It is a difficult thing for consumers to detect the freshness level of packaged shrimp without opening the package, so a visual indicator based on pH changes is needed to develop. This study aims to produce a visual indicator that can detect pH changes due to changes of shrimp freshness. The pH indicator was fabricated from cellulose polymer and shallot skin extract through solution casting method. Film characteristics were determined by using FTIR and SEM. Film response was tested against different pH buffer solutions and shrimp samples during storage. The results of FTIR characterization showed specific absorption for cellulose and anthocyanin groups, namely -OH, CH, C-O-C, C=C. SEM analysis showed that the films with anthocyanin extracts had a smooth and compact surface. The film gave a color change from reddish orange to brownish red along with pH changes of sample from 7.93 to 10.26. Anthocyanin cellulose film has the potential to be used as a real-time indicator to detect shrimp freshness