INTERAKSI pH DAN EKSTRAK GAMBIR PADA PEMBUATAN EDIBLE FILM ANTI BAKTERI (Interaction of pH and Unrica gambir Roxb Extract in the Production of Antibacterial Edible Film)

Abstract

The objective of the study was to investigate the effects of pH value and Uncaria gambir Roxb extract addition on physical, chemical and antibacterial properties of edible film. Two factors were evaluated, namely pH value (5, 7, 9) and Uncaria gambir Roxb extract addition (2%, 4%, 6% w/v). The research used Completely Randomized Design Factorial and was conducted in a triplicate. The observed parameters included chemical (water activity), physical (thickness, percent of elongation, vapor transmission rate) and antibacterial properties. The results showed that the pH values had significant effects on water activity, percent of elongation, vapor transmission rate and solubility), while Uncaria gambir Roxb extract addition affected all parameters significantly, except antibacterial property. Interaction of the factors had significant effects on water activity, vapor transmission rate, and solubility. However, no antibacterial activity was observed in edible film. Furthermore, the edible film met Japanese Industrial (JIS) standard based on thickness 0.203 to 0.244 mm, vapor transmission rate 8.25 to 9.59 gm-2. day-1 and the percent of elongation 48.6 to 110%. Keywords: Antibacterial activity, edible film, Uncaria gambir Roxb, pH ABSTRAK Tujuan penelitian ini adalah untuk mengetahui pengaruh pH dan penambahan ekstrak gambir terhadap sifat fisik, kimia, dan antibakteri edible film. Faktor perlakuan ada dua yaitu pH (5,7, dan 9) dan penambahan ekstrak gambir (2,4, dan 6%b/v). Rancangan penelitian yang digunakan adalah rancangan acak lengkap faktorial dengan tiga kali ulangan. Parameter yang diamati adalah aktivitas air, ketebalan, warna, persen pemanjangan (elongation), laju transmisi uap air, kuat tekan, dan aktivitas antibakteri. Hasil penelitian menunjukkan bahwa pH berpengaruh nyata terhadap aktivitas air, persen pemanjangan, laju transmisi uap air, dan kelarutan, sedangkan penambahan ekstrak gambir berpengaruh nyata terhadap semua parameter, kecuali aktivitas antibakteri. Perlakuan interaksi berpengaruh nyata terhadap aktivitas air, laju transmisi uap air, dan kelarutan, namun tidak terdapat aktivitas antibakteri. Selanjutnya, edible film yang dihasilkan memenuhi standar JIS 1975 yaitu ketebalan 0,203 hingga 0,244 mm, laju transmisi uap air 8,25 hingga 9,59 g.m, dan persen pemanjangan 48,6 hingga 110%. Kata kunci: Aktivitas antibakteri, edible film, ekstrak gambir, pH