EDIBLE FILMS AND COATINGS BASED ON GELATIN-HYDROXYAPATITE-LINOLEIC ACID AND THEIR APPLICATION ON GRAPE SURFACE FOR SHELF-LIFE EXTENSION

PETER ANTHONIO N, Prof. Dr. Yudi Pranoto, STP. MP.

2020 | Skripsi | S1 TEKNOLOGI PANGAN DAN HASIL PERTANIAN

Edible film berbahan dasar gelatin dipersiapkan dari gelatin ikan dengan penambahan langsung asam linoleat teroksidasi (OLA) dengan perbedaan konsentasi (10-30%, w/w gelatin) dan bubuk hydroxyapatite (HAp) yang diolah dari waste tulang ikan salmon dengan berbagai variasi (1-3%, w/w gelatin). Sampel dikarakterisasi lewat perbandingannya dengan film kontrol (tanpa penambahan OLA dan HAp). Film dengan penambahan langsung OLA mempunyai nilai tensile strength (TS), elastic modulus (EM) lebih rendah tetapi elongation, water vapor permeability (WVP), dan yellowness (b*-value) yang lebih tinggi dibandingkan kontrol (p < 0.05). Sementara, penambahan bubuk HAp menurunkan nilai elongation tetapi TS, EM, WVP, dan whiteness (L*-value) lebih tinggi daripada film kontrol (p < 0.05). Penambahan langsung OLA membantu penyebaran merata dari partikel HAp dan partikel HAp dapat mengganggu aglomerasi dari OLA. Baik penambahan OLA maupun bubuk HAp dapat meningkatkan viskositas larutan film dan ketebalan film. Perpanjangan umur simpan dari anggur diuji. Anggur di-dip-coated hingga 1-3 lapis dengan larutan kontrol (hanya gelatin) dan gelatin dengan 20%OLA 5%HAp dibandingkan dengan sampel tanpa coating. Pengurangan berat dan penampakan dari sampel dimonitor dalam kondisi normal dan penyimpanan dingin selama 14 hari. Anggur yang dilapisi dengan larutan gelatin+20% OLA 5% HAp memiliki penampakan yang lebih baik daripada kontrol dan tanpa coating. Namun, coating dengan beberapa lapis larutan kontrol lebih menghambat penurunan bobot daripada coating dengan larutan gelatin+20% OLA 5%HAp dan sampel tanpa coating.

Edible gelatin-based films were prepared from fish gelatin with direct addition of oxidized linoleic acid (OLA) at various levels (10-30%, w/w, of gelatin) and hydroxyapatite (HAp) powder derived from salmon bone waste at various levels (1-3%, w/w. of gelatin). Samples were characterized, in comparison to control film (without the addition of OLA and HAp). Films with direct addition of OLA had lower tensile strength (TS), elastic modulus (EM) but higher elongation, water vapor permeability (WVP), and yellowness (b*-value), as compared to the control film (p < 0.05). Meanwhile, the addition of HAp powder had lower elongation but higher TS, EM, WVP, and whiteness (L*-value) of the films compared to the control (p < 0.05). The direct addition of OLA help to spread HAp particles evenly and HAp particles would disturb the agglomeration of OLA droplets. Both additions of OLA and HAp powder increased viscosity of film casting solution and hence the casted film thickness. Shelf-life extension of seedless grapes were investigated. The grapes were dip-coated by 1-3 layers of the control (gelatin only) and the gelatin with 20% OLA 5% HAp solutions in comparison to the uncoated samples. Weight loss and appearance of the samples were monitored under regular atmosphere and refrigerated storages for 14 days. Grapes coated with gelatin+20% OLA 5% HAp solution had better appearance than control and uncoated grapes. However, multiple coating of the control solution resulted in better weight loss inhibition than those coated with gelatin+20% OLA 5% HAp solution and uncoated grapes, respectively.

Kata Kunci : Edible film, Gelatin, Hydroxyapatite, Oxidized Linoleic Acid