KINETIKA KERUSAKAN BAKSO BERLAPISKAN EDIBLE AKTIF BERBASIS PATI KIMPUL (Xanthosoma sagittifolium) SELAMA PENYIMPANAN

WARKOYO, IR, MP, Prof. Dr. Ir. Budi Rahardjo, MSAE.,; Prof. Dr. Ir. Djagal Wiseso Marseno, M.Agr.; Dr. Joko Nugroho W.K., STP, M.Eng.,

2015 | Disertasi | S3 Ilmu Teknik Pertanian

mikrobia dari lingkungan tidak dapat bersinggungan langsung dengan makanan. Apabila mikrobia tersebut dapat merusak pelapis edible, mencapai permukaan pangan dan berkembang biak, maka akan menjadikan makanan tidak bisa dikonsumsi. Masalahnya adalah berapa lama mikrobia tersebut mencapai permukaan makanan. Solusi yang diharapkan adalah mikrobia mencapai permukaan makanan dalam waktu yang lama. Tujuan penelitian ini yang pertama adalah untuk mendapatkan sifat fisikmekanik edible film aktif berbasis pati umbi kimpul akibat keragaman konsentrasi pati dan kalium sorbat. Kedua adalah untuk mendapatkan model perubahan populasi mikrobia, dan sifat kimia-fisik bakso berpelapis edible aktif akibat keragaman konsentrasi kalium sorbat, ketebalan pelapis, dan suhu penyimpanan. Desain percobaan disusun dalam 4 tahap, yaitu pembuatan dan pengujian sifat fisik edible film berbasis pati kimpul, yang dilanjutkan dengan aplikasi pelapis edible aktif pada bakso dengan keragaman konsentrasi kalium sorbat, ketebalan pelapis, dan suhu penyimpanan. Parameter pengamatan meliputi sifat fisik-mekanik edible film dan perubahan populasi mikrobia, kadar protein, TVB-N, tingkat kekerasan, dan susut bobot bakso berpelapis edible aktif. Hasil penelitian menunjukkan bahwa penambahan pati umbi kimpul menyebabkan kuat tarik, ketebalan, laju transmisi uap air, dan kehalusan permukaan edible film meningkat, tetapi kelarutannya dalam air menurun. Penambahan kalium sorbat menyebabkan laju pertumbuhan mikrobia, laju pertambahan TVB-N, dan laju pengerasan bakso menurun. Penambahan ketebalan pelapis menyebabkan laju pertumbuhan mikrobia, dan pertambahan TVB-N meningkat. Peningkatan suhu penyimpanan menyebabkan laju pertumbuhan mikrobia, penurunan kadar protein, pertambahan TVB-N, dan penyusutan bobot bakso meningkat. Model matematik yang dikembangkan untuk pertumbuhan mikrobia, penurunan kadar protein, peningkatan kadar TVB-N, dan peningkatan susut bobot merupakan fungsi dari konsentrasi kalium sorbat, ketebalan pelapis, dan suhu penyimpanan. Model pertumbuhan mikrobia mempunyai kepekaan terhadap perubahan suhu penyimpanan sebesar 83%, dan model pertambahan TVB-N mempunyai kepekaan terhadap perubahan kadar kalium sorbat dalam pelapis edible aktif sebesar 65,5%. Bakso berpelapis edible aktif berbasis pati umbi kimpul dengan kalium sorbat 0,6%, ketebalan pelapis 0,43 mm, dan suhu penyimpanan 27 oC menghasilkan umur simpan 4 hari, sementara bakso tanpa pelapis (kontrol) hanya bertahan 1 hari. ii Dengan demikian, pelapis edible aktif tersebut dapat menghambat kerusakan bakso sebesar 75 %.

The presence of active edible coating on food surfaces caused microbes from the environment unable to interact directly with the food. If these microbes tear down the edible coatings, reaching food surfaces and growing, it will make the food non-consumable. The problem is that how long the microbes can reach food surfaces. The expected solution is that it takes a long time for the microbes to reach food surfaces. The first aim of this study was to obtain physical-mechanical characteristics of pure starch-based active edible film due to the variety of starch concentration and potassium sorbate. The second was to obtain a change of model of microbes population, and chemical-physical properties of active edible coated meatballs due to the various the potassium sorbat concentration, coating thickness, and the storage temperature. The design of experiments were arranged in four stages, namely the making and testing of the physical-mechanical characteristics of purse starch-based edible films, which was followed by the application of active edible coatings on the various potassium sorbat concentration, coating thickness, and the storage temperature. Observation parameters include the physical-mechanical characteristics of edible film and the changes of microbes population, protein content, TVB-N content, hardness, and water losses of active edible coated meatballs. The results showed that the addition of purse starch causes tensile strength, thickness, water vapor transmission rate, and edible film surface smoothness increase, but its the water solubility decrease. The addition of potassium sorbate increases the rate of microbial growth, the rate of TVB-N, and decreases the rate meatballs hardness rate. The increase in coating thickness causes the rate of microbial growth and the addition of TVB-N to increase. The increase in the storage temperature causes the rate of microbial growth, protein content, increase of TVB-N and water losses were increased. Mathematical models developed for microbial growth, a decrease in protein content, an increase in TVB-N, and water losses are a function of the concentration of potassium sorbate, coating thickness, and the storage temperature. Microbial growth models have the sensitivity in storage temperature changes by 83%, and models of TVB-N addition have sensitivity the changes of the levels of potassium sorbate concentrations by 65.5%. Purse starch-based active edible coated meatballs with 0.6% potassium sorbate, a coating thickness of 0.43 mm, and the storage temperature of 27 oC produce a shelf life of 4 days, while the meatballs without coating (control) only last one day. Thus, the active edible coatings can inhibit meatballs damage as many as 75%.

Kata Kunci : kinetika, kerusakan bakso, pelapis edible aktif, pati kimpul, kalium sorbat