PENGARUH EKSTRAK JAHE (Zingiber officinale) TERHADAP PERTUMBUHAN MISELIA DAN VIABIL ITAS SPORA JAMUR PERUSAK DODOL

EKO ADI NUGROHO, Prof. Dr. Ir. Sardjono, M.S.

2013 | Skripsi | TEKNOLOGI PANGAN & HASIL PERTANIAN

Dodol termasuk Intermediate Moisture Food (IMF) dengan Aw berkisar antara 0,7 – 0,79. Selama penyimpanan dodol masih rentan terhadap kerusakan terutama yang disebabkan oleh jamur xerofilik. Jahe (Zingiber officinale) merupakan salah satu jenis rempah-rempah yang terbukti memiliki aktivitas antijamur dan sering ditambahkan pada produk pangan. Ekstrak jahe (Zingiber officinale) dapat dimanfaat pada dodol sebagai bahan pengawet alami sehingga dapat mengurangi penggunaan bahan pengawet buatan. Berdasarkan permasalahan tersebut maka dilakukan penelitian untuk mengetahui pengaruh ekstrak jahe (Zingiber officinale) terhadap pertumbuhan miselia dan viabilitas spora jamur perusak dodol. Ekstrak jahe yang digunakan pada penelitian ini diperoleh dengan cara memblander rimpang jahe dengan aquades steril (1:1 b/v). Ekstrak jahe hasil pemblanderan selanjutnya disaring dengan kain saring, disentrifuge (3000 rpm, 10 menit), dan disaring kembali dengan kertas Whatman No 1 steril rangkap dua. Isolasi dilakukan dengan metode direct platting pada media Czapek Yeast Extract Agar dengan 20% Sukrosa (CY20S). Uji pertumbuhan miselia dilakukan dengan menginokulasikan satu titik suspensi spora ditengah media CY20S yang ditambahkan ekstrak jahe dan diukur diameter koloninya selama inkubasi. Sedangkan uji viabilitas spora dilakukan dengan menginokulasikan suspensi spora secara spread plate pada media Czapek Yeast Extract Agar (CYA) yang ditambahkan ekstrak jahe dan dihitung pertambahan jumlah koloni selama inkubasi. Inkubasi dilakukan selama 5 hari pada suhu 30oC. Konsentrasi ekstrak jahe pada media uji adalah 0%, 2%, 4%, 6%, 8%, dan 10%. Diperoleh 6 isolat jamur perusak dodol, 3 isolat genera Aspergilus yaitu J1B-A, J1MA-B, J1B-C dan 3 isolat genera Monascus yaitu J2MA-D, J4MA-E, J4B-F. Hasil pengujian pertumbuhan miselia menunjukkan bahwa semakin tinggi konsentrasi ekstrak jahe pada media maka akan semakin menghambat pertumbuhan jamur. Namun, penambahan ekstrak jahe hingga konsentrasi 10% tidak dapat menghentikan pertumbuhan seluruh isolat jamur. Hasil uji viabilitas spora menunjukkan bahwa ekstrak jahe dapat menunda perkecambahan dan menurunkan viabilitas spora jamur perusak dodol. Ekstrak jahe sebanyak 8-10% dapat menunda perkecambahan jamur Aspergillus isolat J1B-A selama 2 hari dan menurunkan viabilitas spora hingga 64,68%. Ekstrak jahe sebanyak 6-10% dapat menunda perkecambahan spora jamur Monascus isolat J2MA-D selama 1 hari dan menurunkan viabilitas spora hingga 89,47%.

Dodol is a Intermediate Moisture Food (IMF) which had water activity 0.7 – 0.79. It could be spoilage by fungi during storage especially xerophiles fungi. Ginger (Zingiber officinale) included of spices which had antifungal activity and usually added in food. Water ginger extract could be used as natural preservation agent to replaced chemical preservative in dodol. This research was carried out to study the effect of water ginger extract as natural preservation agent against mycelium growth and spore viability of dodol spoilage fungi. Ginger extract was used in this research was made from fresh gingers which were extracted with steril water ( 1:1 w/v) in blender. The ginger extract was filtrated with cloth , centrifuged (3000 rpm, 10 minute) and filtrared again with double layer Whatman no 1 steril paper. Spoilage fungi was isolated by direct platting method on Czapek Yeast Extract Agar medium with 20 % of sucrose (CY20S). The mycelium growth assay was done by inoculated of one point of spore suspension in the middle of CY20S medium which added by ginger extract and the diameter of colony was measured during incubation time. The spore viability assay was done by inoculated of spore suspension with spread plate method on Czapek Yeast Extract Agar (CYA) medium and the colony was calculated during incubation time. The incubation time was five days at 30oC and the concentration of ginger (Zingiber officinale) extract on medium assay were 0%,2%, 4%, 6%, 8%, and 10%. There were six isolated of spoilage fungi, three isolate belong to Aspergilus genera (J1B-A, J1MA-B, J1B-C ) and three isolate belong to Monascus (J2MA-D, J4MA-E, J4B-F ). The result of mycelium growth assay showed that addition of water ginger extract increased the inhibitor activity of mycelium growth. But, the addition of ginger extract until 10 % could not stop the growth of all isolate fungi. The result of spore viability assay showed that the ginger extract delayed the germination and decreased spore viability of spoilage fungi. Addition of 8 – 10 % of water ginger extract delayed germination of Aspergillus J1B-A for two day and decreased spore viability until 64,68%. Concentration water ginger extract 6 – 10 % also delayed the germination of Monascus J2MA-D for one day and decreased spore viability until 89.47%.

Kata Kunci : Jamur xerofilik, jahe (Zingiber officinale), pertumbuhan miselia, viabilitas spora