PENGARUH METODE DAN LAMA FERMENTASI TERHADAP KARAKTERISTIK KIMIA TEPUNG UBI JALAR UNGU (The Effect Of Fermentation Method and Time On Physicochemical and Functional Characteristics Of Purple Flesh Sweet Potato Flour) - Reni Juliana; Elisa Julianti; Lasma Nora Limbong (Universitas Sumatera Utara, 2017)
ABSTRACT The aim of this research was to find the effect of fermentation method and time on chemical characteristics of purple flesh sweet potato flour. This research was conducted by using completely randomized design with two factors, i.e. fermentation method (F) : (natural fermentation; fermentation by yeast; fermentation by lactic acid bacteria) and fermentation time (L): (24 hours; 48 hours; 72 hours). The parameters analyzed were moisture content, acidity degree, anthocyanin content. The results showed that the fermentation method had highly significant effect (P<0,01) on moisture content, acidity degree, and anthocyanin content. The fermentation time had highly significant effect (P<0,01) on moisture content and acidity degree, had significant effect (P<0,05) on anthocyanin content. The interaction between the two factors had significant effect on anthocyanin content and had no effect on moisture content, acidity degree. Keywords: Chemical characteristics, fermentation, purple flesh sweet potato, flour ABSTRAK Tujuan dari penelitian ini adalah untuk mempelajari pengaruh metode dan lama fermentasi terhadap karakteristik kimia tepung ubi jalar ungu. Penelitian dilakukan dengan menggunakan Rancangan Acak Lengkap Faktorial, terdiri dari 2 faktor, yaitu metode fermentasi (F), dengan 3 taraf yaitu fermentasi alami, fermentasi dengan menggunakan ragi rotim dan fermentasi dengan bakteri asam laktat. Faktor kedua yaitu lama fermentasi terdiri dari 3 taraf, yaitu 24 jam, 48 jam, dan 72 jam. Parameter mutu tepung ubi jalar ungu yang diamati meliputi kadar air, derajat asam, dan kadar antosianin. Hasil penelitian menunjukkan metode fermentasi memberikan pengaruh berbeda sangat nyata (P<0,01) terhadap kadar air, derajat asam, dan kadar antosianin. Lama fermentasi memberikan pengaruh berbeda sangat nyata (P<0,01) terhadap kadar air dan derajat asam, dan memberikan pengaruh berbeda nyata (P<0,05) terhadap kadar antosianin. Interaksi antara metode dan lama fermentasi memberikan pengaruh berbeda nyata (P<0,05) terhadap kadar antosianin, tetapi memberikan pengaruh berbeda tidak nyata (P>0,05) terhadap kadar air dan derajat asam tepung ubi jalar ungu. Kata Kunci : Karakteristik kimia, fermentasi, ubi jalar ungu, tepung