PENGARUH PERBANDINGAN TEPUNG TERIGU DENGAN TEPUNG LABU KUNING DAN PENAMBAHAN RAGI TERHADAP MUTU ROTI TAWAR (The Effect of Ratio of Wheat flour and Pumpkin Flour and Yeast on The Quality of White Bread) - Dita Deviana Fadhilah; Rona J. Nainggolan; Linda Masniary Lubis (Jurnal Rekayasa Pangan dan Pertanian, 2017)
ABSTRACT This research was aimed to know the effect of ratio of wheat flour and pumpkin flour and percentation of yeast to produce the best characteristics of white bread and to introduce a new pumpkin product. This research was conducted using a completely randomized design with two factors, namely ratio of pumpkin flour and wheat flour; (95%:5%, 90%:10%, 85%:15%, and 80%:20%)and percentation of yeast; 1%, 2%, 3%, and 4%. The parameters analyzed were water content, ash content, fat content, protein content, carbohydrate content, fiber content, volume increase, organoleptic values (colour, flavour, taste, and texture). The results showed that the ratio of wheat flour and pumpkin flour had highly significant effect on ash content, protein content, fat content, fiber content, carbohydrate content, volume increase, colour, and taste. Concentration of yeast had highly significant effect on ash content, protein content, fiber content, volume, colour, and  taste, but had significant effect on texture. The 85%:15% proportion of wheat flour on pumpkin flour and 3% of yeast produced the better and more acceptable quality of bread. Keywords: Pumpkin, White Bread, Yeast ABSTRAK   Penelitian ini dilakukan untuk mengetahui pengaruh perbandingan tepung terigu dengan tepung labu kuning dan penambahan ragi untuk menghasilkan roti tawar dengan karakteristik terbaik dan untuk mengenalkan produk olahan dari tepung labu kuning. Penelitian ini dilakukan menggunakan rancangan acak lengkap dua faktor, yaitu perbandingan tepung terigu dan tepung labu kuning yaitu 95%:5%, 90%:10%, 85%:15%, dan 80%:20% dan konsentrasi ragi yaitu 1%, 2%, 3%, dan 4%. Parameter yang dianalisis meliputi kadar air, kadar abu, kadar lemak, kadar protein, kadar karbohidrat, kadar serat kasar, volume pengembangan, pengujian organoleptik (warna, aroma, rasa, dan tekstur). Hasil penelitian menunjukkan bahwa pengaruh perbandingan tepung terigu dengan tepung labu kuning memberikan pengaruh berbeda sangat nyata terhadap kadar abu, kadar protein, kadar lemak, kadar serat kasar, kadar karbohidrat, volume pengembangan, nilai organoleptik warna, rasa, dan tekstur. Penambahan ragi memberikan pengaruh sangat nyata terhadap kadar abu, kadar protein, kadar serat kasar, volume pengembangan, nilai organoleptik warna, dan rasa, namun berbeda nyata terhadap nilai organoleptik tekstur. Perbandingan tepung terigu dengan tepung labu kuning sebesar 85%:15% dan penambahan ragi sebesar 3% menghasilkan roti tawar yang lebih baik dan dapat diterima.   Kata kunci: labu kuning, roti tawar, ragi