Karakteristik Fisik Ekstrudat dengan Perlakuan Komposisi Bahan Grit Jagung-Tepung Kedelai dan Suhu Barrel Ekstruder

Vincentius Ferry Surya Dwinata, Dr. Joko Nugroho W.K., S.TP., M.Eng. ; Dr. Ir. Devi Yuni Susanti, S.T.P., M.Sc., ASEAN.Eng.

2023 | Skripsi | TEKNIK PERTANIAN

Jagung (Zea mays L.) merupakan bahan dasar dalam pembuatan makanan ringan ready-to-eat yang populer di Indonesia, namun memiliki mutu nutrisi yang rendah sehingga peranan bahan tambahan kacang-kacangan dapat menjadi suplemen protein. Penelitian ini bertujuan untuk mengetahui pengaruh komposisi tepung kedelai dan suhu silinder terhadap sifat fisik ekstrudat. Bahan menggunakan grit jagung (710 µm) dan tepung kedelai (500 µm). Produksi ekstrudat menggunakan mesin co-rotating intermeshing twin screw extruder. Rancangan percobaan menggunakan 2 faktorial, yaitu faktor komposisi tepung kedelai (10%, 20%, dan 30%) dan suhu akhir silinder (120 C, 130 C, dan 140 C). Parameter sifat fisik ekstrudat meliputi rasio pengembangan, bulk density, particle density, kekerasan, kadar air, water absorption index, water solubility index, dan warna. Hasil menunjukkan bahwa meningkatnya komposisi tepung kedelai dapat menurunkan sifat ekspansi sehingga memiliki kerapatan (bulk density dan particle density) dan tekstur bahan yang tinggi. Warna (yellowness dan chroma) meningkat seiring meningkatnya komposisi tepung kedelai dan menurunnya suhu silinder. Nilai lightness berada pada rentang 75,39-92,88. Nilai hue angle menunjukkan ekstrudat berwarna merah kekuningan (64,91-84,91). Water absorptoion index menurun seiring meningkatnya komposisi tepung kedelai dan suhu silinder, namun water solubility index semakin meningkat. Dengan demikian, tingkat preferensi konsumen menunjukkan perlakuan penambahan tepung kedelai 20?ngan suhu barrel 140 C menghasilkan makanan ringan sifat fisik yang baik.

Maize (Zea mays L.) is a basic ingredient in the manufacture of snack ready-to-eat that are popular in Indonesia but low nutritional quality. Thus, the role of legume addition can be a protein supplement. This study aimed to determine the influence of soybean flour ratio and barrel temperature on the physical properties of extrudates. The materials used were maize grit (710 µm) dan soybean flour (500 µm). Extrudate samples were produced using co-rotating intermeshing twin screw extruder. The experimental design used 2 factorials, such as the soybean flour ratio (105, 20%, and 30%) and barrel temperature (120 C, 130 C, and 140 C) as a factor. The effect of parameters on expansion ratio, bulk density, particle density, hardness, moisture content, water absorption index, water solubility index, and color of the extrudates were determined. The results showed that increasing the ratio of soybean flour can decrease the expansion ratio, thus it has an increased density (bulk density and particle density) and texture of the extrudate. Color (yellowness and chroma) increased as the soybean flour ratio increased and barrel temperature decreased. The lightness value is in the range of 75,39-92,88. Hue angle values showed yellow-red extrudates (64,91-84,91). The water absorption index decreased as the soybean four ratio and barrel temperature increased, but water solubility index increased. Therefore, the level of consumer preference showed that the feed composition of adding 20% soybean flour with barrel temperature of 140 C produces snack with improved physical properties.

Kata Kunci : grit jagung, tepung kedelai, ekstruder ulir ganda, sifat fisik ekstrudat