Kajian Teknologi Air Blast Freezer Untuk Mempertahankan Mutu Singkong Beku

Abstract

Singkong merupakan komoditas pangan lokal yang berpotensi dikembangkan menjadi produk pangan beku, namun proses pembekuan yang kurang tepat dapat menurunkan mutu fisik dan sensori. Penelitian ini bertujuan mengkaji pengaruh lama blanching dan metode pembekuan terhadap mutu singkong beku. Bahan yang digunakan adalah singkong jenis mangu pada umur panen 6 bulan yang diperoleh dari petani di daerah Pamijahan, Kabupaten Bogor, Jawa Barat. Singkong dikupas, dicuci, dipotong seragam (dibelah memanjang dan dipotong ±5 cm), selanjutnya diberi perlakuan steam blanching selama 2, 5, dan 8 menit, dibumbui, dikemas dalam plastik LDPE, kemudian dibekukan menggunakan Air Blast Freezer (-40°C) dan freezer konvensional (-18°C). Setelah penyimpanan beku, sampel di thawing pada chiller ±5°C selama 24 jam. Penelitian menggunakan Rancangan Acak Lengkap (RAL) faktorial dengan dua faktor, yaitu lama blanching (2, 5, dan 8 menit) serta metode pembekuan Air Blast Freezing (ABF) dan freezer konvensional dengan dua kali ulangan. Parameter yang diamati meliputi kekerasan, warna (chroma dan hue angle), kadar air, thawing loss, dan organoleptik. Hasil penelitian menunjukkan bahwa nilai kekerasan berkisar 2,09–4,06 kgf, chroma 11,87–15,93, hue angle 71,36–79,97°, kadar air 44,85–48,27%, dan thawing loss -4,33 hingga 2,59%. Lama blanching berpengaruh nyata terhadap kekerasan pada thawing hari ke-1 dan hue angle pada thawing hari ke-7, sedangkan metode pembekuan dan interaksi kedua faktor tidak berpengaruh nyata terhadap parameter mutu fisik. Lama blanching dan metode pembekuan berpengaruh nyata terhadap tekstur dan penilaian keseluruhan uji organoleptik, tetapi tidak berpengaruh nyata terhadap warna, aroma, dan rasa. Perlakuan blanching 5 menit dan pembekuan dengan metode ABF menghasilkan skor penilaian keseluruhan tertinggi pada uji organoleptik, sedangkan berdasarkan indeks efektivitas De Garmo, kombinasi perlakuan blanching 2 menit dan pembekuan dengan metode ABF merupakan perlakuan terbaik. Penelitian ini diharapkan dapat menjadi dasar pengembangan teknologi pengolahan singkong beku yang lebih efektif untuk mempertahankan mutu produk.

Cassava is a local food commodity with considerable potential for development into frozen food products. However, improper freezing processes may reduce its physical and sensory quality. This study aimed to evaluate the effects of blanching time and freezing method on the quality of frozen cassava. The material used was six-month-old mangu cassava obtained from farmers in Pamijahan District, Bogor Regency, West Java. The cassava was peeled, washed, cut uniformly by splitting it lengthwise and cutting it into pieces of approximately 5 cm, then subjected to steam blanching for 2, 5, and 8 minutes. The samples were seasoned, packaged in LDPE plastic bags, and frozen using an Air Blast Freezer (-40°C) or a conventional freezer (-18°C). After frozen storage, the samples were thawed in a chiller at ±5°C for 24 hours. The experiment employed a two-factor Completely Randomized Design (CRD) with two replications. The observed parameters included hardness, color (chroma and hue angle), moisture content, thawing loss, and sensory properties. The results showed that hardness ranged from 2,09 to 4,06 kgf, chroma from 11,87 to 15,93, hue angle from 71,36° to 79,97°, moisture content from 44,85% to 48,27%, and thawing loss from -4,33% to 2,59%. Blanching time significantly affected hardness on the first day of thawing and hue angle on the seventh day of thawing, whereas the freezing method and the interaction between factors had no significant effect on the physical quality parameters. Blanching time and freezing method significantly affected texture and overall acceptability in sensory test but had no significant effect on color, aroma, and taste. Blanching for 5 minutes combined with air blast freezing produced the highest overall acceptability score in sensory test, while the combination of 2 minutes blanching and air blast freezing was identified as the best treatment based on the De Garmo Effectiveness Index. The findings provide a basis for developing more effective frozen cassava processing technology to maintain product quality.