Pengaruh Natrium Metabisulfit dan Proses Mekanik Terhadap Kualitas Talas Blok

Abstract

Kimpul Taro (Xanthosoma sagittifolium) contains high starch as non-rice carbohydrate source. Taro have itching  and  mucu caused by Calcium oxalate content. Its shelf life only 1- 2 weeks therefore, without treatment processing it would be difficult in transportation. There is absence  literature on taro block production. The research was done to decrease itching taste and mucus, simply in transportation and distribution,  so to lenghten of shelf life with processing treatments are soaking in 1% sodium chloride, soaking in 0,1% sodium metabisulphite, and its combination, and comparising processing of block taro between manual and mechanical press. The analysis was done on several parameters that influence to quality and shelf life of taro block such as water content, level of ash, starch, calcium oxalate, protein and sulphite residue, and organoleptic test by panelist. The result of research showed that soaking in solution of 0.1% sodium metabisulphite for 20 hours gave optimum result with content of calcium oxalate was 0.13%, residue of suphite was 1.39 mg/kg, level of ash 1.12%, 73,37% starch, protein 3.4%, and organoleptic test of colour and smell value of block taro were preferred by panelists and storage time for 8 months still in good condition. The making of  taro block with press mechanic systems had calcium oxalate content 0.065%, yield 21.38%, residue of sulphite 1.39 mg/kg, was able to decrease drying times for 7 hours with drying oven at 40 degC.

ABSTRAK

Talas kimpul (Xanthosoma sagittifolium) mengandung karbohidrat berupa pati yang cukup tinggi sehingga dapat berfungsi sebagai bahan pangan karbohidrat non beras. Talas menimbulkan rasa gatal dan berlendir yang disebabkan oleh kandungan kalsium oksalat. Umur simpan talas hanya 1-2 minggu. Oleh karena itu tanpa proses pengolahan akan menyulitkan dalam penyimpanan dan transportasi. Talas blok belum diproduksi, dan belum ada literatur yang menyatakan teknologi proses dan pengolahannya. Penelitian ini dilakukan  untuk mengurangi rasa gatal dan lendir, memudahkan dalam transportasi dan distribusi, serta untuk memperpanjang umur simpan dengan perlakuan perendaman dalam larutan garam 1%, larutan natrium metabisulfit 0,1%  dan kombinasi perendaman larutan garam 1% dengan  natrium metabisulfit 0,1%, kemudian membandingkan proses pembuatan talas blok secara manual dan mekanik. Analisis dilakukan terhadap kadar air, kadar abu, kadar pati, kalsium oksalat, protein dan sulfit tersisa serta uji organoleptik oleh panelis.  Hasil penelitian menunjukkan bahwa perendaman dalam larutan natrium metabisulfit selama 20 jam memberikan hasil yang optimum dengan   kadar kalsium oksalat 0,13%, sulfit tersisa 1,39 mg/kg, kadar abu 1,12%, kadar pati 73,37%, protein 3,4%, dan hasil uji organoleptik nilai warna dan aroma talas blok disukai panelis serta masa simpan 8 bulan masih dalam keadaan baik. Pembuatan talas blok dengan sistim mekanik menghasilkan kandungan kalsium oksalat 0,065%, rendemen 21,38%, sulfit tersisa 1,39 mg/kg, mampu menghemat waktu pengeringan selama 7 jam dengan oven suhu 40^oC.