“Pengaruh Larutan Asam Asetat dan Garam Dapur terhadap Pengurangan Kalsium Oksalat pada Tepung Porang (Amorphophallus muelleri)

Abstract

Menurunnya harga umbi porang memberikan dampak perekonomian bagi petani. Petani pada umumnya hanya mengolah umbi porang menjadi chips porang maupun tepung porang dengan kadar kalsium oksalat tinggi. Konsumsi kalsium oksalat dalam jumlah tinggi mengakibatkan gatal di tenggorokan, rasa panas di mulut, serta menyebabkan batu ginjal. Penurunan kadar kalsium oksalat dapat dilakukan dengan perendaman larutan garam dapur maupun asam asetat. Penelitian ini bertujuan mempelajari pengaruh jenis larutan, teknik perendaman, serta lama perendaman terhadap kadar kalsium oksalat dan karakteristik tepung porang. Perlakuan yang diberikan pada chips porang basah berupa perendaman dalam CH3COOH 20% dan NaCl 15%. Teknik selama perendaman adalah pengadukan dan tanpa pengadukan, masing-masing selama 60, 90, dan 120 menit. Penelitian dilakukan dalam dua tahap yaitu pembuatan tepung porang serta karakterisasi fisikokimia yang terdiri dari analisis kadar air, kadar abu, kadar glukomanan, kadar kalsium oksalat, dan nilai derajat putih. Hasil penelitian menunjukkan bahwa perlakuan pengadukan dan semakin lama perendaman mampu menurunkan kadar kalsium oksalat. Hasil penelitian terbaik diperoleh dari perendaman NaCl dengan pengadukan selama 120 menit. Perlakuan tersebut menghasilkan kadar kalsium oksalat 69,59 mg/100 g dengan persentase penurunannya sebesar 92,24% dibandingkan kontrol. Hasil karakteristik lain yang diperoleh yaitu kadar air 9,88%, kadar abu 9,23%, kadar glukomanan 43,11%, dan derajat putih 50,65%.

The decline in the price of porang tubers has an economic impact on farmers. Farmers generally only process porang tubers into porang chips and porang flour with high levels of calcium oxalate. Consumption of high amounts of calcium oxalate causes itching in the throat, burning sensation in the mouth, and causes kidney stones. The decrease in calcium oxalate levels can be done by soaking in a solution of table salt or acetic acid. This study aims to study the effect of the type of solution, immersion technique, and duration of immersion on calcium oxalate levels and characteristics of porang flour. The treatment given to wet porang chips was immersion in 20% CH3COOH and 15% NaCl. The technique during immersion was stirring and without stirring, for 60, 90, and 120 minutes, respectively. The research was conducted in two stages, namely the manufacture of porang flour and physicochemical characterization consisting of analysis of moisture content, ash content, glucomannan content, calcium oxalate content, and whiteness value. The results showed that the stirring treatment and the longer soaking were able to reduce calcium oxalate levels. The best research results were obtained from soaking NaCl with stirring for 120 minutes. This treatment resulted in calcium oxalate levels of 69.59 mg/100 g with a percentage decrease of 92.24% compared to controls. Other characteristic results obtained are 9.88% moisture content, 9.23% ash content, 43.11% glucomannan content, and 50.65% whiteness.