Evaluation of some analytical methods for determination of calcium oxalate in Amorphophallus muelleri flour

Abstract

The presence of calcium oxalate is the major obstacle in flour processing of Amorphophallus muelleri tuber since the calcium oxalate can induce skin irritation and is harmful to kidneys. The development of a rapid analytical method to detect calcium oxalate in Amorphophallus flour is required. This research was intended to evaluate the use of some analytical methods (FTIR, SEM-EDS, XRD, XRF, and titration methods) in calcium oxalate detection in Amorphophallus muelleri flour prepared from different treatments (soaking in water (W), solution of sodium bisulfite 1000 ppm (B), solution of sodium chloride salt 3% (S), solution of sodium bisulfite 1000 ppm and sodium chloride salt 3% (BS)). Results showed that the presence of oxalate in Amorphophallus flour can be detected in the FTIR spectra from the C=O group at a wavenumber of 1610 cm-1. SEM images confirmed that calcium oxalate in Amorphophallus flour existed as raphide crystals in which their quantity can be estimated by the EDS feature of SEM. The presence of calcium oxalate crystals in Amorphophallus flour can be differentiated from other salts present in the flour by XRD. XRF can be used as a rapid analytical tool to detect the presence of calcium oxalate in Amorphophallus flour. The potassium permanganate titration technique can be used as a reference method for other rapid analytical methods in detecting calcium oxalate in Amorphophallus flour.

Pengaruh Variasi Konsentrasi Gliserol pada Ekstraksi Glukomanan dari Umbi Porang (Amorphophallus oncophyllus)

“…Kadar kalsium oksalat pada glukomanan yang diekstraksi lebih kecil daripada hasil penelitian oleh Widari and Rasmito (2018), di mana perendaman umbi porang dalam NaCl 8% pada suhu 80 C selama 25 menit diperoleh kadar kalsium oksalat sebesar 0,65%, dengan penurunan kadar kalsium oksalat sebesar 90,9%. Sementara itu, pada penelitian yang dilakukan oleh Sarifudin et al (2022), diperoleh kadar kalsium oksalat sebesar 6,2% dengan perendaman umbi porang dalam larutan NaCl 3% pada suhu ruang selama 30 menit. Selain itu, pada penelitian yang dilakukan oleh Wardani and Handrianto (2019) diperoleh kadar glukomanan sebesar 0,39% pada glukomanan yang direndam dalam larutan asam cuka pada konsentrasi 20%.…”

Make a 5 Keyword, The Application of Natural Deep Eutectic Solvents (Betaine-Glycerol) for Isolating Glucomannan from Porang Flour (Amorphophallus muelleri Blume)

“…A conversion factor of 5.7 was used to determine the protein content. Ca-oxalate was determined according to Sarifudin et al [23].…”

Purification and separation of glucomannan from porang tuber flour (Amorphophallus muelleri) using microwave assisted extraction as an innovative gelatine substituent

“…However, calcium oxalate in porang tubers must be eliminated first by purification using 10 % NaCl [ 6 , 7 ]. It can cause kidney failure and skin irritation if it is continuously consumed in amounts above the daily allowance (50 mg/kg) [ 8 ].…”