Determination of Damaged Starch and Diastatic Activity in Wheat Flour Using a Flow‐Injection Analysis Biosensor Method

Abstract

Cereal Chem. 74(6):745-749The determination of damaged starch and diastatic activity in flour was studied using a flow-injection analysis (FIA) biosensor system. The system consisted of an oxygen electrode and an immobilized enzyme column containing purified glucoamylase and glucose oxidase immobilized on activated aminopropyl glass beads. The biosensor system has an optimum pH between 6.5 and 7.5 and an optimum temperature of 35°C for glucose measurement. The response of the FIA biosensor was linear up to 1.000 g/L of glucose with a lower detection limit of 0.025 g/L. Each assay took about 20 min, and the system showed good reproducibility (r = 0.998, n = 8). When applied to the measurement of damaged starch and diastatic activity in wheat flour, the results obtained agreed with those obtained using the conventional methods of measurement. This biosensor system is a rapid practical alternative for the measurement of damaged starch and diastatic activity in wheat flour.

Current research activity in biosensors

“…Haginoya et al determined starch damage and diastatic activity in flour by use of an FIA biosensor system comprising an oxygen electrode and an immobilized enzyme column containing glucoamylase and GOD, which were immobilized on activated aminopropyl glass beads [313]. The response of the FIA biosensor was linear up to 1.000 g L -1 glucose with a detection limit of 0.025 g L -1 .…”

A Maltose Biosensor for Determining Gelatinized Starch in Processed Cereal Foods

“…Moreover, our method can be readily automated with a flow-injection apparatus (Haginoya et al 1997), making it highly suitable for a large number of tests. From an economical point of view, the biosensor method is more convenient than the reference procedures because it uses low amounts of reagents and enzymes, inexpensive instrumentation, and unskilled operators.…”

“…Each sample was immediately stirred on a vortex mixer for 5 sec and then incubated at 40°C for 30 min. The a-amylase was first dialyzed to remove the stabilizing sugars (glucose, maltose) present in the commercial enzyme, as stated by Haginoya et al (1997) and Marconi et al (1998). Then 10.0 mL of diluted sulphuric acid (0.2%, v/v) was added to terminate the reaction and the samples were filtered (Whatman No.…”

“…The aim of this research was to develop a simple and reagentless electrochemical procedure based on the construction and assembling of an amperometric biosensor. Recently, as an alternative to the enzymatic-spectrophotometric methods, new sensing systems using biological molecules such as molecular recognition elements have been developed and applied to the measurement of polysaccharides and native enzymes in cereals such as starch, starch damage, b-glucan, and amylase activity (Rennerberg et al 1983;Haginoya et al 1997;Marconi et al 1998;Boyaci et al 2002). In particular, our research group (Marconi et al 1998) standardized an amperometric system for the determination of damaged starch in flour and semolina.…”