Page 6 - Food&Beverages Solution Palm Oil
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UV-VIS Spectrophotometer Atomic Absorption Spectrophotometer (AAS)
Deterioration of Bleachability Index (DOBI) & Carotene Content Lead in Edible Oil
DOBI, the deterioration of bleachability index, is an analytical method to test the quality of crude palm oil by determining its oxidative Edible oils, probably the most widely used cooking ingredient in the world, are produced from a wide variety of basic ingredients,
status. The deterioration of bleachability index can be determined via a spectrophotometric method by the numerical ratio of including fruits (olives, coconuts, palm, etc.), nuts (walnuts, macadamia nuts, almonds, etc.), seeds (sesame, sunflower, etc.), and a variety
absorbance at 446 nm to absorbance at 269 nm. A value of less than 1.8 implies poor quality, while values greater than 3 signify high of plants (soy, canola, capsicum (peppers)). These oils are not only used for frying and baking, but are also consumed as food, serving as
quality. Carotene content is another key quality parameter, with greater values representing better quality. dressings and toppings, etc. With this wide consumption of edible oils, it is important to not only ensure their safety and non-toxicity, but
to make they satisfy quality specifications. Here, using the Shimadzu AA-7000 atomic absorption spectrophotometer and the GFA-7000
graphite furnace atomizer, we introduce an example of direct quantitation of lead in edible cooking oil in accordance with AOAC Official
DOBI value = Abs at 446 nm / Abs at 269 nm Method 994.02, Lead in Edible Oils and Fats – Direct Graphite Furnace Atomic Absorption Spectrophotometric Method.
Carotene content = Absorbance at 446 nm
The GFA-7000 graphite furnace atomizer supports heating at temperatures from ambient to 3000°C, and the high-sensitivity optical
sensor and digital temperature control system provide accurate temperature control over the entire temperature range from drying to
Anisidine Value atomization. In addition, the dual electronic flowrate control system permits independent setting of the argon gas flowrate to 0.01 L/min,
thus providing high-accuracy measurement with high sensitivity.
The Anisidine Value test is used to assess the secondary oxidation of oil or fat, which is mainly imputable to aldehydes and ketones, and
is therefore able to tell the oxidation "history" of an oil or a fat.
Furthermore, AnV analysis on oil is an indicator of excessive oil deterioration in the deep frying process.
Anisidine value = 100 × optical density at 350 nm resulting from reaction of 1 g of oil with
100 ml of solvent and anisidine reagent
Instrument Optics Parameters
Shimadzu UV-VIS Spectrophotometer Product Lineup Equipment :Atomic Absorption Spectrophotometer
AA-7000 + GFA-7000
Model Features Lamp current (mA) :10
Measurement wavelength (nm) :283.3
· Small footprint with compact design Slit width (nm) :0.7
· Wavelength scanning from 190-1100 nm BGC mode :BGC-D2
· DOBI program ready
· 6-series multi-cell option
· Wide range of programs including photometric, spectral, kinetics measurements, DNA/protein and
high-level multi-component quantitation.
· Data storage on USB flash drives
UV-1280 · Instrument validation functions Calibration Curve for Pb in Edible Oil
Temperature Program
· Stand-alone or PC-controlled instrument.
· Wavelength scanning from 190-1100 nm
· DOBI program ready
· High resolution satisfies the standards of wavelength resolution demanded by the European Pharmacopoeia
· Wide range of programs including photometric, spectral, quantitation, kinetics, time scan, bio method
and multi-component quantitation.
· Data storage on USB flash drives
UV-1800 · Instrument validation functions
· Universal, research-grade spectrophotometer
· Double monochromator can measure up to 8 Abs
· PC-controlled instrument
· DOBI program ready Atomization Stage No.6
· Measurement wavelength extended from 300 nm to 1400 nm with integrating sphere
· Transmission, absorption and reflectance measurement
· Validation software as standard
UV-2600/2700 Peak profile of Pb in Standard Solution
Reference: Application News A487 Direct Determination of Pb in Edible Oils by GF-AAS
Solutions for Palm Oil Analysis Application Notebook
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