Page 6 - Food&Beverages Solution Palm Oil
P. 6

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
      6                                                                                                                                                                                                                                        7
   1   2   3   4   5   6   7   8   9   10   11