The inorganic residue left by ignition or complete oxidation of an organic substance in a food sample is known as Ash. Analysis of nutritional evaluation is done by determining the ash content of the food. Ashing is the primary step while preparing a sample for elemental analysis. The dry ashing method with a Muffle Furnace determines the ash content of a variety of food products.
Determination of ash and mineral content of foods is vital to be taken into consideration. Various reasons are:
- Quality of foods depends on the concentration and type of minerals they contain such as appearance, taste etc.
- Processing: It includes the mineral content of foods at the time of processing as it affects the physiochemical properties of foods.
- Nutrition: It includes minerals that are important to a healthy diet like sodium, calcium etc. and others can be toxic like aluminium, lead etc.
- Nutritional labelling: The concentration and type of minerals present should be provided on the label of the food.
A careful selection of sample should be made for all food analysis method whose composition represents that the food being analysed and to assure that its composition does not change before analysis. Samples of 1-10g are used in the analysis of ash content. Before performing ash analysis, samples having high moisture are dried to resist spattering at the time of ashing. High fat samples are defatted by solvent extraction to help the release of moisture and resist spattering. Other problems are contamination of samples by minerals in glassware, grinders etc. that come in contact with the sample at the time of analysis.
Dry ashing process uses Laboratory Muffle Furnace that maintains a temperature between 900°C to 1400°C. The equipment is used in general purpose heating in laboratories, ashing tests on rubber, fibers, wool etc. The heat treatment requirements for gears and several research facilities in physics and chemistry.
Applications are:
- Heat treating steel parts and gears
- Chemical analysis
- Glass blowing lab
- Plastic tensile strength test
- Ignition tests
- Agricultural
- Metal treatment
- Coal sampling etc.
The Muffle furnace adheres to standards such as ASTM and IS. Its main features are SSR based output controls. High level thermal efficiency by insulation means. Imported glass wool insulation. Advanced digital chip based PID temperature controller. Provides highly accurate test results under constant temperatures in the chamber. Auto tuning advance PID controller. User friendly machine used all over the world to perform heat treatment of small samples in laboratories.
