Activated Bleaching Earth

Activated Bleaching Earth for purification of Edible oils

Bleaching earths are often regarded as salt of the earth.Before Edible oils can be safely.Consumed, they have to be processed in order to remove impurities, both for commercial and health purposes.

A process known as bleaching involves the use of bleaching earths or clays. The term itself is misleading as colour removal is not the most important purpose of the bleaching process. Vegetable oils contain contaminates that adversely affect the performance, appearance and taste of the oil. In order for it to be used in edible applications, the oil must meet high quality standards that require the removal of various impurities.

The bleaching process essentially removes some colour from the oil; reduces how much chlorophyll and carotinoids the oil contains; removes soap, gums and trace metals; and decomposes oxidation products. Bleaching is performed prior to other processing

What are bleaching earths?
Oils are bleached using a powdered, surfactant material. Simply put, the powder is mixed with water, and then added to the oil where they absorb unwanted impurities before they are removed from the oil again, taking the impurities with them.

Bleaching earths are generally composed of up to three types of clay minerals: bentonite, attapulgite and fullers earth The minerals act as absorbers with capacity being dependent on mineralogical structure and properties, such as surface area, particle size distribution, porosity and surface activity.

Bentonites or fullers earth are a soft stone with the capacity to absorb substances dissolved in water and other liquids. The minerals have been formed over time due to the natural adaptation of volcanic ash