E558 - Bentonite

Origin

Bentonite is a naturally occurring clay, primarily composed of montmorillonite, a phyllosilicate mineral. It is formed from the weathering of volcanic ash in the presence of water. The specific properties of bentonite vary depending on the proportion of montmorillonite and other minerals present, as well as the exchangeable cations (e.g., sodium, calcium) within the clay structure. Sodium bentonite swells considerably when wet, absorbing several times its dry mass in water. Calcium bentonite, on the other hand, does not swell as much.

Usage

In the food industry, bentonite is used as a processing aid, primarily for clarification and stabilization of beverages like wine, beer, and fruit juices. It acts as a fining agent, adsorbing proteins and other substances that can cause haze or instability. Bentonite is also used as a carrier for other additives and enzymes. Its adsorptive properties make it useful for removing unwanted components from food products. The amounts used are carefully controlled to ensure that the final product meets quality standards and regulatory requirements. It is also used in animal feed as an anti-caking agent and mycotoxin binder.

Side Effects

Bentonite is generally considered safe for use in food processing when used according to good manufacturing practices. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has established an Acceptable Daily Intake (ADI) of "not specified," meaning that, based on available data, the intake of bentonite at levels necessary to achieve the desired technological effect in food does not represent a health concern. However, excessive consumption of bentonite, particularly certain types, could potentially lead to gastrointestinal issues due to its swelling properties. Some bentonite clays may contain trace amounts of heavy metals, but these are typically within acceptable limits for food-grade bentonite. Regulatory bodies monitor bentonite sources to ensure compliance with safety standards.

Regulatory Status

Bentonite is permitted for use as a food additive in many countries, including those in the European Union (EU) and the United States. In the EU, it is designated as E558. Regulations specify the conditions of use and purity criteria for bentonite used in food. The FDA in the United States regulates bentonite under specific sections of the Code of Federal Regulations (CFR) pertaining to food additives and substances generally recognized as safe (GRAS). These regulations ensure that bentonite used in food meets certain quality and safety standards.