Derivative (finance) In finance, a derivative is a contract that derives its value from the performance of an underlying entity. This underlying entity can be an asset, index, or interest rate, and is often simply called the underlying.
Examples. Preservatives are either natural or chemical. Examples of chemical preservatives include nitrates, sulfites, sodium benzoate, potassium sorbate, and propyl gallate. Common natural preservatives include salt, lemon juice (citric acid), vinegar (acetic acid), sugar, and certain spices.unction. Preservatives work in one of three ways. They can prevent growth of microorganisms by creating an environment hostile to them. They can block the process of oxidation that causes foods to turn rancid.
The chief preservatives in wine are alcohol and tannin. Both are entirely natural. There are very few organisms which will survive immersion in alcohol. It has therefore long been used as a sterilent in medicine. Alcohol is much more stable in wine than sulphur dioxide.