There are two basic types of pectin, though there are many subtypes of pectin within the two basic types. High-methoxyl pectin is the form of pectin traditionally used for canning applications. It requires high amounts of sugar to gel and is very sensitive to acidity. Low-methoxyl pectin has been used in the food industry to create low-sugar jams because it does not require high sugar levels to gel. It is also less sensitive to acidity and requires calcium to gel. Most molecular recipes call for low-methoxyl pectin.