AbstractThe setting temperature of a pectin jelly is shown to be a determinate physical property, whereas the setting time is a secondary property dependent on temperature conditions. A technique for measuring setting temperature is described. As ordinarily manifested the setting temperature is subject to undercooling effects. It is shown that, as with jelly strength, PH conditions are a primary factor in regard to setting temperature, increase of PH causing a rapid fall of the latter; and that soluble solids concentration, pectin concentration, nature of buffer cations and heating have subsidiary effects. The setting temperature does not appear to be related to the jelly strength in any direct way, as judged by a comparison of the effects of the factors studied on the two properties.