The mechanical properties of gelatin gels are very sensitive to temperature variations, the previous thermal history of the gels, and time. These gels exist over only a small temperature range, the upper limit being the melting point of the gel, which depends on gelatin grade and concentration, but is typically less than 35°C (95°F) and the lower limit the freezing point at which ice crystallizes. The upper melting point is below human body temp., a factor which is important formouthfeelof foods produced with gelatin.The viscosity of the gelatin/water mixture is greatest when the gelatin concentration is high and the mixture is kept cool at about 4°C (39°F). The gel strength is quantified using the Bloom test.