it solidfy by the temperature
To solidify
pineapple, kiwi, mango, gingerroot, figs and gauva are the fruits which will prevent gelatin from hardening.
Pineapple kiwi papaya guava mango
Gelatinase is an enzyme that breaks down gelatin by cleaving its protein bonds, leading to liquefaction of the gelatin. The enzyme hydrolyzes the gelatin molecules into smaller components, causing the gelatin to lose its gel-like structure and become liquid.
Ice can be added in place of cold water to help the gelatin mixture congeal more rapidly. The lower temperature of the ice helps to solidify the gelatin faster.
The term "CONGEAL" likely means to thicken or solidify, as gelatin does when it cools.
The proteins in the pineapple called bromelain will break down the strands of protein in gelatin that forms jello. Hence, the effect of a fresh piece of pineapple on gelatin is able to keep the gelatin liquidfied.
Refrigerating the gelatin cultures helps to solidify the gelatin, making it easier to observe any changes in the consistency (liquefaction) of the gelatin. It also slows down any enzymatic activity that may occur at higher temperatures, allowing for a more controlled observation period.
Gelatin is a reversible colloid, so yes, if you melt a set jello, it should set again when chilled. However, other ingredients, such as pineapple, may alter the gelatin so that it does not set.
Jell-O contains gelatin, a natural protein. When jell-O powder is mixed with hot water, the gelatin actually dissolves in the water. Once it cools, the gelatin begins to reform into the rubbery, jiggly mass we all know and love.
Gelatin is almost entirely protein. As pepsin is a protease, its job is to facilitate the break down of protein into amino acids. When the enzyme is boiled, it becomes denatured, which prevents it binding to the substrate. As a result of this, the digestion of gelatin cannot take place, so the digestion of gelatin ceases.