What happens to melted tempered chocolate if it becomes too cold?

When melted tempered chocolate cools down too much, the cocoa butter crystals can begin to revert to a less stable form. Tempered chocolate has a specific crystalline structure that provides it with a glossy appearance and a firm snap when broken. If the temperature drops too low, those stable cocoa butter crystals can change back to an untempered state. This transition makes the chocolate dull in appearance and might cause it to lose its desirable texture and snap, resulting in a final product that may not set properly.

This transformation occurs because the precise temperature control is crucial for maintaining the temper of the chocolate; deviations can disrupt the delicate balance of the chocolate's crystalline structure, impacting both appearance and textural properties. Thus, the correct answer highlights the importance of temperature management when working with tempered chocolate, as improperly managing these conditions can lead to undesirable effects.