Maslow's Hierarchy of Needs. Definition. Maslow's hierarchy of needs is a theory of motivation and personality developed by the psychologist Abraham H. Maslow (1908â1970). Maslow's hierarchy explains human behavior in terms of basic requirements for survival and growth.
When you use ice to cool the ingredients for ice cream, the energy is absorbed from the ingredients and from the outside environment (like your hands, if you are holding the baggie of ice!).
1 The faster an ice cream freezes the smaller the ice crystals will be. Tiny ice crystals translate to smooth ice cream without a noticeable grain, or worse, big, very noticeable pieces of ice.  Immediately pre-chilling a mix after taking it off the stove stops it from continuing to cook.