Designation for the best possible state of ripeness of the grapes in the annual vegetation cycle of the vine. Ideally, the grape harvest should be carried out at this time or grape condition. The term maturation describes the state of ripeness from the point of view of the sugar or must weight (sugar ripeness) formed in connection with the acidity, whereby a distinction is made between early, full and overripe. In some cases, this is also referred to as technical/technological maturity. The grapes have reached a maximum of stored sugar. The concept of physiological ripeness only came into being in the USA in the 1990s and subsequently became increasingly accepted in Europe as well. Physiology as a branch of biology is the study of the physical and biochemical processes in the cells, tissues and organs of all living organisms.