Go-Ferm Protect is a natural yeast nutrient that is added to the yeast hydration water before adding your selected yeast strain. Its complex formula provides your yeast with the proper sterols, unsaturated fatty acids and micronutrients needed to begin fermentation in optimal shape. The great thing about Go-Ferm Protect is that the proper nutrients and vitamins are introduced BEFORE the yeast is added to the must. This way 100% of the nutrients are available to your selected yeast strain and won't be stolen away by any indigenous yeast or bacteria that may be present in the must before your yeast can become established.