Smell, spoiled products

Malo-lactic Bacteria. Promptly separating the new wine from the thick layer of yeast and pulp particles is most important. Many wines are spoiled by procrastination. The yeast cells, if left in a thick layer, will begin to digest themselves and produce bad-smelling materials. Some breakdown products from this action have odors reminiscent of rotten eggs—the odor of hydrogen sulfide. Once the wine has acquired a rotten egg odor it is very difficult to remove it. 

Real-World Reading Link When fatty substances in foods spoil, they are referred to as rancid. Large molecules are broken down through redox reactions that result in foul-smelling products. The equation for this process is complicated but can be balanced using the same rules for simpler equations. 

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