Without the advent of refrigerators, the unreliable methods of storing food would not only cause problems for taste, but also health, even without rotting the methods to preserve some foods required use of chemicals that were particularly hazardous over time. Refrigeration eliminated much of this, and as a result has had a major impact on economy.
    The basic explanation for how a refrigerator works is a pipe going into a loop, where a refrigerant moves through this pipe by a condenser affecting the vapor pressure of the refrigerant, and this pressure difference through the pipe is what makes it move, and the cold part of the pipe region in the refrigerator is what takes away heat from the food in the fridge and freezer, cooling it. For the efficiency of a consumer refrigerator when you're buying one, one with an energy star label will indicate high efficiency, as well as other appliances. Refrigeration has become and likely will likely for as long as imaginable be the prime way to store food.
  
 In terms of future technology, although it seems like just sci-fi, there is research into "refrigerating" people, to keep their body in a halted state until undoing this process much, much, later in the future, making it a potential candidate idea for space travel. Perhaps one day it can be viable option for suspending a living biological system to be resumed again.