Freshness is one of the most critical aspects of quality for specialty coffees. When stored, the characteristics of the green coffee beans undergo physicochemical changes. Both post-harvest and storage conditions are essential in delaying this modification process. For specialty coffees, the material of the coffee bag plays a key role in this process, along with the temperature, humidity, and luminosity of the environment. For roasted coffee, the conditions for maintaining freshness also depend on several parameters, such as the roasting profile, packaging material, and storage period. Virtually, the same factors that affect the freshness of green coffee beans also influence the roasted coffee beans. However, roasted coffee decays faster.

Since those changes represent the loss of quality, it is of interest to the specialty coffee industry to understand the parameters for evaluating the freshness loss in coffee. This course will address the fundamentals of coffee freshness, in addition to our sensory knowledge about these physical and chemical processes.

1) External factors that speed up the freshness loss in coffee:

1. temperature, humidity, and oxygen.

2) Aroma: Chemical composition of freshness:

1. Main freshness aromatic compounds.

2. Loss of aroma.

3. Production of defective aromas.

3) Physical factors that accelerate the loss of freshness:

1. Degassing.

2. Roasting profile.

3. Grinding.

4. CO2 loss rate.

4) Methods to evaluate freshness loss:

1. Aging: coffee origin and process.

2. Aging due to roasting profiles.

3. Packaging.

4. Sensory analysis.