Tamping espresso too hard can lead to several undesirable effects:
1. Over-Extraction
When you tamp too hard, the coffee grounds are compacted to the point that water struggles to flow through the puck. This causes the water to spend more time seeping through, resulting in over-extraction. Over-extracted espresso tastes overwhelmingly bitter, even for seasoned espresso lovers.
2. Inconsistent Extraction
Tamping unevenly can lead to an uneven coffee bed, where some areas are more compacted than others. This can cause channeling, where water finds paths of least resistance through the coffee puck. Some areas will be over-extracted while others are under-extracted, resulting in an inconsistent shot.
3. Slower Flow Rate
Excessive tamping pressure creates more resistance to water flow, slowing down the extraction process. This can lead to a longer extraction time, potentially resulting in a bitter, over-extracted shot.
4. Strain on Wrists
Continuously tamping too hard can cause sore wrists and strain from the excess pressure. Proper tamping technique and ergonomics are important to avoid repetitive strain injuries.
However, it’s important to note that within a certain range of proper tamping pressure (around 20-30 lbs), the impact on extraction yield and total dissolved solids (TDS) may not be significant. A study found no difference in TDS when comparing tamping pressures of 12 lbs, 22 lbs, 32 lbs, and 42 lbs.
The key is to tamp consistently, applying enough pressure to create an even, compact coffee bed without over-compacting. Proper grind size, dose, and other variables play a more significant role in achieving the desired extraction.
With CINOART Automatic Tamper PT2, you can make the tamping quickly & easily, and consistently. We also provide you alternative coffee tamper such as CINOART PTB-FI & CINOART PTB-MY.
