If you've dialed in your ratio, grind, and brew time and it still tastes off, look beyond your technique.
Bean-Related Problems
- Stale beans. Coffee peaks 7–21 days after roasting. After 30 days, flavors fade and it tastes flat. Check the roast date on the bag.
- Wrong roast level. Light roasts are naturally more acidic; dark roasts are more bitter. If you hate sour coffee, don't buy ultra-light roasts.
- Low-quality beans. Commodity-grade coffee can taste woody, rubbery, or just plain bad regardless of technique. Try specialty-grade beans from a local roaster.
Water-Related Problems
- Hard water. Water with high mineral content (above 250 ppm TDS) can make coffee taste metallic or chalky.
- Soft / distilled water. Water with too few minerals (below 50 ppm TDS) tastes flat and sour. Minerals in water are essential for proper extraction.
- Chlorine or off-flavors. If your tap water tastes bad, your coffee will too. Use a carbon filter or bottled spring water.
Equipment Problems
- Dirty equipment. Old coffee oils build up and go rancid. Clean your brewer, carafe, and grinder regularly.
- Bad grinder. Blade grinders and cheap burr grinders produce uneven particle sizes, causing simultaneous over- and under-extraction.
- Wrong filter. Paper filters remove more oils (cleaner cup); metal filters let more through (fuller, potentially more bitter). Match your filter to your preference.
