I'm getting some sour flavors and off-aromas in my bottled beer when they have more of one month in bottle. When the beers are young, they taste really good with full aromas, but even if I stored all the batch in the fridge, I can't hold the freshness.
Is any way to improve the freshness with beers like Pale Ale or Heifeweizen?
EDIT For example, I made a beer using Pilsener Malt and wheat, in boiling I added some orange peel and coriander seeds. The beer, after one week in bottle conditioning, has a lovely aroma and full flavor, no problem. After 14 days, the aroma was gone and the taste became flat and sour, also the head retention was going worst. This example is with wheat, but also with a Pale Ale the hoppy flavor and arome went to nothing.