DonkeyBoy is correct. This is a sign of mild infection. AND it's a a sign of dehydration. Both are a sign of bodily acidity.
If you avoid eating grains, cooked starch (aka burgers & fries) and ingest a lot of water, pineapple, fresh fruit, and fresh squeezed vege juices ... you'll see the problem (and the underlying infection) clear up.
You'll need to continue this for at least 3 weeks.
This little remedy won't hurt you but if it doesn't clear up after that then you definitely need to see a doctor for some kind of analysis cause you got PROBLEMS.
However, the extra enzymes from the fresh juice and fruit should alkalize your body and make your prostate healthier and happier!
The pineapple should make you semen smooth and sweet.
The water should make it ... well "watery" instead of overly thick.
And the absense of grain & cooked starch (NO PASTA DAMMIT!) should free up your liver to process things that will ultimately make your prostate work better.
Hope this helps! Happy jacking!