I have used organic carrots finely grated and increased the quantity of carrots used, but still can't taste the carrot
You could try a few different tactics:
Use some roasted carrots. Roasting intensifies the flavour by removing water. Try not to brown them too much though, which will give them a burnt-sugar taste.
Use complimentary spices. Mace, which is the dried membrane that surrounds nutmeg, compliments and enhances the flavour of carrots very well. If you can't find mace, try nutmeg itself.
Reduce carrot juice. Simmer until syrupy and add to the cake. You might need a little more flour to compensate for the extra liquid.
You're not the only person experiencing this issue, there are reports that over the last few decades carrots have been losing nutrition and by extension, taste.
Here are some decisive things you can do to get more and more pleasant carrot taste of your carrots:
- Get the largest carrots you can (the more tasty part of carrots is the outer and lower part, bigger carrots have more of it).
- Use the bottom two thirds for your recipe (and save the top part for another dish).
- Buy purple or other colour carrots. Apparently, the orange carrot was selectively bred and domesticated by the Dutch Royalty. You may find all kinds of neat flavours in other types of carrots.
- Try the Mukum Carrot variety, they generally sweeter and may show up as more carroty ;)
- Carrots from colder climates are sweeter, particularly when temperatures go below freezing (the carrot plant makes sugar to prevent freezing and self preserve). See this document from Chef Dan Barber of the world-class Blue Hill restaurant.
The details what were the sweet and bitter taste of Organic Carrots come from are in this document.
If you want to go fancy, you could do an agar-agar carrot extraction and soak your finished cake with the carrot extract. http://www.instructables.com/id/How-To-GelatinAgar-Filtration/