Create a custom block in org-mode that exports to latex and html

Question

I'm writing a long research org-mode document that I want to export to both LaTeX, ODT and HTML. The most important export environment is to LaTeX.

I would like to be able to specify an environment inside the org-mode document without specifying the language. For instance, I could write:

#+latex: \begin{acknowledgement}
...
#+latex: \end{acknowledgement}

But I would prefer to write something like:

#+begin_acknowledgement
..
#+end_acknowledgement

Is this possible?