Dedicated frametitle in beamer presentation

Question

I'd like to create a key strong such that the title of a frame appears in orange on a gray background when I enter \begin{frame}[strong]. The problem is that the change becomes global. Is there a way to do so such that only frames with the strong key are modified?

\documentclass{beamer}

\makeatletter
\define@key{beamerframe}{strong}[]{%
  \setbeamercolor{frametitle}{bg=gray,fg=orange}}
\makeatother

\begin{document}

\begin{frame}
  \frametitle{My Normal Title}
\end{frame}

\begin{frame}[strong]
  \frametitle{My Strong Title}
\end{frame}

\begin{frame}
  \frametitle{My Normal Title}

  This title should be normal
\end{frame}

\end{document}