To remember:

Hyperconjugation is the stabilising interaction that results from the interaction of the electrons in a σ-bond (usually C-H or C-C) with an adjacent empty or partially filled p-orbital or a π-orbital to give an extended molecular orbital that increases the stability of the system. [Further information][1].

**The proposed systems to take into account.**

Looking at the resonance structures (which is a synonym of [mesomeric effect][2]) of the propene

[![Resonance structures of propene][3]][3]

and acetic acid

[![Resonance structures of acetic acid][4]][4]

Therefore, in hyperconjugation analysis you need to look at the position of the electron density. Not the vicinal hydrogen. 

Moreover and with the aim to give a complete answer, the hyperconjugation of the acetic acid can be very well understood at [here][5].


  [1]: http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch04/ch4-3-2-1.html
  [2]: http://goldbook.iupac.org/M03844.html
  [3]: http://image.tutorvista.com/content/organic-chemistry/hyper-conjugation-propene.gif
  [4]: http://nonsibihighschool.org/intbasch9_files/aceticFC.png
  [5]: https://chemistry.stackexchange.com/questions/27799/hyper-conjugation-in-acetic-acid