Leverage browser caching for Laravel 5.1 application

Recently I was checking my web application loading speed (which is build using Laravel 5.1). And I came across Leverage browser caching. So I googled it to find a solution to this and I found a solution but it doesn't seem to work.

It was mentioned to add the following code:

<IfModule mod_expires.c>
  ExpiresActive on

# Perhaps better to whitelist expires rules? Perhaps.
  ExpiresDefault "access plus 1 month"

# cache.appcache needs re-requests in FF 3.6 (thanks Remy ~Introducing HTML5)
  ExpiresByType text/cache-manifest "access plus 0 seconds"

# Your document html
  ExpiresByType text/html "access plus 0 seconds"

# Data
  ExpiresByType text/xml "access plus 0 seconds"
  ExpiresByType application/xml "access plus 0 seconds"
  ExpiresByType application/json "access plus 0 seconds"

# Feed
  ExpiresByType application/rss+xml "access plus 1 hour"
  ExpiresByType application/atom+xml "access plus 1 hour"

# Favicon (cannot be renamed)
  ExpiresByType image/x-icon "access plus 1 week"

# Media: images, video, audio
  ExpiresByType image/gif "access plus 1 month"
  ExpiresByType image/png "access plus 1 month"
  ExpiresByType image/jpg "access plus 1 month"
  ExpiresByType image/jpeg "access plus 1 month"
  ExpiresByType video/ogg "access plus 1 month"
  ExpiresByType audio/ogg "access plus 1 month"
  ExpiresByType video/mp4 "access plus 1 month"
  ExpiresByType video/webm "access plus 1 month"

# HTC files (css3pie)
  ExpiresByType text/x-component "access plus 1 month"

# Webfonts
  ExpiresByType application/x-font-ttf "access plus 1 month"
  ExpiresByType font/opentype "access plus 1 month"
  ExpiresByType application/x-font-woff "access plus 1 month"
  ExpiresByType image/svg+xml "access plus 1 month"
  ExpiresByType application/vnd.ms-fontobject "access plus 1 month"

# CSS and JavaScript
  ExpiresByType text/css "access plus 1 year"
  ExpiresByType application/javascript "access plus 1 year"

  <IfModule mod_headers.c>
    Header append Cache-Control "public"
  </IfModule>

</IfModule>

in .htaccess inside the public directory. But I still get recommendation for Leverage browser caching. Please help me with this. I am unable to find a solution to this.

Sites where I checked for page loading speed are:

1. Google page speed
2. gtmetrix.com

Thank you

via Chebli Mohamed