$re = '/(?<!^)(\d{1,2}\s?x\s?)?\d{1,2}((,|\.)\d{1,2})?\s?L?/iU';
$str = '25 Test Drink 60% 12x1,0L
Test Drink 60% 2x0,5
Test Drink 3 x 0,75 L
Test Drink 4x0,75 L
Test Drink 5 x 0,75L
Test Drink 66 x 0,75
Test Drink 0,75
Test Drink 0.75
7UP 12 x 1 L';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php