<?php

$text = 'Title: Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Snippet: Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Category: Lorem ipsum dolor sit amet, consectetur adipiscing elit.';

$line = preg_match('~(*BSR_ANYCRLF)(^Snippet:.*$)~m', $text, $matches) ? $matches[1] : NULL;
echo $line;