public function setEmail($email)
    {
        if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
            $this->_options['email'] = $email;
            $this->_options['hash'] = strtolower(md5(trim($this->_options['email'])));
        } else {
            throw new \Exception('The email is in an invalid format!');
        }

        return $this;
    }