$(document).ready(function(){
var el = document.createElement('script');
el.type = 'application/ld+json';
el.text = JSON.stringify({ "@context": "http://schema.org", "@type": "Recipe", "name": "My recipe name" });
document.querySelector('head').appendChild(el);
});
<!DOCTYPE html>
<head>
<meta property="og:image" content="myimage.jpg"/>
<title>JSON-LD for a receipe</title>
<!-- this script is needed outside jsfiddle
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
-->
</head>
<body><div>
content of page
</div>
</body>
</html>
External resources loaded into this fiddle: