If you want to follow the USDA recommendations then 150 is too low, but if you want a beautiful, moist terrine 150 is about the highest I would go, IMO. Just make sure you are using pristine products and do all the grinding yourself, or are getting your ground meat from a smaller butcher how grinds in smaller batches. You can't eliminate all risk, but if you are careful, work cleanly and quickly you can reduce any risk to a very small factor.
__________________ From Man's sweat and God's love, beer came into the World-Saint Arnoldus |