I’m sorry to hear about your son. He can’t afford to lose any more weight as he was underweight before he was assaulted. Unfortunately even with aggressive nutrition therapy, patients I have worked with often lost 10 pounds during the 6 weeks their jaw is wired.
Don’t think low-fat foods now, just offer him anything you are eating, but change the consistency to pureed or ground like baby food. Buy him whole milk rather than low-fat milk. Gelatin can be drunk as a liquid before it sets. If flavored gelatin sets, heat it up slightly and it will melt again.
Using your regular recipes, blend small amounts of foods you cook for the rest of your family. You can put anything including pizza or spaghetti with meatballs in a blender. Just thin food down with tomato juice or sauce, chicken or beef broth, fruit juice or milk rather than water. Gravy makes a good thinning liquid and has lots of flavor. Taste blenderized foods for flavor and add extra seasoning (salt, pepper, garlic, vanilla extract, etc) to make flavors stronger. Meat is a good source of iron, but when blended alone is quite grainy so blend casseroles with meat.
For instance, you could blend a piece of apple pie with apple juice or melted ice cream thinned with milk to get it to the right consistency. Macaroni and cheese can be blended with additional cheese sauce. For Easter, try blending ham and scalloped potatoes separately or together with some ham broth (from a simmered ham) or thinned cheese sauce. Blend canned fruit with extra fruit juice or even blend vegetables with cheese sauce (broccoli with cheese sauce). Have you thought of borrowing or buying a juicer for fruits and vegetables? These appliances often come with recipe books. Get creative, but work in small amounts, just enough for 1 meal. Experiment and taste.
Food that would normally be served hot, heat the blenderized version. Food that is normally served cold, keep refrigerated until serving. Add extra butter, margarine or oil to the blenderized food to boost the calories. Use half and half to thin milk-based foods.
Milkshakes with added malt would be OK, just let them melt to a thinner consistency. Try to find eggnog in the stores or make it yourself. Just remember to buy pasteurized eggs for homemade eggnog or heat the finished eggnog to 140 degrees then cool it in the refrigerator.
Is his jaw wired? If so, the doc may not want him to use a straw, but if he can use a straw, blend food so that it goes easily through a wide straw. Most people can put the straw through spaces created by missing teeth or between their teeth and inside cheek.
I wish there was a cookbook I could recommend, but don’t know of one. Call a local hospital or nursing home and ask them if they know of a good cookbook for pureed or dysphasia diets (swallowing problems often created by a stroke).
Let me know how he does.