The several mustards I have in my refrig don't contain MAS or any of the "hydrolized vegetable proteins" that can be a euphemism for MSG. But I don't have French's or Guildens...I have imported Australian mustard and maille etc.
French's yellow is heavy on tumeric and short on mustard.
If I were in your position I would make some home made mayonaise ( unless comercial mayo doesn't bother him) and add some Coleman's dry mustard and tumeric to taste.
For a grainy mustard, get some brown mustard seeds and grind them....mix with a teaspoon of water to make a paste and add to mayo.
You can make your own emulsions with ground mustard seeds and oil and vinegar but I'm not sure it's worth the trouble.
I suggest you try other kinds of mustards....read the labels to find one without "natural flavors".
Linda C

From recipe-greeting cards.com:

French's Yellow Mustard (Copycat)

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4 teaspoons dry ground mustard
1/4 cup water
3 T white distilled vinegar
1/2 t flour
1/4 t salt
1/8 t salt (additional)
1/8 teaspoon turmeric
Pinch of paprika

Combine all ingredients in small saucepan over medium heat. Whisk until smooth. Bring to boil then simmer for 5 minutes, stirring often. Remove pan. Cover until cooled. Keep refrigerated.
Makes 1/4 cup.

Here's another copycat recipe. It's slightly different from the one Ginger posted. You could make up both recipes and see which one has the better taste and consistency. I'm curious about this topic, so I'd appreciate you posting back your results.

FrenchÂs Yellow Mustard

MAKES 5 (1-TABLESPOON) SERVINGS
4 teaspoons dry ground mustard
1/4 cup water
3 tablespoons white vinegar
2 teaspoons Wondra flour
1/4 teaspoon salt
1/8 teaspoon turmeric
Pinch garlic powder
Pinch paprika
1tsp. honey or sugar
1 tsp. oil

Combine all ingredients in a small saucepan over medium heat. Whisk until smooth. When mixture comes to a boil, reduce heat and simmer for 5 minutes, stirring often. Remove pan from heat and cover until cool.
Chill in a covered container.

Thanks! Never tried any with flour in them. That may be the texture issue solution. I don't trust any commercial products. So many things have MSG and say they don't. I feel like the food industry puts MSG into things so our taste buds will be so burned out that we won't notice the poor quality of things. But there are a few things that are the normal that family has gotten used to and I wanted to get as close as possible without the bad things.

Here is a pretty good mustard recipe. It is from Recipe4Living. http://www.recipe4living.com/recipes/mustard_dip.htm

Ingredients

* 8 oz. sour cream
* 8 oz. brown spicy mustard
* 8 oz. Miracle Whip
* 1 pkg. buttermilk Ranch Dressing
* 1/3 C. sugar
* 3 Tbs. horseradish
* 1/2 small onion minced

Directions

Mix and chill.

Yield: approximately 3 1/2 C.

Here is a link that might be useful: Recipe4Living Mustard

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