[davibu]

At this point, why not simply make your own? The simplest recipe would be n time better than an industrial one.

Look a the recipe: 150 g of seeds of brown mustard, 10cl of vinegar, 30cl of water, 10g of salt

Nothing really fancy, even my son could do it.

The same applies to homemade mayonnaise, 10 times better than the industrial one.

[scrumbledober]

I highly recommend anyone reading this to try making their own mustards. I make a couple large batches every year or two (whenever we run out) and jar them up in mason jars and everyone I know raves about them. One batch I made with a growler of hard cider from my local cidery that had been left in my fridge for too long and had gone sour. You can do all kinds of fun things making your own mustard and it's always worth it. Sometimes i'll throw some ginger in for a bit more punch.

[MagnumOpus]

Do you have any advantage in either the quality, price, or consistency of your water, salt, vinegar or seeds?

In 99.9% of cases the answer is "no" and procuring ready-mixed mustard is more convenient, cheaper, less messy and time-saving.

[Tade0]

The advantage of home-made food is that you have control over the ingredients.

Store bought mustard and mayonnaise contain such surprising ingredients like e.g. sugar or copious amounts of salt.

[bshimmin]

While I broadly agree with this, I would say that my own attempts at making mint sauce were fairly disappointing in comparison with shop-bought - Colman's mint sauce is an awful lot nicer than anything I was able to make, and (though I've never tried to make it) I bet their wonderful mustard is too.

You will probably also not be able to make at home anything all that similar to the mayonnaise you buy in a shop, though what you can make at home will almost certainly be equally as nice (my children were confused by the yellowish colour of home-made mayonnaise, which is sort of backwards since the confusing thing ought to be why shop-bought mayonnaise is white!).

[timcederman]

What store bought mustard contains sugar? I'm not aware of any, and if there are, they aren't common.

Also a little bit of sugar in mayonnaise is fine - in the US it usually relatively trace amounts to the most commonly sold ones in the Commonwealth.

[JasonFruit]

Another advantage is that making your own x from scratch is fun and satisfying. Mayonnaise, mustard, soda, barbecue sauce, gravlax, liver sausage — it's fun to see the things people buy ready-made, and know you have the knowledge and ability to do it yourself. Sometimes it's enough better to be worth the effort; sometimes, like catsup, you find that the store-bought is better — but you still have the fun of doing it and the satisfaction of knowing for sure.

[bookofjoe]

One word: Duke's

https://food52.com/blog/22456-we-taste-tested-8-mayos-and-li...

[bserge]

Why brown mustard specifically?

[utucuro]

Taste and spiciness. Yellow mustard seeds are milder and black mustard seeds are spicier. Brown seeds are usually in the middle. Most recipes usually call for specific amounts of each, once you know what you like, you can adjust them.