When I cook vegetables in water, I usually add a little salt to the water. Apparently people a hundred-years-ago wondered whether it was a good idea to add baking soda when cooking vegetables.
Baking Soda in Cooking Vegetables and Fruits
The baking soda will soften the water in cooking beans or cabbage, and the vegetables will cook quicker and more thoroughly, but the alkali has a destructive effect on the vitamins present in these vegetables, and in all fresh foods. Scientists tell us that these vitamins are more important to nutrition than the foods themselves are when deprived of them, and that we lose the good of the food if the vitamins are destroyed. Try adding a little vinegar to the water for beans or cabbage; this will soften them quite as well, and our friends, the vitamins, are not injured by acids, only by alkalis.
Source: American Cookery (February, 1920)
A Hundred Years Ago 
My grandmother used to do this when cooking runner beans – I believe it was to retain that fresh green colour rather than speed up the cooking.
The color of beans does change when they are cooked. In some ways it sounds like a great idea to add baking soda to maintain the fresh green color. I may have to try this next summer when I have fresh beans.
A friend whose grandmother immigrated from Italian told me to add a pinch of baking soda to recipes like spaghetti sauce or chili so that it’d reduce the acidity of the tomatoes, making for a tastier meal. I do that but have never worried about destroying vitamins. Never ever thought of that, to be honest.
It seems like baking soda would be a good way to reduce acidity. I think that vitamins were a fairly new concept to people a hundred years ago, and as a result they worried a lot about them.
I’ve never come across this one. My grandmother would add a bit of sugar to tomato-based sauces (only a teaspoonful or so) but soda never was used except for baking or cleaning.
Many of the recipes that I have for tomato-based foods call for a little sugar which agrees with what your grandmother did.
I have read about baking soda for beans, but I never use it. Honestly, I prefer the long soak.
Like you, I just use water when soaking dried beans.
I’ve never heard of using baking soda to cook vegetables!
I may be trying to make connections when there are none, but maybe magazine articles like this one many years ago led to changes in how people cooked–and made the use of baking soda when cooking vegetables less popular.
I’ve never heard of this – and I’ll probably forget immediately! I never even remember to put salt in the water when boiling pasta or potatoes, so baking soda will likely never happen. The vitamins will never be in danger.
š I also sometimes don’t even put salt in the water. I’m thinking that it may be healthier to skip the salt, but it’s such a small amount that it may not matter.
I have never heard of adding baking soda either. I will give vinegar a whirl.xxx
It’s interesting to think about different things that can be added to water when cooking vegetables, though I don’t have enough of a science background to really understand how different additives affect color, taste, etc.
I only used baking soda in peas to keep them a lovely green,never used it in canning though as must things need acidity to can .
I hadn’t thought about it until I read your comment, but you are absolutely right that baking soda shouldn’t be added when canning because it is important to keep as much acidity as possible.
Thank you, Sheryl for the information, very helpful!
It’s nice to hear that you found this information useful.
I agree with Ally about adding it to tomato sauce. It just takes a pinch to help with the acidity of tomatoes.
This is good to know. Tomatoes can be very acidic.
The notion seems not to have weathered the test of time.
I know that I never heard of this cooking tip until I read the old magazine.