It depends entirely on how strict they are. There are many vegans who won’t drink most beer because the brewery uses isinglass (fish swim bladders) in the brewing process. There ARE special breweries who cater to this variety of vegan by using a different clarifying agent.
There are vegans who won’t eat honey because it’s an animal product, even though no animal was killed in the processing of it.
Kanicbird
Generally any animal too small to be seen with the naked eye can be ignored. There were questions of whether the things in the tap water were too large to qualify.
I should clarify that. Generally, under Jewish dietary laws, any animal too small to be seen with the naked eye can be ignored. However, the intent of that rule is that Jews don’t need to search through brocoli with tweezers and microscopes before eating it. If the Jew in question has made a genuine effort to clean all insects etc from food, and has prepared the food in accordance with other laws, it can be considered kosher. However, there is some question of whether NYC tapwater can be consumed, since it is known to be contaminated.
There is another law defining what percentage of a foodstuff must be contaminated before the whole thing is considered treif, nonkosher. AFAIK the purpose of this law is to prevent antiSemites from ruining a huge pot of mammele’s chicken soup by pouring in a few drops of pig’s blood. However, again AFAIK, this law does not apply to a manufactured product known to contain even traces of nonkosher ingredients. In the case of my Yiddishe mamme’s soup, the law prevents a large amount of food and effort from being easily ruined. In the case of a manufactured product, it’s usually just as easy to buy a kosher variety.
Re Sea Salt
I’ll have to look into the Jeiwsh view of certain micro organisms. I know that diatoms (their shellls are used in toothpaste, and in some pool filters) are viewed as plants. All plants are considered kosher. AFAIK fungi, monera, and protists are no longer classified by biologists as plants or animals. How Judaism has reacted to this, I don’t know. Considering that rabbis have weighed in on how to properly celebrate the sabbath and other Jewish holidays (which begin and end at sunset) while in spacecraft, space stations, or other planets, and that there are rabbis who have earned degrees in biology or chemistry to better analyze whether certain things are kosher, I’m sure at least one rabbi has written a paper on ‘From Two Kingdoms To Five, How Does It Affect The Jews?’
Shouldn’t vegans be ok with any organism without a central nervous system? After all, even a floating microorganism without a CNS is closer to plant or bacterian than an “animal”.
Isn’t the CNS the vital issue for a vegan?