With regard to the foods, the general principle is that they are permissible unless they are mentioned as haram with a clear evidence in hadith and Quran. Those foods should not be eaten.
But the problem is the use of yeast in these pickles.
It says in al-Mawsoo‘ah al-‘Arabiyyah, under the heading Khameerah (yeast):
Yeast is a substance that ferments the dough when making bread. Its effect is the formation of carbon dioxide which created bubbles that make the color of the dough lighter and makes the dough expand during baking and rise and increase in size. Yeast is also used to make beer, nabeedh, and other alcoholic drinks. The yeast that is used commercially is made from colonies of microscopic single-celled yeast organisms. Although there are more than 600 kinds of yeast, only a few of them are used commercially.
Based on that we conclude that it is not wrong to use yeast in pickles as the amount used is very little and it gets dissolved in them. Hence the effects of this yeast do not cause intoxication or languor. It does not harm a person and there is no wrong in eating the pickles made from yeast.
However, if too much yeast is used or if a person ate too much pickle that resulted in intoxication then it becomes haram to use yeast in those food items. If the one who ate a lot of these pickles would become intoxicated or tired, it is haraam to use the yeast in them or to eat anything to which yeast has been added in this way.
Thus it becomes clear that pickles made from permitted foods are permissible. It should be noted that the vinegar which is put with these products or that is produced by pickling these materials, comes under the heading of drinks that are originally permissible, and is a type of food that the Prophet (blessings and peace of Allah be upon him) ate and praised, saying, “What a good condiment is a vinegar.” [Narrated by Muslim, 2051].
There is nothing wrong with eating a bread that is made with yeast. The yeast (khameerah) that is added to the dough does not come under the heading of khamr (intoxicant) that is haraam, and does not have any effect of causing intoxication or languor, especially since cooking it with fire alters the yeast completely, so that it no longer has any effect.
Yeast makes bread easy to cook and help leaven it. Some people, however, say that it is khamr and is not permissible to use it.
This is not correct. There is nothing wrong with the use of yeast in the dough for the purpose of leavening it. It is because it has no effect on it at all. Moreover, the yeast does not cause intoxication if a person were to eat it. The basic principle concerning all foods and drinks and clothing is that they are permissible unless it is proven that they are haraam, because Allah, may He be exalted, says (interpretation of the meaning):
“He it is Who created for you all that is on earth. Then He rose over (Istawa) towards the heaven and made them seven heavens and He is the All-Knower of everything”
So there is nothing wrong with putting yeast in the dough to leaven it.
Fataawa Noor ‘ala al-Darb (tape 70, side b)
And Allah knows best.