The Soviet Union ran such a program:

https://www.nytimes.com/1973/11/10/archives/soviet-plant-to-...

https://www.cia.gov/readingroom/docs/CIA-RDP91T01115R0001000...

The term to search for is "single cell protein."

There are newer approaches to making single cell protein from carbon dioxide and renewable energy instead of fossil oil, like Solein:

https://www.solein.com/

There are a few problems with turning oil into single cell protein:

- Microorganisms have small cells that reproduce quickly, which means a lot of nucleic acids in the dry mass, which is trouble for animals (including humans) that can't tolerate a very high purine level in the diet.

- The abundant cell walls of microorganisms also can cause illness when they're a high proportion of dietary intake.

- Feeding single cell protein directly to people has to overcome traditions of cuisine, even in cases where it doesn't actually make people sick. Indirect usage of SCP (e.g. feeding it to salmon, and then having people eat salmon) can overcome that hurdle, but then the cost per human-edible calorie goes up too.

In WW2 Germany invented a way to convert coal into an edible, butter-like substance. I think it was very inefficient though (70 to 1 input/output ratio).

I couldn’t find anything about this in a cursory google search, do you have any more information or links on this?

is there a lot of mineral oil out there? what motivates the suggestion of this particular precursor?

This is a bit nonsensical. How is doing chemistry to mineral oil to turn it into some other hydrocarbon sludge with mediocre nutrition more effective than the stupid hydrocarbon sludge we already have: Corn syrup?

Again, the ONLY reason there is still anyone, anywhere, who suffers from not enough food, is because people in the richest country on earth aren't even willing to spend a few million sending support to extremely needy countries.

Instead, we take a huge fraction of our entire corn crop, turn it into ethanol, and burn it. The primary reason we do it is to waste corn, so that corn prices are higher. We purposely make food more expensive, as a kickback to some real assholes.

World hunger could have been solved a century ago. No technology is required. Zero. At least until we have to figure out a reasonable way to make fertilizers more sustainable.

You know petroleum is actually expensive for a commodity, right? For the price of one barrel of oil, you could get an entire ton of iron ore, 0.8 tons of coal, 20 bushels of corn (about 1000-1200 pounds), 500 pounds of milk, 500 pounds of refined sugar, etc. Petroleum is an input to agriculture, but it enables staggering yield outputs per gallon of input. No amount of chemistry can ever compete with that for simple thermodynamics reasons.

Mechanized agriculture is so efficient that if you leave it to it's own devices it simply bankrupts itself every other year from oversupply. Damn near every functioning country artificially increases the price of basic agricultural commodities to ensure farms are stable. It's a massive handout to a cohort of people that nowadays are basically just very wealthy capital owners, but it also was the actual solution to famine, at least inside those countries.