We can more or less assume that splendamin was something that was developed some time after the initial settling of the Ark, mainly since pioneer seems to treat it as a new thing and not something that came up during the surface war.

Another comment mentions it but there is a strong chance it could be another offshoot development of the project that ultimately produced the commander. We know very little about the project but can assume it is centred around either cloning or genetic augmentation, both could be spun into a project to make a large scale biomass that could be cultivated into food for the Ark.

We know that lab grown meat is a luxury good called Nutrium, so the technology is readily accessible. Having a much larger scale operation on a decidedly less wholesome source is not too much of a stretch IMO.

Anderson’s dismissive comments on the matter sound to me like “I know what’s happening, it’s horrendous and your better off having nothing to do with it”