Mayonnaise like Smegmo and Crisco is a hydrogenated fat; cottonseed oil is a common factor to all three. Indeed, the name Crisco derives from the intial sounds of "crystallized cottonseed oil". Note in the next few pages a mention of Candlebrow -- underscoring a tie-in between Mayonnaise and Smegmo.
It may be of interest to note that hydrogenation may have a symbolic use for Pynchon. The process entails bubbling hydrogen through oil in the presence of a metal catalyst such as nickel, platinum, aluminum at 248 to 410 degrees. Remnants of these metals stay in the finished product, and when consumed can lead to an increase in heavy metals in the human body.
Eating hydrogenated oils is like eating plastic. The body does not recognize that these molecules have been mutated and tries to use them as essential fatty acids. But they cannot perform the same function, and as a result hydrogenated oils can cause short circuits in the electrical flow that controls the heartbeat, nerve functions, cell division and mental balance. They also create free radicals (anarchists!) that are linked to cancers. Free radicals plus metal remnants are a major contributor to cancer, heart disease, immune system dysfunction, osteoporosis, depression, chronic fatigue, Alzheimers, and neurological diseases. It is estimated that over 200 million people have died prematurely because of the hydrogenated oils found in our diets.  Not to mention innocent bystanders killed by mentally imbalanced people whose imbalance may stem from the ingestion of hydrogenated oils -- there may be some underlying reality to the "Twinkie defense."