Arbitrage, there are many modes. You are talking about cross-species arbitrage.

It may be based on the expectation that vegetable oil is much cheaper than soybean oil now and may be higher than soybean oil in the future. Therefore, more vegetable oil and empty soybean oil, as long as the difference between vegetable oil and soybean oil goes up, you will earn.

There's another way. I think the recent trend and increase of vegetable oil is stronger than soybean oil, so buy strong and sell weak. But that's not the return of interest spread, like the way of multi-variety hedging.

Arbitrage/hedging risk is relatively small, but it is not without risk. The key is whether the difference between your bid and your bid is based on the analysis of industry changes and characteristics, or the performance of pure disk.