Just finished 2 of 200 litre jacketed mix tanks for a very satisfied customer. The water jacket is to heat the product to 62°C in 30 minutes. The agitator has metal detectable scraper blades, and the agitator is PLC controlled so that it runs for a short time [30 seconds] and then pauses for a set period and cycles through so as not to overmix the product. All complete system is wired to Cat 4 safety standards.
see videos of these tanks in operation via the following links