On the Pixian Doubanjiang production line, the chili powder and broad bean particles suspended in the viscous sauce are like reefs in the undercurrent, threatening the filling accuracy at all times. The filling head of the traditional sauce packaging machine often causes unstable material fluidity due to temperature fluctuations - the sauce condenses and blocks the nozzle at low temperatures, and the oil separation destroys the ratio at high temperatures. The pulse constant temperature filling technology developed by ply-pack is opening a breakthrough for the industry with precise temperature control logic.
The core of this technology lies in the dynamic temperature compensation system. When the filling head contacts packaging containers of different materials (glass bottles, PET bottles, composite film bags), the built-in 24 sets of thermocouples will scan the ambient temperature at a frequency of 30 times per second, and achieve precise temperature control through the following three-stage regulation:
.Preheating stage: 3 seconds before the filling starts, the filling chamber is heated to 38±1¡æ to make the bean paste and other sauces containing solids reach the best flow state.
.Pulse constant temperature: During the filling process, 5 heating powers (50W-200W) are automatically switched according to the change of material viscosity to ensure that the sauce flow rate is stable in the golden range of 0.8-1.2L/min.
.Gradient cooling: After the filling is completed, the system cools down in steps at a rate of 2¡æ per minute to prevent the residual sauce at the bottle mouth from forming a wall due to sudden cooling and shrinkage.
In the actual test of a compound seasoning company in Leshan, after the sauce packaging machine equipped with this technology continuously filled 2,000 bottles of pepper oil, the standard deviation of the uniformity of pepper particle distribution dropped from 12.3% of the traditional equipment to 4.7%, truly achieving the process goal of "every bottle is like hand-made".
For "extreme" materials such as Pixian Doubanjiang with a solid content of more than 35%, the technical team specially designed a double-circulation temperature control module. The outer stainless steel pipeline is connected to a 45°C constant temperature water bath, and the inner filling cavity is precisely controlled by a nano-ceramic heating film. When a leading enterprise in Sichuan used this equipment to fill 500g of Doubanjiang, the standard deviation of the filling accuracy was stable within ±0.5 grams, which was 60% higher than the old equipment.
What is more noteworthy is the chain effect brought by dynamic temperature compensation. On the production line of a small and micro enterprise in Yibin, the equipment can automatically identify the temperature changes in the workshop caused by the temperature difference between morning and evening, and adjust the heating strategy accordingly. The difference in solid sedimentation rate between bean sprout sauce bottled at 3 a.m. and the same batch of products produced at 12 noon was reduced from 8.9% to 1.3%, which completely solved the customer complaint of "taste deviation in the morning and evening" that has plagued the company for many years.
This technological breakthrough is not only reflected in the data level. In 2023, the pulse constant temperature filling technology was officially certified by the Sichuan Sauce Food Association. The expert group pointed out in the acceptance report: "This technology has achieved three major leaps-from experience temperature control to data temperature control, from single-point temperature control to global temperature field management, and from manual intervention to adaptive adjustment." At present, 37 Sichuan sauce companies in the country have passed the export food qualification review based on this technology, and their filling data have been accepted by the food and drug supervision departments of many countries such as the European Union and Southeast Asia.
Standing in the R&D laboratory of ply-pack, through the observation window of the filling test machine, you can see the chili flakes slowly rotating and sinking in the constant temperature sauce, like a precisely choreographed dance. This technological innovation, which started with the problem of filling bean paste, is now extending to more categories such as pickled peppers, fermented black beans, and spicy oil. As the technical director Zhang Gong often said when debugging the equipment: "We are not controlling the temperature, but the soul of Sichuan flavor."
