Have a time delay for the CIP mode control switch so that all flow promoters (including flow control device) do not operate during the CIP operation. from milk. When the injection occurs directly into the CLT: When the injection occurs between the CLT and the FCD: Another option is to valve the injection line out of the system by using sanitary mix-proof fail safe valves to isolate the injection from the HTST when the system is not running (FCD is de-energized). Keep records to show this testing has occurred. For example, ensure that the lines terminate and break to atmosphere at least two times the diameter of the largest return line above the maximum overflow point of the constant level tank. Ensure the FDD and the return lines are constructed of stainless steel and are in clean and good mechanical condition. Scientific Evaluation of Milk Pasteurisation 2 Following further studies on the thermal destruction of M. tuberculosis and other pathogens, a High Temperature Short Time (HTST) pasteurisation standard - 161oF (71.7oC) for 15 seconds - was included in the1933 edition of the U.S. Public Health Service Milk … Ensure heating plates are of sanitary design, constructed of stainless steel or other corrosion resistant material and are without any pin holes in the plates. Verify the effectiveness of this installation by disconnecting the pasteurized milk inlet piping to the regenerator during diverted flow and, with the vacuum equipment operating at maximum, check the piping for negative pressure. reduce the holding time below the required minimum. This device is a positive displacement type pump (may be a homogenizer). Install with a pressure tight seat against the inside wall of the pipe with no threads exposed to milk or milk products. Ensure ports (poppets) are visibly open during divert flow or shut down. temperature (Seconds)(°C) 1 81.6 2 79.0 3 77.6 4 76.5 5 75.7 6 75.1 7 74.6 8 74.1 9 73.7 1073.3 1173.0 1272.7 1372.4 1472.1 1572.0 High temperature-short time pasteurisation of milk integrity & assurance Include procedures for system start-up, sanitization, production and cleaning, and what to do if the critical factors (for example time, temperature, pressure differential) are not met. 0000015472 00000 n The data that support the findings of this study are openly available in internet at http://doi.org/. Drain raw product to the outlet before the outlet becomes uncovered. Install and operate an injection pump in a way that it will not: Reduce the pasteurization holding time below the required minimum. Temperature and time are critical factors required to achieve pasteurization. It is a good practice to identify the air lines. Cleary identify all switches on the STLR and any controls associated with the operation of the HTST unit. Seal the access to the computer's programming function. (The pen should have an easily accessible adjustment screw for this purpose.). Prevent the back-up and overflow of water and/or condensate from the vacuum condenser into the product vacuum chamber in the event of condensate pump failure, tailpipe failure, or power failure. Ensure the STLR is manufactured for HTST usage. Completely wash and sanitize the entire HTST system, piping and cheese vats, etc. Learn about our remote access options, Department of EIE, Easwari Engineering College, Chennai, India, Chemical Engineering Department, CLRI, Chennai, India. This will help in the identification of product flow and cross-connections. Increasing the line resistance by the addition of plates or piping will decrease the flow rate, increasing the holding time. Seal it at an established flow rate to prevent operation at a greater capacity than that which gives legal holding time. Verify no section of the tube is removable to the point of the inlet of the flow diversion device. The dynamics of the HTST process using the first‐principle method consisting of two inputs one‐output model is derived. Systems using an extended hold generally have two air operated valves, one at the inlet and one at the outlet of the extended hold line, that are controlled by the microprocessor in the HTST panel through a switch on the panel. Use the sensing chamber or an alternate fitting(s) upstream of the FDD as the other fitting. At each cleaning cycle, dismantle and manually clean and sanitize at the parts of the vacuum breaker that cannot be CIP. Ensure the medium side and the product side of the heating plates are free of gasket pieces and other foreign debris that might accumulate there. a single chamber vacuum system, with no direct addition of steam, installed downstream from the flow diversion device. This prevents operating the system at a greater capacity than that which gives the required holding time. If the calibration is consistently found to be out of adjustment, immediately identify and rectify the reason for the calibration problems. Prevent the lowering of the pasteurized milk level in the regenerator during diverted flow or shutdown. Process all pasteurized product first, followed by the raw product. Failure to achieve pasteurization could result in a microbiological hazard in the dairy products. 0000039617 00000 n Ensure the extension has a continuous upward slope of at least 2 % (2 cm per 100 cm). Perform tests upon installation and at least once every 6 months thereafter. Locate at least 76 mm (3 inches) from the product contact surface of the ferrule. Use two charts if operations extend beyond 12 hours.