Milk’s (Clean) journey:
Cowsheds to consumers
Cleaning of large equipment / machines in any industrial environment is a challenge, particularly when it relates to the manufacturing of consumables. In the food and related sectors, the need to clean the equipment and surrounding areas are paramount. Most modern units have adopted Good Manufacturing Practices (GMP) and Cleaning In Place (CIP) processes which are based on a systematic and strict timetable.
The cleaning of equipment is a perennial problem in any industrial environment, particularly where processes have pipes and tanks which require regular cleaning. CIP is an efficient and cost-effective automatic cleaning and disinfecting system carried out without taking the equipment apart. Simply put, the cleaning processes involve a pressure washing system which, by using detergents and sanitizers delivered via different attachments, effectively cleanses the work area making it ready for the next shift. The wash down system is simple & sophisticated and designed to suit the cleaning requirement of the product.
“In the changing production scenario where manufacturing is done in bulk, say, as much as 1.5lakh litres or more of milk processed for various products at-a-time, the cleaning of large silos and pipes becomes a challenge”, says Dr K K Pramanik, Manager-Quality Assurance of Gujarat Cooperative Milk Market Federation. “Cleaning in such units is not spring cleaning, spot cleaning or deep cleaning that can be done on a once or twice a day, weekly or monthly basis. CIP is a continuous cleaning process,”
Even a slight spill of milk can wreak havoc. When milk spills, it not only decomposes but causes instant odour. Cleaning becomes equally difficult and cumbersome. Hence, the best way is to control odour at the root than to prevent it later. “At Amul, we try and ensure there is no milk spillage at any place. It is better to find the source of odour and remove the source than to allow the odour to set in and then control it,” says Dr Pramanik.
A modern unit today has fully computerised automated systems that control the processing right from the opening of the valve to the running of the pump. These machines are equipped with CIP system which is PLC based (programmable logic controller).“Cleaning in the food processing plant, particularly dairy processing unit, involves four important aspects the cleaning agent, the temperature, the flow and the time. To maintain all these in the precise specification, we need the CIP systems. At a given temperature, with a certain flow and turbulence using a certain type of cleaning agent, specific cleaning is possible. The CIP systems which have conductivity meters, RTDS for temperature, flow meters… are the eyes and ears in the plant. This is connected to the PLC system.
“With every product, there are certain CIP recipes which are programmed to perform the various cleaning operations. For example, if you activate recipe one, it is programmed to drain the milk, recipe two to clean with fresh water, recipe three to clean with caustic at a particular concentration, then drain, then clean with water, then sterilize with hot water at 90oC for 10 minutes … until the system is clean and ready for the next batch. The system is allowed to cool and the milk is inducted into the system.” The conductivity meter reads the system once the water is flushed out after the wash and ensures that the system is ready for circulation.
This cleaning process is followed in all the dairy product manufacturing equipment. The CIP system is provided by companies like GEA, IDMC, Alfa Laval, Tetra Pak and others.
Besides, the actual production area, the basic GMP takes into consideration the surrounding area which should be clean, green and germ free. Machines like scrubber-drier and vacuum cleaners are deployed for the general cleaning of the surrounding area. Personal hygiene and cleanliness play a vital role and workers are trained to practise various hygiene requirements. Laundered and sanitised attire, clean & sanitised hands, foot hygiene and use of hand wash are some of the basic standards followed as part of GMP in the manufacturing units. “At Amul, the periphery cleaning is done by our trained workers who use Diversey scrubber-driers and cleaning solutions. We use hand sanitising solution of Diversey and also of Tetra Pak,” says Dr Pramanik.
The cleaning of general or surrounding area at many units have been outsourced to housekeeping contractors who follow the standards laid down to meet GMP requirements.
Clean India Journal visited two dairy processing units – Parag Milk Foods Pvt Ltd’s ‘Go Cheese’ manufacturing unit in Manchar (Pune) which is Asia’s largest cheese plant, and the government-owned Mahanand Dairy, Goregaon, Mumbai, which processes lassi, shrikhand, buttermilk and other products.