Popular Mechanics (South Africa)
LUBE SERIES PART 5:
Food contamination and machine maintenance
Food machinery needs oil too!
IN 1847, a Hungarian physician named Ignaz Semmelweis proposed an outrageous theory that was generally scoffed at by the rest of the medical community. He claimed that washing one’s hands saves lives.
Dr Semmelweis was working in a maternity clinic in Vienna at the time, where he noted that the first ward, which was run by doctors, had a mortality rate that was three times higher than in the second ward, which was run by midwives. The deaths were mostly of the mothers, and the cause was ‘childbed fever’.
Through a process of elimination, Dr Semmelweis discovered that the only significant difference between the two wards was the people who worked there, and he later proposed that the doctors themselves, who would often perform autopsies before examining pregnant women, were transferring some form of ‘cadaverous particles’ across to the would-be mothers.
Following his discovery, Dr Semmelweis instituted a hand-washing policy, which immediately reduced the mortality rate by 90%. He later expanded this policy to include all instruments that were used on patients in labour, and a short while later the mortality rate (related to childbed fever) dropped to zero!
However, despite the success of Dr Semmelweis’ hand-washing policy, the rest of the medical community in Europe rejected his theory, and it took many years for the practice, and germ theory, to gain widespread acceptance.
Fortunately, doctors and surgeons no longer doubt the importance of good hygiene; but even today, thousands of people die every year due to food-borne bacteria and contamination. In South Africa alone, more than 200 people died last year in the world’s worst outbreak of listeriosis thus far.
While this may serve as a grave reminder that stricter food-control laws are needed in South Africa (ours have been lagging behind those of Europe and the US), very little has been said about other forms of food contamination, chemical as well as biological, that may be present in our food.
Although health-and-safety laws are seen as priorities for the food and medical industries, the fact of the matter is that hygiene and standards of cleanliness are equally important on the workshop floor,
where machine lubricants have to perform the same function as any other lube (that of reducing wear and friction and resisting corrosion) while having the added task of being a ‘food-grade lubricant’.
Unfortunately, the term ‘food-grade’ can be misleading, as maintenance workers may then believe that the oil is edible and assume it poses no contamination risk. This leads to sloppy oil applications in which the oil comes into direct contact with the food.
Generally speaking, most lubricants that are intended for use within the food-manufacturing industry are categorised in one of four standards, namely H1, H2, H3 and 3H.
H1 Generally, when people speak of ‘foodgrade’ lubricants, they’re referring to those categorised as H1. However, it should be noted that these oils are still industrialgrade lubricants, except that they have been refined to be tasteless and colourless. H1 lubricants are used only in applications where ‘incidental food contact’ may occur. These incidents are also limited to trace amounts that may not exceed 10 parts per million.
H2 In contrast to H1 lubes, H2 lubricants can be used only where there is no possibility of it coming into contact with food. Most general-purpose lubes fall under this category, but there are restrictions that pertain to toxicity in the form of heavy metals and known carcinogens.
H3 These are lubricants that typically contain edible ingredients, such as corn, soybean or cottonseed oil. H3 lubricants are mostly used to clean and prevent corrosion on factory equipment.
The challenge with H3 lubricants is that, in certain environments, these oils turn rancid quickly and are just as susceptible as food to contamination and the growth of bacteria, yeast and fungi. So, in many instances, the use of organic oils poses an even greater risk of food contamination. 3H These are lubes that are generally used on grills, ovens, loaf pans, boning benches, chopping boards and other hard surfaces in contact with meat and poultry, to prevent the food from adhering to the surface during processing. This product is also acceptable as a lubricant with incidental food contact (H1) for use in and around food-processing areas.
So, why is the subject of ‘Food Grade Oils’ important? Well, to be blunt, in the South African context, far more awareness is needed in terms of what constitutes a ‘food-grade oil’, and of the fact that many oils are not edible.