The Connection between food hygiene, safe food, control of environment and human evolution.

In nature food and water are the main driving force that motivate all living organisms. When food is freshly available animals invest little thought into the whereabouts of alternative food sources but when food becomes scarce or inferior in quality, animals have an amazingly strong and instinctive drive to find new and fresh food sources. The following article intends to portray how the search for nutrtious and uncontaminated food determined the evolutionary course of the primate that eventually became who we are today.

The earliest ancestors of mankind originated from the forests of Africa, They, like other primates browsed the trees and forest floor for food. Their diet was primarily a vegetarian one which may well have been supplemented with some animal protein. They may have searched for termites and other sorts of insects in trees and on the forest floor. They may even have hunted other smaller mammals such as monkeys whenever the opportunity arose.

Our ancestors walked on all fours because their body was suited for climbing trees. They moved around much the same as chimpanzees or gorillas. In time environments changed and much of the forest floor became submerged under water for most of the year. The water brought with it silt and seeds of plants that were new to the forest environment. A whole new source of food now emerged in the water. Much of this vegetation was edible and to our ancestors this abundance was too good an opportunity to pass up on.

Much of the time that our ancestors had formerly spent in the trees was now spent on the forest floor wading waist to chest high in water. In order to wade effectively in the water early man had to adopt a new posture, an upright one. If the water was deep our ancestors would have walked with his hands above his head. This meant that all the pressure of movement was now on the legs, feet and pelvis. The boyancy of the water would have helped to make this process less tiring. Over a period of time this form of locomotion caused the shape of the pelvis to change. The point at which the femur attached to the pelvis moved from the side to a point at which the femur was more or less perpendicular to the floor.

The feet also took on a modified shape. Once designed to grip tree trunks and branches the feet were now more suited to pushing off against the ground. Hands that were designed for swinging safely from branch to branch now became adapted to searching for plant roots, water invertebrates and fish. The hands became more sensitive and the position of the thumb aligned with the palm of the hand in order to increase the range of functions the hand could perform. Early man could now catch small prey in a pincer like motion and he could wrap all his digits around almost any object he found in the water.

This new found sensitivity of the hands would have helped early man to form an image of what he was feeling underwater in his minds eye. This ability to picture what the hands were feeling without the participation of any of the other senses probably caused early man to develop a larger brain.

Eventually the water that covered the forest floor receded and early man was left with a dilemma. No longer was he suited for life in the trees and the sources of food upon which he had relied for many hundreds or thousands of years were getting increasingly difficult to rely upon. This new situation only meant one thing, early man now had to improvise. Improvisation, in many cases means scavenging and that’s exactly what early man did. He became a browser gatherer and a scavenger.

Bush now became the habitat in which early man lived. Man avoided open ground to lessen the chance of being spotted by predators. Both his upright posture and living in a social group were a definite advatages in looking out for danger but also made him stand out in the landscape. Food was scarce and competition was great and man was at the lowest end of the pecking order. Man needed a quick and reliable solution, he had to find a way to suppliment his low calorie, low protein diet if he was to stand a chance of surviving as a species.

It was then that man discovered a breakthrough that was to become a turning point in human evolution. Our prehistoric ancestors discovered that the bones of dead animals left by carnivores contained an energy and protein rich source of food. It was bone marrow. If man could find enough predator kill sites he could find enough energy to survive.

Living in the natural world and being tuned into nature, early man, as is the case with other animal species, would have been quick to pick up upon signs of kill sites such as circling vultures. Vultures however do not circle during the night and it is during the night that most hunts take place. Here too there is a give away that can lead a scavenger to kill sites. The animal which discloses the location of kill sites is the Black Backed Jackal. This small canine is a very clever scavenger. Being too small to ever hope to drive off lions, hyenas, cheetas or African hunting dogs the black backed jackal bar in full knowledge that his bark will attract a competing species to the kill site. Early man would have heard the jackals call as well and would have waited on the wings for his opportunity to move in to claim his share.

Man would collect the bones and smash them open on rocks to get at the food source within. Eventually, by the arrival of homo erectus man was cracking bones open more effectively with specially designed flint tools. Collecting bones was sometimes a game of trial and error. Man might have had difficulty knowing for sure whether the bone marrow within the bones was still fresh enough to eat. From a food hygiene standpoint this was a risky business. Man had to develop a new strategy to ensure that the bones he was collecting were no more than a few hours old. By observing carnivore and scavenger habits man could arrive close to the scene of a kill when the carnivore was no longer very hungry. This meant that the level of aggression that the carnivore displayed was lower and the chances of being attacked considerably lessened.

The distance that man would have maintained between himself and the feasting predator would have coincided with the fight or flight response. This is the distance which animals in nature maintain when they want to observe the intentions of carnivores. It allows them to get a head start if they need to escape and it allows them time to launch a counter attack before the carnivore has got himself sorted out.

An indication of this distance can be seen in the Asiatic lion. This sub species will tolerate the presence of man at a distance of about fifty yards. This suggests that the lion was accustomed to man’s presence and provided he maintained this distance he was not under threat, generally speaking.

When a carnivore such as a lion finished his meal and moved on, the competition for the spoils would have been great. Jackals, hyena, vulture and other animals would have been waiting to stake their claim to the spoils. Man’s drive to get at the bones before the bone marrow spoiled became increasingly strong. Eventually man decided to take matters into his own hands and launch an offensive on the other animals trying to get at the carcass by throwing stones, sticks (or spears) and bones at any creature that dared to come near the remains. This could well have been the stage of evolution in which many animal species developed their inherent fear of man.

Over time early man would have become aware that it was less risky to follow some types of carnivores than it was to follow others. Canines also roamed the African planes. Following canines had a distinct advantage over following large felines. One such advantage is that canines preferred to hunt in places where felines and hyena were not present. Also, canines ate their kill very fast wolfing as much meat into their bellies in the shortest time possible to minimize the risk of being discovered by stronger predators and to take the partially digested food home to the cubs and aunties who were guarding the den.

In this situation man had the chance to move in on the carcass quickly, ensuring that the bone marrow inside the bones was still fresh. From a food hygiene standpoint this was an opportunity not to be missed. However, Canines in no way clean a carcass completely. They took only what they could carry in their stomachs. The meat was still left on the carcass would have presented man with the opportunity to feast upon meat which was tastier than bone marrow.

Canines leave meat on a carcass to keep other carnivores occupied long enough for them to get back to their den. The last thing they want is unwanted visitors.

As times progressed man’s intelligence and weapons arsenal increased. Man would have noticed that every hunt created confusion and panic. Where there is panic there are opportunities for opportunists. Some animals my have fallen or become entangled in undergrowth. It is quite possible that man, by knowing the lay of the land man could predict where animals were likely to encounter problems and, if he were in the right place at the right time he could easily take advantage of such opportunities. By using the potential of his big brain man could even have made such accidents more likely to happen by setting traps snares and other types of obstacles. By killing his own quarry man became increasingly less and less reliant on scavenging for food killed by others.

We all know that canines have a pecking order. The strongest always eat first. Lower ranking canines would have to wait their turn and if they got impatient they were often savagely reprimanded to remind them of their position in the pack’s pecking order.

The fact that man had a kill not far away would not have gone unnoticed by the canines. To my mind it is not inconceivable and quite likely that lower ranking individuals would have wandered over to the human camp to beg for an easy meal. Being in a state of elation after the hunt and knowing that the only reason they had a kill was because of the pack, man may have entertained himself by throwing less favored parts of the kill to the visitors. Could scenarios such as this have provided the conditions for the development of the unique relationship that developed between man and canine. On the one hand the dog was assured of it’s share of the kill without having to fight for it and risk physical harm and on the other hand man was assured of fresh food hunted down by the dogs.

In many parts of the world we can still see evidence of this prehistoric alliance between canine and man.

Could it be that the development of man’s relationship with canine species (the wolf) provided a key step in the advance of human evolution?

Food spoilage is really nothing more than a natural deterioration of organic matter. Everything in nature has to be broken down so that it can once again become part of the composition of soil. All of the various natural processes that participate in the spoilage of organic material are ultimately directed toward this aim.

Odor. Bad odor is a symptom of food spoilage. Foods that have a bad odor should be thrown out. We have already gone into the causes of foul refrigerator odor with regards the spilage of food. Yet there is another factor that we should take into consideration when talking about foul odors of food and that is that the odors can be soaked up by foods which have not spoiled and make them disagreeable to eat. In saying that, this problem does not only pertain to food which has spoiled. Nobody would like to eat a piece of cake that has adopted the odor and taste of smoked salmon, for instance. This is a major problem in the home kitchen. Luckily there are now products available that help to reduce the severity of refrigerator odor and foul taste transfer between foods. Now you can buy a refrigerator purifier that will prove invaluable in the prevention of refrigerator odor. This product is a real food saver. Small air filters for fridges are also available.

When we define food spoilage we can say that spoilage of food pertains any disagreeable change in the nature of food from the normal condition that we expect. These changes may compromise food hygiene. We are able to distinguish these changes through use of our senses. For instance, food may change visually, it may change in smell, to the touch or in taste. In saying that, we use some forms of what technically amounts to food spoilage, in a controlled way, to achieve a desired effect, as in Camembert cheese for instance. We crave the runiness of the cheese that is produced by specially selected bacteria and mould to produce an effect which many of us find pleasing to eat. Other examples of controlled food deterioration include Danish blue, Gorgonzola, Stilton and many other forms of cheese. We also tenderize meat such as game by jugging it or purposely speed up the deterioration process of meat when we inject lactbacillus bacteria into steak to mimic the ageing process. In short and in technical terms, food spoilage works for us easily as much as it works against us.

Nevertheless, food does spoil because once the fruit of vegetable has been picked or the animal has been slaughtered, the natural processes and defences of the organism are compromised and exposure to the outside environment causes a number of inevitable changes to occur.

The factors which bring about these changes include, air and oxygen, light, moisture, microbial growth factors and ambient temperature. Some of these changes indicate poor food hygiene and cross contamination and others point to chemical reactions and changes due to physical phenomina. Let’s go through the various causes.

Air and oxygen: Air comprises of about eighty percent nitrogen and about twenty percent oxygen. The level of oxygen in the air is too great for most organisms and therefore organisms have developed strategies to counter the harmful effects of oxygen. Our lungs are lined with a substance called surfactant. Surfactant provides a necessary barrier between the tissue of the lung and the oxygen in the air to counteract the caustic effect of the oxygen upon the lung tissue. Our bodies and the bodies of other organisms produce anti oxidants to counter other undesirable reactions of oxygen with substances called free radicals. By binding to free radicals, anti oxidants prevent reactions which are harmful to our bodies. When an organisms no longer has the support of it’s various physiological support systems, the chemical make up of the organism will start to react with the oxygen in the air.

Micro organisms which require the presence of oxygen in order to metabolize organic tissue, such as aerobic bacteria and moulds, are able to colonize those areas of the flesh which are exposed to the air. The will form colonies upon the food and start to metabolize the flesh of the organism and divide at a rate of one division every twenty minutes per bacterial cell. In some cases as few as one thousand bacteria can be enough to contitute a food hygiene risk.

Enzymes, particularly oxidizing enzymes, which react with oxygen also aid the process of food spoilage. In vegetables enzymes such as catase and peroxidase cause the familiar browning of the flesh of foods such as apples and potatoes. Enzymes are substances which speed up chemical reactions and enzymatic reaction with oxygen in organic matter causes the degeneration of the matter to hasten considerably. In cooking a rapid heat treatment known as blanching is used to cancel these enzymatic reactions. Enzymatic changes do not usually render food inedible but if combined with microbial infestation such as mould or certain bacteria the ingestion of such spoiled food would constitute a food hygiene risk.

Water: water is the most abundant substance in nature. All organisms are made up of at least seventy percent water. The water within an organism when it is alive is termed as bound water because it is chemically connected to other substances within the body. All living organisms maintain a certain level of chemical concentration. This is said to mimic the concentration of sea water from which all living organisms originate. Concentrated fluids flow around the cells and each cell contains within it a carefully controlled liquid environment. The balance between the concentration of the fluids which flow around the cell and the fluid which exists within the cell is carefully regulated by the central control system of the organism, whether it be plant or animal. In higher organisms this process is called homeostasis.

Once a plant or an animal has been cut into smaller parts, the tissues whose fluid environment was once carefully controlled are now exposed to the environment. When the organism’s flesh comes into contact with moisture a physical phenomenon occurs. All substances in nature try to match their concentration levels to other substances around them, This is called diffusion. The flesh of an organism, when exposed to water will soak up the water in an attempt to dilute the concentration levels within the flesh of the organism to the concentration levels around it. This may cause the cells of the organism to explode by being too full of water. This form of tissue deterioration is a major cause of food spoilage. This intake of moisture into the tissue of the food source is the perfect vector for micro organisms to infest it. This is a very good example of how food spoilage occurs and food hygiene breakdowns happen.

In addition, excess “free” water within or around the cell gives bacteria the perfect medium in which to operate. In bacterial terms this is like a super highway in which bacteria are able to spread throughout the flesh of an organism. Water within an organism can be controlled by a) dehydration, b) freezing or c by the addition of food preservatives.

Light: Spoilage of food which is caused by light is called photo degeneration. All food is exposed to light at some time or another. Light can be either natural light or artificial light. Light, like all other forms of energy is made up of different wave lenghts. At the outer ends of the light spectrum we have infra red and ultra violet light which can vary in intensity in different parts of the world. These forms of light radiation are known to be harmful and can cause dead and live tissue to react in negative ways.

Exposure to light sources can cause foods to change in nature. Pigments may change, as may vitamin levels, fats and proteins. In solid foods the density of the material such as in meat may block deep penetration of light and therefore the effects of light may only cause changes to happen on the surface of the product. In liquids light penetration can be much deeper and therefore the effects of photo degeneration can be much more substantial.

Microbial growth. Micro organisms play a vital role in the balance of nature. Bacteria and other types of microbes haves each evolved to fill a specific niche. Some bacteria have developed a symbiotic relationship relationship with living organisms and some have developed a parasitical relationship. Healthy organisms manage to keep parasitical bacteria at bay through their immune systems and homeostasis. However, parasitical bacteria are constantly on the look out for signs of weakness and it is their job to bring about the rapid demise of sick organisms and to ensure that they are re cycled back into the environment through the process of tissue deterioration and degeneration. In prehistoric times man did not store much food. He ate from hand to mouth and so food did not have much time to go off. Modern man, because of his lifestyle, needs to store food and to do this he needs to effect a different kind of environmental control in comparison to prehistoric man.

In a previous chapter I mentioned that psicrophilic bacteria can cause food spoilage at low temperatures. In cold climates landscapes freeze for many months and animals find it difficult to survive. Weaker animals die during the winter months and remain frozen until the beginning of the thaw in spring. Although thawed a carcass may remain too cold for many types of bacteria to develop and it is for this reason that certain bacteria adapted to this niche so that the detioration of the carcass could begin. This process helps to ensure that the period of time during which more pathogenic bacteria infest the carcass and hence spread into the environment is considerably lessened. This is the function and importance of psicrophilic bacteria in nature. We can control the undesirable effects of psicrophilic bacteria in our cold stores through the implementation of a good hygiene regime.

In general, sources of food contamination come from the environment particularly from, animal wastes, soil, water and air. Here the “Four stages of food hygiene” come into play. Great care must be taken to make sure that food comes from safe sources, that food does not come into contact with other bacterial sources, that bacteria does not have conditions for growth and that tools and work surfaces are kept free from bacteria. food hygiene regime and temperature is all critical here. Don’t make mistakes or cut corners and bacteria will not develop.

Temperature. Temperature is probably the single most important environment which we can control to prevent the spoilage of food. Temperature regulates several changes in the nature of organic matter. Firstly it slows down chemical reactions within the food. Secondly it can prevent the ggrowth development of bacteria or destroy bacteria through cooking, Temperature regulation can control the destruction of vitamins and prevent dehydration and ripening of food.

However, temperature need to be professionally controlled. Over freezing can cause surfaces to crack of the development of ice crystals at microscopic levels can puncture cells causing the flesh to become soft and pulpy. Pigment can be lost and chemicals within the food may react and loose much of their nutritious value. This process is commonly called freezer burning.

In cold stores vegetables and fruit are best held at temperatures of around 10 degrees Celsius. meats should be chilled to four degrees Celsius and frozen food should be stored at -18 degrees Celsius for a period not exceeding six months in most cases. Aaways make sure that you follow manufacturers storage instructions. If in doubt don’t be afraid to contact the manufacturer or importer to get their advise.

Food hygiene is a subject which is of concern to everybody in the world every day of their lives. To many people around the world the ability to find safe sources of food and water are very real questions of survival. Everybody has an interest in eating to maintain good health.

From a very early age we are taught that rancid food is bad for us and we posses physiological mechanisms which trigger very adverse reactions when we come across food which possesses qualities which do not suit those to which we recognizing as safe. Our parents teach us the guidelines which we use to appraise the edibility of our food and water.

Scientists have discovered that out prehistoric ancestors often scavenged for food but although they scavenged they still made sure that the food they ate was still quite fresh. Prehistoric man would follow carnivores as they hunted for food or would have followed other scavengers such as vultures which only eat fresh meat. By waiting for the carnivore to finish it’s meal from a safe distance primitive humans were able to quickly move in on a kill and eat the meat scraps that were still left on the bones and, seemingly, to eat the bone marrow inside the bones by developing the skill of crushing them with stones. Early man obviously competed with other scavengers for these spoils but smaller animals would have quickly learned that early man moved around with implements which could be used to attack. Namely the stones with which they split the bones to get at the bone marrow. This would have been the point in evolutions in which many animals learned to fear man.

By following carnivores to their kills early man would have been able to ensure that the meat he was eating was no more than a few hours old as as such was as fresh as was possible to hope for, given the circumstances of those primitive conditions. In order to ensure that he was second only to those top predators, man had to establish himself as second in the pecking order for food. Yet although primitive man was second only to the top predators in pecking order in one sense it would have been an absolute necessity to develop the skills necessary to control the environment around the kill zone for several reasons. The first reason the first reason would have obviously been to ensure personal safety. Another reason would have been having the ability to chase off the predator once he has eaten enough and was too tired to resist effectively. Yet another reason would have been to prevent the carcass being stolen by rival human tribes or other animal species. However one cannot dismiss that a major reason in establishing a high level of control around the kill zone and making a timely move in on the spoils would have been to ensure that they meat still left on the carcass was still fresh enough to eat. So this sense of timing would have been a key factor in the food hygiene regime of early man.

My personal estimation is that this time period would have been anything from one to six hours after the kill. We also know that prehistoric man had a much more robust immune system that we do today. Things that primitive man could eat to no ill effect would make us quite ill. The range of foods which he would have eaten was far more extensive that what we eat (with the possible exception of the Chinese). Cooking and sterilization of food would only become known to man after he attained the ability to make and control fire.

So from these facts we know that food hygiene, at a very basic level has always been a fundamental concern to mankind.

Question. Could the necessity to chase carnivores and other scavengers from a carcass have brought about the advent of designing and using weapons as we know then in more recent history? Could having an array of weapon choices have provided prehistoric man with the ability to further control a hunt scene by hunting alongside certain species of carnivores (such as canines) while both they and their quarry were distracted by the hunt? Could this possible situation have led to the eventual alliance between man and canine? Would the realization of the benefits of developing the skills needed to exploit such opportunities have played a key role in the evolutionary development of mankind and eventually lead to his gaining the ability of placing himself at the top of the animal kingdom hierarchy?