This reduces the shelflife of the meat by up to six days and is due to the fact that spoilage bacteria multiply much more rapidly. Microbiological spoilage and contaminatio n of vacuum. Other than sporeforming bacteria, all bacteria, parasites and viruses are killed quite easily with heating to 160f. Because the acc includes the organisms responsible for spoilage of meat.
Microbiological spoilage of meat and poultry products. Spoilage microorganisms an overview sciencedirect topics. Comparative proteomics of meat spoilage bacteria predicts. In cases where microbial growth occurs without gas production, spoilage will only be apparent once the pack has been opened. All raw foods contain microorganisms that will eventually spoil and break down the food. Meat spoilage the shelflife of meat and meat products is the storage time until spoilage. For the past 10 years, we have been attempting to understand the precise mechanisms by which meats suoh as ground beef undergo microbial spoilage at. Most are harmless, many are highly beneficial, some indicate the probable presence of filth, disease organisms, spoilage and a few cause disease. Instead, the bacterial population will consist mainly of lactic acid bacteria. This may be achieved 1 by excluding or removing microorganisms. Bacteria are the most important microorganisms to the food processor. Meat and meat products provide excellent growth media for a variety of microflora bacteria, yeasts and molds some of which are pathogens jay et al. Most common spoilages of microbial origin are known as flat sour spoilage, thermophilic anaerobic ta spoilage and putrefaction. Microorganisms such as molds, yeasts, and bacteria can grow in food and cause spoilage.
Food packaging under different modified atmospheres mas has become a common method to counteract deteriorative effects of long time storage of meat, e. There are many factors affecting the length of time meat products can be stored while maintaining product safety and quality. Spoilage of meat and meat products food microbiology. Pathogenic microbial species contaminating meat from the gastrointestinal tract are salmonella enteric strains, yersinia enterocolitica. Microbiological spoilage of fruits and vegetables 9 table 2 fungal fruit pathogens a 2004 annual u. There was a time when spoilage problems were the major concern of the meat microbiologist. Microbial growth and metabolism depends on various factors including. Spoilage microorganisms in fresh meat and poultry may be controlled by antimicrobials of microbial or animal origin, other than lab bacteriocins. Like meat, fish and other seafood may be spoiled by autolysis, oxidation or most commonly by microorganisms. Without such microorganisms, the earth would accumulate dead animals, plants, and other nondecayed matter. Preservation usually involves preventing the growth of bacteria, fungi such as yeasts, and other microorganisms, as well as retarding the oxidation of fats. Typically, the bacteria responsible for the spoilage of meat are those that.
Microbial fish spoilage and its biochemical changes. Extremely perishable meat provides favorable growth condition for various microorganisms. Foods of muscle ongm are sensitive to contamination and support growth of microorganisms involved in spoilage and foodborne illness. It also generally contains bacteria, including those that can cause diseases. Overlap of spoilageassociated microbiota between meat and. Because of this high potential for spoilage, the historical record reveals that early civilizations used techniques such as salting, smoking, and drying to preserve meat mack, 2001. Scientific opinion growth of spoilage bacteria during. Pdf on jun 1, 2018, asim faraz and others published microbial spoilage of meat find, read and cite all the research you need on. When the pure cultures of the bacterial isolates were inoculated into freshly prepared and sterilized cans of curried vegetable, sliced potato and mixed fruit, all of them proved to cause harmful effects to a lesser or greater extent. The point of spoilage may be defined by a abnormal bacterial ievel, an unacceptable offodour, off flavor or appearance.
The spoilage fish is the result of a series of change brought about in the fish tissue immediately post mortem by the action of endogenous enzymes autolysis, microorganisms, primarily bacteria and chemical reactions such as oxidation of lipids. Meat, a rich source of the protein and fat, low in carbohydrate content and with sufficient water activity, supports the growth of both spoilage and pathogenic bacteria. The microbiology of meat spoilage masointernational. Keep raw food totally separated from cooked product. Describe the typical bacterial growth pattern, and explain important factors affecting microbial growth. Spoilage of canned foods with diagram microbiology. Show full abstract minimally processed fishery products including fresh meat for retarding microbial growth and enzymatic spoilage. The influence of environmental factors product composition and storage conditions on the selection, growth rate and metabolic activity of the bacterial flora is presented for meat. Lipid oxidation, protein degradation and the loss of other valuable molecules are the consequence of meat spoilage process. Spoilage is the process of food deterioration leading to a reduction in its quality, to the point of not being edible for humans. Spoilage is also influenced by temperature not only air but temperature has an important influence on the type of spoilage to be expected in meat.
Pdf on jun 1, 2018, asim faraz and others published microbial spoilage of meat find, read and cite all the research you need on researchgate. In this article we will discuss about the microbial contamination of meats. Major spoilage organisms in raw meat and poultry are pseudomonas spp. Lactic acid bacteria, lactobacillus sake, shelf life, sensory changes, decontamination, vacuum packaging, sausage. Spices and other food condiment are commonly used to garnish food in nigeria. Spoilage is caused by the practically unavoidable infection and subsequent decomposition of meat by bacteria and fungi, which are borne by the animal itself, by the people handling the meat, and by their implements. The shelflife depends on the numbers and types of microorganisms mainly bacteria that are initially present and their subsequent growth. Viruses and parasites, such as tapeworms, roundworms, and protozoa, can cause foodborne illness, but they are not capable of growing in food and do not cause spoilage. The first part of this essential new book looks at tools, techniques and methods for the detection and analysis of microbial food spoilage with chapters focussing on analytical methods, predictive modelling and stability. Fresh meat has a high water content that is favorable for the growth of microorganisms. High postrigor meat ph is often caused by stress on the birds during growout or transportation.
Describe how certain microbes are used in food preservation. The microbial spoilage of canned food is classified as caused by thermophilic bacteria and mesophilic organisms. These effects are due to growth of spoilage microorganisms, found as initial contaminations on meat. The spoilage of meat occurs, if the meat is untreated, in a matter of hours or days and results in the meat becoming unappetizing, poisonous, or infectious. Biogenic amines are formed by decarboxylation of amino acids during manufacturing and storage periods of sausage through the action of substrate. Spoilage of meat products occurs generally in three types. Meat spoilage microorganisms although a range of microbial taxa are found in meat table 1, its spoilage in countries in which meat is stored under refrigeration is caused by relatively few of these organisms table 2. Raw meat and poultry are highly perishable commodities subject to various types of spoilage depending on handling and storage conditions. Growth of spoilage bacteria during storage and transport. Meat preservation helps to control spoilage by inhibiting the growth of microorganisms, slowing enzymatic activity, and preventing the oxidation of fatty acids that promote rancidity. Spoilage and preservation of food encyclopedia of life. Meat spoilage mechanisms and preservation techniques. The animals naturally carry bacterial species like salmonella and e.
Bacteria and yeasts typically result in slime formation, bad odors, rancid flavors, and discoloration grey, brown, or green. Bacterial groups on fresh unpacked meat the most frequent bacteria to occur on fresh meat are bacteria of the genera acinetobacter, pseudomonas, brochothrix, flavobacterium, psychrobacter, moraxella, staphylococcus. Introduction to the microbiology of food food technology. Bacteria must grow and reproduce to substantial numbers to cause a decrease in caselife. One example discussed above with nisin is lysozyme, which together appear to demonstrate synergy against meat spoilage lab, such as lact. Scenario of food spoilage worldwide the issue of food losses is of high importance in the efforts to combat hunger, raise income and improve food. Microbial growth to large numbers is a prerequisite for meat spoilage that can be considered an ecological phenomenon, encompassing the changes of the available substrata during the proliferation of bacteria 5, 6. Table 1 shows the chemical composition of fresh raw and processed meat. Higher numbers of spoilage bacteria on the chicken immediately after processing, translates to more rapid spoilage. Bacterial spoilage of meat and cured meat products. These bacteria include those arising both from animals and from the slaughterhouse or meat processing environment.
Meat spoilage mechanisms and preservation techniques science. Colour of meat is the first impression to the consumer and indicates the meat freshness or meat spoilage while the other sensory evaluations, like meat odour, come next. Food spoilage microorganisms focuses on the control of microbial spoilage and provides an understanding necessary to do this. Meat processing meat processing preservation and storage. Special forms of spoilage which adversely affect the meat 62. Prevention of spoilage and preservation of food, principally requires exclusion of microbial activity. The factors that are considered to have the main effect on the speed of spoilage and the shelf life of fresh meat are intrinsic factors initial number of psychrotrophs present on the meat surface, water activity, the ph value. Indications of microbial food spoilage vary with the microbes involved and the time. Bacteria associated with the spoilage of refrigerated meat products, causing defects such as sour offflavours, discolouration, gas production, slime production and decrease in ph, consist of b. Pdf meat spoilage mechanisms and preservation techniques. Lactic acid bacteria chiefly of the genera lactobacillus, leuconostoc, streptococcus, brevibacterium and pediococcus are present in most meats, fresh or cured and can grow even at refrigerator temperatures.
Foster stated in a report to the meat industry research conference in 1977. There are thousands of species of bacteria, but all are singlecelled and fall into three basic shapes. Beef products contain low levels of spoilage bacteria after processing. Fundamental food microbiology usda food safety and. In an attempt to study the microbial spoilage of canned food seven bacteria were isolated from seven different spoiled canned foods collected from various sources. Meat is also very much susceptible to spoilage due to chemical and enzymatic activities. Mechanism and detection of microbial spoilage in meats at low. Introduction to the microbiological spoilage of foods and beverages 3 ta b l e 1 percent loss of the united states food supply from primary production through con sumption abstracted from ers.
Meat processing preservation and storage britannica. The contaminating bacteria on the knife soon will be. The important contamination comes from external source during bleeding, handling and processing. Meat and poultry spoilage of meat pdf free download. The role played by bacteria in meat spoilage at refrigeration temperatures has been studied since the 1930s jay et al. Extended refrigeration may have the growth of pseudomonas, acinetobacter, moraxella and causes spoilage of fresh meat. Microbial growth, oxidation and enzymatic autolysis are three basic mechanisms responsible for spoilage of meat. Analysis of spoilage as measured by bacterial and chemical. Describe basic mechanisms and indications of microbial food spoilage. During bleeding, skinning, and cutting, the main sources of microorganisms are the body parts of the animal and the intestinal tract.