Losses Arising From Production

Losses

Today, although production techniques for different types of cheeses have been standardized at the industrial level by ripening milk with enzymes and cultures, it is known that quality standards have not been established for many local cheeses produced with traditional methods. Accordingly, cheeses of the same type are produced with different standards and qualities, especially in terms of flavor, taste and aroma, depending on the producer. According to these results, serious losses are also seen along with the production defects of traditional cheeses, and this brings with it storage and marketing problems. In addition, due to the problems, the traditional image of the local cheese is damaged and therefore, in addition to causing economic losses, it is inevitable that it will create a risk for public health.

Raw milk, which is the primary raw material in traditional cheese production, must be milked from healthy animals under minimum technical and hygienic conditions and cooled quickly.

In order to make quality traditional cheese varieties, it is necessary to use quality raw milk. If the raw milk is defective, it cannot be improved by any application during processing and the defects usually become more apparent. For this reason, it is important that raw milk is produced and processed in a way that is suitable from farm to table under conditions that will not reduce its quality or therefore the quality of the product. Therefore, in order to gain a healthy perspective on milk, the process from production to consumption must be considered holistically.

Highly nutritious and reliable cheeses can only be produced in businesses where business hygiene and sanitation are ensured and good production techniques are applied.

Because foodborne diseases that may occur due to disruptions in cheese production, which has an important share in dairy products, especially highlight traditional cheese consumption and operational and production errors.

It is known that risks in traditional cheese production are due to biological, chemical and physical reasons. For this reason, a series of control measures are taken during the acceptance of milk, the main raw material of traditional cheeses, to the enterprises, and this is an important element in the production of safe and high-quality traditional cheese. For this purpose, platform tests are carried out at the enterprise intake point after the production of high-quality raw milk is ensured.

These tests include tests such as somatic cell count of raw milk, total bacterial count, fat, protein, acidity, pH, veterinary drug residues, and presence of preservatives, thus controlling the entry of raw materials into businesses that may harm public health and quality of milk.

In traditional cheese production, especially in cheese varieties made without heat treatment, the dangers related to microorganisms are in the first place.

These types of traditional cheeses are exposed to staphylococcal enterotoxins due to Staphylococcus aureus toxins, and in addition to this, soft and semi-hard cheeses are exposed to fecal coliform bacteria and Escherichia coli bacteria due to inadequate hygiene. Again, enterohemorrhagic bacteria that produce verotoxins while Escherichia coli (EHEC) has been causing health problems that may result in death in risk groups since the 1980s, traditional cheeses produced from inadequately heat-treated milk are one of the important sources of this agent.

In fact, one of the most common pathogens encountered in traditional cheeses is Lysteria monocytogenes which can cause serious health problems that can even lead to death in pregnant women and newborns, as well as in other risk groups and healthy people. Listeria monocytogenes can be transmitted to traditional cheeses from environmental materials and processing surfaces on the farm, milk processing machines, unhygienic cheese brine, presses used in molding cheeses, etc.

Another pathogen important for food safety in traditional cheeses is Salmonella spp. Salmonella species can survive in environmental conditions such as drying, freezing and low pH due to their high resistance to environmental factors.

For this reason, inadequate hygiene and sanitation practices, faulty pasteurization, technological errors or use of low quality raw materials can develop during the production of traditional cheese varieties and survive for a long time.

Brucella spp is one of the other important factors that can create public health risks in traditional cheese production, and poses a great danger especially when raw milk from animals infected with brucella is used in its production.

Therefore, it is sufficient to apply a heat treatment of raw milk at a minimum temperature of 71.5ºC for 15 seconds, and also to reduce the use of fresh cheese and to provide sufficient fermentation and ripening time in acidified soft cheeses with strong lactic acid. Brucella reduces the risk of survival of spp in traditional cheeses.

Staphylococcus aureus is another common pathogen in traditional cheeses. While S. aureus is naturally present in raw milk, inadequate pasteurization or contamination from equipment and personnel are important sources of contamination. Other foodborne pathogens that can be transmitted from raw milk, the raw material of traditional cheeses, include Mycobacterium, Brucella melitensis or Brucella abortus, Campylobacter jejuni, Bacillus cereus, Yersinia enterocolitica and many other factors may be involved.

However, microorganisms such as Bacillus and Clostridium, which cause spoilage and quality reduction, premature swelling, color and taste disorders in traditional cheeses are among the important problems and risks of this type of cheese.

For example, yeasts and molds that cause spoilage cause bitter taste, bad smell and gas in foods as well as unwanted sensory changes. They can also cause some disorders such as porous structure formation in some types of cheese. During the storage period of traditional cheeses, it is often seen that mold types contaminated with improper hygiene and low-quality raw milk develop on the surface of traditional cheese.

Yeasts, along with molds, can also cause gas formation, putrefaction and bitter taste in traditional cheeses (Candida spp., Kluyveromyces lactis, Pichia amethionina biovar. amethionina and Debaryomyces hansenii).

Pseudomonas species that are contaminated by raw milk or other contamination sources can also develop rapidly and cause a sticky/mucous watery texture. In addition, while bitterness and rancidity are the most important flavor defects in cheeses, many of these defects can be caused by Pseudomonas species that produce heat-resistant lipases and proteases.

As a result, if contaminated raw milk, which is the raw material, is used directly or without inadequate heat treatment in traditional cheese production, quality loss or health hazards may occur in the ways mentioned. Therefore, the following practices are important for safe traditional cheese production:

• Raw milk must be traceable from its production and must be produced using good production practices.
• Care must be taken not to disrupt the cold chain of raw milk and it must be stored at these temperatures until used.
• The use of raw milk in traditional cheese production should be avoided and raw milk should be heat treated at a temperature of at least 72°C for 15 seconds to 1 minute.
• Starting from the production of traditional cheese to ripening, distribution, marketing and sales, all kinds of contamination should be prevented and practices requiring good hygiene and sanitation (tools, equipment, business, personnel, etc.) should be implemented.

Another important source of safety and defects in traditional cheese production is chemical hazards. Chemical risks can primarily occur through the use of contaminated feed, the ingestion of chemical compounds due to grazing on contaminated soils, or the application of veterinary drugs. Another source of contamination is chemical contamination that can occur at various stages of the dairy production chain.

Examples include dioxins in animal feed due to the illegal use of contaminated technical oils in Germany in 2010, the case of furazolidone in animal feed, and the melamine crises in China in 2008. The following section summarizes the various chemical hazards that can occur throughout the dairy chain.

Mycotoxins can be found in animal feeds due to molds growing and can pass into milk. The most important mycotoxins that are exposed to through dietary intake from dairy products are aflatoxins, ochratoxin-A, fumonisins, trichothecenes, zearalenone and cyclopiazonic acid.

Aflatoxins (B1, B2, G1 and G2) produced by Aspergillus spp. are the most commonly known, and especially Aflatoxin B1 (AFB1), produced by A. flavus and A. parasiticus, is the most toxic among aflatoxins. In ruminants, AFB1 is metabolized by the cow, resulting in the presence of aflatoxin M1 (AFM1) in milk, which is harmful to human health. In general, AFM1 levels in dairy milk in Europe are low.

Chemical health risks that may arise from raw materials in traditional cheese production include plant toxins that can be found in forage crops and wild grasses, especially pyrrolizidine. There are reports of poisoning in Europe due to consumption of raw milk contaminated with 1,2-unsaturated PAs. One of these reports is a case of hepatic failure in humans caused by 1,2-unsaturated PAs. An epidemic of veno-occlusive disease (HVOD) is known and the agent responsible for this epidemic has been reported to be goat milk.

In general, the amount of PA transferred into the milk of animals exposed to PAs is low and therefore milk does not contribute significantly to human PA exposure, but in this case the transfer reached levels that could cause disease. Furthermore, even if the transfer is low, it may still pose a human health risk due to the genotoxic and carcinogenic properties of the compounds.

Sometimes, these compounds can be found in milk due to the use of feed contaminated with pesticides. In the past, pesticides were widely used, especially in agriculture. Among these, especially organochlorine pesticides such as DDT, HCH, aldrin, dieldrin have created chemical hazards in milk. Other polar pesticides commonly used in agricultural production, such as glyphosate and chlormequat, may also migrate into milk. One of the reasons for the presence of chemical residues in milk is the lack of information on the recovery times of contaminated pesticides in feed given to animals.

For whatever reason, the risk of pesticide residues in raw materials should always be taken into consideration in traditional cheese production, and for this purpose, feeds of known origin and produced with good feeding practices should be used in animals.

Polychlorinated compounds are among this group. Biphenyls (PCBs), dioxins, furans, perfluorinated substances (such as perfluorooctane sulfonates PFOS) and brominated flame retardants play an important role. Traces of organic chlorinated compounds can sometimes pass into milk through their presence in animal feed or through environmental contamination of pasture. In traditional cheese production, the use of milk contaminated with these pollutants can cause serious problems in public health.

Another group of chemicals that contaminate milk is metal residues. Metal residues can pass into milk from metal containers used for milk and milk products, machinery and equipment, and utility water, as well as through feed.

Metal residues that pass through feed are elements such as copper, zinc, iron, tin, arsenic, lead, mercury, and cadmium. Exposing dairy animals to these substances also causes their milk to become contaminated. Lead, one of these pollutants, accumulates in bones, kidneys and liver. Although its transfer to milk is low, it is very important in high intakes through feed and respiration.

The effects of human exposure to lead include an increase in systolic pressure and neurotoxicity. Cadmium accumulates primarily in the liver and kidneys. Cadmium can be found in traditional cheeses from dairy sources.

Another important health risk in traditional cheeses is the residues of veterinary drugs used in animal treatments. In dairy cattle, antibiotics are mostly used to control mastitis. For this purpose, the EU states that the take-back periods of such drugs should be controlled. (Directive No 2001/82 / EC; 2010/37 EC).

Detergents and disinfectants are among the other chemical contaminants that have emerged as residues in milk in recent years. Quaternary ammonium compounds (QAC), trichloromethane (TCM) and hydrogen peroxide residues can be found in milk and its products due to inadequate rinsing of detergents and disinfectants used in cleaning equipment and tools.

Another new danger due to the use of food additives and processing aids in traditional cheese production is allergens. Milk itself is an allergen, but allergens can also be found in the substances used in cheese production. Products containing allergens should not be used in traditional cheese production, and if the business produces other dairy products containing allergens, these should be produced in separate areas and appropriate cleaning should be done to prevent cross-contamination.

One of the dangers in traditional cheeses is physical substances such as feces, metal, plastic, stone, glass, etc. Such substances can be encountered in traditional cheeses at every stage of production.

Therefore, in order to avoid biological, chemical and physical hazards in traditional cheese production, food safety practices that include good hygiene and good production methods must be established in large or small businesses, and within this scope, all people in the traditional cheese chain must be trained on food safety.

All over the world, a large part of traditional cheeses are made by treating milk with coagulating yeasts (enzymes), and different types of cheeses are produced with the curd obtained by this method.

For this reason, in traditional cheese production, rennet is an important additive after raw milk. Rennet can be of animal, plant or microorganism origin.

In order to produce a safe and high-quality cheese, the yeast must be clean and its strength must be in line with the cheese quality and yield. Since the rennet has a significant effect on the cheese quality, maximum care must be taken with the rennet in traditional cheese production. The technological (coagulation strength, proteolytic activity, enzyme retention rate in the curd), microbiological (hygienic quality) and biochemical (enzyme homogeneity) properties of rennet must be well known.

For this purpose, in traditional cheese production, contamination that may arise from yeast must be prevented and yeast must be supplied from officially approved suppliers to ensure a superior quality product.

On the other hand, organic acids (citric acid, lactic acid, acetic acid, etc.) and salt are also used in the coagulation of raw milk. Similarly, these must also be selected carefully.

In the production of many traditional cheese varieties, before the milk is fermented, starter cultures and/or combinations of microorganisms called starter cultures are added according to the type of cheese that has a regional characteristic. Starter cultures are added especially to heat-treated milk to increase activation and to give the cheese its unique qualities (structure, taste and aroma).

They also have effects such as preventing the development of unwanted microorganisms, increasing the effectiveness of the rennet, and easily separating the whey from the curd. For starter culture purposes, microorganisms such as lactobacilli, streptococci, pediococci, leuconostoc, yeasts, and molds are used.

In this context, it is important for the safe production and quality of cheeses that starter cultures be purchased from pure and approved companies.