What are the applications of food hazard analysis in baked goods?

Baked food refers to a large category of food products that are shaped and cooked using cereals as the main raw material and baking processing techniques. Baked food is rich in nutrients, bread, cakes and other products have high water content and short shelf life, while mooncake sales are seasonal and the production period is very concentrated. In addition, the scale of production enterprises of these products varies, and many of them are street stores, restaurants and taverns, etc. Therefore, the safety problem of baked food becomes very prominent. Hazard analysis of raw and auxiliary materials

The raw and auxiliary materials of baked foods are mainly flour, grease, sugar, eggs, milk powder, additives, various fillings, etc. Their quality directly affects the quality of the products.

1.1 Biological hazards
Flour and oil are easily contaminated by mold, they can cause mold food poisoning, aflatoxin produced by Aspergillus flavus is a strong carcinogen. Warm, humid conditions are conducive to the growth of molds and the production of toxins.
The standard moisture content of flour should be less than 14.5%. If the moisture content of purchased raw materials is high, or the humidity of the storage environment is too high, it is easy for flour to develop mold. Oil seeds contaminated by molds and their toxins also contain toxins in the oil extracted, of which peanuts are most susceptible to contamination by Aspergillus flavus.

Fresh cow’s milk contains a large number of bacteria, in 4 ℃ below the bacterial reproduction rate is slower, the quality of cow’s milk to maintain better. Once cow’s milk is contaminated with staphylococcus, it can cause food poisoning by proliferating and producing enterotoxins in a suitable environment.

Fresh eggs are susceptible to spoilage when stored at high temperatures in summer. Fresh eggs are susceptible to Salmonella contamination, so utensils in contact with eggs must be cleaned and sterilized extremely carefully. Microorganisms such as salmonella can be killed during baking, but they can usually be found on the eggshells, so great care must be taken in sanitation if eggs are beaten in a bakery.

Sugar is susceptible to bacterial contamination. Fillings, which consist mainly of various animal meats and nut plants, are susceptible to bacterial contamination. Analyzed from a microbiological point of view, all these ingredients are high risk food ingredients and are susceptible to food poisoning.

1.2 Chemical hazards
The chemical hazards in baked food raw materials come from: pesticide residues, heavy metal content exceeding the standard in agricultural raw materials such as flour, oil, etc.; veterinary drug residues in livestock raw materials such as eggs and milk powder; the excessive and abusive use of food additives such as preservatives, colors, antioxidants, flavors and fragrances; and the use of corrupted and deteriorated fats and oils as raw materials. When packaging materials and containers are in contact with food, the chemical components therein may enter into the food. For example, the surface of mooncakes is high in oil content, and the migration of fat-soluble harmful components should be prevented.

Oils and fats stored at room temperature for too long will produce oxidative rancidity and hydrolytic rancidity. Hydrolytic rancidity increases the acid value of fats and oils, and oxidative rancidity increases the peroxide value of fats and oils. Long-term consumption of rancid fats and oils can lead to weight loss, developmental disorders, liver enlargement, and rancid fats and oils can also cause acute poisoning and tumors in animals.
In addition, individual flour producers may use industrial oxidizers and bleaches that are cheaper and whiten better but more toxic, such as hanging white block, calcium hypochlorite and phosphor, as well as fumigation with sulphur. Reasonable use of preservatives such as potassium sorbate and calcium propionate is conducive to prolonging the shelf life of products, but excessive use is harmful to human health. During the processing of fillings, individual enterprises use sodium peroxide to bleach lotus seeds, resulting in strong alkali residue in the fillings, which harms the human digestive tract.
Sugar is an important accessory to the production of baked goods, should choose white color, impurities less high-quality white sugar, individual manufacturers choose yellow sugar for cost considerations, easy to cause excessive heavy metals and fat in the finished product HaChang, in addition, this kind of sugar is also often sugar mites exist.

In recent years, there are reports of nut allergy, the most common is peanut allergy, some cases of allergic reaction is extremely serious, and even lead to death, so the goods containing nuts should be clearly marked on the label.
1.3 Physical Hazards
The raw materials used in the manufacture of baked goods mainly come from agricultural production systems, and these raw materials are often adulterated with foreign substances, such as metals, stones, sticks, twigs and leafy stems, glass fragments, etc., which cause physical hazards to the human body.
Hazard analysis of the production process

The production process of baked goods generally includes the reception of raw and auxiliary materials, ingredients, dough modulation, molding, baking, cooling, packaging and other processes, for moon cakes and other confectionery also includes the production of fillings and filling, and for some cakes, there are also laminating and decorating processes.

2.1 Receipt and storage of raw and auxiliary materials
As mentioned above, there are various potential hazards in raw and auxiliary materials, if the inspection is not strict when receiving, it is possible to bring the hazards in raw and auxiliary materials into the product, especially the chemical hazards, which are difficult to eliminate in the later processes.

Accepted raw and auxiliary materials should be stored under suitable conditions before use, otherwise they may cause the growth and multiplication of microorganisms, etc.

For example, great care should be taken to prevent contamination of flour during the very short storage period before use, which requires regular cleaning of all dead space in the flour system and frequent fumigation and disinfection with safe insecticides.
Any broken bags should be used up early, as leaking flour can easily lead to rodent and insect infestations. Flour storage areas should be cool, well-ventilated, and protected from rodents, birds, and insects. If the flour needs to be stored for a long time, the moisture content of the received flour should be about 13% or less.

Fats are best stored at low temperatures, protected from light, avoiding contact with metals, minimizing contact with air, and used up as soon as possible, especially when hot liquid oils are operated in bulk to prevent rancidity of the fat.

Edible nuts usually have a maximum moisture content of 6%, so it is important to store nuts under dry conditions to prevent mold growth. The fat content of nuts is high, and storage at low temperatures and removal of air can slow the rate of fatty acid rancidity.

2.2 Ingredients
In the processing of baked goods to use flavors, colors, preservatives, sweeteners and other food additives, their weighing should be accurate, the amount should be in line with the provisions of GB2760, especially those potentially hazardous to human health preservatives, colors and other additives, weighing is more important to be accurate, otherwise it will bring serious consequences to consumers.

2.3 Dough modulation
Improper operation in this process will cause the temperature to rise, on the one hand, affecting the formation of gluten, and on the other hand, creating favorable conditions for the growth of bacteria.

In the dough modulation process to add relaxing agents such as baking soda, they must be completely dissolved in water before feeding, such as the failure to dissolve all the particles in the billet state, the baking will cause its decomposition products localized concentration, resulting in the product into a bubble, the appearance of the internal cavity and the surface of the black spot, affecting the quality of the product.

Sulfites can reduce the gluten strength of the dough and improve the plasticity of the dough. However, sulfite will generate sulfur dioxide during processing, which is hazardous to human health, so its added amount must comply with the regulations.

2.4 Dough fermentation
For products such as bread, there is a process of dough fermentation. If the fermentation temperature is too high, it will cause the growth of acid-producing bacteria, so that the acidity of the dough increases and the quality of the product decreases. Improperly designed equipment may facilitate the proliferation of harmful microorganisms such as bacillus and enterobacteria, thus reducing the acceptability of the product.
2.5 Molding
This process in some large-scale enterprises have been replaced by mechanical manual operation, but more small and medium-sized enterprises are still using manual operation, if you do not pay attention to personal hygiene and timely disinfection of table utensils is easy to cause cross-contamination.

Molding operation if the time is too long, molding equipment is not clean, easy to cause microbial growth and reproduction. For moon cakes and other products, the raw materials for making fillings should be fresh, moldy plants such as olives, peanuts, etc. should be eliminated, animal meats should be cooked, and fillings made of various raw materials should be used as soon as possible, otherwise, the resulting hazards are difficult to be completely eliminated in the later processes.
2.6 Baking
Baking on the one hand makes the product mature, on the other hand, kills the microorganisms existing in the raw billet to ensure the safety of the product. Therefore, the temperature and time of baking should be strictly controlled. If the heating is not sufficient (e.g. at the end of baking, the batter in the center of the cake is found to be not yet solidified), the product is prone to spoilage caused by filamentous mucoid bacteria.

Filamentous slime molds, represented by the potato bacillus, are often found in soil and grains, and their spores can withstand temperatures as high as 140°C. The spores can also withstand temperatures as high as 140°C. The center temperature of bread and cake at the end of baking is about 100℃, and the local temperature is less than 100℃ when the baking is not thorough, so it is impossible to kill all the spores of filamentous mucoid bacteria.

In the summer and fall high temperature season, the spores will quickly grow into a fungus, by decomposing starch and protein to form mucus, and produce a special odor and taste. However, the heating temperature should not be too high, otherwise unfavorable chemical reactions will occur, generating harmful substances such as benzo(a)pyrene and heterocyclic amines.

If the grease is not managed properly, it will make the baking mold and cooling stand with bad smell, which will affect the quality of the product. Due to the application of grease for a long time at high temperatures, and directly with the metal baking pan (or baking mold) in contact with iron ions, very easy to oxidation rancidity.

2.7 Cooling
Just out of the product temperature is very high, in the cooling process will continue to evaporate water, such as premature packaging, the evaporated water will accumulate in the inner surface of the packaging material, to the microbial reproduction provides the humidity conditions, the finished product will be easy to moldy and deteriorate.

In the peak season, some factories tend to pack the products before they are sufficiently cooled, which is easy to make the products moldy. The sanitary environment during cooling should be clean, the number of microorganisms in the air should be small, and the cooling time should not be too long, otherwise it will cause secondary contamination of microorganisms.
2.8 Packaging
Packaging boxes or bags do not meet the relevant health standards, easy to cause chemical pollution. Workers engaged in the internal packaging of poor personal hygiene, packaging room sanitation facilities are not complete, packaging materials are unclean can bring the secondary pollution of microorganisms. External control of mold inhibitor contact products can cause chemical pollution, packaging sealing is not tight can make the air microbes into the bag caused by re-contamination, at the same time, the external control of mold inhibitor will lose effectiveness.
2.9 Storage
High or fluctuating temperatures during storage can lead to problems such as oil loss, refrosting, chocolate spoilage and rancidity. High humidity reduces the strength of the cardboard box and increases the rate of moisture transfer across the packaging film, so products such as cookies should be kept dry and cool when stored. If necessary, the use of well-insulated walls and ceilings, together with gas conditioning and air circulation, will reduce localized high temperatures or temperature fluctuations.
Critical Control Points and Control Measures in the Production of Bakery Products

3.1 Acceptance of raw materials
Pathogenic bacteria such as Listeria monocytogenes and Salmonella monocytogenes may be present in milk and eggs in raw and auxiliary materials, and aflatoxin may be contaminated in flour and fat. Pathogenic bacteria cannot be guaranteed to be all killed in the later baking process, and aflatoxin is difficult to be completely eliminated in the later processing, so biological hazards are identified as the critical control points.

Pesticide residues in flour, heavy metals, flour whiteners, pesticide residues in oils and fats, acid value and peroxide value, veterinary drug residues in milk, eggs and other raw materials, these chemical hazards can not be eliminated in the later processing, and therefore, are also critical control points.

Of course, whether the packaging materials comply with food hygiene standards is also a key control point.

Physical impurities in raw materials are generally not considered as critical control points. However, for products packed with fillings, if the filling raw materials (e.g. mung beans) are mixed with sand and metal fragments, they should be cleaned and screened to remove sand and metal during raw material processing, especially sand and stone, which are difficult to be removed in the later process, and therefore should be identified as a critical control point.
Control measures: select qualified suppliers and regular evaluation of suppliers, for raw and auxiliary materials and packaging materials entering the factory into the warehouse, the quality inspection department should carry out strict inspection of its main quality indicators, pesticide residues in raw materials and auxiliary materials, veterinary drug residues, heavy metals and other harmful substances in the regular testing, non-compliance with the provisions of the refusal to enter the warehouse and use.

Storage of raw and auxiliary materials is also very important to control the growth and reproduction of microorganisms and oxidative rancidity of fats and oils, etc., therefore, we should control the temperature, humidity and sanitary conditions of the storage, which can be controlled through the implementation of GMP and SSOP, so it is not as a key control point.
3.2 Ingredients
For some products that need to add preservatives, antioxidants, synthetic colors and other additives, if the ingredients are not weighed properly, it may lead to additives exceeding the standard, which is harmful to human health, so it is determined as a critical control point.

Control measures: First, strictly in accordance with the process requirements for the ingredients, and 2 people review system; Second, regular calibration of the relevant measuring instruments to ensure the accuracy of the instruments.

3.3 Baking
In the processes of dough modulation and molding, attention should be paid to the hygienic cleanliness of the operating environment and the hygienic safety of the equipment, which can be controlled by the SSOP, so these processes are not regarded as critical control points. Nevertheless, the number of microorganisms in the dough will continue to increase, so it is important to minimize the duration of the operation and control the temperature and hygiene of the operating environment.

Baking is the only process that can kill microorganisms during the processing of baked goods, and its success or failure is related to the number of microorganisms in the finished product. If the baking temperature is not properly controlled or the baking time is incorrect, it will cause insufficient sterilization and lead to the subsequent over-propagation of microorganisms, which will bring about serious food safety hazards, so the baking is identified as the key control point.
Control measures: the baking process should be reasonably designed to ensure that the heating intensity can kill a sufficient number of microorganisms. At the same time, the baking temperature and baking time should be accurately controlled, which requires frequent checking of the performance of the oven, observing whether the temperature displayed by the oven meets the baking requirements and whether the timer is accurate.

The baking process should pay special attention to the baking temperature is too high when the phenomenon of scorched inside, baking temperature and time is best to use automatic control, to reduce the quality problems caused by human factors.

3.4 Cooling
Just out of the product temperature is high, it must be sufficiently cooled before packaging, otherwise it will lead to mold, soft skin and other problems caused by dew and moisture after packaging, but also exacerbate the oxidative rancidity of oil.
However, microorganisms begin to grow and multiply again when the product is cooled to below 60℃. Too long cooling time or too humid air in the cooling room can easily cause re-contamination of products such as bread and cakes. Therefore, cooling can be identified as a critical control point.

There are also some enterprises that do not take cooling as a critical control point, but take natural cooling, and the environmental hygiene of cooling is controlled by SSOP. Moreover, for cookies, the ambient temperature and humidity during cooling should not be too low, and the cooling speed should not be too fast, or else it will easily cause product rupture. Therefore, whether to take cooling as a critical control point should be decided according to different product characteristics, process routes and production conditions.
Control measures: Bread and cake after baking should be cooled by accelerated cooling under air circulation conditions, and the temperature of bread and cake should be cooled to below 35℃ within a short period of time. The cooling room should be equipped with exhaust fan or other dehumidifying device to remove the water evaporated from the surface of bread and cake in time.

3.5 Mounting and decorating
The number of microorganisms in the cake will continue to increase during the laminating and decorating process, so the temperature in the laminating room should be low and the laminating time should be short in order to prevent a large number of microorganisms from multiplying.

3.6 Packaging and metal detection
If the packaging material is not hygienic and the sealing is not tight, it is easy to cause secondary contamination of microorganisms. Products such as cookies are prone to moisture absorption, so packaging can be included as a critical control point for certain bakery products.

Some companies put the packaging procedure in the operational prerequisite program for control. For certain confectionery products, the raw materials may be mixed with impurities such as metal fragments, glass or stones, and the products may also bring in metal fragments when the processing equipment malfunctions, and these impurities can cause physical harm to the human body, so the products should be inspected by a metal detector after packaging, and are therefore identified as a critical control point.

Control measures: Regularly check the sealing temperature and speed of the sealing machine, and check the sealing tightness. For metal fragments and other impurities, the finished product can be metal detection and X-ray detection and other methods, and at the same time, the sensitivity of the metal detector should be checked regularly.