Packaging, which includes creating a suitable cover, especially in terms of durability, for all products in the market, is very important as one of the main things before the release of any product. Product packaging may not seem like a difficult task, but if we pay attention to the importance of preserving and preserving the health of packaging products, we will realize the true value of this important industry. One of these products whose packaging is very sensitive is meat and meat products.
Meat and meat products may be easily infected with various microorganisms, and if their transportation conditions are not suitable, it leads to the growth of spoilage and pathogenic bacteria, and ultimately the quality of meat is reduced and public health is at risk. take Cold storage is considered the most common method of preserving meat and meat products. In some countries, in order to increase the shelf life of meat and meat products, antimicrobial and antioxidant substances, which are mostly synthetic, are used. Today, with the increasing demand of food consumers to minimize processing, the emergence of ready-to-eat food products, the global nature of food trade, and the basic challenges for food processing with high quality and safety, new methods are needed to prevent corruption in Food items came up. One of these new methods is active or antimicrobial packaging. This packaging technology plays an important role in increasing the life of food and reducing the risk of pathogens. Active substances react biologically with the product or the upper space between the packaging and food systems, so that depending on the type of active substances, either antioxidant or antimicrobial, results are obtained in delaying or inhibiting oxidation or inhibiting pathogenic compounds.
Meat contains large amounts of compounds that are necessary for the growth and reproduction of bacteria, yeasts and molds. Therefore, meat is one of the most perishable foods. Fresh meats such as beef and mutton, fresh poultry and marine animals and meat products have a suitable pH so that microorganisms can grow well in it. In addition to proper pH, sufficient nutrients and moisture also prepare the environment for the growth and development of microbes. The pH in the surface areas of the meat pieces is high so that all kinds of aerobic and facultative anaerobic bacteria can grow there, also due to the low pH inside the meat tissue, most of the absolute anaerobic bacteria are able to work in these areas. An animal that has rested enough before slaughter, its meat undergoes a series of gradual changes after slaughter, which finally leads to the production of meat, during which (24-36 hours after slaughter) and the normal temperature of the carcass, microbes which leave the lymph nodes of the carcass, form part of the natural flora of the meat. Also, the microorganisms that enter the meat through the slaughtering equipment, animal skin, intestinal waste, dust, workers’ hands, carcass cutting knives and the place of storage, together form another measure of floromicrobia. These microbes will be able to cause spoilage of meat in the long term, even at refrigerator temperature. When the meat or carcass is placed in a refrigerator, the temperature of its surface parts decreases, but such a phenomenon does not occur in the deep parts. Therefore, there is a possibility of spoilage of meat by microorganisms in these areas. One of the most important of these microbes is Clostridium perfringenes and various species of the Enterobacteriaceae family, and on the other hand, bacterial spoilage of meat in the refrigerator is, in most cases, a surface phenomenon that results from the activity of microbes that entered the meat from outside. If the humidity of the refrigerator is high, fresh meats will suffer from bacterial spoilage rather than mold, and the most important characteristic of this type of spoilage is the formation of slime on the surface of the product. But when the surface moisture of the meat is not enough for the growth of bacteria or when the meat contains antibiotics such as tetracycline, molds will be the cause of spoilage.
Oxidation of fats and microbial contamination are two very important factors that play an effective role in the quality and shelf life of meat and meat products. Therefore, delaying the phenomenon of oxidation and preventing microbial contamination is one of the main goals of food producers in the meat and meat products industry. Although artificial additives and antioxidants are currently widely used in the meat industry, but the tendency towards the use of natural antioxidants is due to the lack of acceptance shown by food consumers for the consumption of these synthetic substances, as well as the problems that this Antioxidants have increased in terms of safety and toxicity. One of the main disadvantages of chemical preservatives is their carcinogenicity, which has been proven in laboratory animals. Therefore, it is felt necessary to use biological compounds that have no side effects and on the other hand have antimicrobial and antioxidant properties.
Spirulina algae is a filamentous and spiral blue-green cyanobacterium that is widely used in the enrichment of human and animal food today. Spirulina has a large amount of high quality protein, including essential amino acids with high digestibility, pigments such as
carotenoids and phycocyanin, vitamins and minerals such as calcium and iron. Spirulina is one of the blue-green filamentous multicellular microalgae approved by the Food and Drug Administration. The value of spirulina is due to its easy digestion due to the lack of cellulose in the cell wall and its nucleic acid content is less than five percent. Spirulina has all the essential amino acids and has a high biological value.
Spirulina is not only a complete food, but as a food supplement it can be used to prevent or treat nutritional deficiencies. The nutritional compounds of this algae are superior to animals in terms of chlorophyll and protein in many parameters. This algae is used as a food supplement in many countries such as Japan and America, due to the antioxidant and antimicrobial properties of spirulina algae, this capacity exists in it. To be used as an edible coating for the purpose of preserving food products.
Especially in recent years, extensive research has been done on the use of edible coatings in food packaging. Nowadays, the use of food coatings has increased due to the desire of customers to buy products that preserve their freshness. In the meantime, an edible coating based on different percentages of 70% hydroalcoholic extract powder of algae in concentrations of 0.5 to 1.5% spirulina along with fixed percentages of gelatin powder (2%), chitosan powder (1%) and glycerol (1%) ) based on previous experiments, it was used as a lubricant on veal meat. The results of the physicochemical tests showed an increase in moisture, acidity and total phenol with an increase in the amount of Spirulina platensis in different coating samples. The colorimetric results also showed that the transparency of the base samples decreased with the increase in the percentage of spirulina. The results of the nutritional evaluation showed that the amount of protein, iron and ascorbic acid increased significantly by increasing the amount of Spirulina platensis. Also, increasing the amount of Spirulina platensis was effective in the taste and color of the samples, which can be detected by sensory evaluations. The results indicate that the effect of increasing Spirulina platensis has a significant effect on reducing microbial growth. Because spirulina contains basic bioactive compounds with anti-corruption and antioxidant activities, which include phenolic compounds, phycobili protein and phycocyanin. C-phycocyanin in spirulina has been reported to have antioxidant and anti-inflammatory properties. The antioxidant properties of phycocyanin have been attributed to radical scavenging and metal chelating activity. Flavonoids, beta-carotene, vitamin A, and alpha-copherol present in spirulina largely participate in the high antioxidant activity of this algae.
Another research was conducted regarding the effect of spirulina algae extract on the shelf life of meat. In this research, algae extract was extracted and sprayed on meat. The purpose of this work was to investigate the possibility of increasing the shelf life of meat by adding a thin layer of spirulina algae extract on the meat. Gelatin was used to increase the consistency of the extract. The amount used was determined after measuring the properties and antibacterial and antioxidant properties of this substance. The meat was beef that was minced after preparation. After adding the extract, the meat was placed in a refrigerator at +4 degrees Celsius and a freezer at -18 degrees Celsius, and meat spoilage was examined in a period of 21 days until complete spoilage in the freezer until complete spoilage in a 90-day period. . Examining the results of the presence of a halo inhibiting the growth of bacteria due to the use of spirulina extract. This study showed that spirulina algae extract has antibacterial properties that can prevent the growth of bacteria in the environment. These results showed that spirulina, apart from having no effect on Listeria monocytogenes bacteria, which does not create any growth inhibiting halo, is able to create a halo of growth inhibition in all other bacteria, which in most cases is very effective compared to antibiotic treatments and even to Individual form is better than a number of antibiotics with a significant effect (p<0.05).
Unfortunately, the use of different compounds to make a biofilm that protects against the penetration of bacteria and increases the shelf life of food does not have much history. But in the last 15 years, significant progress has been made in the field of packaging with the aim of improving the physical, chemical, microbial and organoleptic properties of meat and seafood products. In conventional or passive packaging, which is done using a series of plastic and cellulose compounds, the main goal is to provide an impermeable layer on the product. While in the other type, which is called active packaging, in order to improve the properties of the coating and increase the shelf life of the food, a series of chemical and physical compounds are used in the packaging coating. Currently, although the latter type of packaging is not yet available in a completely commercial form, but according to most experts, in the next few years this type of packaging will completely replace the usual packaging.
According to the research done, it can be said that adding spirulina algae extract to meat and sea foods due to its antioxidant and antibacterial properties improves biochemical and microbial parameters during 21 days of storage in the refrigerator at 4 degrees Celsius and 90 days of storage in The temperature of the freezer was 18-degree Celsius, so that the process of chemical and microbial spoilage in the meat covered with spirulina was significantly reduced compared to the control group.
The result is that according to the demand of consumers for access to high quality food and their concern due to the problems caused by the consumption of synthetic preservatives and also the environmental concerns caused by the accumulation of synthetic polymers, the technology of using spirulina algae and its extract in order to create Biodegradable coatings with high antioxidant and antibacterial properties can be a suitable alternative.
Those interested in the production and cultivation of spirulina algae can contact the Pars algae dream team and visit the spirulina algae production line if they wish.
