نشریه بهداشت مواد غذایی
سال سیزدهم شماره 1 (پیاپی 49، بهار 1402)

Food products spoil very quickly due to microbial, chemical, and enzymatic reactions that are the main cause of rapid quality deterioration. Nowadays, there is increasing consumer demand for high-quality foods with natural preservatives such as microalgae extracts. Microalgae are potential alternatives to reduce microbial growth, increase oxidative stability, and protect the sensory characteristics of foods. Researchers showed that the use of microalgae extracts in the diet of aquatic animals can increase meat quality and production. In this review article, the direct application of various microalgae extracts as seafood preservatives and their functional properties in seafood, such as: (antioxidant and antimicrobial activities) are investigated. In addition, the potential application of microalgae extracts in the composition of foods and their effect on the quality of foods are also presented. The result of reviewing many articles showed that despite the many advantages of microalgae, there are still many challenges in the production and use of microalgae biomass or its derivatives in the food industry, hence the safety assessment and the use of ideal concentrations for studies. Future studies are still necessary to determine the optimal concentration for the large-scale use of microalgae extracts in industry and seafood, to develop effective strategies or to prevent the occurrence of food product spoilage, as well as to increase the welfare of consumers.

Some zoonotic parasites such as Hydatid cyst, Fasciola species and Dicrocelium dendriticum cause death and economic losses in ruminants. The aim of this study was to investigate the prevalence rate of liver parasites in sheep and goats slaughtered in Saveh slaughterhouse and to estimate the economic losses caused by their condemnation. In a retrospective study, from April 2014 to April 2020, a total of 58,699 animals including 13,044 goats and 45,655 sheep were inspected in Saveh slaughterhouse for liver contamination with Hydatid cyst, Fasciola species and Dicrocelium dendriticum. The results showed that 72.85% of the animals were infected with parasites, 41.18%, 28.08%, and, 3.58% were infected with Dicrocelium dendriticum, Hydatid cyst, and Fasciola species, respectively. There was a statistically significant. The rate of infection with Dicrocelium dendriticum, Hydatid cyst and Fasciola species was 21.70%, 17.44%, and 1.33% in sheep and 16.48%, 10.64%, and 2.25% in goats, respectively. Statistically, the prevalence rate of liver infection with seasons was not significant except for 2015. The economic losses caused by the condemnation of the liver of slaughtered sheep and goats were estimated at 23,324,560,000 Rials ($241,330.16). With the high prevalence of parasitic diseases in small ruminants in the region and the economic losses caused by the condemnation of infected livers, and due to the fact that these diseases are zoonotic, it is crucial to use appropriate management methods to prevent or control the disease by competent authorities.

Biosurfactants are amphipathic compounds that are produced by many microorganisms and show a wide range of biological activities due to their unique characteristics. This study aimed to determine the antioxidant and antimicrobial potential of the biosurfactants isolated from Lactobacillus plantarum, Lactobacillus pentosus, and Lactobacillus casei. The antioxidant activity of biosurfactant was evaluated in vitro conditions using the ability to inhibit 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl free radicals and antimicrobial activities using the diffusion method in agar wells against pathogenic bacteria. The results showed that the inhibitory activity of DPPH and hydroxyl of biosurfactants at a concentration of 5 mg/ml was 78.51-81.99% and 69.51-71.56%, respectively, and the highest antioxidant activity was related to Lactobacillus plantarum (P<0.05). The results of inhibiting microbial growth showed that all biosurfactants had high antimicrobial activity and the antimicrobial activity against Staphylococcus aureus (gram-positive) was higher than other bacteria (gram-negative). No significant difference was observed among different biosurfactants. It seems that biosurfactants obtained from lactobacilli can be used as natural antioxidants and antimicrobials in the food and pharmaceutical industries.

Among the environmental pollutants, heavy metals are very dangerous for human health.  The present study aimed to determine the amount of lead and cadmium in the fall of 2017 and spring of 2018 kinds of honey in Lorestan. Sixty honey samples were collected randomly from the central, Kakavand and Kaveh areas of Delfan city of Lorestan. The samples were analyzed by flame atomic absorption spectrometry. Lead and cadmium were determined in all samples. The maximum levels of lead and cadmium in samples were 32.2 and 0.32 µg/kg respectively.  The mean concentration of lead in spring and autumn honey in the central part was 21.57 ± 2.84 and 28.83 ± 2.47, in Kakavand was 10.8 ± 1.3 and 13.66 ± 1.89 and in Khaveh was 7.72 ± 1.76 and 16.44 ± 1.55 µg/kg respectively. In Khaveh, the amount of lead in the honey sampled during spring was significantly lower than in other areas (p<0.05).  The mean concentration of cadmium in spring and autumn honey in the central part was 0.13 ± 0.02 and 0.26 ± 0.03, in Kakavand was 0.11 ± 0.014 and 0.18 ± 0.02 and in Khaveh was 0.04 ± 0.02 and 0.08 ± 0.01 µg/kg respectively. The amount of cadmium in the spring honey of Khaveh was significantly lower than in other areas (p<0.05). Due to lower levels of lead and cadmium in the spring and autumn samples produced in Delfan city, compared to international standards, it could be concluded that consumption of these honey is safe, in terms of lead and cadmium metals.

The excessive use of antibiotics in animal husbandry has led to the appearance of antibiotic residues in meat and could threaten public health. The study aimed to determine the oxytetracycline residue level in meat products in Tabriz. A total of 60 samples of meat products (sausages, Persian sausages and hamburgers, 20 samples from each meat product) were randomly collected from food supply stores in Tabriz from March to May 2021. High-performance liquid chromatography was used to determine the level of oxytetracycline residue levels in the samples. The results showed that the mean of oxytetracycline residue in sausage, Persian sausage, and hamburger was 82.48±7.06, 57.35±4.27, and 150.79±3.65 µg/Kg, respectively. The mean value of oxytetracycline residues showed a significant (p<0.05) difference between the three products. Also, oxytetracycline residue was observed in all samples. However, in all samples, it was below the allowed limit of Codex Alimentarius (200 µg/kg). The average residue of oxytetracycline in hamburgers was significantly higher than in sausages. In hamburgers with 90% meat, the average amount of oxytetracycline was more than in hamburgers with 70% meat, which can be related to the percentage of meat in the product (p<0.05). Although the level of oxytetracycline residue in the present study was less than the permissible limit, considering the consumption of meat products in the country, it is necessary to control and monitor the presence of antibiotics in foods of animal origin.

Shrimp is one of the most popular sources of marine protein worldwide. Due to its high nutritional and economic value, this aquatic product is a major export product in many countries. The shrimp industry includes a significant percentage of all aquaculture products. Contamination of shrimp with pathogenic microorganisms can endanger the health of the consumers. In this regard, the aim of this study is to determine the microbial and chemical characteristics of shrimps supplied in Abadan city. A total of 100 shrimp samples were taken from Abadan city in a simple random manner and transferred to the specialized food hygiene laboratory of Islamic Azad University, Shahrekord branch, in an ice flask and under sterile conditions and microbial tests included Staphylococcus aureus, Escherichia coli, and Salmonella as well as total count and TVN test were performed on the shrimp samples. The results showed that the contamination rate with S. aureus, Salmonella, and E. coli was 14%, 7%, and 2%, respectively. The total count, TVN, and coliform contamination were within the acceptable range. Due to the high importance of E. coli and Salmonella pathogenic microorganisms, it is necessary to monitor closely and as many regulatory institutions as possible to reduce the pollution load.