JOURNAL OF NUTRITION, FASTING AND HEALTH
Year:2019 | Volume:7 | Issue:4|Papers Count:8

Introduction: Olivier salad is a commonly used cold fast food in Iran, which contains various nutrients. However, this food product is susceptible to bacterial contamination. The present study aimed to evaluate the chemical and microbial quality of the ready-to-eat Olivier salads sold in the groceries in Mashhad, Iran. Methods: This study was conducted on 26 samples of two types of Olivier salad containing chicken (n=17) and meat (n=9), which were collected from the local markets in Mashhad city. The samples were transferred to the laboratory in cold flasks to evaluate their microbial quality (coliforms, Escherichia coli, Staphylococcus aureus, Salmonella spp., clostridium perfringens, molds, and yeasts) and chemical quality (potassium sorbate, potassium benzoate, and benzoate levels) based on the Iran national standard No. 17813 and 17813-a-1, respectively. Results: Chemical tests indicated no significant differences in the levels of potassium sorbate, potassium benzoate, and benzoate (P>0. 05) between the samples. On the other hand, 7. 7% (2/26) and 23. 07% (6/26) of the Olivier salad samples were contaminated with Salmonella and Escherichia coli, respectively, while all the samples were negative for Staphylococcus aureus contamination. Conclusion: Salmonella and Staphylococcus aureus are of particular importance in food contamination. Lack of hygiene during production, contamination of raw materials, and elevated storage temperature are among the key influential factors in the increased contamination of food products. Therefore, the control and monitoring of the food chain must be prioritized.

Introduction: The present study aimed to assess the effect of Arctium lappa extract inoculated with Lactobacillus plantarum probiotic bacteria on fermented salted cabbage. In addition, the microbial, chemical, and sensory properties and survival experiment of the bacteria were evaluated during storage. Methods: Lactobacillus plantarum was used as a probiotic species in fermented cabbage. The effects of various levels of salt (1% and 1. 5%) and Burdock extract (2 and 4 mg/ml) were evaluated and compared with control samples (without the dandruff extract) with the inoculation of Lactobacillus plantarum probiotic bacteria as the starter. Results: Increased concentration of the Arctium lappa extract and minimum concentration of salts led to the significant reduction of yeasts and aerobic mesophyll (1. 5% salt and 4 mg/ml of the herbal extract). On the other hand, decreased concentration of salt and increased concentration of the Arctium lappa extract led to the increased viability of Lactobacillus, and the maximum survival of Lactobacillus plantarum was observed in the treatment with 1% salt and 4 mg/ml of the extract on day 21. Conclusion: According to the results, using Lactobacillus plantarum as the starter, along with salt and the Arctium lappa extract, could improve the microbial control of the fermentation process, while increasing the production of lactic acid and improving the acidity of the saline of salty cabbage.

Introduction: Recently, there has been growing demand for the fabrication of edible antimicrobial and antioxidant compounds for the monitoring of foodborne bacterial diseases, which are mainly responsible for the contamination of raw foodstuffs. The present study aimed to use polyvinylpyrrolidone (PVP) enriched with garlic extract to control Listeria monocytogenes (LM) and Staphylococcus aureus (SA) in fresh sheep meat at over-chilled temperature for one week. Methods: The obtained minced meat were divided into 100-gram portions, inoculated with SA and LM (7 log CFU/g), aseptically packed in designated PVP containing garlic extract (0%, 0. 25%, and 0. 5%), and transferred to a sterile polyethylene bag. All the samples were stored at refrigerated temperature for one week. Results: PVP enriched with garlic extract at the concentrations of 0. 25% and 0. 5% could decrease the LM and SA counts to 2. 30-2. 82 and 2. 51-1. 36 log CFU/g, respectively (P<0. 05). Conclusion: According to the results, PVP containing garlic extract at the concentrations of 0. 25% and 0. 5% exerted inhibitory effects against LM and SA in raw sheep meat.

Introduction: Consumption of proper amounts of probiotic microorganisms through food products has several health benefits for the host. Recently, growing research has been focused on the characterization and verification of the potential use of probiotic films in food industry. The present study aimed to investigate the in-vitro antimicrobial properties of probiotic carboxymethyl cellulose-sodium caseinate (CMC-SC) films containing Lactobacillus acidophilus, L. reuteri, and Bifidobacterium bifidum against Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli O157: H7. Methods: CMC-SC composite films were prepared using the casting method. The in-vitro antibacterial properties of the CMC-SC films were evaluated using the agar disk diffusion and broth microdilution methods. Results: The antimicrobial properties of the probiotic films were as follows (inhibition zone diameter and log differences in the population, respectively): S. aureus (2. 13-5. 65 mm,-0. 79--3. 82)>L. monocytogenes (1. 76-5. 32 mm,-0. 65--3. 34)>S. typhimurium (2. 13-4. 33 mm,-0. 34--2. 79)>E. coli O157: H7 (1. 88-3. 86 mm,-0. 18--2. 62). The optimal antimicrobial effects against the mentioned bacterial pathogens were observed in the films supplemented with L. acidophilus + L. reuteri + B. bifidum. Conclusion: According to the results, incorporation of some probiotic strains into edible films could result in remarkable antimicrobial effects against S. aureus, L. monocytogenes, S. typhimurium, and E. coli O157: H7, which is an effective solution to the issue of safety in the food industry.

Introduction: Various species of Pseudomonas are abundantly found in the environment. Although they are weak pathogens, these bacteria play a key role in food hygiene and human health as they are psychrotrophic bacteria and could grow and proliferate at refrigerated temperatures, producing proteolytic and lipolytic enzymes. The present study aimed to evaluate the effects of microwave radiation, organic acid, and salt combination on the survival of Pseudomonas aeruginosa inoculated in veal meat in refrigerated storage. Methods: The simultaneous effects of various doses of microwave radiation and various concentrations of salt and lactic acid on P. aeruginosa inoculated onto veal meat were assessed. In total, 108 samples were evaluated in nine treatments on days zero, three, six, nine, 12, and 15 during chilled storage at the temperature of-4⁰ C. The control group was treated with distilled water. The bacterial count was determined in Pseudomonas Agar medium, which indicated that various concentrations of acid and salt, as well as different microwave exposure times and their interactions, had significant effects on the mean logarithm number of bacteria during the refrigeration period. Data analysis was performed in SPSS version 21 using the mixed repeated measures ANOVA. Results: The interactions between microwave radiation, organic acid, and salt caused further reduction in the bacteria count compared to the control group. A significant difference was observed in the bacterial count in the acid and salt treatments with the control group (P<0. 001). The effects of the salt concentration and microwave duration were controlled using 2. 5% and 5% lactic acid, which reduce the bacterial logarithm during the refrigeration period compared to the acid-free samples (P<0. 001). In addition, 5% acid significantly decreased the bacterial count logarithm during the refrigeration period compared to the samples treated with 2. 5% acid (P<0. 001). By controlling the effects of acid concentration and microwave duration, use of 4% and 6% salt significantly decreased the bacterial count logarithm during the refrigeration period compared to the non-salt samples (P<0. 001). On the other hand, the samples containing 6% and 4% salt had no significant difference in terms of the bacterial count logarithm during the refrigeration period (P=0. 89). The microwave duration of nine seconds (65° C) could significantly decrease the bacterial logarithm compared to seven (55° C), five (45° C), and three seconds (30° C) (P<0. 001). Moreover, use of lactic acid (5%) and salt (6%) caused the microwave duration to reduce from nine seconds (65° C) to five seconds (45° C) to complete the elimination of bacteria. Conclusion: According to the results, use of organic acid, salt, and microwave irradiation for P. aeruginosa inoculated into meat during refrigerated storage reduced the bacterial count. Furthermore, the combination of microwave radiation, organic acid, and salt concentration decreased the bacterial count more significantly compared to the control group, and a significant difference was observed between the bacterial counts when each factor was used compared to the control group.

Introduction: Intelligent packaging could be used to control the environment of food products and inform consumers of food conditions. The present study aimed to design a simple pH-sensitive label in chicken package to demonstrate food spoilage by color change. Bromocresol green (BCG) is a pH-sensitive color indicator, which was used to detect chicken spoilage and attached to the inner side of the package. Chemical (pH and total volatile base nitrogen [TVBN]), microbial, and sensory analyses were performed at the intervals of zero, three, five, seven, eight, and 10 days of storage at the temperature of 4° C. Methods: On the first day, the TVB-N was 19 mg/100g, while it was measured to be 29 mg/100 g on day eight and 46 mg/100g on the last daIntelligent packaging could be used to control the environment of food products and inform consumers of food conditions. The present study aimed to design a simple pH-sensitive label in chicken package to demonstrate food spoilage by color change. Results: Bromocresol green (BCG) is a pH-sensitive color indicator, which was used to detect chicken spoilage and attached to the inner side of the package. Chemical (pH and total volatile base nitrogen [TVBN]), microbial, and sensory analyses were performed at the intervals of zero, three, five, seven, eight, and 10 days of storage at the temperature of 4° C. On the first day, the TVB-N was 19 mg/100g, while it was measured to be 29 mg/100 g on day eight and 46 mg/100g on the last dayy. According to the obtained results, the changes in the BCG color due to chicken spoilage were detectable by the naked eye, and the bacterial count was estimated at 6. 62 Log10CFU/g. On day 10, the color of the indicator turned blue, and the total bacterial count reached approximately7. 20 Log10CFU/g. In addition, significant correlations were observed between the TVBN, pH, and microbial and sensory analyses in the studied samples with the changes in the color of the indicator during storage. Conclusion: Due to the increased TVBN during storage, the color of the BCG indicator changed from yellow to blue. Therefore, the BCG indicator could be employed as an inexpensive, simple label to show the freshness of chicken meat.

Introduction: Due to the development of dairy industries, the consumption of Doogh has risen in Iran as a functional fermented beverage. Use of preservatives to reduce microbial contamination in Doogh could increase the risk of chronic diseases in the long run. The present study aimed to extensively investigate the effects of natamycin as a preservative on the microbial population of Iranian Doogh at various storage temperatures. Methods: Microbial analyses were performed to determine the total count of microorganisms, population of fungi (molds and yeasts), coliforms, Escherichia coli, coagulase-positive staphylococci, and lactic acid bacteria in Doogh samples. Results: The microbial population in the Doogh samples (with and without natamycin treatment) stored at 4° C was compared to the samples stored at 25° C and 35° C during the shelf life period. At the temperature of 25° C, natamycin could significantly control the growth of a wide range of microorganisms (P<0. 05), while at 35° C, in the presence of natamycin, the microbial contaminants in the majority of cases were significantly increased (P<0. 05). Conclusion: According to the findings, it can be concluded that paying attention to the microbial quality of raw milk, heat treatment, and cooling systems during transportation, environmental hygienic conditions and storage of the final products at refrigerated temperatures in order to effectively diminish the microbial population of Doogh and preventing spoilage is necessary.

Introduction: Receiving adequate vitamin D and calcium is essential to bone health and reducing the risk of osteopenia and osteoporosis. The present study aimed to co-encapsulate vitamin D and calcium using the ultrasonic emulsification technique and assess the physicochemical properties of the obtained emulsions and capsules. Methods: Two types of calcium salts and vitamin D3 were used as the core materials in modified starch microcapsules. The effects of the sonication process and formulation on the physicochemical properties of the emulsions and dried powder of the final spray were investigated. Results: Use of ultrasound homogenization with 80% maximum power for three minutes provided the optimum process conditions to fabricate the emulsions. In total, 16 emulsion formulations were prepared, and their physicochemical properties were evaluated. All the emulsions had narrow size distribution with more than 79% encapsulation efficiency. Based on the particle size and encapsulation efficiency, two formulations were selected and further characterized. Calcium carbonate and stearate containing the microcapsules had more than 89% encapsulation efficiency with the particle size of 2 and 2. 5 micrometers, respectively. In addition, 70% of vitamin D was preserved in the encapsulated form during eight month. Conclusion: According to the results, the co-encapsulated microcapsules of vitamin D3 and calcium could be used to prolong the stability and improve the solubility of vitamin D3 for food applications.