Journal of Food Quality and Hazards Control

42-43

Authors: N. Gautam, N. Sharma

This article has no abstract

45-52

Authors: N. Francesca, R. Guarcello, V. Craparo, G. Moschetti, L. Settanni, R. Gaglio

Background: Ready-To-Eat (RTE) foods include any edible food that is commonly consumed raw. This study aimed at evaluation of microbial ecology of retail RTE escarole and red chicory sold in Palermo city, Italy. Methods: A total of 32 mono-varietal RTE samples, including escarole (n=16) and red chicory (n=16) samples were obtained from Palermo, Italy. Both RTE vegetables at expiry date were analyzed to quantify spoilage bacteria, pathogenic bacteria, and yeast. All different colonies were isolated and identified on the basis of phenotypic characteristics and genetic polymorphisms by random amplification of polymorphic DNA-Polymerase Chain Reaction (PCR) and further genotype by sequencing the 16S rRNA gene. The statistical analysis was conducted with SAS 9.2 software (Statistical Analysis System Institute Inc., Cary, NC, USA). Results: The level of Listeria monocytogenes and coagulase-positive staphylococci were below the detection. Total microbial counts were above 8 log10 colony forming unit/g in RTE red chicory, while they were about 1 log cycle lower in escarole. In general, escarole showed lower levels for all microbial groups than red chicory with the exception of the total yeast. A total of 13 strains were identified into ten species belonging to six genera as Bacillus, Erwinia, Pantoea, Pseudomonas, Microbacterium, and Rahnella. The most numerous identified genera were Pseudomonas and Pantoea. Conclusion: This work pointed out the relevance of implementing good hygiene practices during processing in order to prolong quality parameters and acceptability of mono-varietal salads.

58-65

Authors: M. Mirzaie, S.S. Saei-Dehkordi, D.B. Levin

Background: In food industry, carotenoids are used as food colorants conferring yellow to red color. This research was designed to study on lipid and β-carotene production by Rhodosporidium diobovatum cultured with different Carbon to Nitrogen (C/N) ratios. Methods: R. diobovatum was cultured in a medium containing 40 g/l glucose (as the carbon source) and different C/N ratios (20, 50, and 80), which were established by adding different amounts of (NH4)2SO4 (3.78, 1.51, and 0.94 g/l) as the source of nitrogen. High performance liquid chromatography, gas chromatography, and microplate reader were used to determine the glucose concentration, lipid production, and β-carotene concentration, respectively. Data were analyzed using IBM SPSS statistics (v. 24). Results: Cultures with a C/N ratio of 50 produced the greatest amount of lipids during 120 h pi. However, lipid synthesis in the first 48 h pi was very low for all three C/N ratios. Analyses of the lipid composition revealed that oleic acid and linoleic acid were the dominant (60%) fatty acids. Cultures with a C/N ratio of 50 also produced the greatest amount of β-carotene. Conclusion: R. diobovatum in the C/N of 50 culture medium resulted in greater concentrations of lipid and β-carotene. Defining the optimum C/N ratio will enable development of optimized bioprocess engineering parameters for scale-up production of lipid and β-carotene in food industries by this yeast species.

73-78

Authors: H. Sarhadi, J. Sadeghizadeh-Yazdi

Background: Modified Atmosphere Packaging (MAP) is one of the most convenient packaging methods that could be useful in reducing the wastes and extending the crops’ shelf-life. This research aimed to assess the impact of MAP containing high concentrations of carbon dioxide on physicochemical, microbial, and sensorial properties of Iranian Mazafati date. Methods: Date samples were packed separately in control and MAP treatment groups and stored at 5 and 25 °C. After 30, 60, and 90 storage days, acidity, Brix index, total count of bacteria, molds, and yeast, texture hardness, wettability, flavor, color changes of samples were evaluated. The data were analyzed by MSTAT-C software. Results: Acidity, Brix, and microbial loads in the MAP treatment groups were signifi-cantly (p<0.05) lower than control group. Hardness values of the date samples were significantly (p<0.05) decreased during 30, 60, and 90 days of storage time using MAP with low temperature. The MAP group at 5 °C and control group at 25 °C had the highest and lowest sensorial scores, respectively showing significant differences (p<0.05). Conclusion: The results of this study showed that application of the MAP method along with low temperature increases the shelf-life of Iranian Mazafati dates.

1-1

Authors: jfqhc

-

8-15

Authors: D. Al-taghlubee, A. Misaghi, P. Shayan, A. Akhondzadeh Basti, H. Gandomi, D. Shayan

Background: Meat species adulteration has become a problem of concern. This study aimed to compare two previously published multiplex Polymerase Chain Reaction (PCR) methods for meat species authentication. Methods: The primers used in the first multiplex PCR involved species-specific reverse primer for sheep, goat, cattle, pig, and donkey with universal forward primer. In the second multiplex PCR, the primers included species-specific forward and reverse primer for pork, lamb, ostrich, horse, and cow. The extracted DNA was then amplified with species-specific primers and with mix primers separately in the respective multiplex PCR. Results: The first multiplex PCR was accompanied with cross reactivity, whereas the second multiplex PCR was specific as expected for pork, lamb, ostrich, horse, and cow. The first set of multiplex PCR showed not always amplification of all species-specific DNAs with a mixture of DNA from mentioned animals. Regarding the second set of primers, the extracted DNA of different meat species was amplified with corresponding species primers as simplex PCR resulting in specific amplicons for species DNA prepared from sheep, ostrich, horse, pig, and cattle with the specific PCR products of 119, 155, 253, 100, and 311 bp, respectively. Conclusion: Based on the present investigation, we recommend the multiplex PCR with the second set of primers included species-specific forward and reverse primers for species authentication of five meat types, including pork, lamb, ostrich, horse, as well as cow.

25-29

Authors: S. Ahmed, A.F.M.I.U. Zim, S. Rahman, S. Ghosh, A. Chhetri, M.S. Ali

Background: Milk is considered as one of the highly nutritious food for human. This study was undertaken to evaluate the physicochemical as well as the microbial quality of pasteurized milk of different brands available in Chittagong, Bangladesh. Methods: Five types of branded pasteurized liquid milk were collected from retail markets of Chittagong, Bangladesh. Physicochemical analyses were carried out in order to determine the levels of pH, acidity, fat, protein, casein, specific gravity, Solids-Not-Fat (SNF), and total solids of the samples. Also, the samples were analyzed microbiologically to assess the total microbial loads and coliforms. Statistical analysis was done using SPSS software version 23.0. Results: The ranges of physicochemical parameters of the samples were determined, including specific gravity (1.024-1.031), pH (5.8-6.7), acidity (0.17±0.01-0.37±0.01%), total solids content (8.17-12.27%), SNF (7.28-8.49%), fat (0.89-3.78%), protein (3.42±0.09-3.63±0.02%), and casein content (2.66±0.07-2.82±0.02%). Statistically significant differences (p<0.05) were recorded among different milk brands for all physicochemical parameters except specific gravity. The highest and lowest amounts of total bacterial counts were 1150400 and 35500 CFU/ml, respectively. A significant difference (p<0.05) was found in bacterial loads among different brands of pasteurized milk. Conclusion: This survey revealed that different brands of Bangladeshi pasteurized milk did not maintain the standard and acceptable quality.

37-40

Authors: G. Zhelyazkov, D. Stratev

Background: Fish meat is outlined with high nutritional value having essential amino acids, unsaturated fatty acids, mineral and vitamins. In this short report, we compared the meat quality of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta fario) farmed in Bulgaria. Methods: Ten fishes from each species were purchased from a fish farm and their morphological parameters were determined. The technological properties of meat were analyzed such as water holding capacity and cooking loss as well as chemical composition such as water content, protein, fat, dry matter, and ash. Results were processed by STATISTICA 6.0 software. Results: Higher values were significantly determined in brown trout for standard body length (p<0.05), body height (p<0.001), and body width (p<0.01); while differences in total body length were not relevant (p>0.05). Water holding capacity of rainbow trout meat (9.49±3.86%) was considerably better (p<0.001) than that of brown trout meat (15.85±1.11%). Cooking loss in rainbow trout (31.78±6.17%) was lower (p<0.001) than that of brown trout meat (44.48±4.20%). Protein, fat, and dry matter contents were higher in brown trout (p<0.001). No statistically significant differences were found out with respect to ash content (p>0.05). Conclusion: Meat of rainbow trout cultivated in Bulgarian farm exhibited better technological properties than that of cultivated brown trout; however, nutritional value of brown trout meat was superior.

117-117

Authors: jfqhc

-

128-133

Authors: F. Faparusi, E.A. Alagamba

Background: Several health problems may be occurred due to consumption of mycotoxin-contaminated foods and feeds. The maize and oilseeds, as the main components of poultry feeds are susceptible to mould contamination and mycotoxin production. The aim of this study was to determine the presence of toxigenic Aspergillus spp. in poultry feeds from Ilaro, Nigeria. Methods: A total of 60 poultry feed samples were collected from five (A-E) feed millers in Ilaro, Nigeria. The feeds were classified into four groups, including broiler super starter, broiler starter, boiler grower mash, and broiler finisher mash. Moulds were isolated by spread plate technique and were identified using the conventional morphological method. The toxigenic potentials of the isolates were determined by ammonia vapor test. Statistical analysis was carried out using SPSS version 20. Results: The results showed that all feed samples (100%) were contaminated with Aspergillus spp. Out of 93 Aspergillus spp. isolates, A. flavus (40 of 93) had the most prevalence, while A. parasiticus (8 of 93) was the least. Totally, 15 out of 93 (16.1%) Aspergillus spp. strains showed toxin production potentials. Conclusion: The presence of toxigenic Aspergillus in the feed leads to the secretion of hazardous toxins especially aflatoxins which can contaminate poultry meat endangering food chain. Consequently, there is an urgent need to create more awareness on the health implications of feeding poultry with mycotoxins-contaminated feeds in this region of Nigeria.

140-145

Authors: H. Kochakkhani, P. Dehghan, M.H. Moosavy

Background: In recent years, food-borne outbreaks have been increased by consumption of raw fruits and vegetables contaminated with bacterial pathogens like Salmonella spp. in many countries. This study was designed in order to molecular detection of Salmonella in Ready-to-Eat Vegetable Salad (REVS) consumed in restaurants of Tabriz, North-West of Iran. Methods: In this cross-sectional study, 90 REVS samples were randomly collected from five different areas of the Tabriz, Iran from February to June 2016. The presence of S. enterica serovar Typhimurium isolates was assessed using real-time polymerase chain reaction technique. Data analysis was performed using SPSS software version 19.0. Results: Out of 90 REVS samples, 4 (4.44%) were found to be positive with S. enterica serovar Typhimurium. There was no significant difference between S. enetrica serovar Typhimurium prevalence in various areas (p>0.05). Conclusion: This survey showed that REVS consumed in restaurants of Tabriz, Iran may have public health risk in terms of presence of S. enterica serovar Typhimurium; so, it is required to improve the food safety standards in this area. Next investigations should be done to find the antimicrobial susceptibility of the identified isolates.

154-160

Authors: F. Aminharati, M.H. Ehrampoush, M.M. Soltan Dallal, A.A. Dehghani Tafti, M. Yaseri, Z. Rajabi

Background: Enterotoxigenic Escherichia coli (ETEC) is one of the most important agents of travelers’ diarrheal diseases in the developing countries. The main purpose of this study was to determine the association of ETEC outbreaks with climatic and demographic variables in Yazd province of Iran. Methods: This study was done on 729 food-borne disease rectal swab samples, which gathered during 48 ETEC outbreaks in Yazd province from 2012 to 2016. The isolates were identified by biochemical tests, serotyping, and heat labile enterotoxin assays in Vero cell line culture. The climatic data was gathered from Iran’s Meteorological Organization and Yazd synoptic stations. Data were analyzed by Stata statistical software. Results: The rates of ETEC outbreaks in Ashkezar, Mehriz, and Taft were significantly (p<0.05) more than the other cities of Yazd province. A positive relationship was found between suspended dust condition and the IR of ETEC outbreaks. The IR of ETEC outbreak in autumn was more than the other seasons. Conclusion: The present work showed the association of ETEC outbreaks with some factors such as demographic features, location status, and climate variations.

81-82

Authors: A. Hlali

-

84-88

Authors: W.A. Istifanus, S.M. Panda

Background: Parasitic contamination of fruits and vegetables is one of the major causes of gastroenteritis in many parts of the world. The aim of this study was to determine the parasitic contamination in fruits and vegetables in the Bauchi area, North-East Nigeria. Methods: From May to July 2017, a total of 776 samples comprising 182 samples of four different types of fruits, and 594 samples of six different types of vegetables were screened by simple floatation and formol-ether concentration techniques. The isolated parasitic ova and cysts were identified on the basis of morphological characteristics with reference to the standard keys. The data were analyzed by chi-square test using SPSS computer software version 21.0. Results: Totally, 26 out of 182 fruit samples (14.3%), and 82 out of 594 vegetable samples (13.8%) were contaminated with various parasitic ova and cysts. Ascaris lumbricoides was the most common parasitic contaminant in both fruits and vegetable samples. The differences were not statistically significant in the prevalence rates of contamination among different types of fruits and vegetables (p>0.05). Conclusion: This study showed that contaminated fresh fruits and vegetables consumed in Bauchi, Nigeria are the major sources of parasitic infections and may have serious public health implications. It seems that health education with respect to personal hygiene and eating habits is the most practical and useful approach in order to desired control in the studied area. The local people must be effectively trained for proper washing and disinfecting of the fruits and vegetables prior to consumption.

94-101

Authors: A.N. Zifruddin, K.L. Thong

Background: Salmonella is one of the most common food-borne pathogens that can cause illness. In this study, the sensitivity and the specificity of Aptamer-Magnetic bead Separation-Polymerase Chain Reaction (AMS-PCR) method were determined for Salmonella spp. detection. Methods: Different concentrations of Salmonella enterica were mixed with streptavidin-magnetic beads coated with biotinylated DNA aptamer. The bound bacteria were eluted and tested with PCR targeting the invA gene of Salmonella. Ten different serovars of Salmonella enterica and four non-Salmonella were tested to determine the specificity of the DNA aptamer. For field application, 14 different food samples were tested and compared with the culture method. Results: The limit of detection of AMS-PCR method was 102 CFU/ml which was 10 times more sensitive than conventional PCR without AMS (103 CFU/ml). The AMS-PCR assay showed high specificity as it detected ten different serovars of Salmonella enterica with no cross-reactivity with other food-borne pathogens. AMS-PCR reduced the analytical duration from 6 to 7 h instead of 4 days by the culture method. Conclusion: In comparison with the culture method, AMS helped to improve the upstream sample preparation in reducing the pre-enrichment and enrichment times. So, it seems that combining AMS with PCR is cost-effective and time-saving. In addition, it is highly specific for monitoring of Salmonella spp. in food chain.

109-115

Authors: Y. Shahbazi, N. Shavisi

Background: One of the most well-known Iranian traditional cheeses is Koozeh. The aim of present work was to evaluate the survival of L. monocytogenes during ripening of Iranian traditional Koozeh cheese made from raw ewe's milk. Methods: A 2-factor experimental design was applied to study the effect of ripening conditions, including different temperatures (4, 9, and 14 °C) and different concentrations of NaCl (0, 8, 12, and 15%) on the survival of L. monocytogenes in the Koozeh cheese. Microbial analysis was carried out over a period of 150 days with sampling in every 10 days. SPSS software (v. 16.0) was used for statistical analysis. Results: Three NaCl concentrations (8, 12, and 15%) significantly affect the inactivation L. monocytogenes (p<0.05). After inoculation, L. monocytogenes populations were reduced most rapidly during the first ten days of storage (~0.5-1.5 log Colony Forming Unit/g) at three mentioned temperatures; after that, the bacteria were continually decreased, being below the detection limit (1 log CFU/g) at the end of ripening. Numbers of L. monocytogenes were reduced more effectively at 14 °C storage temperature than 9 and 4 °C (p<0.05). Conclusion: L. monocytogenes was declined drastically during ripening days and eliminated at the end of ripening of Koozeh cheese. L. monocytogenes counts were decreased during ripening of Koozeh cheese under adverse conditions such as high salt concentrations and high temperatures. However, since Iranian Koozeh cheese is made from raw and unpasteurized milk, there are still some concerns about health risk of L. monocytogenes in this product. Also, the effects of temperature and salting parameters on the sensorial properties of Koozeh cheese should be investigated in future.

38-39

Authors: E. Dimitrieska-Stojkovikj

-

41-48

Authors: M. Carvalho, H. Albano, P. Teixeira

Background: Plant-derived Essential Oils (EOs) have shown remarkable antimicrobial activity against spoilage and pathogenic microorganisms isolated from food products. The objective of the current study was to determine in vitro antimicrobial effects of selected EOs against these microorganisms. Methods: Antimicrobial activity of EOs against food-borne and spoilage microorganisms was screened by disk diffusion assay; then, the Minimum Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) were determined. Statistical analysis was done using SPSS 23.0 software for Windows. Results: Oregano and thyme EOs showed the highest antimicrobial activity and the lowest MICs, while anise, fennel, garlic, and ginger showed a lower activity with significant differences (p<0.05). It was demonstrated that Salmonella Typhimurium, Escherichia coli, Proteus mirabilis, and Yersinia enterocolitica were the most sensitive bacteria to all the EOs tested (p<0.05). Among Gram-positive bacteria, Listeria innocua was demonstrated to be the most sensitive to most of the EOs (p<0.05). Furthermore, Staphylococcus aureus and Listeria monocytogenes were shown to be more sensitive than Enterococcus spp. (p<0.05). Yeasts were significantly (p<0.05) more sensitive than bacteria and were inhibited by most of the EOs. Conclusion: The use of the analyzed EOs may be interesting to food processors because of their antimicrobial properties. However, it is necessary to test their use in food products and gauge their sensory implications.

54-60

Authors: Sh. Sotudeh, M. Rabbani Khorasgani , Z. Etemadifar, S.H. Zarkesh-Esfahani

Background: Nowadays, colostrum has been known as a considerable and valuable by-product of large-scale dairy production in the world. The main objective of this study was to evaluate the effects of pasteurization, spray-drying and freeze-drying methods on bacterial loads and Immunoglobulin G (IgG) level of bovine colostrums. Methods: Colostrum samples were collected from the first milking postpartum of Iranian Holstein dairy cattle farms. The samples were treated by pasteurization (60 °C for 30 min and 55 °C for 60 min), spray-drying and freeze-drying methods. Standard Plate Counts (SPC), Escherichia coli count, and Total Coliform Count (TCC) were analyzed at days 1, 10, 20, and 30 of storage. Also, IgG level were assessed at the end of 30-day storage. Statistical analysis was performed using SPSS 17.0 (Chicago, IL, USA) software. Results: Although all four treatments showed direct impact on reduction of SPC, TCC, and E. coli count in colostrum stored at 1, 10, 20, and 30 days, but the spray-drying and freeze-drying methods were significantly (p<0.05) more effective to reduce microbial loads. The mean IgG levels of the samples were 60.35 mg/ml for untreated samples (control); 30.65±6.95 mg/ml for spray-dried treatment; 36.97±6.79 mg/ml for freeze-dried treatment; 28.12±6.53 mg/ml for heated treatment at 60 °C/30 min; and 34.97±9.80 mg/ml for heated treatment at 55 °C/60 min. All four treatments resulted in significant (p<0.05) reduction of the IgG levels. Conclusion: Considering the obtained results, it seems that freeze-drying and spray-drying methods could be more effective than pasteurization ones to enhance quality and shelf life of bovine colostrum for a long time.

72-76

Authors: M.M. Soltan Dallal, R. Mazaheri Nezhad Fard, M.K. Sharifi-Yazdi

Background: Staphylococcus aureus, a Gram-positive bacterium, is the most prevalent food-borne pathogen in most regions of the world. The current study was carried out with the aim of S. aureus isolation from shrimps sold in Tehran, Iran. Furthermore, the genes of mecA as indicator of methicillin-resistant S. aureus, sea, seb, and tsst encoding enterotoxins were studied in the S. aureus isolates. Methods: Totally, 150 fresh and 150 frozen shrimp samples were collected from seafood retailers in Tehran. Isolation of S. aureus from the samples was carried out using conventional methods. The target genes were identified using polymerase chain reaction technique. Data were statistically analyzed using SPSS v. 11.5 software. Results: Out of 150 fresh and 150 frozen samples, 84 samples (28%) were contaminated with S. aureus. The contamination rate in fresh samples (22%) was significantly (p<0.05) lower than in frozen samples (34%). Totally, prevalence rates of sea, seb, tsst, and mecA genes in the isolates were 39.3, 15.5, 4.8, and 28.6%, respectively showing significant (p<0.05) differences. Conclusion: High prevalence rates of enterotoxigenic and also antibiotic resistance genes in S. aureus isolated from shrimp samples in the current study highlighted worries about risk of staphylococcal food poisoning in Iranian shrimp consumers.