Food Hygiene
Mehdi Fathollahi; Majid Aminzare; Mehran Mohseni; Hassan Hassanzadazar
Volume 10, Issue 4 , December 2019, , Pages 299-305
Abstract
This study aimed to evaluate the composition, antioxidant capacity and antibacterial effects of Pistacia atlantica subsp. kurdica (baneh) essential oil on some important bacteria in food safety. Essential oil was derived using hydro-distillation method of the baneh fruits. Essential oil composition was ...
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This study aimed to evaluate the composition, antioxidant capacity and antibacterial effects of Pistacia atlantica subsp. kurdica (baneh) essential oil on some important bacteria in food safety. Essential oil was derived using hydro-distillation method of the baneh fruits. Essential oil composition was determined using gas chromatography–mass spectrometry. The 2,2′-azinobis-(3-ethylbenzothiaziline-6-sulfonate; ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods were used to evaluate antioxidant activity and Folin-Ciocalteu method was used to determine total phenolic content of essential oil. The antibacterial effect of the essential oil against six pathogen bacteria was determined using minimum inhibitory concentration, minimum bactericidal concentration and disc diffusion methods. Monoterpene and sesquiterpene hydrocarbons were main compounds of total identified constituents in the essential oil (approximately 93.50% and 5.45%, respectively). The main compounds were α-pinene, myrcene, limonene, β-pinene and γ-terpineol, respectively. The mean concentration of essential oil providing 50.00% inhibition was 7.54 ± 0.01 mg mL-1. Dose-dependent and scavenging activities were seen in DPPH and ABTS tests and total phenolic content within test range of concentrations (0.0625 to 4.00 mg mL-1). The highest DPPH radical scavenging activity (48.67 ± 0.84%) was seen at a concentration of 4 mg mL-1. The responses of essential oil concentrations to ABTS assay were quite similar to the DPPH reaction, especially in higher concentrations. Both antimicrobial methods demonstrated that the essential oil had broader antibacterial effects against the Gram-positive bacteria than the tested Gram-negative bacteria. Essential oil of Pistachia atlantica subsp. kurdica can be one of the performing essential oils to be used as a preservative in food industry to increase food safety and reduce food pathogens risks.
Hassan Hassanzadazar; Ali Ehsani; Karim Mardani
Volume 5, Issue 3 , July 2014, , Pages 169-175
Abstract
Viability of probiotic bacteria in food during maintenance and time of consuming in food has become a challenge in food hygiene and technology and is important for representing their beneficial health effects. The aim of this study was to determine the survival of probiotic Enterococcus faecium derived ...
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Viability of probiotic bacteria in food during maintenance and time of consuming in food has become a challenge in food hygiene and technology and is important for representing their beneficial health effects. The aim of this study was to determine the survival of probiotic Enterococcus faecium derived from Koopeh cheese added to industrial Iranian ultra-filtrated (UF) cheese and screening for antimicrobial activity of Enterococcus faecium against Listeria monocytogenes during two months of cheese ripening. Physiochemical and standard microbial methods were used for isolation of Enterococcus strains in cheese samples. The initial number of lactic acid bacteria (LAB) as starter culture was 6 Log g-1 in control samples. The counts started to decrease slightly after day seven (p < 0.05) and dropped to 5 Log g-1 at the end of 60 days. The count of LAB in the test groups decreased to 11 Log g-1 on the day 60 of ripening. The number of Enterococcus faecium was 6 Log g-1 on the day 60. The count of Listeria monocytogenes after 60 days of ripening in blank sample decreased 1 Log but in test samples with protective strain decreased 3 Log in 30 days and reached to zero at 45 days. There were not significant (p < 0.05) changes in chemical parameters such as fat, protein and total solid of UF cheese treatment groups. The results showed that Enterococcus faecium of Koopeh cheese was suitable for development of an acceptable probiotic UF cheese and could be adapted to industrial production of UF cheese.
Seyed Mehdi Razavi Rohani; Javad Aliakbarlu; Ali Ehsani; Hassan Hassanzadazar
Volume 4, Issue 2 , June 2013, , Pages 115-118
Abstract
Biogenic amines (BA) are nitrogenous compounds that possess biological activity. The source of production is the microbial decarboxylation of amino acids. This compounds are found in various types of cheese. The aim of this work was to evaluate the BA content of some traditional cheeses in West Azerbaijan ...
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Biogenic amines (BA) are nitrogenous compounds that possess biological activity. The source of production is the microbial decarboxylation of amino acids. This compounds are found in various types of cheese. The aim of this work was to evaluate the BA content of some traditional cheeses in West Azerbaijan province Iran. For this purpose, 70 samples of Koopeh, 10 samples of Lighvan and 5 samples of Red Salmas cheeses were obtained from local supermarkets of different cities of West Azerbaijan province. After preparation of samples, biogenic amines content was evaluated by modified HPLC method. The presence of histamine, cadaverine, putrescine and tyramine in tested cheeses were observed. Total amount of biogenic amines was highest in Red Salmas cheese with 1426.91 ppm. It followed by Lighvan cheese and Koopeh cheese with 1008.98 and 517.71 ppm, respectively. Putrescine, cadaverine, histamine and tyramine were detected in Koopeh cheese at levels up to 156.09, 282.34, 70.80, 8.48 ppm respectively. These amines were detected also in Lighvan cheese at levels up to 277.53, 342.74, 37.58, 351.12 ppm and in Red Salmas cheese samples at levels up to 438.03, 701.05, 105.21, 182.62 ppm, respectively. Large amounts of biogenic amines can indicate non hygienic conditions and contamination of used milk for cheese production.
Hassan Hassanzadazar; Ali Ehsani; Karim Mardani; Javad Hesari
Volume 3, Issue 3 , September 2012, , Pages 181-185
Abstract
Lactobacillus strains are a major part of the probiotics, microflora of the intestine and of fermented dairy products, and are found in a variety of environments. The aim of this study was to find out the ability of bile and acid tolerance and antibacterial properties of the twenty eight isolates of ...
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Lactobacillus strains are a major part of the probiotics, microflora of the intestine and of fermented dairy products, and are found in a variety of environments. The aim of this study was to find out the ability of bile and acid tolerance and antibacterial properties of the twenty eight isolates of three group lactobacilli namely Lactobacillus plantarum, Lactobacillus casei and Lactobacillus delbruki. For this purpose Twenty eight different Lactobacillus strains that isolated from Koozeh cheese as a traditional cheese were screened. The acid tolerance test was studied under pH 2.0 and 3.0 with 7.5 as control. The cell count for the acid tolerance test was obtained at an interval of 0, 1, 2 and 3 hours respectively and was pour plated on Man, Rogosa, and Sharpe (MRS) agar to be incubated at 37 °C for 24 hours. All cells were selected for bile tolerance test in MRS broth containing bile concentrations of 0% as control and 0.3% as test. Then cell counts were enumerated after 24 hours of incubation on MRS agar. Results showed twenty seven isolates did not have ability to tolerate acid and bile salts and antimicrobial activity against four indicator bacteria included Eshirichia coli, Listeria monocytogenesis, bacillus cereus, Salmonella entritidis. Only one Isolate namely Lactobacillus casei could tolerate acid and bile salt and had antibacterial activity against of L. monocytogenesis. Therefore we can consider this strain as a native probiotic but extra examinations was required.
