1.Effect of thermal treatments on the storage stability of Lactobacillus acidophilus La-14 tamarind juice with or without beta-glucans
Li Yu Zhu ; Yu Hsuan How ; Hasanah Mohd Ghazali ; Lee Sin Chang ; Kar Lin Nyam ; Liew Phing Pui
Malaysian Journal of Microbiology 2021;17(4):424-434
Aims:
This study aimed to evaluate the effect of thermal treatment on the storage stability of Lactobacillus acidophilus
La-14 tamarind juice with or without beta-glucans.
Methodology and results:
Lactobacillus acidophilus incorporated with 6% (w/v) beta-glucans displayed the highest
viability (17.28 log10 CFU/mL) as compared to other beta-glucans concentrations (0-8% w/v). The L. acidophilus with or
without beta-glucans survived more than 80% after 5 h of sequential digestion. Tamarind juice was subjected to different
thermal treatments (76 °C for 30 sec or 90 °C for 60 sec) and incorporated with L. acidophilus with or without betaglucans. Lactobacillus acidophilus in tamarind juice without thermal treatment showed the highest viability (8.69 log10
CFU/mL), followed by thermal treatment at 76 °C for 30 sec (>7 log10 CFU/mL), and thermal treatment at 90 °C for 60
sec showed the lowest viability (>4 log10 CFU/mL), after 21 days at 4 °C. The pH, titratable acidity and viscosity of all L.
acidophilus-tamarind juices demonstrated no changes throughout 21 days at 4 °C. Furthermore, thermal-treated
tamarind juice (90 °C for 60 sec) incorporated with L. acidophilus displayed the least change in total soluble solids (1.99
°Brix), while thermal-treated tamarind juice (90 °C for 60 sec) with L. acidophilus and beta-glucans had the lowest color
change (∆E = 4.46), after 21 days of storage at 4 °C.
Conclusion, significance and impact of study
Thermal treatments (90 °C for 60 sec) had contributed to the stability
of L. acidophilus-tamarind juice with beta-glucans over 21 days of cold storage. This study shows thermal treated
tamarind juice with L. acidophilus and beta-glucans is a potential functional non-dairy beverage catered for lactose
intolerance individuals.
Lactobacillus acidophilus
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Food Microbiology
2.Metagenomic characterization of the culturable bacterial community structure of Tapuy, a Philippine indigenous rice wine, reveals significant presence of potential probiotic bacteria
Thea Coleen F. Sanico ; Paul Mark B. Medina
Acta Medica Philippina 2022;56(17):6-17
Background:
Tapuy is an indigenous fermented rice wine produced in the Northern areas of the Philippines. Fermented foods and drinks have gained interest due to their associated health benefits, attributable to probiotic bacteria in the food items. However, pathogenic bacteria may also be present in fermented food and pose health risks, signifying a need for standardization. Currently, there is limited knowledge on the bacterial content of tapuy.
Objectives:
This study aimed to characterize the bacterial diversity and community structure of culturable bacteria in traditionally fermented tapuy samples, to perform standardization of tapuy fermentation, and to compare the bacterial diversity and community structure of culturable bacteria in laboratory fermented tapuy with that of the traditional samples.
Methods:
Tapuy samples were obtained from four municipalities in Benguet, Philippines. Laboratory fermentation of tapuy was performed simultaneously with the fermentation in the sampling site using a standardized protocol. Samples were plated on de Man, Rogosa, and Sharpe (MRS) agar and NA, and the colonies were harvested for DNA extraction. DNA samples were sent for 16S rDNA metagenomic sequencing.
Results. Metagenomic analysis revealed the presence of many bacterial species that were previously unreported in tapuy. Traditional tapuy samples were composed primarily of members of the genera Bacillus and Lactobacillus in varying proportions. Potential probiotic bacteria were abundant in Kapangan (97.42%) and Sablan (99.89%) field samples. B. wiedmannii was present in all samples and was identified as a harmful species. Laboratory fermentation increased the abundance of potential probiotic bacteria in Itogon and La Trinidad samples (differences of 75.36% and 78.36%, respectively). It decreased the quantity of B. wiedmannii in La Trinidad (a difference of 97.1%). Laboratory fermented samples generally exhibited higher bacterial diversity and species richness compared to field samples.
Conclusions
Traditionally fermented tapuy samples contained a significant proportion of potential probiotic bacteria belonging to the genera Bacillus and Lactobacillus. Laboratory fermented samples were found to have higher bacterial diversity and richness compared to field samples. The significant presence of potential probiotic bacteria suggests that tapuy is a good candidate for development into functional food and a good source of likely probiotic species that could be explored for health applications. The presence of harmful bacteria suggests the need for possible standardization of fermentation practices.
Food Microbiology
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Fermented Foods
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Wine
3.Nutritional and microbiological evaluations of chocolate-coated Chinese chestnut (Castanea mollissima) fruit for commercial use.
Mahamadou E GOUNGA ; Shi-ying XU ; Zhang WANG
Journal of Zhejiang University. Science. B 2008;9(9):675-683
In recent years, China has become an increasingly important and the largest chestnut producer in the world. This study aimed to evaluate the nutritional value and microbiological quality of the roasted freeze-dried Chinese chestnut (Castanea mollissima) (RFDC) coated with dark chocolate (DCC) and milk chocolate (MCC) for industrial use and commercial consumption. Chocolate coating significantly improved the nutritional value of chestnut. RFDC had high levels of starch (66.23%) and fibers (3.85%) while DCC and MCC contained significantly high amounts of sucrose, protein, fat and minerals. Furthermore, the protein content doubled in MCC rather than in DCC. This could be attributed to the different formulations in the two products. Milk powder and whey protein constituted the source of protein in MCC while cocoa powder added to MCC formulation constituted an additional source of minerals. The amino acid profile showed differences in amino acid composition related to the sample's protein content, indicating their good nutritional quality. The moisture contents in all RFDC, DCC and MCC were suitable for industrial processing. These results provide information about the additional nutrients of chocolate-coated chestnut and confirm that the product is an interesting nutritional food. The combination of freeze-drying and chocolate-coating generally results in greater reductions on microbiological loads, extending shelf life of harvested chestnut for commercial application. This is an alternative strategy to add value to chestnut, minimizing the significant losses in harvested fruits and providing a wider range of choices of new products to the consumer disposal.
Cacao
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chemistry
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microbiology
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China
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Fagaceae
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chemistry
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microbiology
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Food Analysis
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Food Handling
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methods
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Food Microbiology
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Food Packaging
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methods
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Fruit
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chemistry
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microbiology
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Nutritive Value
4.Research progress of biosensors in the detection of foodborne pathogens.
Fangbin XIAO ; Rui LIU ; Zhongxu ZHAN ; Gan ZHANG ; Xin WU ; Hengyi XU
Chinese Journal of Biotechnology 2019;35(9):1581-1589
As the main factor leading to foodborne illnesses, foodborne pathogens have been attached great importance by people. The development of simple, rapid, high-sensitivity and low-cost food-borne pathogen detection methods is of great significance in reducing the incidence of foodborne diseases. Biosensor technology is a new micro-analysis technology developed by multi-disciplinary cross-infiltration. It has the characteristics of high sensitivity and fast analysis speed, and is widely used in the detection of food-borne pathogens. This paper introduces the basic principles of biosensors, summarizes the application of common biosensors in the detection of foodborne pathogens, and prospects for future development.
Biosensing Techniques
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Food Microbiology
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Foodborne Diseases
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Humans
5.Quantitative microbiological risk assessment of Salmonella spp. in connmmon catering foods.
Chinese Journal of Preventive Medicine 2008;42(5):312-316
OBJECTIVETo study the relationship between foodborne diseases (FBD) and contamination of Salmonella spp. in catering foods, quantitative microbiological risk assessment (QMRA) of Salmonella spp. was used to evaluate the food material or the ready to eat food.
METHODSThe contamination data of Salmonella spp. in 10 896 food samples of 9 categories of food which were collected by National Food Contamination and Food Borne Disease Surveillance Net, combining with diet consumption data from National Food Nutrition Survey in 2002, were analyzed by the microbiological risk assessment model developed by WHO/FAO or FDA/FSIS of US to predict probability of FBD.
RESULTSThe results of MRA showed that the probability of salmonellosis by consuming ready to eat meat in summer and autumn was 0.20, much higher than the other foods. Although the contamination level in raw poultry was higher than meat, the probability of salmonellosis by raw poultry (9.11 x 10(-6)) was lower than meat (3.14 x 10(-5)) because of the low consumption volume.
CONCLUSIONProbability of FBD was significantly correlated with the volume of food consumption, the status of economy and bacteria contamination level. The level of FBD in summer season was higher than in winter and spring because of ambient temperature.
Food Contamination ; Food Microbiology ; Humans ; Risk Assessment ; Salmonella ; isolation & purification ; Salmonella Food Poisoning ; prevention & control
6.Risk assessment of Listeria monocytogenes in deli meats and vegetable salads.
Chinese Journal of Preventive Medicine 2009;43(9):781-784
OBJECTIVETo analysis risk from Listeria monocytogenes in deli meats and vegetable salads.
METHODSUse Risk Ranger which is a software programme developed by the University of Hobart, Australia and answer 11 questions on affecting the risk from hazards in the specific foods by combining data from national foodborne diseases surveillance network and some references to make semi-quantitative risk assessment for the specific food.
RESULTSRelative risk from Listeria monocytogenes in deli meats and vegetable salads is 61 and 52, respectively. Incidence of listeriosis caused by deli meats-Listeria monocytogenes pairs and vegetable salads-Listeria monocytogenes pairs is 5.4 and 0.2 cases per million people, respectively. Risk from the former is 32 times than that from the latter. By changing the selection for some risk factors in the model, it was known that the risks from two food-hazard combinations could decrease 10 times, if taking necessary actions after processing.
CONCLUSIONDeli meats is a kind of high risk food for listeriosis.
Food Microbiology ; Listeria monocytogenes ; isolation & purification ; Meat Products ; microbiology ; Risk Assessment ; Vegetables ; microbiology
7.Epidemiological Investigation of an Outbreak of Salmonellosis in Gyeongju, Korea.
Seok Ju YOO ; Hyun Sul LIM ; Kwan LEE
Journal of Preventive Medicine and Public Health 2014;47(3):177-181
OBJECTIVES: A salmonellosis outbreak occurred within a community of Gyeongju residents who ingested catered food from a wedding in June 2009. We aimed to epidemiologically investigate the probable vehicle of the infection. METHODS: We conducted a retrospective cohort study on 34 local residents who ingested the wedding food. RESULTS: Among the 34 residents, 31 (91.2%) reported symptoms of infection after eating the food. Among all of the wedding foods, pan-fried foods were highly associated with the diarrheal attack rate. On bacteriological examination, Salmonella species were detected in the pan-fried foods among the leftover foods and in 17 of the 31 stool specimens from the cases. There were five different types of pan-fried foods, but the onset of symptoms was independent of the ingredients used. We found that the pan-fried food was prepared at a food store in Seoul and that eggs were a common ingredient. CONCLUSIONS: The major cause of the salmonellosis in this population was presumed to be the pan-fried food prepared with contaminated eggs. These food items might have been partially undercooked because of their irregular shape, which allowed the Salmonella species to survive and multiply before ingestion.
Cohort Studies
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*Disease Outbreaks
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Eggs/microbiology
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Feces/microbiology
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*Food Microbiology
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Fruit/microbiology
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Humans
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Republic of Korea/epidemiology
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Retrospective Studies
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Salmonella/*isolation & purification
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Salmonella Food Poisoning/*epidemiology
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Time Factors
8.Natural occurrence of masked deoxynivalenol and multi-mycotoxins in cereals from China harvested in 2007 and 2008.
Feng-qin LI ; Chuan-chuan YU ; Bing SHAO ; Wei WANG ; Hong-xia YU
Chinese Journal of Preventive Medicine 2011;45(1):57-63
OBJECTIVETo elucidate the natural occurrence of masked deoxynivalenol (DON-3-G) and other multi-mycotoxins in cereals from parts of China.
METHODSA total of 446 corn and wheat samples harvested in 2007 and 2008 collected from Henan, Hebei, Guangxi, Anhui, Sichuan, Chongqing and Jiangsu provinces were analyzed for DON-3-G and other multi-mycotoxins (including deoxynivalenol (DON), zearalenone (ZEN), nivalenol (NIV), et al) by UPLC-MS/MS.
RESULTSCorn and wheat samples were mainly contaminated by DON and its derivatives as well as ZEN.88% (169/192) of wheat samples were positive for DON (range: 1.5 - 590.7 µg/kg; median: 30.8 µg/kg); 22.9% (44/192) of wheat samples were contaminated with ZEN (range: 1.7 - 3425.0 µg/kg; median: 8.0 µg/kg) and six samples contained ZEN concentration higher than the ZEN tolerance limit of 60 µg/kg. DON was detected in 50.5% (103/204) corn samples (range: 1.6 - 4374.4 µg/kg; median: 94.9 µg/kg); Seven samples contained DON exceeding the tolerance limit of 1000 µg/kg for DON. Additionally, ZEN was found in 41.7% (85/204) corn samples with the concentration between 1.6 µg/kg and 4808.7 µg/kg (median: 48.5 µg/kg) and there were 37 corn samples with ZEN level in the excess of tolerance limit for ZEN (60 µg/kg). DON-3-G was detected in corn and wheat samples for the first time in China with the median level of 21.4 µg/kg and 34.6 µg/kg for wheat and corn, respectively. Wheat was more heavily contaminated with DON-3-G than both 3-acetyl-DON (3-A-DON, median: 4.1 µg/kg) and 15-acetyl-DON (15-A-DON, median: 3.1 µg/kg) (t values were 5.111 and 5.966, respectively, both P values < 0.01). While, the level of 15-A-DON (median: 48.6 µg/kg) in corn was higher than 3-A-DON (median: 6.8 µg/kg) (t = -3.579, P < 0.01). The concentration of DON, DON-3-G, 3-A-DON, 15-A-DON and ZEN in corn were higher than that in wheat (Z values were -3.492, -1.960, -2.467, -8.711 and -6.272, respectively, all P values < 0.05). Wheat (median: 29.0 µg/kg) contained higher NIV in comparison with corn (median: 18.2 µg/kg, Z = -2.086, P < 0.05).
CONCLUSIONWheat and corn samples from parts of China were contaminated with multi-mycotoxins and DON was the predominant;in comparison of wheat, corn was more heavily contaminated with DON, DON-3-G, 3-A-DON, 15-A-DON and ZEN.
China ; Edible Grain ; chemistry ; microbiology ; Food Contamination ; Food Microbiology ; Fusarium ; isolation & purification ; Mycotoxins ; isolation & purification ; Trichothecenes ; isolation & purification ; Triticum ; chemistry ; microbiology ; Zea mays ; chemistry ; microbiology
9.Prevalence and molecular characteristics of Listeria monocytogenes in cooked products and its comparison with isolates from listeriosis cases.
Hong WANG ; Lijuan LUO ; Zhengdong ZHANG ; Jianping DENG ; Yan WANG ; Yimao MIAO ; Ling ZHANG ; Xi CHEN ; Xiang LIU ; Songsong SUN ; Bo XIAO ; Qun LI ; Changyun YE
Frontiers of Medicine 2018;12(1):104-112
This study aimed to investigate the prevalence and molecular characteristics of Listeria monocytogenes in cooked products in Zigong City, China. The overall occurrence of the L. monocytogenes in the ready-to-eat (RTE) shops and mutton restaurants surveyed was 16.2% (141/873). An occurrence of 13.5% was observed in RTE pork, 6.5% in RTE vegetables, and more than 24.0% in either cooked mutton or cooked haggis. Serotype 1/2b (45.4%), 1/2a (33.3%), and 1/2c (14.2%) were the predominant types. By comparing the clonal complexes (CCs) based on multilocus sequence typing (MLST) of the L. monocytogenes from cooked foods in Zigong City and 33 listeriosis cases from different districts of China, CC87, CC9, CC8, and CC3 were showed to be prevalent in cooked products and CC87 and CC3 were the first two frequent types in the 33 clinic-source strains. All CC87 stains harbored the newly reported Listeria pathogenicity island 4 (LIPI-4) gene fragment ptsA, and all CC3 strains possessed the Listeria pathogenicity island 3 (LIPI-3) gene fragment llsX. These may increase the occurrence of the strains belonging to CC87 and CC3 in listeriosis cases in China and also underline the risk of infection owing to the consumption of the cooked products from Zigong. ST619 (serotype 1/2b) harbored both llsX and ptsA, indicating a potential hypervirulent sequence type in Zigong.
China
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epidemiology
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Cooking
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Fast Foods
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microbiology
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Food Contamination
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Food Microbiology
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Humans
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Listeria monocytogenes
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genetics
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pathogenicity
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Listeriosis
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epidemiology
;
microbiology
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Meat
;
microbiology
;
Multilocus Sequence Typing
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Prevalence
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Seasons