Category Archives: Decontamination Microbial

Research – Microbial Diversity of Anaerobic-Fermented Coffee and Potential for Inhibiting Ochratoxin-Produced Aspergillus niger

MDPI

Abstract

Coffee flavor considerably depends on the fermentation process, with contributing factors including fermentation temperature, oxygen concentration, and microbial diversity. Efficient controlling of the fermentation can improve the quality of coffee beverages. Therefore, several studies on coffee fermentation processes have been conducted in various regions. The objective of this study was to assess the microbial diversity of coffee beans undergoing anaerobic fermentation at various temperatures (4 °C or 37 °C) and fermentation durations (12 h or 36 h) using full-length 16S rRNA sequencing. This analysis aimed to evaluate the inhibitory effects of the fermented metabolites against ochratoxin-producing Aspergillus niger. From our results, Acetobacter was identified as the dominant microbial community at higher fermentation temperatures, whereas Leuconostoc and Gluconobacter were the dominant genera at lower temperatures. However, at lower temperatures, changes in microbial communities were relatively slow. This study expands our knowledge of the microbial diversity involved in the anaerobic fermentation of coffee beans in Taiwan. The findings of this study can be used in future research to cultivate microorganisms linked to the quality and improve the quality of coffee beverages through fermentation.

Research – Trends in Food Pathogens Risk Attenuation

MDPI

Abstract

Foodborne pathogens represent one of the most dangerous threats to public health along the food chain all over the world. Over time, many methods were studied for pathogen inhibition in food, such as the development of novel packaging materials with enhanced properties for microorganisms’ growth inhibition (coatings, films) and the use of emerging technologies, like ultrasound, radio frequency or microwave. The aim of this study was to evaluate the current trends in the food industry for pathogenic microorganisms’ inhibition and food preservation in two directions, namely technology used for food processing and novel packaging materials development. Five technologies were discussed in this study, namely high-voltage atmospheric cold plasma (HVACP), High-Pressure Processing (HPP), microwaves, radio frequency (RF) heating and ultrasound. These technologies proved to be efficient in the reduction of pathogenic microbial loads in different food products. Further, a series of studies were performed, related to novel packaging material development, by using a series of antimicrobial agents such as natural extracts, bacteriocins or antimicrobial nanoparticles. These materials proved to be efficient in the inhibition of a wide range of microorganisms, including Gram-negative and Gram-positive bacteria, fungi and yeasts.

Research – The Effect of Different Organic Acids and Their Combination on the Cell Barrier and Biofilm of Escherichia coli

MDPI

Abstract

Organic acids are natural antimicrobial compounds commonly used in the food industry. In this study, acetic, lactic, butyric, citric, and malic acid at minimum inhibitory concentrations and their combinations at optimal inhibition concentrations were used to treat E. coli, and the effects on the cell barrier and biofilm of E. coli were evaluated. Acetic acid showed the highest membrane-damaging effect, while citric acid and malic acid could specifically damage the cell wall of E. coli, leading to alkaline phosphatase leakage. The RT-qPCR results showed that organic acids upregulated the membrane-protein-related genes of E. coli, and the combination of organic acids had a wider range of effects than single organic acid treatment. Moreover, organic acids inhibited the formation of E. coli biofilm and cellular activity within the biofilm. This study showed that the combination of organic acids plays a synergistic inhibitory role mainly through multiple destructive effects on the cell barrier and exhibited synergistic anti-biofilm effects. The three–three combination of acetic, lactic acid, and a third organic acid (butyric, citric, or malic) can play a better synergistic antibacterial effect than the two-pair combination of acetic and lactic acid. These findings have implications for the usage, development, and optimization of organic acid combinations.

Researchers explore the significance of Salmonella-positive foods in the UK.

Food Safety News

Foodborne Pathogen

According to a study, the Salmonella prevalence on tested foods on sale in the United Kingdom was low but highest for imported frozen chicken.

Researchers from the Quadram Institute and the University of East Anglia in England isolated Salmonella from 42 food samples.

Salmonella isolates collected from food using whole genome sequencing (WGS) were compared to isolates from humans in the UK.

Raw foods were collected at retail in Norfolk, including 311 samples each of chicken, leafy greens, and pork, 279 prawns, and 157 salmon between May 2018 and November 2019.

RASFF Alert – Food Poisoning from Long Life Milk

RASFF

Food poisoning from long life milk, from Belgium. in the Netherlands

Research – Scientists assess Listeria risk in three food categories

Food Safety News

Experts have made several recommendations ahead of a potential update to guidelines relating to the control of Listeria in food.

Consumer practices deviating from the intended use of a food highlights the need for improved labeling about correct preparation and businesses need to assess the potential impacts of climate change, said scientists brought together by the United Nation’s Food and Agriculture Organization (FAO) and World Health Organization (WHO).

The FAO/WHO Joint Expert Meeting on Microbiological Risk Assessment (JEMRA) met in Geneva, Switzerland, from late May to early June 2023, to perform risk assessments of Listeria monocytogenes in selected foods using models developed since a previous meeting.

Research – Prevalence and Association of Campylobacter spp., Salmonella spp., and Blastocystis sp. in Poultry

MDPI

Foodborne Pathogen

Abstract

Poultry and poultry meat are considered the most important sources of human campylobacteriosis and salmonellosis. However, data about the occurrence of Campylobacter and Salmonella concomitantly with intestinal protozoa such as Blastocystis sp. in poultry remain very scarce. Therefore, this study aimed to investigate the presence and possible interactions between these three microorganisms in fecal samples from 214 chickens collected either on farms or from live bird markets in Egypt. The results obtained showed that Campylobacter spp., Salmonella spp., and Blastocystis sp. were present in 91.6% (196/214), 44.4% (95/214), and 18.2% (39/214) of tested samples, respectively, highlighting an active circulation of these microorganisms. Moreover, a significant positive correlation was reported between the occurrence of Campylobacter spp. and Blastocystis sp. together with a significant negative correlation between Blastocystis sp. and Salmonella spp. This study confirms the association reported previously between Blastocystis sp. and Campylobacter spp. while disclosing an association between Blastocystis sp. and Salmonella spp.; it also highlights the need to improve studies on the interactions between bacteria and eukaryotes in the gut microbiota of poultry.

Afghanistan – 200 people suffer food poisoning in E. Afghanistan

Asia Pacific

KHOST, Afghanistan, Aug. 7 (Xinhua) — At least 200 people were sickened in food poisoning in east Afghanistan’s Khost province, an official said on Monday.

The incident occurred in Satkai village of Zazai Maidan district on Sunday evening when the villagers attended a charity meal, and all the victims had been taken to nearby hospitals and clinics, said provincial police spokesman Mustaghfar Garbaz.

Without providing more details, the official added that further investigations were underway.

In the meantime, villager and eyewitness Tahir Azimi claimed that around 400 people were sick with the charity meal.

Pakistan – 100 factory workers hospitalised for food poisoning

Dawn

GUJRANWALA: About 100 workers fell ill after eating food from a factory in the Alipur Chatha on Friday.

The condition of 10 workers is said to be critical.

The incident happened in the plywood and chipboard manufacturing factory located on the Gujranwala Road. The condition of the workers deteriorated after having breakfast in the morning.

After having breakfast, about 100 workers fell ill. After their condition deteriorated, they were transferred to different hospitals where doctors diagnosed food poisoning.

The Alipur Chatha Rural Health Centre confirmed food poisoning. The assistant commissioner reviewed the situation while a committee was formed to probe the incident. After the patients were shifted to various hospitals across the region, emergency has been declared in hospitals.

Taiwan – 340 people fall ill from suspected food poisoning in Taoyuan

Focus Taiwan

Taipei, Aug. 5 (CNA) A Vietnamese-French sandwich stand at a traditional market in Taoyuan’s Zhongli District was forced to suspend operations Friday, after scores of its customers reported illnesses from suspected food poisoning, according to local authorities.

An inspection of the street vendor’s premises on Thursday identified 14 issues, including the temperature of the freezer, which was too high to keep food fresh, according to a press release from the city’s Department of Public Health on Friday.

In addition, there were vectors at the site, and the food ingredients were not properly covered or elevated above ground, the public health office said.

As of noon Saturday, 340 people had reported symptoms such as diarrhea, vomiting and fever after eating sandwiches purchased at the stand on Wednesday, the department said, citing reports it had received from hospitals and individuals.

The department’s inspectors have collected samples of the sauces, fillings, and other food items at the Vietnamese-French sandwich stand, as well as knives, cutting boards, and other kitchenware, which will be tested to determine the cause of the suspected food poisoning, the health office said.

If pathogenic microorganisms are found and the matter is confirmed as a food poisoning case, the operators of the food stand may be subject to a fine of between NT$60,000 (US$1,894) and NT$200 million, in accordance with the Act Governing Food Safety and Sanitation, the office said.