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Should we use electric Jet-air Dryers to dry hands? Or should we be scared back to use paper towels?

A study published recently in the Journal of Hospital Infection compared the effect of hand-drying methods on the potential risks of pathogen dissemination. A comparison was made between hand drying using paper towels (PT) or jet air dryer (JAD; Dyson) and their impact on the contamination levels in the bathrooms in several European countries.
While much attention is being paid to hand washing methods, less attention is being paid to optimal hand drying methods. Hand drying can play a key role in the prevention of the transfer of microorganisms among people and their dissemination in the environment. The relative risk of dissemination of microorganisms that are not removed from hands during washing, and remaining on the wet hands, was studied.
The main reason to use hot air dryers is to reduce paper waste. However, several studies have shown that some hand-drying methods are linked to create a greater risk of dissemination of residual microorganisms from hands after (particularly suboptimal) hand washing.
The study found lower contamination in PT versus JAD bathrooms. JAD dispenser resulted in a significantly higher total bacteria count on the dispenser surfaces than PT in all sites (median: 100–300 vs 0–10 cfu; all P < 0.0001).
Considerably more bacteria were recovered from bathroom floors using JAD (median: 24 vs 191 cfu, P < 0.00001) in the UK and France. Recovery of Methicillin-susceptible Staphylococcus aureus was three times more frequent and six-fold higher for JAD vs PT surfaces (both P < 0.0001) in the UK. Meticillin-resistant S. aureus recovery was three times more frequent (21 vs 7 cfu) from JAD versus PT surfaces or floors. The data from this study shows that 80% of airborne bacteria were recovered in the first 10 of 15 min following use of a JAD.
Enterococci and Extended-Spectrum β Lactamase (ESBL)-producing bacteria were significantly more frequently recovered from JAD versus PT washroom floors (P < 0.0001) in the UK. In France, ESBL-producing bacteria were recovered from dust twice as often during JAD versus PT use. There was also the higher recovery of ESBL-producing bacteria from floors of JAD washrooms. There were other significant differences in surface bacterial contamination, with higher levels of JAD versus PT bathrooms (e.g. higher faecal and antibiotic-resistant bacteria).  
JADs dry hands via high-velocity shearing forces that remove both water and bacteria from hands, propel them into the air and on to bathroom surfaces. By contrast, PTs absorb water and bacteria with consequently less potential for bacterial contamination of the environment.
This data is in agreement with other studies. As a result, electric hand dryers are not suited to clinical settings, and perhaps inappropriate for food manufacturing facilities. During the flu season, when there is high influenza and norovirus activity, airborne dispersal of pathogens, could be a public health concern.
The study found clear differences in environmental bacterial contamination, between the two hand drying methods. With JAD showing higher levels of contamination, more spreading of bacteria, more Enterococci, MRSA and ESBL-producing bacteria than PT. Therefore it is difficult to rationalize a hand-drying method that is associated with considerably greater susceptibility for microorganisms’ dispersal when potential pathogens are potentially present.

Defense against antibiotic resistance- bacteria-eating bacteria

In an attention-grabbing article published at NPR it is suggested to use bacteria-eating bacteria as a new mean to combat antibiotic-resistant bacteria. In a study funded by Defense Advanced Research Projects Agency (DARPA) Brad Ringeisen deputy director of the Biological Technologies Office at the DARPA claims that microbe-eating microbes are found in almost every ecosystem on Earth.
The study funded by DARPA showed that predatory bacteria will attack many disease-causing bacteria that have developed resistance to antibiotics. The main organism they worked with is Bdellovibrio (a small (0.3 to 0.4 micrometers wide, and 0.8-1.2 micrometers long), highly motile (with a single polar  flagellum), vibrio shaped, mono flagellated, gram-negative bacteria).
Bdellovibrio life cycle is described as:
  1. Due to its high speed of movement, the Bdellovibriorams the target cell
  2. It quickly attaches to the host cell envelope by its non-flagellated end, presumably drilling into the host cell wall.
  3. A hole appears in the host’s cell wall at the site of attachment and the parasite invades the host periplasm. The flagellum is lost during penetration and remains outside the host.
  4. The Bdellovibriogrows with multiple copies of the genome.
  5. As the food supply becomes exhausted, the filament divides by multiple fission, splitting into several new Bdellovibrio bacteria.
  6. The host cell swells, ruptures and the Bdellovibrio new cells are liberated.
Bdellovibrio can attack common bacteria six times its size. The research found that Bdellovibrio attacked 145/168 tested human pathogens. Bdellovibrio actually bores into larger bacteria and eats them from the inside out.
According to Liz Sockett, a professor of bacterial genetics at Nottingham University in the UK, the Bdellovibrio uses it motility to get to it’s pray and then latches on, using tiny appendages “which are little grappling hooks on the surface.” Once attached to its pray, it kills the target pathogen. The attacked organisms do not appear to develop a resistance mechanism to Bdellovibrio.
Nancy Connell, a microbial geneticist from Rutgers University studied anthrax and all sorts of other deadly pathogens say that exploring these predatory bacteria is the most exciting work she’s done in her career. “This is the first time that I have felt we might have a way through many of these different infections.”
Connell and her lab studied the use of Bdellovibrio to help fight lung infections in rats. Bdellovibrio reduced significantly the disease-causing bacteria but did not totally eliminate it.  While not replacing antibiotics, it could be useful if given as a preventive in advance of an anticipated germ warfare attack, or it could also work in a patient who has an infection that simply doesn’t respond to antibiotics, Connell says. Of course, we won’t know whether it works at all in people until researchers can put it to the test.

Fluid Milk Spoilage by Psychrotolerant Spores and Shelf-Life Improvement

Cornell University researchers created a new predictive model that examines spore-forming bacteria and their impact on pasteurized milk shelf life, published in the August issue of the Journal of Dairy Science entitled “Psychrotolerant spore-former growth characterization for the development of a dairy spoilage predictive model”. The goal of the research was to create a mathematical model to increase the product shelf life and have a more meaningful and accurate way to estimate the shelf life. This can reduce food waste and reduce food spoilage, by a better understanding of the parameters driving spoilage.
The researchers characterized the ability to germinate and grow 14 psychrotolerant spore-formers. The organisms used representing the most common Bacillales subtypes (e.g. Bacillus, Lysinibacillus, Paenibacillus, Psychrobacillus, Viridibacillus) from raw and pasteurized milk at 6°C. Growth curves were generated by counting total bacterial count and spore count every day for 30 days at 6°C. The obtained data d can serve as the foundation for the development of better tools to predict the shelf life of fluid milk.
The researchers developed a predictive model to investigate the growth of psychrotolerant spore-forming bacteria. Such a model allows the identification of parameters that most effectively can increase the shelf life of fluid milk.
They used a Monte Carlo simulation model to predict the spoilage patterns. The model assumed that the spoilage level for fluid milk is >20,000 cfu/mL. Monte Carlo model predicted that 66% of ½ gallons milk pasteurized at high temperature, for short time would reach the critical level of 20,000 cfu/mL after 21 days of storage at 6°C, in agreement with current spoilage rate.
The parameter that influenced most of the shelf life was the maximum growth rate of psychrotolerant spore-formers. The research showed that different psychrotolerant spore-formers have different abilities to germinate and grow in fluid milk.   Better characterization of the ability to germinate and the growth rates of the diverse of psychrotolerant spore-formers will have the best impact on improving the model.
The second parameter that influences the model is the initial concentration of psychrotolerant spore-formers in the bulk raw tanks.  The model shows that microfiltration can reduce the initial numbers of psychrotolerant spore-formers by 2.2 logs, the shelf life can be extended by 4 days.
The research data indicates that if the numbers of spore-forming bacteria are reduced and if their outgrowth can be controlled, the shelf life of milk can be improved from 2 weeks to a month.  The created model shows that if the milk is kept refrigerated at 40 C, instead of 60 C only 9% of the milk will spoil in 21 days as compared with 66% at the currently used temperature.
To produce high-quality milk with extended shelf life, it is essential to control psychrotolerant spore-formers. The study identifies growth parameters that are required to consistently predict the shelf life of fluid milk due to psychrotolerant spore-formers. Processing decisions and storage of the milk through the supply chain can reduce spoilage due to spore-formers.
The authors emphasize that the model developed provides a new tool for the dairy industry to predict the shelf life of pasteurized milk and extend it. This could allow manufacturers to provide a more meaningful “sell-by-date”. The model demonstrates the effectiveness of predictive modeling for the dairy industry and allows a “what if” analysis to estimate the outcome of different processing procedures.

Tracking and tracing foods- the role of blockchain


Part 2- Blockchain as a solution to traceability

Why Blockchain?

In our previous blog we defined blockchain as a decentralized, distributed ledger technology, among many thousands of computers that can record transactions between parties in a secure and permanent way. It is often associated with cryptocurrency. 
The blockchain is an emerging technology that offers a way for companies to perform transactions with each other securely as they move products around the world. What makes blockchain unique is that it is a shared, permanent ledger that records all the transactions in a chronological order that cannot be altered or deleted. The food supply chain consists of millions of transactions. The transactions need verification that no one has tampered with the data.
One of the first experiment  with blockchain and food safety was initiated by Walmart and a number of other food giants (Unilever, Dole, Nestlé,  Kroger, McCormick and Company, McLane Company, Driscoll’s, Tyson Foods, and Golden State Foods )that  teamed up with IBM to investigate how to utilize blockchain to improve the traceability of food. They used blockchain to trace mangoes from Mexico by tagging pallets of mangoes and tracing them through the food chain.  While manual tracing took almost a week, the software took 2.2 seconds to show the results. Due to the success of these experiments, Walmart is now reaching out to other suppliers and retailers to join their trials.
In the event of a recall, the blockchain technology can provide real-time notifications to everyone throughout the supply chain, effectively reducing the product withdrawal time from weeks to days, even hours. Additionally, blockchain can allow the identification of places along the supply chain where efficiencies can be improved.
A year ago, GS1 announced a collaboration with IBM and Microsoft to leverage their industry standards within future enterprise blockchain applications for their supply chain clients.
There is extensive coverage of blockchain, as it relates to food traceability, by the news. Most of this coverage over hypes blockchain and present it as a simple “light-switch” solution. Just turn the switch on and get the desired results. However, blockchain is a much more complicated and has numerous hurdles to overcome, before becoming a reality in food tracing. It heavily relies on the quality of the traceability data. To get appropriate traceability, it requires having all parties aligned with each other, using the same data standards.
While blockchain holds promise in raising transparency and improving operational efficiencies in the food industry, there are more trials and validation that need to be carried out in real-world application.  The first step is building the foundation of traceability that uses a common language industry-wide.

Current Status of Blockchain

Blockchain is a technology in its infancy. Worldwide there are numerous proof of concepts, and more are being added. However, most are not public Blockchains where all of the information is open and transparent, but rather permission-based blockchains. All are very simple and small-scale experiments.   There must be an acknowledgment of the extensive efforts required for data gathering and data quality, and a traceability program is a key for any blockchain solution to be successful.   Blockchain is not yet a proven solution in the food industry and its main challenge is scaling up beyond the current small-scale experiments.  

Impediments to blockchain adaptation

Blockchain like many emerging technologies creates numerous challenges that have to be resolved before it can achieve mainstream adoption and becomes successful.


Moving from the current status of blockchain that provides concepts and piloting applications to actually deploying productive solutions at the scale required for the food industry, will require further technology development, organizational transformation, and collaboration between all stakeholders. Some blockchain applications have been known to scale poorly.
The blockchain technology could aid in finding the status of a product along the chain. However, it will become more challenging to manage the blockchain as the size of the ledger gets larger.
Some blockchain promoters believe that all the information can be stored on a single chain, similar to Bitcoin, creating a massive unified public record. However, most companies don’t believe in this vision and think that in the foreseeable future permission-based blockchains will prevail.
Tracking the composition of foods that contain 5 or more ingredients is a complex undertaking, acknowledges Frank Yiannas, Walmart’s vice president of food safety. Most food products contain many ingredients.  Therefore, the technology might be only appropriate for simple products such as fruit, raw fish, and meat.

Unified Standards

The development of standards for data formatting, using the same protocols is a prerequisite to the blockchain adaptation. If companies try to create blockchain solutions in isolation the industry will end up with blockchains that do not talk to each other thereby defeating the purpose of the blockchain technology.
For a true trace back, all suppliers need to participate. It is admirable that Walmart had invited some major food companies to participate in their pilot trial of the blockchain.  However, much larger participation is required to make it a standard.  The traceability efforts by FoodLogiQ created FoodLogiQ Connect, a cloud-based supplier transparency, and traceability. FoodLogiQ claims to have captured and tracked more than 10 million traceability events using the state-of-the-art technology platform.
FoodLogiQ is currently working with several industry associations and experts such as the Produce Marketing Association (PMA) and GS1. The purpose is to help define the data standards and requirements that would go into a Blockchain solution.
However, the food industry needs to do more to achieve 100% participation in identical traceability. There is also the question of what impact will it have on the role of the regulatory bodies?

Participation in multiple blockchains

Probably there will not be just a single blockchain-based system in the food industry; instead, there will likely be various private permission-based blockchains due to the competitive nature of the business. Suppliers will have to participate in numerous blockchain networks.
It is imperative that the multiple private blockchains will be capable of inter-connectivity since a single supplier can supply hundreds, if not thousands of different food companies.  It is not practical to add the product data into multiple blockchains.

Energy consumption

The blockchain is not a green technology. The electricity required for one bitcoin trade could power a house for a month. The process of writing new blocks consumes a lot of energy.
Forbes magazine claims that proof of work (POW) is costly and time-consuming to produce but easy for others to verify. The Bitcoin POW mechanism is so expensive that it consumes the same amount of electricity it takes to power a country like Switzerland. Can it ever be successful?

Confidentiality and security

Public blockchain systems raise significant concerns regarding data confidentiality. Additionally, it requires honesty by all participants.
“Are those parties are really who they say they are, or where they say they are, or what they are—it doesn’t do that, and that’s really the flaw with it,” Mitchell Weinberg, who founded the food fraud detection and prevention firm Inscatech says. “There’s just no validation of the information that’s being put in. It’s only as good as the person who’s entering the information.”  “The people who are adulterating the food and doing stuff to it, they’re very sophisticated in terms of concealing their crime,” he says. “Blockchain’s not going to tell you how that food’s being harvested in the field and what’s going into it and whether the people collecting it or consolidating it are adding anything to it.”


Blockchain is an interesting new technology that has the potential to revolutionize the food safety. It can solve critical issues affecting food safety such as tracing foods in case of a recall.  However, it still has many barriers to overcome before it can gain extensive adaptation in food safety. Its current status is such that it can be used to trace a single product along the chain, but it becomes much more challenging for foods that are composed of multiple ingredients. It would be a mistake rushing into blockchain technology without a thorough understanding of how it is likely to be used and what it could accomplish.

Whey contaminated with Salmonella causes a ripple effect


The Ripple Effect

The ripple effect is a chain reaction of recalls. Typically an ingredient manufacturer produces a product that may contain a pathogen. The contaminated product is distributed to many other manufacturers that incorporate the ingredient into their products. As a result of the initial recall, all the users of the ingredient are required to recall their products.  In some cases a tertiary recall happens, when secondary recalled products are manufactured in line adjoined to the lines where the secondary products are produced.
We are currently starting to see the chain reaction as a result of a whey powder recall.

The Whey Powder Recall

The U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS) announced the voluntary recall of whey powder manufactured by New Ulm-based MN Associated Milk Producers, Inc. (AMPI).  The whey powder recall happened after some of the product was distributed to other manufacturers.

Hungry Man TV Dinners

As a result of the whey powder recall, the FSIS announced the recall of some TV meals because the whey powder used in the ranch dressing seasoning had been supplied to the firm by AMPI. The impacted product is 15.25-oz. individual frozen microwavable meals with “HUNGRY MAN CHIPOTLE BBQ SAUCED BONELESS CHICKEN WYNGZ.” These products were shipped to stores in Massachusetts, Pennsylvania, and Virginia.
On July 17, 2018, the whey powder vendor notified Pinnacle Foods, Inc. that the whey powder ingredient which was used in the ranch dressing seasoning supplied to the firm might have been contaminated with Salmonella. The ranch dressing seasoning was incorporated into mashed potatoes and packaged as a component with a boneless chicken dinner. There have been no reports of illnesses due to consumption of these products.

Flowers Foods Swiss Rolls and Captain John Derst’s Old Fashioned Bread

Flowers Foods Inc. of Thomasville, GA recalled Swiss Rolls and Captain John Derst’s Old Fashioned Bread due to concerns of possible salmonella contamination. The Swiss Rolls were sold nationwide under the brand names Mrs. Freshley’s, Food Lion, H-E-B, Baker’s Treat, Market Square, and Great Value. The Captain John Derst’s Old Fashioned Bread was sold in Alabama, Florida, Georgia, North Carolina, and South Carolina. Flowers Foods said that the recall was because the Salmonella might be present in the whey powder used as a major ingredient in these products. The company issues a press release with the relevant information. No illnesses were reported.

Ritz cracker sandwiches and Ritz Bits products

Mondelez International of New Jersey, the manufacturer of Ritz crackers, says that their products contain whey powder, which the whey supplier has recalled because of the salmonella risk.  The recall affects Ritz Bits Cheese, Ritz Cheese Cracker Sandwiches, Ritz Bacon Cracker Sandwiches with Cheese, Ritz Whole Wheat Cracker Sandwiches with White Cheddar Cheese, Ritz Everything Cracker Sandwiches with Cream Cheese, and Mixed Cookie variety. The products have expiration dates of January 14, 2019, to April 13, 2019.
The products were distributed in the United States, including Puerto Rico and the U.S. Virgin Islands. The recall is a precaution, as no complaints of illness have been reported.

Goldfish crackers recalled by Pepperidge Farm 

The latest victim of the contaminated whey powder is Pepperidge Farm, they recalled four types of Goldfish Crackers because there is a chance whey powder used in the seasonings may contain Salmonella. The company said the crackers were sold throughout the country and that no illnesses have been reported. In the coming days and weeks, I expect to see more recalls associated with this recalled whey powder.