Cursos y Diplomados Inocuidad Alimentaria

Cursos y Diplomados Inocuidad Alimentaria

jueves, 3 de septiembre de 2015

Transgénicos para mejoramiento nutricional de alimentos

Uno de los problemas es la introducción de alérgenos en alimentos inocuos.
La calidad nutricional de algunas legumbres es deficiente en algunos aminoácidos que son esenciales para nuestra nutrición, como por ejemplo la Metionina. Para poder mejorar el balance de aminoácidos en algunos cultivos, es necesario la cruza de plantas con las características deseadas, sin embargo, esta cruza de plantas podría afectar el rendimiento o la calidad de los granos. A través de la ingeniería genética se ha permitido el traspaso o clonación de genes completos desde una especie a otra, lo que resulta en la transcripción de proteínas que podrían actuar como alérgenos. La FDA solicita que todos los alimentos transgénicos consideren el potencial alérgeno de la proteína que ha sido incorporada. Si hay información insuficiente que demuestre que la proteína incorporada podría o no causar una reacción alérgica en la población susceptible, el alimento debe alertar a los consumidores de este hecho.
Un ejemplo de alimento que es nutricionalmente deficiente en aminoácidos como metionina es el frijol de soya, que hoy gracias a las nuevas dietas vegetarianas está siendo ampliamente usado. Al contrario, la nuez brasileña, es un alimento rico en aminoácidos como metionina. La proteína 2S- albúmina de la nuez brasileña contiene un 18% de metionina, lo que convierte al gen que codifica para esta proteína en un candidato para mejorar la calidad nutricional de algunos alimentos. El problema se presenta cuando se evalúa el potencial alérgeno de la proteína 2S – albumina de la nuez brasileña expresada en el frijol de soya es capaz de generar la misma alergia en individuos alérgicos a la nuez brasileña.   
Los resultados de esta evaluación de alergenicidad muestran que la proteína 2S – albúmina expresada en frijol de soya es tan alérgena como la expresada en la nuez brasileña, por lo que este alimento no debiese ser comercializado sin el etiquetado de advertencia. Como controles se evaluó la alergenicidad de la soya no transgénica, y esta no generó alergenicidad en el grupo de riesgo.
Como conclusión se determina que es necesario asegurar la alergenicidad de proteínas en alimentos transgénicos, sobre todo si esas proteínas son provenientes de alimentos con riesgo de alergia.

Fuente: N Engl J Med. 1996 Mar 14;334(11):688-92. Identification of a Brazil-nut allergen in transgenic soybeans. Nordlee JA1, Taylor SL, Townsend JA, Thomas LA, Bush RK.

Aporte: Pamela Aravena E.

martes, 18 de agosto de 2015

Swedish investigation finds risk of contaminated spices in other countries

An outbreak investigation into spices sickened 178 people in Sweden has revealed a risk of contaminated products on the market in other countries.
The first case was reported on 24 December 2014 and the latest count includes data up to 31 July. More than half of the patients (113) fell ill after eating at a restaurant linked to using Iwi spice mix sold by the company Dimpex .

Another firm, Sevan, issued a withdrawal after Salmonella found in some of its already opened products but it is not part of the restaurant outbreak.
 Each year, around two to five cases with Salmonella Enteritidis phage type (PT) 13a are reported.

In 2014, four of the domestic S. Enteritidis cases were PT 13a, according to the research in Eurosurveillance. Minor increase could go unnoticed Sweden launched an ‘urgent inquiry’ in the Epidemic Intelligence Information System (EPIS), on 2 April. No other country has reported an increase of this specific subtype of S. Enteritidis. However, many European Union Member States only subtype S. Enteritidis in outbreak situations or cluster investigations and phage typing or MLVA is not frequent in all EU countries so a minor increase could go unnoticed.

A Rapid Alert System for Food and Feed (RASFF) alert by Austria on 26 June reported Salmonella spp. in a spice mix/seasoning from a manufacturer in Croatia, with a similar content of dried vegetables as one of the brands implicated in the Swedish outbreak. The specific batch from which Salmonella spp. was not available in Sweden. The serotype was S. Oranienburg (not S. Enteritidis PT 13a), according to the Austrian Salmonella Reference Centre. In countries with a high number of reported cases of S. Enteritidis infection, however, a small increase in number of cases with the outbreak strain could go undetected. 

The detection of Salmonella spp. in two different brands of spice mixes sold in Sweden and the RASFF alert from Austria during the outbreak period, however, indicates that there could be a common ingredient in these mixes that are contaminated with Salmonella spp.
Swedish investigation Initial investigations suggested the vehicle of infection was most likely a food item with a long shelf life given the first case was in December. By the end of May, cases increased to 48 and were from over 14 counties. At the beginning of June, Kalmar county reported a case who had fallen ill after eating at a restaurant, cases continued to be reported and at the end of the following week six people were ill. As they all shared the strain, S. Enteritidis PT 13a. In total, 108 cases were connected to the restaurant, including staff members. Many had severe symptoms, including bacteremia, and were hospitalized but exact numbers are not yet known.

Culture analysis require dilution steps and number of replicates were often necessary to detect and isolate Salmonella spp., indicating very low concentration of the pathogen in spices.

Source: Eurosurveillance, Volume 20, Issue 30, 30 July 2015 “Outbreak of Salmonella Enteritidis phage type 13A infection in Sweden linked to imported dried­ vegetable spice mixes, 

Listeria traced to fish products despite passing tests.

Track and trace four people sickened by Listeria monocytogenes linked to a fish producer in Denmark but authorities have not found high levels of the pathogen in products on the market.
The Danish Veterinary and Food Administration said intensive sampling and testing for Listeria at Hjerting Laks has not revealed any products with elevated levels. There has been no product recall because tested samples have been below the accepted limit.

DVFA report traced to Hjerting Laks as it has a DNA match between samples from the company and patients. This information was confirmed through whole genome sequencing. This gives us an excellent opportunity to find sources of outbreaks. In this case, we have a DNA match between Listeria from the patients and samples taken from the company’s production area and equipment. The specific Listeria monocytogenes ST6 sequence pattern in question is not present in other samples from other sources.

In May, FQN reported two people with the same Listeria strain, which caused 40 cases and 16 deaths last year due to consumption of contaminated deli meat.
The current outbreak involves Listeria monocytogenes ST6 and is not linked to the outbreak last year. However, one case of the five mentioned is part of the outbreak traced back to the establishment Hjerting Laks thanks to work by DVFA, Statens Serum Institut and the National Food Institute. The first person became ill at the beginning of April, the second in mid-May, the third in mid-June and the fourth at the end of June. Hjerting Laks response and past outbreak DVFA said it did not know exactly which food item caused the outbreak but suspects smoked salmon, since patients have eaten this product prior to illness.

Hjerting Laks said samples this year of final products have met all requirements; the pathogen could originate from raw materials delivered to other processors and the link to it despite the small case number. The firm previously linked with a minor outbreak of Listeria, late last year, related to smoked halibut, which declined by changing some of the production processes. No further cases related to smoked halibut were reported since November 2014. Officials said due to the incident last year DVFA has strengthened control of Listeria at the company, which co­operated throughout the process. The company change its routines about production and own check scheme. This includes upscaling their analyses program. The establishment implemented tightened supervision for the time being and until we know if the new procedures in place are effective.

Consumers should to throw away products that have exceeded the “use by” date. Also they be careful to keep the refrigerator temperature below 5ºC. Consumers should also remember that a product’s shelf life shortens after package opening. Consumers must also follow the general advices on good hygiene in the kitchen.
In Denmark about 50 cases of illness due to Listeria pathogen are registered a year. However, in 2009 and 2014 there were 90 to 100 due to major outbreaks.


lunes, 17 de agosto de 2015

Public Health Agency Canada investigating 67 illnesses linked to raw oysters.

Consumer’s should eat right away after cooking and refrigerate leftovers.
 The Public Health Agency of Canada (PHAC) is investigating 67 Canadian cases of Vibrio parahaemolyticus (Vp) infections linked to raw shellfish. The majority of illnesses are connected to eating raw oysters.
PHAC said work is ongoing to determine the source and distribution of products and illnesses are avoided if shellfish are cooked before being eaten. British Columbia and Alberta affected. Sixty seven cases were reported in British Columbia (48) and Alberta (19) with one person being hospitalized. Individuals became sick between June 1 and August 7 and all reported consumption of raw shellfish, primarily oysters.

The Canadian Food Inspection Agency and the Department of Fisheries and Oceans and Health Canada are also investigating. Fisheries and Oceans Canada said Vibrio parahaemolyticus is a naturally occurring bacterium that can be present in bivalve shellfish (i.e. clams, oysters, scallops, mussels, cockles) even in harvest areas that are open and approved for shellfish harvesting.

The pathogen is present in higher concentrations in summer months when water and air temperatures rise, increasing risk of infection and illness when bivalve shellfish (like oysters) are consumed raw or undercooked.

Symptoms of infection may include watery diarrhoea, stomach cramps, nausea, vomiting, fever, and headache and usually start within 12 to 24 hours and may last up to three days. 
To reduce the risk of illness, bivalve shellfish should be harvested at the water's edge when the tide is going out and shellfish should be iced, refrigerated or frozen immediately.

Consumer’s should eat right away after cooking, refrigerate leftovers, and always keep raw and cooked shellfish separate. Cooked to a safe internal temperature of 74°C (165°F).

The BC Centre for Disease Control (BCCDC)report an increasing number of shellfish ­related illness occurred this summer with 35 cases reported in June and July. The majority of illnesses were due to raw oysters sourced in British Columbia and served in restaurants, but there have also been some cases associated with raw oysters bought at retail or self-­ harvested. Marsha Taylor.


sábado, 15 de agosto de 2015

Alto contenido de proteínas de la Cutícula del huevo lo protege de la Salmonellosis.

La edad de las gallinas influye directamente en la calidad de la cutícula.
Investigadores de la universidad de Granada han determinado que la composición química de la cutícula del huevo de gallina es un factor “determinante” contra la contaminación de este producto por Salmonella, patógeno bacteriano que con frecuencia produce gastroenteritis.  

Según ha informado investigadores de la Fundación Descubre, la eficacia de esta protección está determinada por la composición de la cutícula, rica en polisacáridos (azúcares), lípidos y proteínas. Estas últimas desempeñan un papel fundamental, ya que una mayor cantidad de proteínas aumenta la protección del huevo frente a la infección bacteriana.

Uno de los factores que influyen en la composición de la cutícula es la edad de las gallinas y los científicos han comprobado que los huevos de las más jóvenes – 25 semanas- tienen una cutícula de mejor calidad (mayor presencia de proteínas), que las mayores con una edad entre 35 y 52 semanas. Para esta investigación han sido utilizadas técnicas analíticas avanzadas como espectroscopia de infrarrojos o electrónica de barrido de las que se ha obtenido información detallada sobre las propiedades de la cutícula.

La madurez de la cutícula (capa formada por proteínas, lípidos y otros componentes que rodea la cascara), la edad de las gallinas o la fecha de la puesta de huevos son otros aspectos que influyen en el proceso de contaminación con la bacteria.
La cutícula, invisible al ojo humano, actúa como una pantalla protectora para el huevo. La cascara es una estructura permeable, con poros; a través de los cuales pueden pasar no solo el agua y oxigeno que el embrión necesita para crecer, sino también bacterias como Salmonella.

El investigador Alejandro Rodríguez, ha explicado que estas proteínas se encargan de regular la permeabilidad de la cutícula; de modo que a mayor proporción menos pasa a través de la cascara del huevo; y por tanto, menos riesgo de que las bacterias puedan proliferar al interior del alimento. Por el contrario una menor cantidad de proteínas significa que la cutícula es más permeable y el agua y las bacterias pueden entrar con más facilidad.

Según los expertos del Departamento de Mineralogía y Petrología, los resultados de este estudio, que aporta información detallada sobre las características de esta cubierta y las funciones de sus componentes, pueden tener aplicaciones relevantes en la industria avícola para empresas relacionadas con la producción de huevos o la selección de gallinas ponedoras.

Aporte: Claudia Soto Peña y Beatriz Villarreal

martes, 4 de agosto de 2015

Cyclospora cases pass 350 in US with some linked to Mexican cilantro

Conditions at multiple firms included human feces and toilet paper found in growing fields and around facilities.
CDC reported more than 350 people in 26 states sickened by Cyclospora cayetanensis. The agency said 358 people are ill with most (199; 56%) reporting onset of illness on or after May 1, and no international travel. Clusters of illness linked to restaurants or events have been reported in Texas, Wisconsin, and Georgia. Investigations in Wisconsin and Texas have preliminarily identified cilantro as a suspect vehicle.  Previous outbreaks of cyclosporiasis were linked to imported fresh produce, including cilantro from the Puebla region of Mexico.
Annually recurring outbreaks (in 2013 and 2014) have been associated with fresh cilantro from the state of Puebla. Fresh cilantro checked at border by FDA issued an import alert to detain samples of fresh cilantro from Puebla from 1 April to 31 August. It comes after the FDA, the government of Mexico’s National Agro­Alimentary Health, Safety and Quality Service (SENASICA) and Federal Commission for the Protection from Sanitary Risks (COFEPRIS), investigated farms and packinghouses. These agencies inspected 11 farms and packing houses that produce cilantro in Puebla from 2013 to 2015, five linked to past C. cayetanensis illnesses, and found objectionable conditions at eight of them, including all five linked through traceback to the illnesses.
Conditions at multiple firms included human feces and toilet paper found in growing fields and around facilities; inadequately maintained and supplied toilet and hand washing facilities or lack of them and water used for washing cilantro vulnerable to contamination from sewage/septic systems.
Shipments of fresh cilantro from other states in Mexico are accepted if they were harvested and packed outside of Puebla. Public Health England (PHE) has also warned of an outbreak linked to contaminated food in Mexico. 24 cases were reported in England and Scotland in June and July, of which 21 were associated with travel to Mexico, it said. Salmonella investigations.
Meanwhile, the outbreak of Salmonella linked to pork products has grown to 90 cases in Washington State. Health officials have asked the CDC to send a special team to help with the investigation. The US Department of Agriculture’s Food Safety and Inspection Service (USDA-­FSIS) issued a public health alert due to concerns about illnesses caused by Salmonella associated with pork products, specifically whole pigs used for pig roasts. FSIS was told of Salmonella I 4, [5],12:i­illness clusters on July 15 and suspects there is a link between the illnesses associated with whole pigs used for pig roasts and eight illness clusters based on information gathered with the Washington State Department of Health and the CDC.

Heavy rains increase the risk of food contamination by Salmonella

Study: Salmonella Infections Rise With Extreme Weather Events

Salmonella is the one of the most common pathogen causing gastroenteritis in humans. The disease can happen when people consume contaminated food such as meat, eggs, produce, among others. Salmonella infections proliferate during seasons characterized by elevated temperatures and precipitation which can amplify bacterial replication and transmission to surface water and food crops (potential sources of infection).

Heavy rains increase the risk of food contamination by Salmonella. For example,   rivers overflows and that excess of water is poured on crops. Sometimes, farmers use chicken manure as fertilizer, therefore, when the precipitation increase, the rain spread the pathogen. Researchers at the University of Maryland has shown that climate change may be causing more than just an increase in extreme weather events such as heat waves and storms. Those events also seem to be bringing a heightened risk of Salmonella outbreaks. The research, published in Environment International, concluded that the risk of salmonellosis can increase in 4,1% when the temperature increase in one unit. They observed that this risk increase was more pronounced in coastal versus non-coastal areas (5.1% vs 1.5%). 
Likewise, they observed a 5.6% increase in salmonellosis risk associated with a 1 unit increase in extreme precipitation events, with the impact disproportionately felt in coastal areas (7.1% vs 3.6%). It is important to considerate that bacteria tend to multiply and grow better in warmer and wetter environments.
In addition, Tirado et al. described that infection with Salmonella Enteritidis appears to be more sensitive to the effects of environmental temperature, at least as compared with infections caused by Salmonella Typhimurium. Inappropriate storage temperature and food handling would be important factors in disease transmission.

-       Group foods together in the freezer—this ‘igloo’ effect helps the food stay cold longer.
-       Keep a few days’ worth of ready-to-eat foods that do not require cooking or cooling.
-       Keep the refrigerator and freezer doors closed as much as possible. A refrigerator will keep food cold for about 4 hours if the door is kept closed. A full freezer will hold its temperature for about 48 hours (24 hours if half-full).
-       Place meat and poultry to one side of the freezer or on a tray to prevent cross contamination of thawing juices.

Aporte: Rosita Cabrera Tagle


lunes, 27 de julio de 2015

World Health Day 2015: From farm to plate, make food safe

Over 40% people suffering from enteric diseases caused by contaminated food were children aged under 5 years.
 New data on the harm caused by foodborne illnesses underscore the global threats posed by unsafe foods, and the need for coordinated, cross-border action across the entire food supply chain, according to WHO, which next week is dedicating its annual World Health Day to the issue of food safety.
World Health Day will be celebrated on 7 April, with WHO highlighting the challenges and opportunities associated with food safety under the slogan “From farm to plate, make food safe.”
Food production has been industrialized and its trade and distribution have been globalized. These changes introduce multiple new opportunities for food to become contaminated with harmful bacteria, viruses, parasites, or chemicals.
Unsafe food can contain harmful bacteria, viruses, parasites or chemical substances, and cause more than 200 diseases - ranging from diarrhoea to cancers. Examples of unsafe food include undercooked foods of animal origin, fruits and vegetables contaminated with feces, and shellfish containing marine biotoxins.
Today, WHO is issuing the first findings from what is a broader ongoing analysis of the global burden of foodborne diseases. The full results of this research, being undertaken by WHO’s Foodborne Disease Burden Epidemiology Reference Group (FERG), are expected to be released in October 2015.
Some important results are related to enteric infections caused by viruses, bacteria and protozoa that enter the body by ingestion of contaminated food. The initial FERG figures, from 2010, show that:

·         There were an estimated 582 million cases of 22 different foodborne enteric diseases and 351 000 associated deaths;
·         The enteric disease agents responsible for most deaths were Salmonella Typhi(52 000 deaths), enteropathogenic E. coli (37 000) and norovirus (35 000);
·         The African region recorded the highest disease burden for enteric foodborne disease, followed by South-East Asia;
·         Over 40% people suffering from enteric diseases caused by contaminated food were children aged under 5 years.
WHO is working to ensure access to adequate, safe, nutritious food for everyone. The Organization supports countries to prevent, detect and respond to foodborne disease outbreaks—in line with the Codex Alimentarius, a collection of international food standards, guidelines and codes of practice covering all the main foods.
Food safety is a cross-cutting issue and shared responsibility that requires participation of non-public health sectors (i.e. agriculture, trade and commerce, environment, tourism) and support of major international and regional agencies and organizations active in the fields of food, emergency aid, and education.


jueves, 23 de julio de 2015

FDA finds tennis rackets used at sprout farm linked to E.coli illnesses.

Seven persons infected with the outbreak strain E.coli O121
 The US Food and Drug Administration (FDA) has found tennis rackets being used to scoop mung bean sprouts onto the conveyor belt during inspections at a facility linked to an outbreak of E.coli O121 which has sickened 17 people.
The agency said two employees were seen using tennis rackets with scratches, chips, frayed plastic, and sponge ­type handles to scoop the sprouts from the water in the harvester onto the belt, which fed them into finished product storage bins.

The same rackets were used the following day in the bubbler during alfalfa sprout harvesting. FDA inspection findings FDA conducted three inspections of Evergreen Fresh Sprouts on May 22­23, May 27­30, and June 6. It is investigating a multi­state outbreak of E. coli O121 infections linked to eating raw clover sprouts from Evergreen Fresh Sprouts, of Moyie Springs, Idaho.

A FDA spokesman told that the product samples taken did not yield the shiga toxin producing E. coli (STEC) bacteria that caused the outbreak. "However, microbial contamination in food is not expected to be uniform but rather clustered and localized. In other words, one can test a portion from a large batch and find it to be negative, but this does not mean we can conclude that the rest of the batch is not contaminated," he said.

Although the samples tested by the FDA did not yield the pathogen that caused the outbreak, this does not necessarily, mean that there was no contamination present. He added there is strong epidemiology and traceback evidence connecting Evergreen raw clover sprouts to this outbreak.

Evergreen Fresh Sprouts had ceased the production of clover sprouts, but mung bean sprouts and alfalfa sprouts were still being produced. 17 persons infected with the outbreak strain of Shiga toxin­ producing E.coliO121 (STEC O121) have been reported from five states, in the June 9 update from the Centers for Disease Control and Prevention (CDC).
The number of people sickened by state is: Idaho (3), Michigan (1), Montana (2), Utah (1), and Washington (10). 47% of ill persons were hospitalized but none have developed hemolytic uremic syndrome (HUS) or died.

FDA investigators observed condensate and irrigation water dripping from rusty valves into sprouting vats containing growing sprouts and a rusty and corroded mung bean room watering system. They also found a pitchfork with corroded metal used to transfer mung bean sprouts into plastic tubs during harvest; and a squeegee with visible corroded metal and non-treated wood also used to agitate mung bean seeds inside a soak vat.

Traceback investigation: Epidemiology and traceback investigations indicated that contaminated raw clover sprouts produced by Evergreen Fresh Sprouts are the likely source of the outbreak. Illness dates range from May 1, to May 20, the age of those affected ranges from 11 to 45 years, with a median of 27 years and seventy­-six percent of ill persons were female.

Source: Food Quality News

martes, 21 de julio de 2015

Sweden investigates Salmonella from spices outbreak

Serbia was the origin for one of the spice mix brands.

Track and trace More than 150 people have been sickened by Salmonella in Sweden with authorities linking the illnesses to spice mix. The Swedish public health agency said 153 people have been reported in the outbreak of Salmonella Enteritidis due to comsuption spice mix (Allkrydda) and some had been hospitalized.

The agency said it is normally difficult to find the source of an outbreak but its suspicions that the cause was a food with a long shelf life and widespread distribution. It added more spices links to the national Salmonella outbreak as several brands could have the same origin. Salmonella Enteritidis, phage type 13a is relatively rare with three to five cases normally reported each year.

Restaurant case peak. More than half of the patients (95) fell ill after eating at a restaurant on Öland which has been linked to Iwi Allkrydda sold by the company Dimpex. The result was the same Salmonella in spice in the patients who become sick due to restaurant food, as well as that from other victims of the nationwide outbreak.

Another manufacturer, Sevan, issued a withdrawal after an illness of Salmonella was linked to its products but it is not part of the restaurant outbreak. The firm has recalled all its Allkrydda sold since October 2014 as a precaution. This covers Sevan Allkrydda 900g with barcode 7331217881469, 450g with barcode 7331217881452 and Bucket 5 kg with EAN code 7331217010708.

Widespread investigation, performed by the Swedish food agency, said the incident is spread across the country. It added the usual method of interviewing victims to identify the suspect food worked less well in this case so investigators needed to test food for many different types to find the cause of the disease.

Serbia was the origin for one of the spice mix brands, according to the RASFF portal. In a normal year about 3,000 Swedes are infected with Salmonella, including around a quarter infected in the country.

Source: Food Quality