The U.S. Food and Drug Administration (FDA) has ruled that the new genetically modified strains of food do not need special labeling (thus many are unknowingly eating genetically modified foods). The FDA currently requires no labeling because it believes that genetically modified foods are not significantly different than hybrids developed by cross breeding.
Genetically modified foods are different, however, from hybrids. Whereas many hybrids are the results of crossing two or more varieties of the same species, genetically modified foods do not need to be. Actually, it is believed to be possible to insert the gene of an animal (or a different species of plant) into a plant in order to make a genetically modified plant, such cannot occur with normal hybrids: "Potatoes may be spliced with chicken genes, tomatoes spliced with fish genes, corn spliced with 'virus' genes, pigs spliced with human genes. Bacteria, insect, and animal combinations and various plant combinations produced. Manufacturers can sell bioengineered foods without [adequate] safety testing or disclosure.
Thursday, July 12, 2007
Tuesday, July 10, 2007
Controversies
Controversies
Safety
-Potential human health impact: allergens, transfer of antibiotic resistance markers, unknown effects
-Potential environmental impact: unintended transfer of transgenes through cross-pollination, unknown effects on other organisms (e.g., soil microbes), and loss of flora and fauna biodiversity
Access and Intellectual Property
-Domination of world food production by a few companies
Increasing dependence on Industralized nations by developing countries
Biopiracy—foreign exploitation of natural resources
Ethics
-Violation of natural organisms' intrinsic values
Tampering with nature by mixing genes among species
Objections to consuming animal genes in plants and vice versa
Stress for animal
Labeling
-Not mandatory in some countries (e.g., United States)
Mixing GM crops with non-GM confounds labeling attempts
Society
-New advances may be skewed to interests of rich countries
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml
Safety
-Potential human health impact: allergens, transfer of antibiotic resistance markers, unknown effects
-Potential environmental impact: unintended transfer of transgenes through cross-pollination, unknown effects on other organisms (e.g., soil microbes), and loss of flora and fauna biodiversity
Access and Intellectual Property
-Domination of world food production by a few companies
Increasing dependence on Industralized nations by developing countries
Biopiracy—foreign exploitation of natural resources
Ethics
-Violation of natural organisms' intrinsic values
Tampering with nature by mixing genes among species
Objections to consuming animal genes in plants and vice versa
Stress for animal
Labeling
-Not mandatory in some countries (e.g., United States)
Mixing GM crops with non-GM confounds labeling attempts
Society
-New advances may be skewed to interests of rich countries
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml
Friday, July 6, 2007
GM food benefits???
Benefits
Crops
-Enhanced taste and quality
-Reduced maturation time
-Increased nutrients, yields, and stress tolerance
-Improved resistance to disease, pests, and herbicides
-New products and growing techniques
Animals
-Increased resistance, productivity, hardiness, and feed efficiency
-Better yields of meat, eggs, and milk
-Improved animal health and diagnostic methods
Environment
"-Friendly" bioherbicides and bioinsecticides
-Conservation of soil, water, and energy
-Bioprocessing for forestry products
-Better natural waste management
-More efficient processing
Society
-Increased food security for growing populations
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml
Tuesday, July 3, 2007
PCR
The analytical methods contain the following steps:
1.- Extraction of DNA:
It is necessary to extract the genetic material free from other impurities which might interfere in further steps of the analysis.
2.-PCR reaction ( Polymerase Chain Reaction)
The PCR reactions are suited to multiply and amplify specific fragments of DNA that are alien genes to the food being analysed.
The primer starter molecules used in the beginning of the reaction decides which sequence of DNA will be multiplied.
To avoid false negative results due to inhibit action of impurities during extraction of the DNA it is important to include a positive reaction.
3.-Making the PCR product visible Through gelelectrophoresis (agarosegelelectrophoresis).
The products of the PCR reaction can be made visible together with the determination of the length of the base pair, the alien gen.
4.-Confirmation of the results
The confirmation of the results are being made by controlling the sequence of the base in the PCR product using specific sequence restriction, hybridization with specific sonde Nested PCR and Sequencing The basic PCR gives only qualitative indications.
To obtain quantitative results the Competitive PCR or the RT-PCR should be used
1.- Extraction of DNA:
It is necessary to extract the genetic material free from other impurities which might interfere in further steps of the analysis.
2.-PCR reaction ( Polymerase Chain Reaction)
The PCR reactions are suited to multiply and amplify specific fragments of DNA that are alien genes to the food being analysed.
The primer starter molecules used in the beginning of the reaction decides which sequence of DNA will be multiplied.
To avoid false negative results due to inhibit action of impurities during extraction of the DNA it is important to include a positive reaction.
3.-Making the PCR product visible Through gelelectrophoresis (agarosegelelectrophoresis).
The products of the PCR reaction can be made visible together with the determination of the length of the base pair, the alien gen.
4.-Confirmation of the results
The confirmation of the results are being made by controlling the sequence of the base in the PCR product using specific sequence restriction, hybridization with specific sonde Nested PCR and Sequencing The basic PCR gives only qualitative indications.
To obtain quantitative results the Competitive PCR or the RT-PCR should be used
Sunday, July 1, 2007
Dna detection method
Western Blot
The method of Western Blot the extraction of the transgenetic protein from the food is done by means of a nitro-cellulose membrane which binds the proteins. The membrane is immersed in a solution of a specific antibody together with an enzyme resulting in a colour reaction. This method is very labour intensive and therefore not being used in routine.
The method of Western Blot the extraction of the transgenetic protein from the food is done by means of a nitro-cellulose membrane which binds the proteins. The membrane is immersed in a solution of a specific antibody together with an enzyme resulting in a colour reaction. This method is very labour intensive and therefore not being used in routine.
Thursday, June 28, 2007
DNA probes
What are DNA Probes?
Little more than a decade ago, toxic phytoplankton monitoring with DNA probes was still in the realm of science fiction. Today it is a reality. Probes for some key micro-algae are already in commercial use and ultimately DNA probes could become a major HAB monitoring tool.
What exactly are they?
DNA probes have been in use for more than a decade in medicine and dentistry, but they have only recently been developed with the aquaculture industry in mind. The DNA of a selected micro-alga is sequenced, and the sequence of nucleotides that makes up its genetic code is compared with that of other related algae using readily available computer software packages. Unique nucleotide "signatures" (usually between 15 and 50 nucleotides) are selected to develop into probes. The ribosomal RNA (rRNA) of the cell is targeted because it is abundant in cells and so good recognition, or a good "hit", is ensured. The probes will have some "tag", for example fluorescein, attached for easy recognition of a positive assay. The probes can be prepared for a number of different assay systems, but require intensive trialling to ensure there is no cross-reactivity with other micro-algae species.
Pseudo-nitzschia and Alexandrium whole cell format DNA probes are now used routinely in New Zealand's phytoplankton monitoring programmes as an aid to risk management decision-making, and the monitoring laboratory (Cawthron Institute) is approved by International Accreditation New Zealand (recognised under ISO17025).
How are they used?
Identification of micro-algae to species level is vital so that shellfish growers, and health and industry officials, can make safe and economically sound harvesting decisions.
Standard phytoplankton monitoring methods involve identifying toxic species in a water sample and counting them. It is labour intensive and requires expert training in the recognition of the critical algae. In some case scanning electron microscope preparation of samples can be required to differentiate species. This can be expensive and cause delays. DNA probes offer an exciting and rapid alternative
http://www.geneprobes.org/whatare.htm
Little more than a decade ago, toxic phytoplankton monitoring with DNA probes was still in the realm of science fiction. Today it is a reality. Probes for some key micro-algae are already in commercial use and ultimately DNA probes could become a major HAB monitoring tool.
What exactly are they?
DNA probes have been in use for more than a decade in medicine and dentistry, but they have only recently been developed with the aquaculture industry in mind. The DNA of a selected micro-alga is sequenced, and the sequence of nucleotides that makes up its genetic code is compared with that of other related algae using readily available computer software packages. Unique nucleotide "signatures" (usually between 15 and 50 nucleotides) are selected to develop into probes. The ribosomal RNA (rRNA) of the cell is targeted because it is abundant in cells and so good recognition, or a good "hit", is ensured. The probes will have some "tag", for example fluorescein, attached for easy recognition of a positive assay. The probes can be prepared for a number of different assay systems, but require intensive trialling to ensure there is no cross-reactivity with other micro-algae species.
Pseudo-nitzschia and Alexandrium whole cell format DNA probes are now used routinely in New Zealand's phytoplankton monitoring programmes as an aid to risk management decision-making, and the monitoring laboratory (Cawthron Institute) is approved by International Accreditation New Zealand (recognised under ISO17025).
How are they used?
Identification of micro-algae to species level is vital so that shellfish growers, and health and industry officials, can make safe and economically sound harvesting decisions.
Standard phytoplankton monitoring methods involve identifying toxic species in a water sample and counting them. It is labour intensive and requires expert training in the recognition of the critical algae. In some case scanning electron microscope preparation of samples can be required to differentiate species. This can be expensive and cause delays. DNA probes offer an exciting and rapid alternative
http://www.geneprobes.org/whatare.htm
Saturday, June 23, 2007
Know more about genetic modified food...
What are Genetically Modified (GM) Foods?
GM is a special set of technologies that alter the genetic makeup of such living organisms as animals, plants, or bacteria. Biotechnology, a more general term, refers to using living organisms or their components, such as enzymes, to make products that include wine, cheese, beer, and yogurt.
Combining genes from different organisms is known as recombinant DNA technology, and the resulting organism is said to be "genetically modified," "genetically engineered," or "transgenic." GM products (current or in the pipeline) include medicines and vaccines, foods and food ingredients, feeds, and fibers.
Locating genes for important traits—such as those conferring insect resistance or desired nutrients—is one of the most limiting steps in the process. However, genome sequencing and discovery programs for hundreds of different organisms are generating detailed maps along with data-analyzing technologies to understand and use them.
History.....
In 2003, about 167 million acres (67.7 million hectares) grown by 7 million farmers in 18 countries were planted with transgenic crops, the principal ones being herbicide- and insecticide-resistant soybeans, corn, cotton, and canola. Other crops grown commercially or field-tested are a sweet potato resistant to a virus that could decimate most of the African harvest, rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries, and a variety of plants able to survive weather extremes.
On the horizon are bananas that produce human vaccines against infectious diseases such as hepatitis B; fish that mature more quickly; fruit and nut trees that yield years earlier, and plants that produce new plastics with unique properties.
In 2003, countries that grew 99% of the global transgenic crops were the United States (63%), Argentina (21%), Canada (6%), Brazil (4%), and China (4%), and South Africa (1%). Although growth is expected to plateau in industrialized countries, it is increasing in developing countries. The next decade will see exponential progress in GM product development as researchers gain increasing and unprecedented access to genomic resources that are applicable to organisms beyond the scope of individual projects.
GM food....effects......
Technologies for genetically modifying (GM) foods offer dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all new technologies, they also poses some risks, both known and unknown. Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation
GM is a special set of technologies that alter the genetic makeup of such living organisms as animals, plants, or bacteria. Biotechnology, a more general term, refers to using living organisms or their components, such as enzymes, to make products that include wine, cheese, beer, and yogurt.
Combining genes from different organisms is known as recombinant DNA technology, and the resulting organism is said to be "genetically modified," "genetically engineered," or "transgenic." GM products (current or in the pipeline) include medicines and vaccines, foods and food ingredients, feeds, and fibers.
Locating genes for important traits—such as those conferring insect resistance or desired nutrients—is one of the most limiting steps in the process. However, genome sequencing and discovery programs for hundreds of different organisms are generating detailed maps along with data-analyzing technologies to understand and use them.
History.....
In 2003, about 167 million acres (67.7 million hectares) grown by 7 million farmers in 18 countries were planted with transgenic crops, the principal ones being herbicide- and insecticide-resistant soybeans, corn, cotton, and canola. Other crops grown commercially or field-tested are a sweet potato resistant to a virus that could decimate most of the African harvest, rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries, and a variety of plants able to survive weather extremes.
On the horizon are bananas that produce human vaccines against infectious diseases such as hepatitis B; fish that mature more quickly; fruit and nut trees that yield years earlier, and plants that produce new plastics with unique properties.
In 2003, countries that grew 99% of the global transgenic crops were the United States (63%), Argentina (21%), Canada (6%), Brazil (4%), and China (4%), and South Africa (1%). Although growth is expected to plateau in industrialized countries, it is increasing in developing countries. The next decade will see exponential progress in GM product development as researchers gain increasing and unprecedented access to genomic resources that are applicable to organisms beyond the scope of individual projects.
GM food....effects......
Technologies for genetically modifying (GM) foods offer dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all new technologies, they also poses some risks, both known and unknown. Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation
Sunday, May 20, 2007
Cooking vs Mircoogansim
Won't cooking kill bacteria?
Cooking food to 160 degrees Fahrenheit will kill most bacteria. Some meats need to be even hotter -- for example, all poultry should reach an internal temperature of 165 degrees. (Don't guess by the color; use a meat thermometer.) But if the food has been at room temperature for more than two hours, bacteria may have accumulated to dangerous levels and formed heat-resistant toxins that cannot be killed by cooking. Even cooked food can become contaminated this way, so get those leftovers into the fridge as soon as you can.
Cooking food to 160 degrees Fahrenheit will kill most bacteria. Some meats need to be even hotter -- for example, all poultry should reach an internal temperature of 165 degrees. (Don't guess by the color; use a meat thermometer.) But if the food has been at room temperature for more than two hours, bacteria may have accumulated to dangerous levels and formed heat-resistant toxins that cannot be killed by cooking. Even cooked food can become contaminated this way, so get those leftovers into the fridge as soon as you can.
Wednesday, April 25, 2007
Importances of HACCP
The Importance of HACCP for the Food Industry
There are a number of reasons why, especially in the food industry, implementation of quality assurance systems, such as HACCP, is an issue of importance:
- Agricultural products are often perishable and subject to rapid decay due to physiological processes and microbiological contamination.
- Most agricultural products are harvested seasonally.
- Products are often heterogeneous with respect to desired quality parameters such as content of important components (e.g. sugars), size and colour. This kind variation is dependent on cultivar differences and seasonal variables, which can not be controlled.
- Primary production of agricultural products is performed by a large number of farms operating on a small scale.
- Despite the progress in medicine, food science and the technology of food production, Illness caused by foodborne pathogens continues to present a major problem in terms of both health and economic significance
- HACCP as an management tool can contribute to increase competitiveness of the Food Industry.
Retrived from:
http://www.umass.edu/ne165/haccp1998/ziggers.html
Wednesday, April 11, 2007
Food Recall
Food Recall is an effective method of removing or correcting consumer products that are in violation of laws adminstated by Food and Drug Adminstration (FDA). Recall is a voluntary action that takes place because manufacturers and distributors carry out their responsibilty to protect the public health and well-being from products that present a risk of injury or gross deception or are otherwise defective.
Recall can be undertaken voluntarily and at any time by manufacturers and distributors, or at request of the FDA. A request by the FDA that a frim recall a product is reserved for urgent situations and is to be directed to the frim that has primary responsibilty for the manufacture and marketing of the product that is to be recalled.
Recall can be undertaken voluntarily and at any time by manufacturers and distributors, or at request of the FDA. A request by the FDA that a frim recall a product is reserved for urgent situations and is to be directed to the frim that has primary responsibilty for the manufacture and marketing of the product that is to be recalled.
Wednesday, April 4, 2007
Food safety
Food is necessary to sustain and for us to enjoy life, however it can also be a medium for transmitting hazards and causing forborne disease and even death. Thus, food safety is very important to for everyone.
Food safety refers to when food is consumed; it should not contain contaminants at harmful level. It involves safety aspects form receiving, storage, production, transportation to consumption. Food safety is a shared responsibility which requires a multi-sectoral effort by governments, food industries and consumers.
Role of government:
~To establish a framework that promotes the delivery of safe food and provides adequate information to consumers.
~To ensures that up-to-date food legislation and properly enforced through inspection and testing programmes.
~To educates consumers on food-borne hazards and how to keep food safe.
Role of food industries:
~ offer safe food to public
~comply with government requirement~ food industry players adopt good agricultural and manufacturing practices to produce safe and wholesome food
~ educate employees on food safety, they also educate consumers in the safe use of products, be they raw, semi-processed or ready-to-eat food.
Role of consumer:
~ equipped yourself with knowledge of food safety risks and safe food practices
~ adopt to safe food handling and preparation practices to protect everyone
Foodborne diseases usually occur as a result of mishandling of food during preparations. Food can be contaminated in many different ways. Some food products may already contain bacteria or parasites. The microbes can be spread during the packaging process if the food products are not handled properly. Failure to cook or store the food properly can cause further contamination. Leaving food at danger zone (5 to 60°C) for more than 2 hours will result in proliferation of microrganism in the food which make it unsafe for consupmtion. Symptoms of foodborne illness vary but usually include gastrointestinal problems. Foodborne illness may be severe and life-threatening, especially in young children, older adults, pregnant women, and persons with weakened immune systems.
Knowing the consequences, it is very important for everyone to practice safe food practice. Below are some recommendation that we can follow to practice food safety.
Recommendations :
References:
http://www.ava.gov.sg/NR/rdonlyres/5BC01CCC-890D-434F-B91C-A1A15E28A2BC/8849/Attach1_KeystoSaferFoodEng.PDF
http://www.ava.gov.sg/FoodSector/FoodSafetyEducation/
Food safety refers to when food is consumed; it should not contain contaminants at harmful level. It involves safety aspects form receiving, storage, production, transportation to consumption. Food safety is a shared responsibility which requires a multi-sectoral effort by governments, food industries and consumers.
Role of government:
~To establish a framework that promotes the delivery of safe food and provides adequate information to consumers.
~To ensures that up-to-date food legislation and properly enforced through inspection and testing programmes.
~To educates consumers on food-borne hazards and how to keep food safe.
Role of food industries:
~ offer safe food to public
~comply with government requirement~ food industry players adopt good agricultural and manufacturing practices to produce safe and wholesome food
~ educate employees on food safety, they also educate consumers in the safe use of products, be they raw, semi-processed or ready-to-eat food.
Role of consumer:
~ equipped yourself with knowledge of food safety risks and safe food practices
~ adopt to safe food handling and preparation practices to protect everyone
Foodborne diseases usually occur as a result of mishandling of food during preparations. Food can be contaminated in many different ways. Some food products may already contain bacteria or parasites. The microbes can be spread during the packaging process if the food products are not handled properly. Failure to cook or store the food properly can cause further contamination. Leaving food at danger zone (5 to 60°C) for more than 2 hours will result in proliferation of microrganism in the food which make it unsafe for consupmtion. Symptoms of foodborne illness vary but usually include gastrointestinal problems. Foodborne illness may be severe and life-threatening, especially in young children, older adults, pregnant women, and persons with weakened immune systems.
Knowing the consequences, it is very important for everyone to practice safe food practice. Below are some recommendation that we can follow to practice food safety.
Recommendations :
- Wash your hands thoroughly before and after handling any food.
- Wash your hands thoroughly after using the bathroom, changing diapers.
- Wash your hands after coming into contact with animals.
- Wash all cutting boards and utensils with hot water and soap after preparing each food item and prior to moving on to the next food item.
- Wear gloves or avoid preparation if your hands have any cuts or sores.
- Avoid cross-contaminating food items -- separate meat, poultry and seafood from other food and always wash hands, utensils and boards after coming into contact with these products.
- Cook to proper temperatures. Cook eggs until both the white and yolk are firm. Fish should be opaque and flake easily. Red meats and poultry should reach an internal temperature of 160 and 180 degrees, respectively. Leftovers must be reheated thoroughly to at least 165 degrees Fahrenheit.
- Refrigerate promptly -- some items such as meat and poultry must be frozen if not to be used within 1-2 days. Leftovers should be refrigerated within two hours. Keep frozen foods in the freezer until they are ready to be thawed and cooked.
- Foods can also be contaminated before they are purchased. Watch for and do not use outdated food, packaged food with the seal broken, and cans that have a bulge. Do not use foods that have an unusual odor or a spoiled taste.
- Prepare home-canned foods in nearly sterile conditions and with extreme caution. Home-canned food is the most common cause of botulism.
References:
http://www.ava.gov.sg/NR/rdonlyres/5BC01CCC-890D-434F-B91C-A1A15E28A2BC/8849/Attach1_KeystoSaferFoodEng.PDF
http://www.ava.gov.sg/FoodSector/FoodSafetyEducation/
Monday, April 2, 2007
Some example of hazard in food production.
Biological:
-Macrobiological - Flies & Cockroaches
-Microbiological - Bacterial, Fungus, Viruses, Microscopic Parasitic, Algae
-Pathogens are common to all foods, they originate in the gut of mammals and carried on food and by people and animals.
Physical:
-Glass, Wood, Stones, Sticks, Insects, Plastic, Jewellery
-Chemical
-Mycotoxins (example aflatoxins)
-Agricultural
-Heavy Metals
-Food Additives
-Sabotage
Preventives measures:How do we control these Pathogens?
Over time, Temperature, Nutrition, AcidityStaff TrainingPest ControlUsing HACCP
Pre-requisites?
The elements involved in building a HACCP food safety system (Pre-requisites)
Calibration - Equipment involved in food safety or quality, example - scales, coolrooms, freezers, cooking equipment that requires calibrating to achieve operating consistency.
Cleaning - A cleaning schedule must be developed and documented to reflect the company’s attitude towards cleanliness.
Approved Suppliers - An approved supplier programme must be implemented to achieve safe & consistent quality of raw materials being received at the premises. This means that to avoid purchasing possibly contaminated food, packaging, cleaning chemicals or ingredients we must use suppliers that meet our specifications and have an appropriate food safety system in place, if we choose not to use approved suppliers then we may be liable in the event of a food poisoning outbreak.
Training - All persons in the employ of your business that have an impact on food safety or quality must be trained, and this training must be documented.
GMP/GHP - (Good Manufacturing Practises / Good Hygiene Practises) All persons in the employ of your business must receive training in hygiene, cleaning and the approved method of carrying out tasks that may be a risk to product integrity e.g poor handling or contamination
Research retrieved from: http://www.haccpfoodsafety.net.au/
Biological:
-Macrobiological - Flies & Cockroaches
-Microbiological - Bacterial, Fungus, Viruses, Microscopic Parasitic, Algae
-Pathogens are common to all foods, they originate in the gut of mammals and carried on food and by people and animals.
Physical:
-Glass, Wood, Stones, Sticks, Insects, Plastic, Jewellery
-Chemical
-Mycotoxins (example aflatoxins)
-Agricultural
-Heavy Metals
-Food Additives
-Sabotage
Preventives measures:How do we control these Pathogens?
Over time, Temperature, Nutrition, AcidityStaff TrainingPest ControlUsing HACCP
Pre-requisites?
The elements involved in building a HACCP food safety system (Pre-requisites)
Calibration - Equipment involved in food safety or quality, example - scales, coolrooms, freezers, cooking equipment that requires calibrating to achieve operating consistency.
Cleaning - A cleaning schedule must be developed and documented to reflect the company’s attitude towards cleanliness.
Approved Suppliers - An approved supplier programme must be implemented to achieve safe & consistent quality of raw materials being received at the premises. This means that to avoid purchasing possibly contaminated food, packaging, cleaning chemicals or ingredients we must use suppliers that meet our specifications and have an appropriate food safety system in place, if we choose not to use approved suppliers then we may be liable in the event of a food poisoning outbreak.
Training - All persons in the employ of your business that have an impact on food safety or quality must be trained, and this training must be documented.
GMP/GHP - (Good Manufacturing Practises / Good Hygiene Practises) All persons in the employ of your business must receive training in hygiene, cleaning and the approved method of carrying out tasks that may be a risk to product integrity e.g poor handling or contamination
Research retrieved from: http://www.haccpfoodsafety.net.au/
Saturday, March 31, 2007
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