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Showing posts from September, 2020

What Is Food Fermentation? (Definition And Processes Of Fermentation)

Fermented foods may be defined as those foods, which have been subjected to the actions of microorganisms or enzymes so that desirable biochemical changes cause significant modification to the food.
By fermentation, food may be made more digestible, nutritious and safer or have better flavour.
The class of fermented food produced in different regions of the world reflect the diet of that region and also the available raw material.

What are the reasons for fermenting foods?(1) Improvement of digestibility: Digestibility, which is measured through different parameters, is generally improved through fermentation.
The enzymes of the fermenting microorganism hydrolyze the complex constituents of the starting material.
(2) Fermentation almost invariably adds flavour to the food: In some cases, the flavour of a partial product is improved directly.
In some other cases, they can be used to make tasty food from different plant product.
(3) To improve the appearance of food: food like Angkak (oriented…

What Are Hemagglutinins? (Meaning Of Hemagglutinin)

Hemagglutinin and Neuraminidase (Hemagglutinin Influenza)Hemagglutinins are proteins that have the ability to agglutinate red blood cells (RBC) in a way similar to antibodies.
Moreover, like antibodies, they act in high dilution on one kind of erythrocytes and not at all or only weakly on another.
Each specific hemagglutinin is therefore clearly different from all other and must be studied individually, the results obtained with one kind cannot be applied to another without verification.
Also, the chemical compositions of different hemagglutinins have often been classified as globulins because their electrophoretic mobility is similar to that of human serum globulin, although most do not require the presence of neutral salts for solubilization.
Also Read: Tannins
Hemagglutinins have been found mostly in plants.
Because of the specificity of their action on red blood cells from different animals.
Boyd and Shapleigh have proposed the term lectins from the latin word legere, which means 't…

Meaning Of Oxalates And Oxalic Acids (An Overview)

Oxalates and Oxalic AcidsOxalates are toxins found in plants such as rhubarb in the form of soluble sodium, potassium salts or insoluble calcium salts that may result to human poisoning and kidney stones when consumed in large quantities.
Oxalates have long been known to occur in nearly all form of living matter, certain families and species of plants contain relatively large amount of this substance, mainly as soluble sodium, potassium salts or insoluble calcium salts.
The name 'oxalates' was coined from its occurrence in plant oxalis (wood sorrel).
The earliest interest in the toxicity of oxalates arose because of severe human poisoning by oxalates following the consumption of large quantities of the leaves of rhubarb known to contain relatively large amounts of oxalates.
Accidental ingestion of oxalic acid as a pure chemical was also known to produce severe corrosive and other toxic effects;
Hence, the conclusion was drawn that the acute poisoning effects of ingesting high oxal…

What Is Tannin? (Meaning And Types Of Tannins)

Tannins are food toxins made up of complex phenolic polymers which are classified into two structural groups which are hydrolyzable tannins and condensed tannins. Tannins are brownish or yellowish substance found in fruits used in making wine.Condensed Tannins are far more common in non-grain starch staples and usually exist in the plant tissues as leuco-anthocyanins or proanthocyanidins.
Condensed tannins have been identified in cassava tubers, in the green pulp of many banana varieties and in yam species.
Tannins binds to both proteins and carbohydrates which has several implications for commodities containing tannins.
The presence of tannins can cause browning or other pigmentation problems in both fresh food and processed products.
Tannins can also act as anti-nutritional factor in two different ways.
Tannins can provoke an astringent reaction in the mouth and make the food unpalatable.
Tannins can also complex with and precipitate proteins in the gut, reducing the digestibility or inhib…

Escherichia Coli (Symptoms, Incubation Period And Prevention)

Escherichia coli is a gram negative, invasive and toxigenic coliform bacterium. Escherichia coli produces endotoxins and in large numbers produce poisoning after cell autolysis.In 1993, the quality and safety of the food industry in the United States was questioned when Escherichia coli serotype 0157:H7 from uncooked beef caused 475 cases of food poisoning and the death of three children.These incidents have meant that food safety was jeopardized and more critical testing, monitoring and inspection are now being put in place to take care of these new manifestations of food borne diseases.Foods such as cold meats, salads, fish, hamburgers, raw foods are prone to escherichia coli contamination.Escherichia coli infection can be spread through the contamination of cooked foods by raw foods, poorly cooked hamburgers, non potent waters, contamination by food handlers.Escherichia coli incubates between 8 to 18 hours with diarrhoea and vomiting as symptoms.Escherichia coli food poisoning can b…

Clostridium Perfrigens (Signs, Symptoms, Incubation Period And Prevention)

Clostridium Perfrigens
Clostridium perfrigens also known as Clostridium welchi is a gram positive, spore-forming, anaerobic bacterium that produces live cell intoxication since the poisoning is always associated with the consumption of large numbers of viable cells.

Because of this characteristic, Clostridium perfrigens poisoning may be confused for an infective type aliment but for the fact that the organism also produces an exotoxin.
In typical incidents, the foods had been heated and then kept in warm atmosphere for several hours, during which time, the cells multiply to infective numbers producing toxins.
Of the five strains of Clostridium perfrigens (A, B, C, D and E), only types A, B and C have been implicated in the disease.
The molecular weight of the toxin is between 32,000 and 40,000 daltons.
The virulence of Clostridium perfrigens is attributable to exotoxins and other hemolytic factors which are most probably lecithinases.
Clostridium perfrigens poisoning is characterized by seve…

Salmonella (Signs, Symptoms And Causes)

Most species of the genus Salmonella are associated with either a septicemic disease or enteric fever.
Salmonella organisms have long been of medical interest because of the ability of some species to produce generalized infection.
These species include Salmonella typhi, Salmonella paratyphi, Salmonella heraschfeldii.
They may be transmitted to the human body directly or indirectly through food and water, especially where hygiene practices are poor.
Here is a story by AJ at Centre For Disease Control And Prevention (CDC) On how he got infected with Salmonella by eating chicken.
Food poisoning by Salmonella is characterized by vomiting, diarrhea and fever however is caused by only a few species of Salmonellae such as Salmonella typhimurium and Salmonella heldelburg.
These species produce endotoxins that are associated with specific somatic antigens and as such cause food infections.
The poisoning is only known to occur when large numbers of viable Salmonellae are consumed with food.
The toxins…

Natural Sources Of Food Contamination

Microorganisms are ubiquitous in nature and this exposes them to enter food and diary products unless special efforts are used to prevent them.

However, the chemical composition and the physical conditions of the food determine the type of microorganisms that will develop on it. The natural sources of microbial contaminants in food include: soil, water, animal and plants and also during handling and processing of the food.

Let's elucidate on the natural sources of microbial contaminants in food:

(i) Soil
The soil contains the greatest variety of microorganisms than any other habitat. The soil is usually the first habitat for the isolation of microorganisms. Numerous number and kinds of microorganisms are present in fertile soils and contaminate surfaces of plants that grow on it as well as animals roaming and grazing over the land.
The soil is an important source of heat resistant spore-forming bacteria. Air current or running water onto foods carries soil particles.
However, initial was…

Technology In Yoghurt, Cheese And Acidophilus Milk Production

Milk contains microorganisms at the time it is drawn from the udder of the cow and it may be further contaminated during subsequent handling and processing. 
Milk is also an excellent medium for the growth of many bacteria due to it's exceptional nutritive value as it's main constituents include proteins, carbohydrates, fats, minerals, vitamins and water.
From these facts, the assessment of the significance of microorganisms in milk is important for the following reasons:

(i) The information on the microbial quality can be used to assess the sanitary quality and the condition of production of milk.
(ii) Identify and minimize the possibility of pathogens gaining entry into the milk.
(iii) Permitting bacteria to multiply in milk can lead to the production of chemical changes such as degradation of the milk constituents, making the product unwholesome.
(iv) Desirable chemical changes can be obtained from certain microorganisms in milk for the manufacture of diary products e.g Cheese, b…

Food Standards Agency UK (About And Roles Of FSA)

About FSAFood Standards Agency UK is a non ministerial department of the Government of United Kingdom, with headquarters in Petty France, London, UK, established on the 1st of April in the year 2000.
FSA ensures food safety and food quality standards in England, Wales and the Northern Ireland.
It enforces food regulations and legislations, nutrition policy and labeling policy in Northern Ireland and Wales respectively.
Website: FSA Official Website
It also ensures public health and consumer protection in England, and makes sure that foods manufactured and produced do not pose any health risk or hazard to the consumers.

Similar AgenciesFood Safety Authority Of IrelandNational Agency For Food And Drug Administration And ControlBangladesh Food Safety AuthorityNew South Wales Food AuthorityFood Standards ScotlandFood Safety And Standards Authority Of IndiaEuropean Food Safety AuthorityUS Department Of AgricultureCentre For Food SafetyFood Standards Australia New ZealandFood And Drug Administra…

Canadian Food Inspection Agency (About And Roles Of CFIA)

The Canadian Food Inspection Agency (CFIA) is a Canadian Government Agency that is charged with the duties to safeguard food, animals and plants which promotes health and economic growth in Canada.
CFIA inspects foods produced in Canada by manufacturers, agricultural products to make sure it conforms to food quality and food safety standards and to make sure it does not pose any health risk or threat to the entire Canadian citizenry.
CFIA ensures food safety, food quality, animal health, plant health, and international market access (i.e CFIA inspects foreign foods and agricultural products imported to Canada by the foreign market).

ABOUT CFIACFIA Official WebsiteEstablished: April, 1997Headquarters: Ottawa, Canada

Similar AgenciesFood Safety Authority Of IrelandUS Food And Drug AdministrationNational Agency For Food And Drug Administration And ControlBangladesh Food Safety AuthorityNew South Wales Food AuthorityFood Standards ScotlandFood Safety And Standards Authority Of IndiaEuropean F…

US Food And Drug Administration (About, Roles And Duties Of FDA)

Roles And Duties Of FDAFood and drug administration or US food and drug administration (FDA/USFDA) is a United States Government Agency under the Department of Health and Human Services, formerly known as Food, Drug And Insecticide Administration (FDIA).
FDA is charged with the duties of specifying standards for the manufacturing of foods and drugs, inspection of foods and drugs and ensuring that foods and drugs conforms to the standards for safety and quality .
FDA ensures the safety and quality of foods, drugs, medical devices, veterinary products, agricultural products, pesticides, insecticides and herbicides, cosmetics, vaccines, supplements.
USFDA also ensures consumer protection and public health.
They are also charged with the duties of sanctioning misbranded foods and drugs.
This agency sets legal standards for the food, agricultural, medical and pharmaceutical industries.
They make sure that foods and drugs manufactured are safe for consumers and do not pose any health risk or haza…

Food Safety Management System And HACCP (FSMS)

Food Safety Management
Food safety management is a systematic approach and practice of ensuring that foods conforms to the legal standards of food quality.
The purpose of food safety management system is to make sure that manufactured foods conforms to the legal standards of food quality and pose minimal health hazards.
There are laws and regulations governing the manufacturing of food, failure of food manufacturers to ensure that foods they produce attain the levels of conformity specified regarding the critical or mandatory attributes of food quality attracts several legal sanctions outlined outlined in food legislations and regulations.
These sanctions may result in great economic loss and at worst may result to the liquidation of the manufacturing company.
The attributes of food quality are those that deal with food safety and standards of identity of food and weights and measures.
Foods are regarded as safe when they present a minimum risk of illness when consumed.
An unsafe food is on…

Autolysis (Definition And Histology Of Autolysis)

Definition Of Autolysis
Autolysis can be defined as the destruction or digestion of a cell or the components of a cell by the action of its enzymes.
Autolysis in food is the process by which foods digests or are broken down by the action of enzymes.
Autolysis is also known as self-destruction or self-digestion.

Autolysis In Living Cells A cell is the smallest unit of plants and animals that can exist but cannot function on its own.
There are two types of cell which are plant and animal cells.

Components Of A CellNucleusChromosomeRibosomeLysosomeMitochondriaVacuoleNucleolus ChloroplastGolgi bodyEndoplasmic ReticulumCell WallCell MembraneCentriolesStarch Granules

An enzyme is an organic catalyst, usually proteinous in nature, which promotes chemical changes and accelerate metabolic reactions in living cells without changing its composition or being used up in the process.
Intracellular enzymes are responsible for autolysis in living cells.
In autolysis, the en…

Bacillus Cereus (Signs, Symptoms, Incubation Period And Prevention)

Bacillus Cereus

Bacillus cereus is an aerobic rod shaped lactose fermenting proteolytic, spore forming organism that produces an exotoxin which causes intoxication.

Some characteristics of bacillus cereus are abdominal pain, flatulence, diarrhea, headache, dizziness, dehydration, prostration, and sometimes nausea, vomiting, fever and chills.
The illness appears within 8-24 hours after the consumption of infected food.
The symptoms may last for less than 24 hours.
The organism produces an enterotoxin as well as lecithinase.
Intoxication occurs in foods in which Bacillus cereus can grow rapidly to high numbers.
Such food usually had been heated to destroy the competing microflora before holding for a prolonged period under room temperature conditions, which encourage food poisoning agents and toxin production.
Bacillus cereus intoxication can be controlled by preventing the multiplication of the organism in rice and other foods by preparing the food shortly before it is to be eaten.
In the case…

Clostridium Botulinum (Signs, Symptoms, Incubation Period And Prevention Of Botulism)

BotulismBotulism is a disorder caused by deadly botulinal toxins produced by clostridium botulinum.

Clostridium Botulinum

Clostridium Botulinum is a common microbial toxin which causes botulism, a disorder caused by deadly botulinal toxins produced by types of Clostridium botulinum, a gram negative, anaerobic, rod shaped, and spore-forming bacterium.
The spores are heat stable and may survive in poorly heated foods.
Also Read: Food Poisoning
Botulism results from consumption of food on which the microorganism had grown and produced toxin.
Clostridium Botulinum produces eight immunologically distinct heat-liable toxins designated A, B, C, D, E, F and G of which types A, B, E, and F are associated with human illness.
Type C and D are commonly associated with poultry and cattle.
Read Also: List Of Food Borne Diseases
Clostridium botulinum toxins appear to be simple proteins with neurotoxic activity.
The neurotoxic activity of botulinum toxin is associated with the toxins ability to interfere with …

Food Poisoning (Definition, Signs, Symptoms, Prevention And Types)

Food poisoning or food borne illness/disease is the process by which foods and food products are contaminated by microorganisms such as bacteria, viruses, parasites, fungi, protozoa, which when consumed are harmful to the human body.
Extrinsic biotoxins are the metabolic products of microorganisms which are toxic to animals.
Those that are produced by bacteria are called "bacterial toxins" while those produced by moulds are called mycotoxins.
These toxic metabolites and other agents of food borne diseases have contributed to increase human morbidity and mortality.
In the context of biological extrinsic poisons, it is important to understand the relationship and differences of the biological diseases that are associated with foods.

Types Of Food PoisoningBacterial food poisoningFungal food poisoningFood InfestationFood infectionViral food poisoningprotozoan food poisoningMetazoan food poisoningMicrobial food poisoning
Signs and Symptoms of Food PoisoningHeadacheDiarrheaFlatulenceDi…