Food Spoilage and Food Borne Diseases

Food Quality and Control

BioTech311126506

Contents: FOOD SPOILAGE:Fitness of a food Causes of food spoilage

FOOD BORNE DISEASES:Food infectionFood intoxication

FOOD QUALITY AND CONTROL:Deterioration of food qualityQuality factors for consumer safety

Fitness of a food:

Definition: A food is said to be fit, if a consumer with knowledge of the details of its production eats it on seeing the material itself.

Conversely the food is considered to be spoiled and is unfit for consumption when consumers refuse it as food.

Food Spoilage

Microorganisms

Enzymes

Insects , rodents etc.

Chemical reactions

Environmental factors

Time

Action of Micro organisms on food:

• The micro organisms mainly include the Bacteria, Yeast and Molds.

• In case of bacteria we can take an example of Streptococcus lactis and coliform bacteria which show a Metabiotic effect.

• Raw milk which supports the acid fermentation by the growth of these two micro organisms and the acid formed inhibits their growth.

• Afterwards a film of yeast and molds grow over the top and thus reduce the acidity facilitating the growth of Proteolyticbacteria.

• The common food spoilage molds include the following:Molds Food

Mucor racemosus, Rhizopus bread, berries, fruits, stolonifer vegetables

Sclerotinina rots of vegetables, fruits

Sporotrichum white spots in chilled meat

Botrytis cinerea diseases in grapes

Helminthosporium sp. Plant pathogens

• Enzymes play a crucial role in the food quality and on the other side of the coin, they are also the components in destroying the food.

• The enzymatic changes are in food are desirable to some extent and beyond that they prove to be fatal to the food’s quality (rotting).

• Examples: Pepsin in a living animal helps in digesting a

protein but does not affect the intestine. On the other hand it causes the proteolysis of the organs containing it.

Similarly uncontrolled ripening results in the spoilage of fruits and vegetables.

Insects, Parasites & Rodents:

Insects

Parasites

Rodents

• Microbial attacks on food

• Contamination of food items.

• Enters the body through poultry

• Improper cooking

• Contaminates by consuming food

• Contaminates also by droppings, filth etc.

• Chemical reactions also deteriorate the food.

• The unsaturated fatty acids present in foods undergo the process of oxidation when exposed to open air and thereby giving rise to oxidative rancidity in fat rich foods.

• Hydrolytic reactions also cause undesirable changes in the food.

• There is a chance of loss of vitamins due to oxidation.

Environmental Factors:Temperature

Moisture

HumidityAir

Light

• The deterioration of the quality of food progresses along with time.

• The quality of the food remains at its peak for some time, soon after its cooking or slaughter and after that the deterioration takes place thus spoiling the texture and taste.

The following are the various foods that are spoiled when subjected to all the factors that are mentioned:

• Vegetables & Fruits• Cereal and its products• Bakery products• Dairy products• Meat, Poultry & Sea foods• Spices• Sugar & Confectionery items• Alcoholic beverages

Food InfectionFood Intoxication

Food Infection:The food serves as a culture medium for the growth of pathogens to increase their number and thus cause infections.The contaminated food does not support the growth of the pathogenic organisms but acts as a carrier for them.

Food Intoxication:

The contaminated food contains poisons or toxicants which lead to food poisoning and when ingestion of such foods into the body results in food borne illness.

The various food borne diseases due to food infections:

• Salmonellosis• Bacillus cereus Gastroenteritis• Escherichia coli Infection• Shigellosis• Yersiniosis• Vibrio• Beta Hemolytic streptococcal infectionInfections due to food borne parasites:

• Amebiasis• Trichinosis

The various food borne illness due to food intoxication:

There are mainly four types of food intoxications. They are:

• Bacterial food intoxication• Fungal intoxications (Mycotoxins)• Biological toxins• Chemical Poisoning

Fungi Bacteria

Quality of food and food products may be defined as the degree of excellence of the various characteristics that influence consumer acceptance as well as his safety.

Consumer safety requires the evaluation of food quality with respect to nutritional quality, hygienic conditions and keeping i.e. storage capacity.

Food Quality

Food quality controlThe consumer cannot judge the nutritional qualities of a food and the presence or absence of pathogens, contaminants, toxins and chemical additives.

Hence there is a need for quality control of various foods to meet the demands and satisfaction of consumers. Sensory evaluation of foods is to be carried out so that the quality of different foods are maintained well.

Appearance factors

Textual factors

Flavor factors

Quality factors

The Problem• Resistance and virulence of emerging pathogens• Patchwork system of food safety regulation• Lack of an effective, low cost method of ensuring safety of food products• Lack of regulatory oversight beyond commercial facilities• Lack of effective consumer education programs

Regulatory Issues:

•Food Additive Regulation•Labeling•Novel Food Processing•Standardization

•Responsibility (liability)•Food Irradiation•Genetic Modifications•Consumer protection

The History of HACCP

HACCP initiated in early 1960s as cooperative effort.

PillsburyNASANatik labs of U.S. ArmyU.S. Air Force Space Laboratory

Purpose was to produce zero defect food for astronauts.

HACCP

Seven Steps of HACCP:

Assess Potential HazardsDetermine Critical Control PointsEstablish requirements for each CCPEstablish procedure to monitor each CCPEstablish corrective action if deviationEstablish record keeping proceduresEstablish procedure to monitor effectiveness.

Good Manufacturing Practices (GMP)

Procedures developed to ensure production of safe, wholesome foods and to provide safe working environment.Not "process specific", relate to entire operation.GMPs include facilities/grounds, equipment pest control, receiving and storage, process control, product recall and personnel training.

GMPs and HACCP

GMPs establish guidelines, requirements, and expectation for reducing adulterationGMPs along cannot guarantee safetyHACCP represents joint effortPolicies, procedures, regulations are evolving.

ISO - 9000

International Food Quality StandardsNon-prescriptive

Non-prescriptive standard that does not specify how a company's quality assurance must occur, but mandates that a company define appropriate quality standards, document its processes, and prove that it consistently adheres to both.