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Basic Quality Criteria in Food Control • Food Quality Quality can be defined as combinations of attributes or characteristics of a product that have significance in determining the degree of acceptability of that product to the consumer. Food Quality It can also be said as measure of purity, strength, physicochemical & oregano-leptic characteristic of food products but the classical definition of quality is composite of these characters that differentiate between individual units of the products & have significance in determining the degree of acceptability of that unit by the user Definition: • Quality is a measure of the degree of excellence or degree of acceptability by the consumer. It can be defined as “summary of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs”. In simple words the product should have attributes to “satisfy the wants/ needs of the consumer or conformance with the user’s requirements”. It also covers the safety and value for money. Food quality can be considered as a complex characteristic of food that determines its value or acceptability to consumers. Thus it may be defined as “the composite of those characteristics which have significance in determining the degree of acceptability by the buyer. These characteristics should also have the ability to differentiate individual unit of the product.” Every food product has characteristics and indices measurable by sensory, physicalchemical, or microbiological methods. Some characteristics are easily perceived; others are unseen. Understanding these quality characteristics and being familiar with the appropriate measuring tools are vital to quality control and the quality assurance of food products. Components: • The important components of food quality are: food safety, sensory characteristics and nutritional value. Safety of food is a basic requirement of food quality. “Food safety” implies absence or acceptable and safe levels of contaminants,adulterants, naturally occurring toxins or any other substance that may make food injurious to health on an acute or chronic basis. Besides safety, quality attributes include: nutritional value; organoleptic properties such as appearance, colour, texture, taste; and functional properties. Components: The quality attributes are outlined in Table and includes primarily sensory attributes and hidden attributes. The sensory attributes include characteristics such as colour and appearance, viscosity and consistency, smell, taste, touch etc. The hidden characteristics are those which cannot be evaluated with human senses and yet are of real importance to human health and welfare. Nutritive value is one of the hidden characteristics, which is now considered by the consumers as a quality attribute. Adulterants and toxicants are the other hidden characteristics. Toxic substances may be of microbial origin, veterinary drugs residues, pesticide residues or heavy metals. Table1. The quality attributes The quality attributes are outlined in Table and includes primarily sensory attributes and hidden attributes i) Food safety: In order to understand “food safety” we must first know the terms safe and hazard. “Safe” means that nothing harmful happens when we consume a food. A “hazard” is the capacity of a thing to cause harm. The objective of the food safety is to protect the food supply from microbial, chemical and physical hazards or contamination that may occur during all stages of production and handling-management of animals at farm, transportation,storage of raw milk, processing, production of value added products, distribution and storage of end products. It aims for keeping food wholesome and free from food borne illness. The important associated definitions and factors are described for better understanding of the food safety. a) Food borne illness: Food borne illness or food poisoning is caused by consuming food contaminated with pathogenic bacteria, toxins, viruses or parasites. The contamination may or may not alter a food’s organoleptic properties but cause illness and disease to human beings after consumption and usually arises from improper handling, preparation or storage of food. Food-borne diseases are classified as food infections or food intoxications. Food infections involve microorganisms present in the food at the time of consumption which then grow in the host and cause illness and disease.Food intoxications involve toxic substances produced in foods by microorganisms prior to consumption and cause disease upon ingestion.The toxin producing microorganisms need not to grow in the host to produce a disease or even be present in the food. So we must acknowledge that intoxication can occur even if no viable microorganisms are ingested. (b) Food hazards: Food becomes hazardous by contamination. Contamination is the unintended presence of harmful substances or microorganisms in food. Food hazards can be defined as a biological, chemical or physical agent in a food, with the potential to cause an adverse health effect (Table). Physical hazards are foreign particles, like glass/wood or metal pieces, stone, bone fragments, feathers, fibre, hair, etc. Chemical hazards include substances such as cleaning solutions and sanitizers, non permitted adulterants, pesticide and heavy metal residues. Biological hazards come mainly from microorganisms Quality ,Ministry of Health is pursuing a broad and long-term sciencebased strategy to improve the food safety and to better protect the public health. Part of this strategy is a farm-to-table approach to improve the safety of food at each step in the food production, distribution, and marketing chain Table2. Types of Food Hazards (c) Food Safety Management Systems Certification(FSMS): (d) The Food Safety and Standards Act, 2006: The chapter six of the Act titled as “Special Responsibilities as to Food Safety” deals with responsibilities of the food business operator, liability of manufacturers, packers, wholesalers, distributors and sellers and recall procedures (e) Safety concerns: We know that the goal of food safety is to reduce the size of risks to the lowest reasonable level without severe disruption of the food supply. For this we should first identify hazards related to foods or food components and then estimate the size of the risk that the hazard will cause. It is important to note that all foods have some degree of risk and that no food is absolutely “safe.” The important consideration becomes “the size of the risk and how the size of the risk can be reduced” without eliminating the food source. Specific food safety concerns differ markedly and include • • • • • • • • • • • Additives, colours and flavours. Antibiotics and other food additives. Fertilizers and other growing aids. Irradiation. Microbiological contamination. Naturally occurring food toxicants. Nutrition. Pesticides. Pollutants. Processing, packaging and labelling. Tampering. (f) Adhering to Safety Standards: The advantages associated with adhering to food safety standards are: • Ensures safety of food products. • Greater health protection. • Increased international acceptance of food products. • Helps to meet applicable food safety related statuary & regulatory requirements. • Demonstrate conformance to international standards and applicable regulatory requirements. • Reduces risk of product/service liability claims. (g) Recent Concerns of Food Safety: Prions, genetically modified foods, the incidence of bovine spongiform encephalopathy (BSE), and dioxincontaminated foods are some of the new food safety concerns. Prions are one of the new sources of food borne diseases. A prion is the short form of proteinaceous infectious particle. Dr. Stanely Prusiner coined the word “prion” as a name for the infectious agent, by combining the first two syllables of the words “proteinaceous” and “infectious.” While the infectious agent was named a prion, the specific protein that the prion was made of was named PrP, an abbreviation for “protease-resistant protein”.The normal form of the protein is called PrPC, while the infectious form is called PrPSc, which stands for prion protein of scrapie. Prions are generally quite resistant to denaturation by protease, heat, radiation, and formalin treatments, although potency or infectivity can be reduced. Prions enter cells and apparently believed to infect and propagate by refolding abnormally into a structure which is able to convert normal The diseases associated by prisons are: Creutzfeldt-Jakob Disease (CJD), Bovine spongiform encephalopathy (BSE- commonly known as “mad cow disease”), fatal familial insomnia and kuru (translated as “to tremble with fear”). Dioxin–Contaminated Foods: Dioxin is the popular name for the family of halogenated organic compounds, the most common consisting of polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzopdioxins (PCDDs). PCDD/PCDFs are industrial pollutants that persist in the environment. They have been shown to bio accumulate in humans and wildlife due to their lipophilic (fat loving) properties. Dioxins are a carcinogen in higher amounts, and cause developmental and reproductive problems. They are absorbed primarily through dietary intake of fat, as this is where they accumulate in animals, including humans Genetically Modified (GM) Foods: The GM foods are produced from genetically modified organisms (GMO). A GMO means: an organism that has been modified (manipulation of DNA) by gene technology. Genetically modified (GM) crops and food are being grown and consumed by the public. The advantages associated are: increased yields from agriculture,more powerful control of pests and weeds, reduced use of some agrochemicals and enhancement of nutritional value or other characteristics of crops, etc. There are many things which people hold up as possible dangers of genetic modification: risk of transferring crop traits to wild species, negative impacts on wildlife from more powerful control of pests and weeds, increased use of some agrochemicals, increased corporate control of seed supply and; limited studies on food safety concerns on human health in form of toxins/ allergenic reactions/ reduction in good micro flora of duct, etc. ii) Nutritional Value: Nutritional value of the product has grown in importance as consumers have become better informed about foods. The consumers demand for nutritional labelling in addition to food safety. Nutritional changes occur in foods during handling, processing and storage due to microbiological, enzymatic and chemical reactions. One of the principal responsibilities of the dairy technologists is to preserve nutrients through all phases of food acquisition,processing, preparation and storage. ii) Nutritional Value: As a food processor, we should have good knowledge of the stability of nutrients under different conditions. Vitamin A is highly sensitive (i.e., unstable) to acid, air, light, and heat; on the other hand,vitamin C is stable in acid but is sensitive to alkalinity, air, light, and heat. Because of the instability of nutrients under various conditions and their water solubility, cooking losses of some essential nutrients may be greater than 75%. In modern food processing operations, however, losses seldom exceed 25%. The food should not contain any toxic/ anti- nutritional substances. iii) Sensory Characteristics: The sensory characteristics of foods and materials are based on perception of human senses i.e. senses of sight, smell, taste, touch and hearing. QUALITY EVALUATION • Three methods; 1 Subjective method 2. Objective method 3.microscopic method • 1. Subjective Method; Evaluating quality are based on opinion of the investigators. it includes sense organs. It is usually a physiological reaction which is a result of past training, experience of the individual influence of personal preference & power of perception. It is also referred as subjective or sensory method e.g. flavor, color, touch, odour and taste. • 2. Objective method; objective methods of quality are based on observations from which the human perception is excluded. They are based on scientific tests. • Physical methods of Measurement; This is perhaps the quickest method s are generally. They are concerned with such attributes of product quality as size, texture, color, consistency imperfections or they may be concerned with process variables like headspace, fill, drained weight, or vacuum • • Chemical methods of measurement. Standard analysis methods are generally used for quantitative chemical evaluation in most cases , but these chemical analysis are often too long & tedious as a result industries have developed method termed as quick test for such as those for ; enzymes, moisture, fiber, pH or acidity • 3. Microscopic method • They have excellent application in a quality control programme because they help in determination of microbial count, spoilage protection in fresh and processed products and can differentiate between cell types and organisms. These methods can be divided into two categories • Adulteration & contamination Examination will indicate the presence of molds, insects, excreta or foreign material. Each test is specific. Differentiation between cell type , tissue type,& m/o of various stored foods