Transcript Basic Quality Indices in Food Control

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
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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
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• 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