Introduction to food analysis

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Introduction to food analysis
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Food analysis objectives

• Developing a theoretical and practical
  understanding of the methods used to analyse
  foods
• chemical analysis
• physical analysis
• to ensure high and consistent quality of foods in
  the food industry

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Proximate analysis of foods

• Definition
• estimation of the main components of a food
  using procedures that allow a reasonably rapid
  and acceptable measurement of various food
  fractions without the need for sophisticated
  equipment or chemicals

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Proximate analysis

• Therefore crude estimation crude fat, crude
  protein
• not true value but adequate

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Proximate analysis of foods

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Further development in food analysis due
adulteration

• Prior to the 18th century food adulteration not a
  serious problem
• Food adulteration and deception???? rampant in
  18th century
• high value foods substituted for cheap often
  hazardous materials

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Food adulteration

• adding stone grinds (40) to flour
• milk samples contained lead chromate (red lead)
• Black pepper gravel??? , leaves, twigs ?????
• Vinegar lemon juice sulphuric acid
• Coffee roasted cereals, pulses or vegetables,
• Tea spent, re-dried tea leaves
• Sugar sand, dust,

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• Milk water, starch, gums and soda
• Beer poison berry extract gave flavour, colour
  and intoxicating effect
• Butter excessive salt water, potato flour
• Chocolate starch and ferric oxide

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• Quality
• the sum of features, characteristics and
  properties of a product which bear on its ability
  to satisfy stated or implied needs

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• Quality control (QC)
• operational techniques and activities which
  sustain quality of goods and services
• QC staff 100 inspect carcasses at abattoir
• in cannery, check seems, fill weights, pH etc
• laboratory staff carry out analytical tests
• dairy plant fat test freezing point
• phosphate test
• direct microscopic counts
• lab staff may conduct sensory analysis

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Quality values of foods analysis

• Legal
• hygiene, additives, residues, contaminants and
  composition
• Nutritive
• national nutritional guide lines, undesirable
  (additives residues)
• Health
• over laps with legal and nutritive values
• Food Standards
• alert of health hazards during pregnancy
• qualifying the value of food categories

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• Technological
• convenience foods heat and eat
• less processing / perceived fresh
• Sensory
• like or dislike measurement of quality via
  senses
• Socio-ecological
• food packaging verses pollution
• conversion of rain forest to cow pastures
• effluent into water ways

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Quality that may be evaluate?

• Attribute which measure qualitative character
  of food products
• Variables which measure quantative characters of
  food products

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Food chemsitry

• Food chemistry is the study of chemical processes
  and interactions of all biological and
  non-biological components of foods. The
  biological substances include such items as meat,
  poultry, lettuce, beer, and milk as examples. It
  is similar to biochemistry in its main components
  such as carbohydrates, lipids, and protein, but
  it also includes areas such as water, vitamins,
  minerals, enzymes, food additives, flavors, and
  colors.

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• discipline also encompasses how products change
  under certain food processing techniques and ways
  either to enhance or to prevent them from
  happening

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• And so to study the chemical processes and
  interactions of all biological and non-biological
  components of foods we need to food analysis

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Food components

• Water
• Carbohydrates
• Lipids
• Proteins
• Vitamins
• Minerals
• Enzymes
• additives

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• During this course exploring the different types
  of reactions and changes that may occur during
  food processing and to control it by food analysis