Food Hygiene Unit 1 Food Inspection Topic Inspection

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Food Hygiene Unit 1: Food Inspection Topic: Inspection of food items Practical 7

Food Hygiene Unit 1: Food Inspection Topic: Inspection of food items Practical 7

Food Inspection An effective food safety system is important. Inspections are required of –

Food Inspection An effective food safety system is important. Inspections are required of – Systems – Processes – Facilities – Products

Importance of food Inspection Protect the health of populations – Ensure compliance with standards

Importance of food Inspection Protect the health of populations – Ensure compliance with standards – Prevention/control of FBI Ensure social stability Promote and maintain trade relations

Food Inspection The critical examination of food using various methods/techniques: – Observation- blemish, dents,

Food Inspection The critical examination of food using various methods/techniques: – Observation- blemish, dents, leaks – Palpation – spoilage of fish – Incision- cutting into meats – Auscultation – shaking and listening – Percussion - tapping cans – Organoleptic – smell, taste

Labelling Criteria Name of product Brand name Weight/volume of product Manufacturer/Distributor Ingredients Dates

Labelling Criteria Name of product Brand name Weight/volume of product Manufacturer/Distributor Ingredients Dates

Product Dating “Sell by” date – tells the store how long to display the

Product Dating “Sell by” date – tells the store how long to display the product for sale. Product should be purchased ahead of this date to allow time for consumption “Best if used by” date – recommended for best flavour or quality; not a purchase or safety date. “Use by” date – last recommended date for use of the product while at peak quality; this is determined by the manufacturer of the product. “Expiry” date – Recommended by the manufacturer, safety of the product cannot be guaranteed beyond the indicated date.

Fish What factors are responsible for fish spoilage? Under what conditions do you purchase

Fish What factors are responsible for fish spoilage? Under what conditions do you purchase fresh fish?

Fish Freshly caught fish relatively wholesome Deterioration of quality commence upon leaving water Principal

Fish Freshly caught fish relatively wholesome Deterioration of quality commence upon leaving water Principal of condemnation is decay Fish Spoilage Microbiological Reasons Chemical Reasons Physiological Reasons

Microbiological Reasons for fish Spoilage Several spp. of microbes are always present in surface

Microbiological Reasons for fish Spoilage Several spp. of microbes are always present in surface slime and intestinal tract Bacteriostasis in live fish Flesh of life healthy fish sterile Upon death microbes multiply rapidly and attack tissues Since microbes survive at low temperatures in the ocean, can resist refrigeration temperatures Need to store below 4. 4 C upon being caught

Physiological reasons for fish spoilage Glycogen depletion in muscles Little glycogen available to be

Physiological reasons for fish spoilage Glycogen depletion in muscles Little glycogen available to be converted to lactic acid Limited lactic acid to retard microbial growth

Chemical Reasons for fish spoilage Enzymatic action on certain constituent of fish – Autolysis

Chemical Reasons for fish spoilage Enzymatic action on certain constituent of fish – Autolysis or self digestion Undesirable chemical substances produced by the growth and activities of bacteria One such substance is tri-methyl amines – Responsible for the fishy odour in spoilt fish Oxidation - rancidity

Fish Inspection 1. Oganoleptic – Appearance – Odour 2. Palpate – consistency – A

Fish Inspection 1. Oganoleptic – Appearance – Odour 2. Palpate – consistency – A sand paper feel denotes staleness – Lack of moisture at the surface – Lack of firmness of flesh and elasticity – Odour should not be fishy

Fish Accept 4. 4 C or lower Bright red closed gills Bright clear, bulging

Fish Accept 4. 4 C or lower Bright red closed gills Bright clear, bulging eyes Firm flesh Firmly attached scales with moderate amount of slime Mild ocean/seaweed smell Blood along the b-bone in visceral cavity bright red Body stiff and tail rigid Surrounded in crushed self draining ice Carcass sinks in water Reject >4. 4 C Pale pink, dull gray gills, slimy Dull, sunken, cloudy, red rimmed eyes Dull flesh with missing scales Soft flesh, leaves imprints Lifts from backbone easily Bone alone the b-bone cavity dark to black with foul odour Limp pliable body Strong fishy or ammonia smell Yellow slime Carcass floats in water

Keeping quality The less fish is handled the longer it will remain wholesome Keep

Keeping quality The less fish is handled the longer it will remain wholesome Keep fish embedded in finely shaven ice Fish fillet, sliced fish or fish with exposed surface should not come in direct contact with ice or water – Will result in more rapid spoilage, change in flavour and appearance

EGGS Eggs usually mean those of hens but may include those of ducks and

EGGS Eggs usually mean those of hens but may include those of ducks and turkeys also. Made up of three main parts: – Shell – White (albumen) – Yolk

Parts of an Egg

Parts of an Egg

Parts of the egg Shell Composed mainly of calcium carbonate May be brown or

Parts of the egg Shell Composed mainly of calcium carbonate May be brown or white depending on the breed of chicken Quality, flavour, cooking characteristics and nutritional value not affected by colour Air Cell Pocket of air formed at large end of egg Caused by contraction of the contents during the cooling process Increase in size as the egg ages Shell membrane There are 2 - inner and outer shell membrane Surround the albumin Provide protective barrier against bacterial penetration Air cell forms between these 2 membranes

Parts of the egg Albumen (white) Major source of protein and riboflavin Chalazae Twisted,

Parts of the egg Albumen (white) Major source of protein and riboflavin Chalazae Twisted, cord-like strands of egg white Anchor yolk in centre of egg Prominent chalazae indicative of freshness Vitelline (Yolk) Membrane Closer seal which holds the yolk in place Germinal Disc Yolk Colour varies with feed Colour doesn’t indicate nutritive value Major source of vitamins, mineral and fat; and ~1/2 of the protein

Air Cell Empty space between the white and the shell at the large end

Air Cell Empty space between the white and the shell at the large end of the egg. As a freshly laid egg is cooled, the contents contract and the inner membrane separates from the outer membrane forming an air cell. As the egg ages, moisture and carbon dioxide leave through the pores and air enters to replace them causing the airspace to get larger. Air cell is visible at the flattened end of a peeled boiled egg.

Air Space in Egg – The shell has an air space of less than

Air Space in Egg – The shell has an air space of less than 1/4” deep – The air space gets larger with time

Blood Spots Also called meat spots Found on egg yolk and results from the

Blood Spots Also called meat spots Found on egg yolk and results from the rupture of blood vessels on the yolk during the formation of the egg or in the oviduct. Candling can reveal eggs with blood spots As the egg ages, the yolk takes up water from the albumen and dilutes the blood spots, hence blood spots indicate a fresh egg. Eggs with spots are fit for consumption.

Bloom Freshly laid eggs have a dull appearance The coating or covering on the

Bloom Freshly laid eggs have a dull appearance The coating or covering on the egg that seals the pores. Prevents bacteria from getting into the egg and reduces moisture loss Washing removes the bloom Protection can be restored from a light coat of mineral oil.

Conditions that render egg unsound MICROBIAL – Mold (penicillum, cladosporum) – Pseudomonas – causing

Conditions that render egg unsound MICROBIAL – Mold (penicillum, cladosporum) – Pseudomonas – causing black rot or green rot – Avian TB (rare) – Salmonella – from faeces of the bird

Conditions that render egg unsound PHYSICAL – Cracked eggs – will decompose quickly –

Conditions that render egg unsound PHYSICAL – Cracked eggs – will decompose quickly – Storage position – storage for a long time in inverted or horizontal position causing adherence of yolk to shell – Evaporation – resulting in enlarged airspace

Conditions that render egg unsound CHEMICAL – Mainly due to enzymic action – Enzymes

Conditions that render egg unsound CHEMICAL – Mainly due to enzymic action – Enzymes cause eggs to become watery. – Loss of CO 2 changes p. H and causes a transfer of water from the white to the yolk. – The yolk of a freshly laid egg will stand in a viscous white.

As an egg ages, several changes occur: Water moves from the white to the

As an egg ages, several changes occur: Water moves from the white to the yolk The yolk structure weakens The egg whites becomes thinner The air space increases Bacteria may enter through the shell A “bad egg” smell occurs due to the production of H 2 S and other compounds

Testing Egg for freshness Shaking Candling Immersion/Brine test Yolk Index Test

Testing Egg for freshness Shaking Candling Immersion/Brine test Yolk Index Test

Testing Egg for Freshness Shaking Fresh eggs make no sound Stale eggs make a

Testing Egg for Freshness Shaking Fresh eggs make no sound Stale eggs make a sloppy sound Candling – Hold egg before powerful light source – Egg quality judged by transparency – While rotating egg yolk, albumen and air space are visible – Albumen is translucent without spots Stale Egg Albumen becomes dark and opaque Yolk less visible Enlarged air space Blood spots due to the growth of microbes/ cracks can be detected

Testing Eggs for freshness Immersion/ Brine test Involves floating egg in water – 10%

Testing Eggs for freshness Immersion/ Brine test Involves floating egg in water – 10% solu. (2 oz salt to 1 pt water) – Fresh egg sinks – Stale egg float in varying positions Shrinkage of the albumen Carbon dioxide and moisture levels, Replaced by air through pores in egg shell Increased air space

Testing Egg for freshness Yolk Index Test – Dividing the height by the diameter

Testing Egg for freshness Yolk Index Test – Dividing the height by the diameter of yolk Stale Egg – weakening of the vitelline membrane – Absorption of water from albumen Cracking egg on a plate Fresh Egg Rounded yolk Stands up in the viscous white Yolk flattens Thin liquified albumen – Degeneration of the gelatinous structure Difficult to separate yolk from albumen Sour odour detected

Evidence of Unsoundness in Egg Degree of suitability of the yolk – – Adherence

Evidence of Unsoundness in Egg Degree of suitability of the yolk – – Adherence of yolk to shell Dark spots Disintegration Colour changes Depth of air space – >1/4” Presence of blood spots Presence of discoloured albumen Evidence of the embryo Presence of cracks in the shell Unpleasant odour

Inspection of Egg Accept 4. 4 C or lower No odour Clean Unbroken Firm

Inspection of Egg Accept 4. 4 C or lower No odour Clean Unbroken Firm yolk Reject >4. 4 C Sulphur smell/off odour Dirty Broken/cracked

Examination of Egg Colour change, Odour change, packaging, temperature, physical contamination Liquid Egg –

Examination of Egg Colour change, Odour change, packaging, temperature, physical contamination Liquid Egg – <4. 4 C – In tack packages – No signs of thawing Dehydrated Egg – No caking

Meat Accept 4. 4 C or below Beef - bright, cherry red; aged beef

Meat Accept 4. 4 C or below Beef - bright, cherry red; aged beef may be darker in colour; vacuum packed may appear purple in colour Lamb – light red Pork – light pink, firm white fat Texture – firm and spring back when touched No odour Package clean and in tact Reject Above 4. 4 C Beef – brown or green Lamb – brown, whitish surface covering the lean meat Pork – excessively dark colour, soft or rancid fat Texture – slimy, sticky or dry Sour/rancid odour Package – broken cartons. Dirty wrappers, torn packaging, vacuum packaging with broken seals

Poultry Accept Below 4. 4 C No discolouration Texture – firm and springs back

Poultry Accept Below 4. 4 C No discolouration Texture – firm and springs back when touched No odour Package – surrounded by crushed self draining ice Reject >4. 4 C Purple or green discolouration around neck; dark wing tips Stickiness under wings or around joints Abnormal/unpleasant odour

Smoked fish Accept Fresh clean, smoky smell Firm, dry free from blood stains Reject

Smoked fish Accept Fresh clean, smoky smell Firm, dry free from blood stains Reject Sweaty, soft, slimy flesh Mould growth Uncharacteristic smell

Salted Fish Accept Fresh, firm, clear, dry Stored in cool dry place Should be

Salted Fish Accept Fresh, firm, clear, dry Stored in cool dry place Should be protected from all sources of contamination Reject Soft, moist flesh Pink/green fungal growth Foul odour Improperly stored Maybe infested with Lasioderma or other pests

Pickled Fish Accept Fish covered with liquor Firm fish Free from blood stains and

Pickled Fish Accept Fish covered with liquor Firm fish Free from blood stains and broken pieces Reject Fish partially covered wit liquor Fish covered with muddy liquor Fish with a foul/rancid odour Blood stained flesh, discoloured Fish broken in pieces

Shellfish Mollusks – soft bodied, protected by hard shell – Oysters, mussels, clam Crustaceans

Shellfish Mollusks – soft bodied, protected by hard shell – Oysters, mussels, clam Crustaceans – body encased in hard, close fitting shell. – Possess legs, flesh firmer than mollusks – Lobster, crab, shrimp

Shellfish - Oyster Most widely consumed mollusks Require 4 -6 years to maturity Thrive

Shellfish - Oyster Most widely consumed mollusks Require 4 -6 years to maturity Thrive best in brackish water – Can breed in water highly polluted with sewage – Oyster reflect the bacteriological quality of water – Oyster can self cleanse in chlorinated water

Shell fish - oyster Accept Tightly closed unbroken shell Outside clean Pleasant odour Sink

Shell fish - oyster Accept Tightly closed unbroken shell Outside clean Pleasant odour Sink in water Liquor p. H 6 -7 If shucked - <4. 4 C Reject Opened shell- don’t close when tapped Unpleasant odour Excessive dirt and slime Sticky or dry Floats in water Liquor p. H more acidic If shucked - >4. 4 C

Lobster Accept Reject Muscular activities in No resistance in tail Discolouration under Odour free

Lobster Accept Reject Muscular activities in No resistance in tail Discolouration under Odour free tail Free of dirt and Slimy exudate under slime claws If scalded alive- shell Dark colour of the will have pink colour shell when scalded Foul odour

Crab Accept Should be accepted alive Very active No offensive odour Reject Offensive odour

Crab Accept Should be accepted alive Very active No offensive odour Reject Offensive odour Sluggish dead

Frozen processed foods Accept Solid frozen -14 to -21 C Ice soft and flaky

Frozen processed foods Accept Solid frozen -14 to -21 C Ice soft and flaky In tack packaging Clean packages Reject Evidence of thawing – Fluids or frozen liquid in case bottom – Ice crystals – Water stains Damaged packages Unfrozen foods > 14 C- icecream

Reduced Oxygen Packaged Food Accept 4. 4 C or lower unless otherwise specified by

Reduced Oxygen Packaged Food Accept 4. 4 C or lower unless otherwise specified by the manufacturer If frozen – frozen Packages in tact Use by date evident Acceptable colour Reject >4. 4 C, unless otherwise specified If frozen- not frozen Torn or leaking packages Pass use by date Unacceptable colour, slime, bubbles, and excessive liquid

Dairy Milk, butter, cheese Reject Accept >4. 4 C Dirty, broken packages <4. 4

Dairy Milk, butter, cheese Reject Accept >4. 4 C Dirty, broken packages <4. 4 C Clean, unbroken Milk: sour, bitter or moldy packages taste, ropiness, Fresh characteristic discolouration, off- odour smell Butter: sour, bitter; mold Milk: sweetish flavour growth; uneven colour, Butter: sweet flavour, rancid smell uniform colour, firm Cheese: unnatural mold, texture uneven colour, abnornmal Cheese: typical flavour, flavour and texture and uniform colour

Cheese Asiago Cheese Blue Cheese

Cheese Asiago Cheese Blue Cheese

UHT Foods Accept In tack package In tack seal <4. 4 C when opened

UHT Foods Accept In tack package In tack seal <4. 4 C when opened Proper labels Use by date Reject Leaking, punctured Leaking packages Dirty packages >4. 4 C after opened No label No use by date

Fresh Fruits & Vegetable General rejection criteria – Insect infestation – Evidence of mold

Fresh Fruits & Vegetable General rejection criteria – Insect infestation – Evidence of mold – Damaged surfaces – Wilting and Mushiness – Discolouration & dull appearance – Unpleasant odours – Unpleasant taste

Ackee Freshly picked mature ackee Introduced 1778 – West Africa Noted- 1875 1 st

Ackee Freshly picked mature ackee Introduced 1778 – West Africa Noted- 1875 1 st documented- 1904 Hypoglycin cpd. Responsible for ackee poisoning “Jamaica Vomiting Sickness Syndrome”

Ackee Two toxic substances can be extracted from the fruit – Hypoglycin A &

Ackee Two toxic substances can be extracted from the fruit – Hypoglycin A & Hypoglycin B Hypoglycin A, can be found in the aril of the fruit Unripe fruit has a higher concentration of hypoglycin (x 20) Seed and membrane at the base of the seed are always poisonous Source: http: //www. scq. ubc. ca/the-ackee-fruit-blighia-sapida-and-its-associated-toxic-effects/

Ackee Hypoglycin A is an unusual amino acid Has the ability to significantly reduce

Ackee Hypoglycin A is an unusual amino acid Has the ability to significantly reduce blood glucose levels and induce hypoglycemia Depletion of glucose reserves and the inability of cells to regenerate glucose leads to hypoglycemia. Source: http: //www. scq. ubc. ca/the-ackee-fruit-blighia-sapida-and-its-associated-toxic-effects/

Ackee Potential risk behaviours for ackee poisoning include the following: – Consumption of unripe

Ackee Potential risk behaviours for ackee poisoning include the following: – Consumption of unripe ackee fruit – Consumption of ackee that has been forcibly opened – Reuse of the water in which an unripe ackee has been cooked

Stages in maturity of ackee Bearing seasons – January to March – June to

Stages in maturity of ackee Bearing seasons – January to March – June to August Fruits bear in clusters, turn red on reaching maturity Split open along the seams with continued exposure to the sun

Ackee maturity guide 1) SMALL UNOPENED – small, hard, immature, and unopened. Unsuitable for

Ackee maturity guide 1) SMALL UNOPENED – small, hard, immature, and unopened. Unsuitable for processing or eating. 2) SLIGHTLY OPENED – Slightly open, pod lobes split, seed and aril visible – (Warning: At this stage, the hypoglycin (toxin) is at a dangerously high level. Fruit can be reaped for racking but not for processing or eating. 3) FULLY OPENED – Fully opened pod: seed and aril clearly visible. Suitable for processing and eating. 4) ADVANCED SHRIVELLING – Advanced Shrivelling of pod, onset of spoilage, aril begins to decay or rot.

Ackee maturity guide Fruit Maturity • Ackee takes 7 -8 weeks to attain full

Ackee maturity guide Fruit Maturity • Ackee takes 7 -8 weeks to attain full maturity • During weeks 2 -3 of fruit development, the fruit doubles in size, after which the fruit increases at a much slower rate • At full maturity the fruits are pear shaped and acquire a red or a yellow tinge with red colouration • The pods then open revealing the seeds and 3 fleshy arilli

Inspection of canned foods Canning is a widely used method of food preservation so

Inspection of canned foods Canning is a widely used method of food preservation so the inspection of canned foods is unavoidable. At least 10%of consignment should be inspected – If >2. 5% rejected – action

Canned Foods It is important to: – Identify the can contents – Identify the

Canned Foods It is important to: – Identify the can contents – Identify the brand – Identify the weight – Condition on the can Four methods of inspection can be utilized – – Observation Palpation Percussion auscultation

Canned Foods Normal Can Clean appearance Rust free Dent free Stain free Has slightly

Canned Foods Normal Can Clean appearance Rust free Dent free Stain free Has slightly concave ends Sound Seams Leak free Labelled Use by date Abnormal Can Rusty can Dented Bulging (“blown”) Leaking unlabelled

Good can

Good can

Observation Look for rusts, leaks, dents, holes, swelling, soldering defects and presence or absence

Observation Look for rusts, leaks, dents, holes, swelling, soldering defects and presence or absence of labels. CANS WITHOUT LABELS MUST BE CONDEMNED Swollen cans are referred to as “blown” Blowing is due to gas production from microbial action or chemical reaction Check labels or bottom of cans for product dating

Palpation Degrees of swelling can be detected by palpation, i. e. , pressing the

Palpation Degrees of swelling can be detected by palpation, i. e. , pressing the can between the fingers and thumb of both hands. If air is inside, it will respond to pressure. Flipper – earliest stage of spoilage where the can appears normal, but pressure on one end will cause a bulge in the other end. When pressure is release, end regains its normal appearance. Springer – more advanced spoilage where pressure on one end causes the other end to bulge permanently.

Palpation Bulging does not always mean that the contents are decomposing, it may be

Palpation Bulging does not always mean that the contents are decomposing, it may be due to: – Insufficient vacuuming – Overfilling – Chemical reaction between can and food (hydrogen swell) These conditions cannot be determined unless the can is opened, so err on the side of safety and condemn all blown cans.

Percussion Employment of this method provides a useful indication of quality. Sound cans will

Percussion Employment of this method provides a useful indication of quality. Sound cans will emit a dull note when tapped If gas is present in a can, it will have a higher, drum like pitch when knocked

Auscultation This is applicable to canned foods that were not packed with liquid, e.

Auscultation This is applicable to canned foods that were not packed with liquid, e. g. , meats. If the contents have deteriorated, a liquid will be present. DO NOT USE THIS METHOD FOR FOODS PACKED IN LIQUID Canned foods can deteriorate without gas production (flat sour) – This cannot be detected without opening On the basis of the condition of the can, you make your judgment – pass or condemn.

Bad Cans

Bad Cans

Bad Cans A. Bulge or swollen at one or both ends B. Cans dented

Bad Cans A. Bulge or swollen at one or both ends B. Cans dented at seams C. Can showing signs of leaking D. Rusty cans

Assignment Acceptance /rejection criteria for: – Prepare an inspection form to be used at

Assignment Acceptance /rejection criteria for: – Prepare an inspection form to be used at a receival area of a large restaurant. Design the form in a manner such that there are clear acceptance rejection criteria for any food of choice. Due: Next Practical session