FOOD3017 Final Exam

Food Safety & Quality Management

Drivers of changing food safety landscape

• Demand for convenience, fresher, healthier and less processed foods

• Innovations in food processing and packaging

• Gloval ingredient sourcing

• Rising expectations from authorities

Challenges for food safety authorities

• rapid growth in food trade and diversity

• new agricultural and manufacturing practices

• emerging hazards and technology

• public demand for health protection

• WTO SPS agreement requiring science based risk assessment

What are the components of risk analysis?

• risk assessment

• risk management

• Risk communication

Why is risk analysis important?

• preferred method of linking food hazards to health risks

• supports decision making weith scientific and stakeholder input

• promotes transparency, consistency and global harmonisation

• facilitates trade and sets control measures

What are the ouputs of risk assessment?

Regulatory

• Standards/enforcement

• documents/guides

• import certificates

• education/training

Industry

• control hazards

• correct processing’

• proper labelling

• recall procedures

What is risk assessment?

• Evaluation of known and potential adverse health effects

• Includes qualitative and quantitative measures

• considers uncertainties and supports health protection decisions

What are the characteristics of risk assessment?

• Objective, transparent, systematic

• based on scientific data

• covers entire food chain

• peer-reviewed and updates with new data

What are sources of scientific information?

• published/unpublished studies

• national monitoring and surveillance data

• international databases (JECFA, JMPR)

• Expert panels and risk asssessments from other countries

What factors affect the risk assessment methodology?

• hazard classs

• hazard characteristics

• scenario

• available methods

What is the risk assesment procedure?

1. Hazard identification

2. Hazard characterisation

3. Exposure assessment

4. Risk characterisation

What is hazard identification?

• Identification of hazard and nature of hazard

What is involved in identification of microbiological hazards?

• identification of infection pathway

• Identify toxins

How does chemical hazard identification differ by history?

No history

• Use toxicology or structure studies

History

• Use existing data or experimental studies

What factors are involved in chemical hazard identification?

• Dose response

  • NOAEL, LOAEL, LD50

• Thresholds

  • Lowest dose with effect

• ARfD - Acute reference dose for short term exposure

What is hazard characterisation?

• Describe nature and extend of health effects

• Establish dose-response relationships

What factors are involved in microbial hazard characterisation?

• food vehicle

• host factors

What is considered in chemical hazard characterisation?

• Determine safe intakes

  • ADI

  • ARfD

  • PTWI

  • PMTDI

What is exposure assessment?

• Track hazard levels through food chain

• Combine consumption and concentration data

  • Adjusted for body weight and compared to health standards

  • Depends on quality of data, purpose and statistical methods

    • Probabilistic

    • Deterministic

What is risk characterisation?

• Integrate hazard and exposure data

• Estimates probability and severity of health effects

• Accounts for uncertainties and population-specific effects

What is involved in microbiological risk characterisation?

Qualitative descriptions

What is involved in chemical risk characterisation?

Margin of safety between intake and hazard

What is a dose response curve?

• mathematical relationship translating number of organisms into probability of adverse outcomes

• experimental and observational data

• limited availability, outliers and widely scattered

What must be accounted for when determining exposure?

• Concentration

• growth

• reduction

• level/amount of food consumed

What is risk management

What is involved in risk management?

• select control methods based on risk assessment

• define appropriate level of protection (ALOP)

• Balances public safety, feasibility, consumer expectations

What are the approaches to risk management?

• Zero Risk

  • negligible exposure levels

• ALARA

  • as low as reasonably achievable

• Threshold

  • below specific numerical limit

• Benefit-cost

  • weigh health benefits vs cost

• Comparative risks

  • Consider trade-offs

• Precautionary

  • Interim measures when data is limited

What are the classes of risk management tools?

• General

• Microbiological

• Chemical

• Setting limits

What are some general risk management tools?

• Standards

• Guidelines

• Education

What are some microbiological management tools?

• HACCP

• Limits

• Surveys

What are some chemical risk management tools?

• Prohibit

• restrict

• label

• educate

What are some limits that can be used in risk management?

• MRLs

  • Maximum residue limit

  • For agriculture/vetinary residues

• MLs

  • Maximum limit

  • For contaminants

What is risk communication?

• Interactive exhange amongst assessors, management and general public

• explains risks, control measures and scientific basis

What are some risk communication activities

• workshops

• forums

• consultations

• public documents

• media

• education

What is root cause analysis?

Tool used to identify underlying cause(s) of problem or incident

• immediate cause

• underlying cause that contributed

Why is root cause analysis important?

• preventing reccurence

• continuous improvement

• informed decision making

What are the types of incidents that could trigger root cause analysis?

• food safety incident

  • consumer health at risk

  • food safety standard contravened

• regulatory incident

  • regulatory requirement not met

  • however, no safety risk

• quality incident

  • doesn’t impact safety but impacts suitability

  • economic consequences

What is a contributing factor in root cause analysis?

Specific environmental, biological, procedural, attitudinal or behavioural factors that directly resulted in failure. What went wrong, not why.

What are the steps of root cause analysis?

1. Problem statement

2. Collect information and data

3. Investigate and analysis

   1. identify implicated products and processes and identify all possible root causes

4. Determine preventative/corrective strategies

5. Implement and validate strategies

6. Review

What are some root cause analysis tools?

• 5 Whys

• Fishbone/Ishikawa Diagram

• Pareto charts

What is involved in the 5 Whys?

• Ask why five times to distinguish symptoms from root cause

• not set at five…

What is involved in the fishbone/ishikawa diagram?

• head is problem

• bones represent causes of problem

What is involved in a pareto chart analysis?

• 80:20 principle

• vital few, trivial many

• focus on major issues rather than minor causes

What are the most common causes in root cause analysis?

• management failures

• production and process control failures

• personnel failures

What are the benefits of root cause analysis?

• Prevent future recalls

• prevent outbreaks

• strengthen continuous improvement processes

• provide evidence of commitment to supply chain partners

• nurture employee pride

• enhance organisational culture

What is validation?

Evidence that control measures or combination of control measures, if properly implemented, is capable of controlling the hazard to a specific outcome.

What are the types of validation?

• Process (validate CCP)

• Shelf-life

• Cleaning (allergen)

What is the purpose of validation?

• Demonstrate controls are effectve in reducing risk to public health

• Regulatory agencies & certification bodies

• Customers expect validated procedures

• Requirements for many standards

What are the types of validation tools?

• Historically recognised processes

• Published documents

• Scientifically valid data (in-house/provider)

• Microbiological modelling

• Challenge studies

What are the considerations when using microbiological modelling?

• requires data

• validity for food in question

• be conservative!

What are the pre-validation steps?

• Identify hazards or pathogens

• Identify outcome required

• identify measures required

What are the steps of validation?

• Decide approach

• Identify equipment and parameters

• Define critical limits

• Assemble values and studies

• Analyse results

• Document

What are the considerations for allergen cleaning?

• Must be validated

• Review process, ingredients and equipment

• Describe frequency, process, schedule of cleaning

• Identify sampling sites and swab to verify

What are the limits of HPP in validation?

• highly variable impact

• depnds on species, pressure, processing time, temp, etc.

What are phytochemicals?

• Non-nutritive chemical compounds produced by plants

• Not necessarily toxic, most neutral, some protective

• Can have beneficial or adverse biological effects

What are phytotoxins?

• Subset of phytochemicals

• toxic to humans at sufficient dose

What are risk factors of phytotoxins?

• Usually low level

• High risk scenarios

  • low variety diet

  • poor preparation or processing

  • impairment of nutrient absorption

  • individual susceptibility to effects of phytotoxin

What are the main classes of phytotoxins?

• Cyanogenic glycosides

• Alkaloids

• Lectins

• Antinutrients

• Goitrogens

What are cyanogenic glycosides?

• Sugar attached to cyanide containing group

• damage to tissue allows enzyme to create hydrogen cyanide (HCN)

• Found in 2500+ species

  • tubers, legumes, sorghum, nuts, stonefruit pits, bamboo shoots

• Cycads in aboriginal foods, removed by washing and fermentation

What is the mechanism for cyanogenic glycosides?

• Physical damage releases HCN

• HCN inhibits cytochrome oxidase (last stage of electron transport chain)

• Blocks cellular respiration

• Rapid onset toxicity

What can be done to reduce the effect of cyanogenic glycosides?

• Chopping/grinding (releases HCN to air)

• Fermentation (Enzymes and microbes break down HCN)

• Washing (physical removal)

What are alkaloids?

• Nitrogen containing heterocyclic ring compounds

• Wide range of biological effects and activity

What are the two main types of alkaloids?

• Pyrrolizidine alkaloids

• Glycoalkaloids

What are some sources of pyrrolizidine alkaloids?

Direct

• Herbal teas, weeds, seeds

Indirect

• Honey, milk, eggs

What is the mechanism for pyrrolizidine alkaloids?

Acute

• Presents as liver failure

Chronic

• Abdominal pain, ascites

• Late manifestation of hepatic failure

• Recoery if intake stopped

What are sources of glycoalkaloids?

• Tomatoes

• Eggplants

• Potatoes

• Kangaroo apples (unripe)

What are the characteristics of glycoalkaloids?

• Heat stable

• Produced when plant/vegetable under stress (solanine)

What is the mechanism of glycoalkaloids?

Acute

• Nausea, diarrhoea, vomiting

• High dose

  • Halliucinations, paralysis, respiratory failure

What are lectins?

• Carbohydrate binded glycoproteins

• Raw/uncooked material

What are the sources of lectins?

Raw

• Legumes

• Wholegrains

What is the mechanism and outcomes for lectins?

• Bind carbohydrate groups on surface of gut epithelial cells

  • inhibits membrane repair pathogens

  • leads to cell death, GI symptoms, reduced nutrient absorption

Explain toxicity caused by kidney beans

• High PHA levels

• 4-5 can have severe GI symptoms

  • cramps, diarrhoea, vomiting

• 1-3 hr onset

• slow cooking can increase availability

• pre-soak, 100C+ cooking

What are antinutrients?

• Phytochemicals that interfere with nutrient bioavailability and absorption

• Reduce through preparation

What are three types of antinutrients?

• Oxalates

• Tannins

• Phytic acid (phytates)

What is the mechanism of oxalates?

• Oxalic acid binds calcium to find calicum oxalate (insoluble)

• Crystals can accumulate in kidneys

• people with prior stones or low calcium at risk

What are the sources of oxalates?

• spinach

• chocolate

• tea

• nuts

• rhubarb leaves

What are some characteristics of oxalates?

• heat stable

• water soluble

What is the mechanism of tannins?

• bind non-haem iron

• bind dietary protein

• inhibit digestion

• interfere with enzymes

What are some sources of tannins?

• Tea

• Coffee

• Chocolate

• Wine

How can antinutrient activity of tannins be limited?

• Limit consumption with other foods

• eg. tea with iron rich meat

• high risk for those with low iron

What is phytic acid (phytate)?

• phosphorous storage in plants, cereals, legumes, nuts

What is the mechanism of phytic acid?

Chelates essential minerals, prevents absorption

How can the antinutrient effects of phytic acid be limited?

• heat alone ineffective

• Activate phytase

  • germination

  • soaking

  • fermentation

What is the mechanism of goitrogens?

• Interfere wiith thyroid hormone synthesis

• Reduces iodine reaching or being used by thyroid

• Iodine needed for T3 and T4 hormones

  • stimulates TSH production, gland works harder, enlarges (goitre)

Chronic

• hypothyroidism

• impaired neurodevelopment

No problem with normal iodine intake

What are sources of goitrogens?

brassica (cabbage, broccoli, mustard)

Explain risk-benefit in context of phytotoxins

• foods contain many important nutrients and phytochemicals

• generally high benefit, low risk

What are risk factors of

Explain risk-benefit using caffeine as an example?

Benefits

• Alertness

• focus

• physical performance

Risks

• Addictive

• headache/nausea

• Sleep disruption

• Pregnancy outcomes

What are mycotoxins and their characteristics?

• Toxic secondary metabolites produced by fungi that contaminate food crops

• non-protein, non-carbohydrate low molecular weight chemical structures

• persist beyond cooking and processing

• Often Invisible and odourless

What factors affect mycotoxin formation?

• Warm temperatures

• high water activity

• poor storage

What foods are commonly affected by mycotoxins?

• cereals (maize, rice wheat)

• nuts, oil seeds

• spices

• coffee

• animal products (carry-over)

How do mycotoxins reach people?

• Eating contaminated crops

• Carry-over through animals

• Hidden methods

How do mycotoxins carry-over through animals?

• Dairy cattle eat contaminated feed

• Toxin converts and appears in milk

• B1 alfatoxin in feed to M1 in milk

What are hidden methods in mycotoxin exposure?

• Plant attaches sugar to toxin for defence

  • gut strips sugar off, releasing toxin

• Grain handlers inhaling contaminated dust

What is acute exposure for mycotoxins?

• short-term, high dose

• once over hours to days

• rare/uncommon but severe

• sudden vomiting (deoxynivalenol)

• Acute liver failure for alfatoxins

What is chronic exposure for mycotoxins?

• repeated low-dose exposure

• months to years

• no immediate symptoms

• major contributor to disease burden

• Focus on

  • Tolerable daily intake (TDI)

  • Daily exposure over lifetime

  • long-term exposure assessment

What are some mycotoxin groups?

• Fumonisin

• Deoxynivralenol (DON)

• Alfatoxins

What are the characteristics of fumonisins?

• Toxins produced by Fusarium species

• Primarily contaminate corn

• Structurally like sphingolipids

What is the mechanism of fumonisins?

• Resemble sphingolipids (building blocks for cell membrane)

• Blocks cell assembly (ceramide synthase)

• Sphinganine builds up in cells

• Inhibits construction of membranes

• affects cell signalling, apoptosis

How can fumonisins cause animal toxicity?

• fatal brain damge in horses

• fluids in lungs in pigs

• redued growth in poultry

• rodents, liver cancer, kidney damage