Week 8 Flashcards
Sanisters (external treatments)
Reduced bacteria on surface
- Stop cross contamination by killing most of the bacteria that was off into solution
If the water does not contain an active sanitiser, it is possible that cross contamination of the whole batch can occur
- Chlorine based (pH must be monitored) - PAA
- Organic
- Gas-based
- Electrolysed oxidising water
Food preservation/protection
- Essential fresh foods remain safe and unspoiled - methods:
1. sterilisation/pasteurisation by heat or radiation to reduce microbial load 2. Temperature control by refrigeration/freezing reduces or stops activity of
microorganisms
3. Drying reduces or stops the activity of the microorganism by removing
essential water
4. Restricting oxygen by modifying or controlling gas atmosphere
5. Chemical preservatives reduce or inhibit activity of microorganisms
Drying
- Sorption isotherm → the relationship between water activity and moisture content at a given temperature - Unique for each product due to different interactions
between water and the solid components - Lowest aw at which the majority of spoilage will frow is 0.9 - The aw for moulds and yeast is 0.61
Salting
- Inhibition of spoilage due to Cl- and lowein=ring water activity
Weak organic acids (chemical preservative)
- Increase acid environment
- Na and Ca mould inhibitor
Nitrates (chemical preservative)
Na and K salts curing agents of meat
Chelating agents
Chelating agents
- Citric acid which is a metal ion where enzymes need to function
Sulfites
- Inhibit microbial growth through inhibition of ATP, some metabolic pathways and block cellular transport systems
- Also reduce enzymatic and non enzymatic browning
- Dried apricots
Non chemical antimicrobial treatments
- Many technologies present potential alternative controls but are not (yet) in common use either due to expense, lack of consumer acceptance, or need for more research:
- High pressure - Irradiation
Packaging
- Containment of food
- Preserving food against spoilage - Extending shelf life
- Protection from contaminants
- Information
- Utility.convinience
Types of packaging
Primary
- Container in direct contact with the food
Secondary
- Container that holds several primary units
Tertiary
- Container holds several secondary units
packaging materials
- Metal (aluminium and steel)
- Forms hermetic seal, oxygen and light barrier, recyclable, strong
- Glass (food visible)
- Has to withstand pressure
- Paper (one layer or more)
- May be fortified with additives to give strength, leak protective and tear
resistance - Plastic (flexible, lightweight, sealable,)
Sustainable nutrition
- On pack sustainability claims have increased in line with consumer’s desire for more eco-focused brands
- Addressing food waste is crucial for achieving sustainable food systems, as it saves resources, reduces impact and helps alleviate food insecurity
Gut health
fibre is key
Plant protein
- The health benefits of legumes relate to their inclusion in dietary patterns where plant-based protein is prioritised.
- Lower heart disease, diabetes, cancers
- Improves weight management, gut microbiome, mental, sustainable eating
- Many are claiming plant based
