Food technology Flashcards
What are the intrinsic factors in food microbiology
Intrinsic factors are properties of the food itself that affect microbial growth, including nutrient content, pH, redox potential, water activity, natural antimicrobials, and mechanical barriers.
Why is water activity (aw) important in food preservation
Water activity measures how efficiently water can participate in chemical or biological reactions.
Lowering aw reduces microbial growth and is a key method of preservation (e.g., drying, salting).
What is food technology?
Food technology is the study of how different foods can be used and made into food products from production to consumption
What is food chain management?
Food chain management involves the management of all activities involved in the production, transformation, storage, distribution and the holistic farm to table approach.
What is the main aim of food preservation
What is food processing
What is the role of the vet in food technology
Inspection of animal origin food establishments.
Microbiological testing.
Legislation.
name some natural antimicrobial substances
What do microorganisms of importance to food require to grow and function normally
How does pH influence microbial growth?
Most microorganisms grow best at pH 6.6–7.5.
Foods with low pH (<4.0), like pickles, inhibit many spoilage microorganisms.
Buffered foods tend to resist changes in pH (meats are more highly buffered than vegetables due to their various proteins).
What is the significance of redox potential (Eh) in microbial growth?
Eh measures the ability of a substrate to gain or lose electrons.
Aerobic microbes require positive Eh (oxidized), while anaerobes need negative Eh (reduced).
What is thermal processing of 1D-4D
What determines oxidation/reduction?
The characteristic O/R potential of the original food.
The poising capacity; that is, the resistance to change in potential of the food.
The oxygen tension of the atmosphere around the food.
The access that the atmosphere has to the food.
Microorganisms affect the Eh of their environments during growth just as they do pH.
What is a mechanical barrier for microbial invasion
skin
e.g. fermented meat products
What is the D value in thermal processing?
The D-value is the time required to kill 90% of a microbial population at a specific temperature.
What are extrinsic factors in food microbiology
Extrinsic factors are environmental factors that influence microbial growth, including temperature, humidity, atmosphere, and storage time.
What is the ideal temperature for Psychrotrophs, Psycrophiles, Mesophiles and Thermophiles?
What is the Z value in thermal processing?
The Z-value is the temperature change needed to alter the D-value by a factor of 10.
How does Modified Atmosphere Packaging (MAP) inhibit microbial growth?
MAP uses gases like carbon dioxide (CO₂) to inhibit microbial growth by creating unfavorable conditions.
Why is relative humidity important in food storage?
Low relative humidity prevents surface spoilage by moulds, yeasts, and bacteria, while high humidity can promote microbial growth.
What is food spoilage?
Food spoilage refers to changes in food making it unacceptable to consumers due to smell, taste, appearance, or texture.
Why is food rejected as spoiled?