Podcast
Questions and Answers
What is the primary benefit of pasteurisation in food processing?
What is the primary benefit of pasteurisation in food processing?
Which method is known for altering the taste of food while reducing moisture content?
Which method is known for altering the taste of food while reducing moisture content?
What is the main function of sugar in food preservation?
What is the main function of sugar in food preservation?
How does smoking preserve food?
How does smoking preserve food?
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What is a disadvantage of the drying method of food preservation?
What is a disadvantage of the drying method of food preservation?
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What impact does vinegar have on food preservation?
What impact does vinegar have on food preservation?
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What does accelerated freeze drying primarily achieve?
What does accelerated freeze drying primarily achieve?
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What is a common result of using high concentrations of salt in food preservation?
What is a common result of using high concentrations of salt in food preservation?
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What factors must be controlled to prevent bacterial growth in food?
What factors must be controlled to prevent bacterial growth in food?
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Which of the following foods is considered high risk for bacterial multiplication?
Which of the following foods is considered high risk for bacterial multiplication?
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What is meant by 'direct contact' in food hygiene?
What is meant by 'direct contact' in food hygiene?
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Which practice best describes indirect contact or cross-contamination?
Which practice best describes indirect contact or cross-contamination?
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Which food item would be classified as low risk for bacterial growth?
Which food item would be classified as low risk for bacterial growth?
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Which characteristic is NOT essential for a food to be classified as a staple food?
Which characteristic is NOT essential for a food to be classified as a staple food?
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Which food item is classified as a plant staple food?
Which food item is classified as a plant staple food?
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What was introduced to Australia by the first fleet in 1788?
What was introduced to Australia by the first fleet in 1788?
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In what decade did American fast food chains first establish locations in Australia?
In what decade did American fast food chains first establish locations in Australia?
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Which group introduced new vegetables and cooking methods to Australia?
Which group introduced new vegetables and cooking methods to Australia?
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Which food was introduced to Australia during the 1940s by American troops?
Which food was introduced to Australia during the 1940s by American troops?
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What event attracted global migration to Australia in the 1850s?
What event attracted global migration to Australia in the 1850s?
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Which food item is NOT considered a meat/animal staple food?
Which food item is NOT considered a meat/animal staple food?
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What is a characteristic of freeze-dried foods compared to dehydrated foods?
What is a characteristic of freeze-dried foods compared to dehydrated foods?
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What occurs to microbes when food is frozen at -18°C?
What occurs to microbes when food is frozen at -18°C?
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Why is vacuum packing important for food preservation?
Why is vacuum packing important for food preservation?
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What is a disadvantage of using sublimation in food storage?
What is a disadvantage of using sublimation in food storage?
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What is the purpose of Modified Atmosphere Packaging (MAP)?
What is the purpose of Modified Atmosphere Packaging (MAP)?
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Which bacteria can survive in vacuum-packed food if not properly handled?
Which bacteria can survive in vacuum-packed food if not properly handled?
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What is a downside of food stored at freezing temperatures for extended periods?
What is a downside of food stored at freezing temperatures for extended periods?
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What must be ensured prior to vacuum sealing food?
What must be ensured prior to vacuum sealing food?
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What role does temperature play in the aeration of egg whites?
What role does temperature play in the aeration of egg whites?
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Which of the following ingredients can stabilize foam during the aeration of egg whites?
Which of the following ingredients can stabilize foam during the aeration of egg whites?
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What effect does adding egg yolk have on foaming?
What effect does adding egg yolk have on foaming?
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What is the primary result of oxidation in meat?
What is the primary result of oxidation in meat?
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How does agitation affect the foaming process?
How does agitation affect the foaming process?
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What happens to myoglobin when it is exposed to air?
What happens to myoglobin when it is exposed to air?
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Which of the following variables can decrease the stability of foam when added?
Which of the following variables can decrease the stability of foam when added?
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What color does meat typically turn to due to the oxidation of myoglobin?
What color does meat typically turn to due to the oxidation of myoglobin?
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Study Notes
Food Preservation Techniques
- Retain Nutritional Value: Freeze-drying retains taste and nutritional benefits, lasting months or years.
- Sublimation Process: Removes moisture without losing structure, unlike dehydration where nutrient loss can occur.
- Freezing Food: Preserves for up to 3 months at -18°C; microbes are not killed but growth is slowed.
- Vacuum Packing: Oxygen removal inhibits bacteria growth; requires clean food to prevent contamination.
- Modified Atmosphere Packaging (MAP): Adds gases to food packaging, slowing spoilage and maintaining color.
- Pasteurization: Heats milk to 72°C for 15 seconds, inactivating enzymes to enhance nutrient absorption.
- Sugar as a Preservative: High sugar concentration dehydrates food, but may lead to loss of vitamins during heating.
- Salting and Curing: Coating food in salt reduces moisture and significantly alters taste.
- Vinegar Use: The acidic nature lowers enzyme activity and inhibits spoilage.
- Smoking Food: Preserves through exposure to smoke but may introduce carcinogens; often not fully cooked.
- Drying Method: Eliminates moisture to hinder bacterial growth but doesn't remove pre-existing toxins.
Food Selection and Availability
- Staple Foods Criteria: Must be readily available, energy-rich, protein source, economically viable, and of plant or animal origin.
- Plant Staples: Include potatoes, rice, wheat, and corn.
- Animal Staples: Include beef, lamb, chicken, barramundi, and salmon.
Historical Changes in Food Availability
- Migration Impact: Each migrant group increased food diversity by introducing familiar foods.
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Timeline of Food Introduction:
- 1788: British foods introduced by the First Fleet.
- 1830s: German immigrants founded vineyards.
- 1850s: Gold rush attracted diverse immigrants.
- 1880s: Italians brought sugar cane expertise.
- 1920s: American cereals like Kellogg’s launched.
- 1940s: WWII American troops introduced fast food culture.
- 1960s-70s: American chains like McDonald's emerged in Australia.
Food Hygiene Practices
- Low-Risk Foods: Bacteria don’t multiply on high sugar or dry foods (e.g., cereals, dried pasta).
- High-Risk Foods: Moist, protein-rich foods can harbor bacteria (e.g., chicken, milk).
- Cross Contamination: Caused by direct (raw meat touching cooked) and indirect contact (contaminated surfaces).
Foam Formation in Cooking
- Foaming Process: Air is incorporated into liquids like egg whites to create structure; influenced by temperature and agitation.
- Stabilizing Foam: Acids (e.g., cream of tartar) and sugar added at the end enhance stability and texture.
Browning in Meat
- Oxidation Reaction: Exposure to oxygen changes meat color from red to brown through myoglobin oxidation.
- Factors Affecting Browning: Heat, freezing, and bacteria can expedite this process, altering meat's appearance.
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Description
This quiz delves into the methods of food preservation, focusing on the process of sublimation and its advantages over dehydration. Explore how these techniques affect the nutritional value and longevity of food, as well as their cost implications.
