Everyday Science - Food Processing and Nutrition MCQs

Correct Answer: Fortification

Fortification is the addition of nutrients that are not naturally present in a food, or present only in small amounts, such as vitamins A and D added to milk.

Correct Answer: Fortification

Iodized salt is the classic example of fortification: iodine is added to salt to prevent iodine-deficiency disorders such as goitre.

Correct Answer: Fortification

Iron is added to flour as a fortificant to combat iron-deficiency anaemia; it is not a nutrient restored after processing, which would be enrichment.

Correct Answer: Enrichment

Enrichment restores nutrients lost during processing (for example B-vitamins lost when grain is milled), whereas fortification adds nutrients beyond the food's original content.

Correct Answer: Fermentation

Lactic-acid bacteria ferment lactose in milk into lactic acid, which thickens the milk into curd (yogurt/dahi).

Correct Answer: Fermentation

In alcoholic fermentation, yeast converts sugars into ethanol and carbon dioxide without oxygen.

Correct Answer: Fermentation

Lactic-acid fermentation by bacteria converts milk sugar (lactose) into lactic acid, the basis of curd, yogurt and cheese-making.

Correct Answer: Pasteurization

Pasteurization heats milk (typically 63-72 C) long enough to kill most disease-causing bacteria; unlike sterilization it does not kill all microorganisms.

Correct Answer: Pasteurization

Pasteurization is named after Louis Pasteur, who showed in the 1860s that heating wine and beer killed the microbes that spoiled them.

Correct Answer: Homogenization

Homogenization forces milk through a narrow gap under pressure, breaking fat globules into tiny droplets so the cream does not separate.

Correct Answer: Vitamin A & D

Milk is commonly fortified with vitamins A and D; vitamin D also helps the body absorb the calcium already present in milk.

Correct Answer: Neural tube defects

Folic-acid fortification of cereals is targeted at preventing neural tube defects (such as spina bifida) in babies born to women of childbearing age.

Correct Answer: Dehydration

Dehydration removes water from food, so bacteria, yeasts and moulds cannot grow; dried fruit, milk powder and dried meat all rely on it.

Correct Answer: Dehydration

Sun-drying removes moisture from fruit by heat and air, a traditional form of dehydration that stops microbial growth.

Correct Answer: UHT processing

UHT (Ultra-High Temperature) processing heats liquid food to about 135-150 C for 2-5 seconds, then packs it aseptically.

Correct Answer: Sterilization

UHT treatment sterilizes milk, destroying heat-resistant spores that survive ordinary pasteurization, which is why UHT milk keeps for months unopened.

Correct Answer: Fermentation

Fermentation uses microorganisms (yeasts, bacteria, moulds) to transform raw food into bread, yogurt, cheese, pickles and alcoholic drinks.

Correct Answer: Fermentation

Cheese-making begins with fermentation: lactic-acid bacteria acidify the milk, after which rennet curdles it.

Correct Answer: Fortification

Calcium is not naturally present in fruit juice at that level, so adding it is fortification, done to give juice the calcium normally obtained from milk.

Correct Answer: Rickets

Vitamin D enables calcium absorption for bone growth; deficiency in children causes rickets (soft, weak bones).

Correct Answer: Anemia

Iron is needed to make haemoglobin; iron fortification of flour and salt combats iron-deficiency anaemia.

Correct Answer: Sterilization

Sterilization destroys or removes all microorganisms, including spores, whereas pasteurization and disinfection only reduce their numbers.

Correct Answer: Curing

Curing preserves meat and fish with salt (sometimes with nitrates), which draws out moisture and inhibits bacterial growth.

Correct Answer: Pickling

Pickling preserves food in vinegar (acetic acid); the acid environment prevents the growth of spoilage organisms.

Correct Answer: Shelf life

Preservatives slow spoilage and microbial growth, so the food stays safe and edible for longer; they do not add nutrients.

Correct Answer: Pasteurization

Pasteurization heats food below boiling point (milk typically 63 C for 30 minutes or 72 C for 15 seconds), killing pathogens without boiling the food.

Correct Answer: Carbon dioxide

Yeast ferments sugars in dough into ethanol and carbon dioxide; the trapped gas makes the dough rise.

Correct Answer: Nutritional value

Fortification adds vitamins or minerals, raising the food's nutritional value; it is a public-health measure, not a flavour or colour treatment.

Correct Answer: Digestibility

Fermentation partly breaks down proteins, lactose and complex carbohydrates, making fermented foods easier to digest.

Correct Answer: Calcium

Vitamin D is required for the intestine to absorb calcium efficiently, which is why milk is fortified with vitamin D alongside its natural calcium.

Correct Answer: Quick freezing

Quick (flash) freezing forms small ice crystals that do less damage to food texture than slow freezing, preserving quality.

Correct Answer: Refrigeration

Refrigeration keeps food at about 0-5 C, slowing bacterial growth and enzyme activity without freezing it.

Correct Answer: Fortification

Probiotic cultures are added to yogurt for their health benefit, which the booklet classes as fortification (a functional-food addition).

Correct Answer: Blanching

Blanching is a brief scalding of vegetables in boiling water or steam that inactivates enzymes before freezing or canning.

Correct Answer: Oxidation

Removing oxygen (for example in vacuum or modified-atmosphere packs) prevents oxidative rancidity and slows aerobic spoilage.

Correct Answer: Fortification

Omega-3 fatty acids are added to milk as a fortificant for heart and brain health; they are not a nutrient lost in milk processing.

Correct Answer: Fermentation

Fermentation is nature's own preservation method: microbes produce acid or alcohol that stops harmful organisms growing.

Correct Answer: Folic acid

Wheat flour is commonly fortified with iron and folic acid together, targeting anaemia and neural tube defects.

Correct Answer: Homogenization

Homogenization breaks fat globules evenly through the milk, giving it a uniform consistency and preventing a cream layer forming on top.

Correct Answer: Alcohol

Vinegar is made in two fermentations: yeast first turns sugar into alcohol, then acetic-acid bacteria convert the alcohol into acetic acid.

Correct Answer: Sugaring

Sugaring preserves fruit (as jams, jellies and candied fruit) because high sugar concentration draws water out of microbial cells.

Correct Answer: Dehydration

Milk powder is made by spray-drying: milk is atomized into hot air so its water evaporates, leaving the dry solids.

Correct Answer: Pasteurization

Pasteurization destroys the vegetative spoilage and pathogenic bacteria in foods such as milk and juice.

Correct Answer: Microorganisms

Fermentation is carried out by microorganisms - yeasts and bacteria - whose enzymes do the chemical conversion.

Correct Answer: Nutrient deficiencies

Fortification adds a missing vitamin or mineral to a staple food specifically to prevent deficiency disease in the population.

Correct Answer: Lactobacillus

Yogurt is made with Lactobacillus (L. delbrueckii subsp. bulgaricus, with Streptococcus thermophilus as co-culture), which ferments lactose to lactic acid.

Correct Answer: Fortification

Zinc is added to staple foods as a fortificant to prevent zinc deficiency, which impairs growth and immunity.

Correct Answer: Canning

Canning seals food in airtight containers (tins or jars) and heats them to destroy spoilage organisms, giving a long shelf life.

Correct Answer: Smoking

Smoking preserves meat and fish: smoke deposits antimicrobial compounds and the drying effect lowers moisture.

Correct Answer: Public health

Fortified staples (iodized salt, fortified flour, fortified milk) are a public-health tool against population-wide nutrient deficiencies.