General Science One Liners for Competitive Exams 2026

Everyday Science one liner - Health, Hygiene, Nutrition and Food Science

1. Human Nutrition and Nutrients

• What is the chemical name of fat-soluble Vitamin A? - Retinol
• Which eye condition causing poor vision in dim light is caused by Vitamin A deficiency? - Night Blindness (Nyctalopia)
• What is the severe drying and keratinization of the cornea due to Vitamin A deficiency called? - Xerophthalmia
• What are the small, foamy, grayish-white spots on the conjunctiva from Vitamin A deficiency called? - Bitot's Spots
• What is the plant precursor of Vitamin A found in yellow and orange vegetables? - Beta-Carotene
• What is the chemical name of Vitamin B1? - Thiamine
• Which nervous system and cardiovascular disorder is caused by a deficiency of Vitamin B1? - Beriberi
• What is the dry form of beriberi primarily characterized by? - Peripheral Neuropathy and Muscle Wasting
• What is the wet form of beriberi primarily characterized by? - Cardiomegaly and Edema
• What is the chemical name of Vitamin B2? - Riboflavin
• Which condition causing painful fissures at the corners of the mouth is linked to Vitamin B2 deficiency? - Cheilosis (Angular Stomatitis)
• What is the chemical name of Vitamin B3? - Niacin (Nicotinic Acid)
• Which disease characterized by the 3 Ds (Diarrhea, Dermatitis, and Dementia) results from Vitamin B3 deficiency? - Pellagra
• Which essential amino acid serves as a biological precursor for the synthesis of Niacin? - Tryptophan
• What is the chemical name of Vitamin B5? - Pantothenic Acid
• What is the chemical name of Vitamin B6? - Pyridoxine
• What is the chemical name of Vitamin B7 (often called Vitamin H)? - Biotin
• What is the chemical name of Vitamin B9, vital for DNA synthesis and fetal neural tube closure? - Folic Acid (Folate)
• A dietary deficiency of Folic Acid during early pregnancy increases the risk of what birth defect? - Neural Tube Defects (Spina Bifida)
• What is the chemical name of Vitamin B12, containing the central metal ion Cobalt? - Cyanocobalamin
• Which hematological disorder results from a lack of Vitamin B12 or intrinsic factor? - Pernicious Anemia
• What glycoprotein secreted by stomach parietal cells is mandatory for Vitamin B12 absorption? - Intrinsic Factor
• What is the chemical name of water-soluble Vitamin C? - Ascorbic Acid
• Which nutritional disorder characterized by bleeding gums and petechial hemorrhages is caused by Vitamin C deficiency? - Scurvy
• Why is Vitamin C rapidly destroyed during the prolonged boiling or overcooking of food? - It is heat-labile (thermolabile)
• What structural protein's synthesis requires Vitamin C as a cofactor for proline hydroxylation? - Collagen
• What is the chemical name of Vitamin D3 synthesized in the skin under ultraviolet light? - Cholecalciferol
• What disease causing soft, deformed, and bowed bones in growing children is caused by a lack of Vitamin D? - Rickets
• What is the adult equivalent of bone softening caused by severe Vitamin D and calcium depletion called? - Osteomalacia
• What is the active hormonal form of Vitamin D synthesized in the kidneys? - Calcitriol (1,25-dihydroxycholecalciferol)
• What is the chemical name of Vitamin E, which acts as a major lipid-soluble cellular antioxidant? - Tocopherol
• Which vitamin deficiency is associated with erythrocyte hemolysis and reduced reproductive fertility? - Vitamin E
• What is the chemical name of plant-derived Vitamin K1 essential for hepatic clotting factor synthesis? - Phylloquinone
• Which essential blood-clotting factors are dependent on Vitamin K for carboxylation? - Factors II (Prothrombin), VII, IX, and X
• What clinical manifestation is the hallmark of severe Vitamin K deficiency? - Defective Blood Clotting and Spontaneous Hemorrhage
• Which four vitamins are classified as fat-soluble? - Vitamins A, D, E, and K
• Which vitamins are classified as water-soluble? - Vitamin B-Complex and Vitamin C
• What is the primary storage polysaccharide of carbohydrates in the human liver and muscles? - Glycogen
• What simple monosaccharide serves as the immediate respiratory metabolic fuel for brain cells? - Glucose
• What milk disaccharide sugar is composed of one glucose unit and one galactose unit? - Lactose
• What table disaccharide sugar is composed of one glucose molecule and one fructose molecule? - Sucrose
• What is the sweetest naturally occurring monosaccharide found in fruits and honey? - Fructose
• What are the fundamental structural monomer units that link via peptide bonds to form proteins? - Amino Acids
• How many standard amino acids are required by the human body to build functional proteins? - 20
• How many amino acids are classified as nutritionally 'Essential' for adult humans? - 9
• What severe childhood protein deficiency is marked by muscle wasting, edema, and a protruding belly? - Kwashiorkor
• What severe starvation state results from a simultaneous deficit of both protein and total caloric energy? - Marasmus
• How much metabolic energy is yielded by the complete physiological oxidation of 1 gram of fat? - 9 kcal/g
• How much metabolic energy is yielded by the physiological oxidation of 1 gram of carbohydrate or protein? - 4 kcal/g
• What are the structural monomers formed when neutral dietary fats (triglycerides) are fully digested? - Fatty Acids and Glycerol
• What essential omega-3 fatty acid is found in flaxseeds, walnuts, and fatty cold-water fish? - Alpha-Linolenic Acid (ALA)
• What essential omega-6 fatty acid is abundant in sunflower, safflower, and corn oils? - Linoleic Acid
• Which essential trace mineral forms the central oxygen-binding core of blood hemoglobin and myoglobin? - Iron (Fe)
• What nutritional condition results from a chronic dietary deficiency of bioavailable iron? - Iron Deficiency Anemia (Microcytic Hypochromic)
• What dietary acid significantly enhances the non-heme iron absorption from plant foods in the gut? - Ascorbic Acid (Vitamin C)
• Which mineral is required by the follicular cells of the thyroid gland to synthesize thyroxine? - Iodine (I)
• What is the abnormal compensatory enlargement of the thyroid gland due to iodine deficiency called? - Simple Endemic Goitre
• What severe congenital condition of cognitive disability and stunted growth is caused by maternal iodine deficiency? - Cretinism
• Which two minerals constitute the primary structural hydroxyapatite crystal matrix of bones and teeth? - Calcium (Ca) and Phosphorus (P)
• What age-related progressive metabolic bone disease is characterized by low bone mass and fragility fractures? - Osteoporosis
• What trace mineral is required as a cofactor for the antioxidant enzyme Superoxide Dismutase and insulin storage? - Zinc (Zn)
• A nutritional deficiency of Zinc is clinically associated with what sensory and healing impairments? - Loss of Taste (Hypogeusia), Hypogonadism, and Delayed Wound Healing
• What trace element is incorporated into the antioxidant enzyme Glutathione Peroxidase? - Selenium (Se)
• What trace mineral protects dental enamel against acid decay at optimal concentrations? - Fluorine (Fluoride)
• What dental and skeletal condition is caused by drinking water with excess fluoride (>1.5 ppm)? - Fluorosis (Mottled Enamel)
• What non-digestible complex plant carbohydrates provide dietary bulk and promote gastrointestinal motility? - Dietary Fiber (Roughage)
• What physiological parameter reflects the baseline minimum energy expenditure required to sustain vital life at rest? - Basal Metabolic Rate (BMR)
• What clinical anthropometric index is calculated as weight in kilograms divided by height in meters squared? - Body Mass Index (BMI)
• According to standard WHO classification, what BMI range defines normal healthy weight in adults? - 18.5 to 24.9 kg/m²
• What BMI threshold defines clinical Overweight status? - 25.0 to 29.9 kg/m²
• What BMI threshold officially defines clinical Class-I Obesity? - 30.0 kg/m² or higher
• What is the physiological measure of how rapidly a carbohydrate food raises blood glucose levels called? - Glycemic Index (GI)
• What non-nutritive plant compounds found in whole grains and legumes bind minerals and inhibit their absorption? - Phytates (Phytic Acid)
• What compounds present in tea and spinach bind dietary iron and calcium, reducing bioavailability? - Tannins and Oxalates
• What is the recommended daily intake of iodized table salt for an adult to prevent hypertension? - Less than 5 grams per day (<2,000 mg Sodium)
• What is a complete dietary protein that contains all 9 essential amino acids in correct proportions called? - First-Class / High Biological Value Protein (e.g., Egg, Milk)
• What standard reference protein is assigned a Biological Value (BV) score of nearly 100? - Whole Egg Protein (Ovalbumin)
• What primary limiting essential amino acid is deficient in most cereal grains (wheat, rice)? - Lysine
• What primary limiting essential sulfur-containing amino acid is deficient in most pulses and legumes? - Methionine
• What culinary strategy combines cereals and pulses to overcome mutual limiting amino acid deficiencies? - Protein Complementarity
• What golden-colored first milk secreted by lactating mothers is rich in maternal antibodies? - Colostrum
• What predominant protective immunoglobulin isotype is passed to the infant through colostrum? - Secretory Immunoglobulin A (sIgA)
• Up to what minimum age does the WHO recommend exclusive breastfeeding for infants? - 6 Months
• What process involves introducing semi-solid nutritious foods alongside breast milk after 6 months? - Complementary Feeding (Weaning)
• What is the medical term for severe acute dehydration caused by insufficient fluid intake or watery diarrhea? - Hypovolemia
• What glucose-electrolyte solution is the WHO standard formula for treating acute diarrheal dehydration? - Oral Rehydration Salts (ORS)
• What is the concentration of anhydrous Glucose present in standard WHO-reduced osmolarity ORS per liter? - 13.5 grams/L
• What is the concentration of Sodium Chloride present in standard WHO-reduced osmolarity ORS per liter? - 2.6 grams/L
• What trace mineral supplement is co-administered with ORS to reduce the duration and recurrence of childhood diarrhea? - Zinc
• What is a diet containing all essential macro- and micronutrients in proper proportions called? - Balanced Diet
• What toxic natural alkaloid found in green-sprouted potato tubers can cause gastrointestinal toxicity? - Solanine
• What toxic glycoside present in improperly processed cassava tubers yields hydrocyanic acid? - Linamarin (Cyanogenic Glycoside)
• What toxic non-protein amino acid present in Lathyrus sativus (Khesari Dal) causes spastic paralysis of legs? - ODAP / BOAA (Beta-N-oxalyl-alpha,beta-diaminopropionic acid)
• What crippling neuro-paralytic condition is caused by chronic, heavy consumption of Khesari Dal? - Neurolathyrism
• What fungal mycotoxin produced by Aspergillus flavus in improperly stored peanuts is a potent liver carcinogen? - Aflatoxin
• What toxic adulterant oil containing sanguinarine is mixed with edible mustard oil, causing Epidemic Dropsy? - Argemone Oil
• What toxic non-permitted dye is added to turmeric powder to impart a bright yellow color? - Lead Chromate / Metanil Yellow
• What industrial green chemical dye is illicitly used to make green vegetables like peas and chilies appear fresh? - Malachite Green
• What test detects adulteration of starch in milk samples? - Iodine Test (produces a deep blue color)
• What is the process of deliberately adding essential micronutrients to staple foods during industrial processing called? - Food Fortification

2. Public Health, Hygiene and Human Diseases

• How does the World Health Organization (WHO) define Health? - A state of complete physical, mental, and social well-being, and not merely the absence of disease
• On which date is 'World Health Day' celebrated annually to mark the founding of the WHO in 1948? - April 7
• What term describes a disease constantly present at a baseline level within a specific geographic region? - Endemic Disease
• What term describes a sudden, rapid outbreak of a disease affecting many individuals within a localized population? - Epidemic Disease
• What term describes an epidemic that has spread across multiple international borders and continents? - Pandemic Disease
• What is the time interval between the initial entry of a pathogen into a host and the first appearance of clinical symptoms called? - Incubation Period
• What is an individual who harbors and sheds a pathogen without exhibiting active clinical disease symptoms called? - Asymptomatic Carrier
• What was the pseudonym of Mary Mallon, a notorious asymptomatic carrier of typhoid in the early 20th century? - Typhoid Mary
• What are infectious diseases naturally transmissible between vertebrate animals and humans called? - Zoonoses (Zoonotic Diseases)
• What protozoan parasite causes Malaria in humans? - Plasmodium (e.g., Plasmodium falciparum, P. vivax)
• Which biological vector transmits the human malaria parasite between hosts? - Infected Female Anopheles Mosquito
• In which organ of the human host does the malaria parasite undergo initial exo-erythrocytic schizogony? - Liver
• What toxic crystalline pigment released upon RBC rupture causes the periodic shivering chills and fever in malaria? - Hemozoin
• Which mosquito vector transmits viral arboviruses including Dengue, Chikungunya, Yellow Fever, and Zika? - Female Aedes aegypti Mosquito
• What distinct physical morphological feature characterizes the adult Aedes aegypti mosquito? - Black-and-White Striped Markings on Legs and Body (Tiger Mosquito)
• At what time of day does the Aedes aegypti mosquito primarily feed and bite humans? - Daytime (Early morning and late afternoon)
• What critical hematological parameter drops precipitously in severe cases of Dengue Hemorrhagic Fever? - Blood Platelet Count (Thrombocytopenia)
• Which mosquito vector transmits Wuchereria bancrofti, the lymphatic filarial parasite causing Elephantiasis? - Female Culex Mosquito
• What parasitic protozoan transmitted by the Phlebotomine Sandfly causes Visceral Leishmaniasis? - Leishmania donovani (Kala-Azar)
• What flagellated protozoan transmitted by the Tsetse fly causes African Human Trypanosomiasis? - Trypanosoma brucei (Sleeping Sickness)
• What enteric bacterium causes acute watery 'rice-water' diarrhea and massive dehydration? - Vibrio cholerae
• What rod-shaped bacterium causes human Typhoid (Enteric) fever? - Salmonella Typhi
• What clinical serological diagnostic test confirms Typhoid infection by detecting agglutinating antibodies? - Widal Test
• What acid-fast bacillus causes pulmonary and extra-pulmonary Tuberculosis (TB)? - Mycobacterium tuberculosis
• What standard diagnostic intradermal skin test assesses delayed hypersensitivity to tuberculin purified protein? - Mantoux Test (Tuberculin Skin Test)
• What standardized directly observed regimen is advocated globally by the WHO for treating Tuberculosis? - DOTS (Directly Observed Treatment, Short-course)
• What live-attenuated bacterial vaccine provides protective pediatric immunization against severe Tuberculosis? - BCG Vaccine (Bacillus Calmette-Guérin)
• What bacterium causes human Diphtheria by forming a pseudomembrane across the upper pharynx? - Corynebacterium diphtheriae
• What anaerobic, endospore-forming bacterium causes muscular rigidity, lockjaw, and spasms in Tetanus? - Clostridium tetani
• What potent neurotoxin produced by Clostridium tetani blocks inhibitory neurotransmitter release in the spinal cord? - Tetanospasmin
• What combination pediatric vaccine confers protective immunization against Diphtheria, Pertussis, and Tetanus? - DPT Vaccine (Triple Antigen)
• What is the causative bacterium of Pertussis (Whooping Cough)? - Bordetella pertussis
• What fatal neurotropic Rhabdovirus is transmitted to humans via the bite or scratch of rabid mammals? - Rabies Virus (Lyssavirus)
• What pathognomonic clinical fear of swallowing liquids develops in advanced human rabies infection? - Hydrophobia
• What microscopic eosinophilic inclusion bodies found in cerebellar Purkinje neurons confirm rabies diagnosis? - Negri Bodies
• What single-stranded enveloped RNA retrovirus attacks human $\text{CD4}^+$ T-helper lymphocytes, causing AIDS? - Human Immunodeficiency Virus (HIV)
• What enzyme converts viral RNA into double-stranded DNA inside the host cell during retroviral replication? - Reverse Transcriptase
• What is the primary serological enzyme immunoassay used for diagnostic screening of HIV antibodies? - ELISA (Enzyme-Linked Immunosorbent Assay)
• What therapeutic regimen combination is universally prescribed to suppress HIV viral replication? - Antiretroviral Therapy (ART)
• On which date is 'World AIDS Day' observed globally every year? - December 1
• Which enterovirus infects and destroys anterior horn motor neurons of the spinal cord, causing flaccid paralysis? - Poliovirus
• Who developed the first formalin-inactivated injectable Polio vaccine (IPV) in 1952? - Jonas Salk
• Who developed the live-attenuated trivalent Oral Polio Vaccine (OPV) administered as oral drops in 1961? - Albert Sabin
• Which fatal infectious viral orthopoxvirus was certified as globally eradicated in 1980 through universal vaccination? - Smallpox (Variola Virus)
• Who pioneered the smallpox vaccine in 1796 using cowpox pustular exudate, founding immunology? - Edward Jenner
• Who established the Germ Theory of Disease, developed rabies vaccination, and invented pasteurization? - Louis Pasteur
• Who discovered the first clinical antibiotic, Penicillin, from Penicillium notatum molds in 1928? - Alexander Fleming
• Who formulated the definitive Postulates of Disease Causation and identified the etiologic agents of Anthrax and TB? - Robert Koch
• What superficial fungal skin infection is characterized by pruritic, circular, erythematous scaling lesions? - Ringworm (Tinea / Dermatophytosis)
• What fungal species causes the pruritic foot maceration known as 'Athlete's Foot'? - Trichophyton rubrum (Tinea Pedis)
• What opportunistic fungal infection of oral and vaginal mucous membranes is caused by Candida albicans? - Candidiasis (Thrush)
• What sexually transmitted bacterium causes Syphilis, presenting with a painless hard genital ulcer? - Treponema pallidum
• What sexually transmitted diplococcal bacterium causes Gonorrhea, causing purulent urethritis? - Neisseria gonorrhoeae
• What paramyxovirus infection causes painful bilateral swelling and inflammation of the parotid salivary glands? - Mumps
• What highly contagious viral exanthem marked by Koplik's spots on the buccal mucosa is prevented by the MMR vaccine? - Measles (Rubeola)
• What bacterial respiratory infection causes acute consolidation of pulmonary alveoli with inflammatory exudate? - Pneumonia (Streptococcus pneumoniae)
• What chronic bacterial mycobacterial infection causes peripheral nerve thickening, skin hypopigmentation, and anesthesia? - Leprosy (Hansen's Disease / Mycobacterium leprae)
• On which date is 'World Tuberculosis Day' commemorated globally every year? - March 24
• What is the immunity acquired when an individual's own immune system generates antibodies and memory cells? - Active Immunity
• What is the temporary immunity acquired by receiving preformed exogenous antibodies (e.g., Anti-Tetanus Serum)? - Passive Immunity
• What is the only class of maternal immunoglobulins capable of crossing the placenta to protect the fetus? - Immunoglobulin G (IgG)
• What immunoglobulin isotype mediates acute Type-I allergic reactions and antiparasitic responses? - Immunoglobulin E (IgE)
• What potent inflammatory amine released by tissue mast cells and basophils triggers bronchoconstriction and hives? - Histamine
• What condition occurs when the immune system fails self-tolerance and mounts an immune response against host tissues? - Autoimmune Disease
• Name a classic systemic autoimmune disease that causes progressive inflammatory destruction of synovial joints. - Rheumatoid Arthritis
• What autoimmune disorder involves autoantibodies directed against pancreatic islet beta cells, halting insulin production? - Type 1 Diabetes Mellitus
• What public health phenomenon protects unimmunized individuals when a critical threshold of the population is immune? - Herd Immunity
• What is the minimum recommended duration for washing hands thoroughly with soap and water according to WHO guidelines? - At least 20 Seconds
• What is the optimal concentration of ethyl alcohol or isopropanol in hospital-grade hand sanitizer rubs? - 60% to 80%
• What halogen chemical compound is universally used to disinfect municipal drinking water networks? - Chlorine / Sodium Hypochlorite
• What physical water purification process forces pressurized water through a semipermeable membrane to reject dissolved ions? - Reverse Osmosis (RO)
• What physical sterilization method uses pressurized saturated steam at 121°C for 15 minutes to destroy all microbes? - Autoclaving (Moist Heat Sterilization)
• What high-energy radiation is used in germicidal lamps to disrupt microbial DNA in operating rooms and cleanrooms? - Ultraviolet-C (UV-C) Light
• What heavy metal toxicity caused by methylmercury-contaminated industrial effluent was discovered in Minamata Bay? - Minamata Disease
• What painful skeletal and renal tubular disease is caused by chronic environmental Cadmium poisoning? - Itai-Itai (Ouch-Ouch) Disease
• What pediatric condition is caused by high nitrate concentrations in drinking water, impairing hemoglobin oxygen transport? - Blue Baby Syndrome (Methemoglobinemia)
• What chronic dermatological toxicity and peripheral vascular disease is caused by arsenic in groundwater? - Blackfoot Disease (Arsenicosis)
• What is the standard national color coding for biomedical waste bags designated for discarding anatomical tissues and soiled cotton? - Yellow Non-Chlorinated Plastic Bags
• What color biohazard bin is designated for disposing of contaminated recyclable plastics (syringes, tubing, catheters)? - Red Bags
• What puncture-proof container is mandated for disposing of contaminated surgical sharps, needles, and blades? - White Translucent Puncture-Proof Container
• What is the primary physiological mode of transmission for enteric fecal-oral pathogens? - Ingestion of Fecally Contaminated Food, Milk, and Water
• What are inanimate contaminated objects (such as doorknobs, towels, utensils) that transmit pathogens called? - Fomites
• What term describes a nosocomial infection contracted by a patient during the course of receiving hospital healthcare? - Hospital-Acquired Infection (HAI)
• What phenomenon describes bacterial pathogens developing resistance to standard therapeutic antibiotics? - Antimicrobial Resistance (AMR)
• What is the term for a superbug resistant to multiple standard first-line antimicrobial drugs? - Multidrug-Resistant (MDR) Pathogen (e.g., MRSA)
• What is the flagship comprehensive sanitation and open defecation-free mission launched by India on October 2, 2014? - Swachh Bharat Mission
• What national immunization campaign was launched in India in December 2014 to ensure full vaccination coverage for children? - Mission Indradhanush
• What is the flagship public health insurance scheme in India providing ₹5 lakh annual secondary/tertiary coverage per family? - Ayushman Bharat - PMJAY
• What national initiative implemented by the FSSAI aims to transform the country's food system to ensure safe, healthy food? - Eat Right India Movement
• What is the permissible maximum level of trans-fatty acids mandated by FSSAI in all fats and oils in India? - Not more than 2% by weight
• What vector-borne viral disease causing hemorrhagic jaundice is endemic to tropical forests of Africa and South America? - Yellow Fever
• What acute parasitic worm infection is contracted by walking barefoot on soil contaminated with hookworm larvae? - Ancylostomiasis (Hookworm Infection)
• What clinical blood test measures average blood glucose levels over the preceding 2 to 3 months? - Glycated Hemoglobin (HbA1c)
• What HbA1c threshold percentage is diagnostic for clinical Diabetes Mellitus? - 6.5% or higher
• What non-communicable metabolic disorder involves chronic high arterial blood pressure exceeding 140/90 mmHg? - Hypertension
• What form of radiation is non-ionizing and used safely in medical diagnostic ultrasound imaging? - Ultrasonic High-Frequency Sound Waves
• What is the global eradication target year set by the Government of India to eliminate Tuberculosis nationally? - 2025

3. Food Science, Processing and Preservation

• What thermal process destroys vegetative pathogens in milk by heating to 71.7°C for 15 seconds? - High-Temperature Short-Time (HTST) Pasteurization
• What is the traditional batch pasteurization method involving heating milk to 62.8°C for 30 minutes called? - Low-Temperature Long-Time (LTLT) / Holder Pasteurization
• What thermal processing method heats milk to 135–150°C for 2 to 4 seconds to achieve commercial shelf sterility? - Ultra-High Temperature (UHT) Processing
• What enzyme naturally present in raw milk is tested to verify the adequacy of pasteurization? - Alkaline Phosphatase (Phosphatase Test)
• What food preservation technique uses airtight hermetic sealing inside metal cans followed by retorting? - Canning (Appertization)
• Who is celebrated as the 'Father of Canning' for inventing thermal food preservation in 1809? - Nicolas Appert
• What anaerobic, endospore-forming bacterium is the primary target organism for commercial canning sterilization? - Clostridium botulinum
• What lethal neurotoxin produced by Clostridium botulinum in under-processed low-acid canned food causes flaccid paralysis? - Botulinum Toxin (Botulism)
• What high-temperature thermal destruction metric represents the time in minutes required to reduce a microbial population by 90% (1-log)? - D-value (Decimal Reduction Time)
• What thermal metric represents the temperature increase in degrees Celsius required to reduce the D-value by a factor of 10? - Z-value
• What ratio measures the free unbound water available in a food substrate to support microbial proliferation? - Water Activity ($a_w$)
• What is the baseline water activity ($a_w$) of pure distilled liquid water? - 1.0
• Below what critical water activity ($a_w$) threshold is all microbial growth (bacteria, yeasts, and molds) completely inhibited? - 0.60
• What minimum water activity ($a_w$) is required to support the vegetative proliferation of most foodborne bacteria? - 0.90 to 0.91
• What preservation process involves freezing food followed by sublimating frozen ice crystals under high vacuum? - Freeze-Drying (Lyophilization)
• What is the non-enzymatic browning reaction between amino acid amino groups and reducing sugar carbonyl groups? - Maillard Reaction
• What desired aroma and color compounds are synthesized during the Maillard browning of bread crusts and roasted coffee? - Melanoidins
• What potential carcinogen is formed during the high-temperature Maillard frying of starchy foods like potato chips? - Acrylamide
• What non-enzymatic browning reaction occurs when pure sugars are heated above their melting points without proteins? - Caramelization
• What enzyme family catalyzes the rapid oxidative browning of sliced apples, bananas, and potatoes exposed to air? - Polyphenol Oxidase (PPO) / Tyrosinase
• What thermal pre-treatment involves briefly dipping vegetables in boiling water or steam to inactivate native enzymes before freezing? - Blanching
• Which two heat-resistant endogenous plant enzymes are assayed to evaluate the adequacy of industrial blanching? - Peroxidase and Catalase
• What oxidative deterioration of dietary unsaturated fats and oils yields unpleasant off-odors and rancid flavors? - Lipid Auto-oxidation (Oxidative Rancidity)
• What primary unstable chemical intermediates are formed during the initial propagation phase of lipid auto-oxidation? - Hydroperoxides and Free Radicals
• What secondary volatile breakdown aldehyde compound is measured in the Thiobarbituric Acid (TBA) assay for rancidity? - Malondialdehyde (MDA)
• What hydrolytic spoilage occurs when milk fats are broken down by native lipases into free butyric and caproic acids? - Hydrolytic Rancidity
• Name two common synthetic phenolic antioxidants added to edible oils to retard auto-oxidation. - BHA (Butylated Hydroxyanisole) and BHT (Butylated Hydroxytoluene)
• What natural lipid-soluble antioxidant vitamin is widely used to prevent rancidity in packaged snack foods? - Tocopherol (Vitamin E)
• What chemical food preservative is effective in acidic beverages (pH < 4.5) to inhibit yeasts and molds? - Sodium Benzoate
• What chemical preservative is widely used in fruit juices, dried fruits, and wines to inhibit bacterial spoilage and browning? - Potassium Metabisulfite (KMS / Sulfur Dioxide)
• Why is Potassium Metabisulfite unsuitable for preserving naturally red-colored fruit juices (like strawberry or pomegranate)? - Sulfur dioxide bleaches anthocyanin pigments
• What antimicrobial food preservatives are added to cured meats (sausages, bacon) to inhibit Clostridium botulinum? - Sodium Nitrite and Sodium Nitrate
• What carcinogenic compounds can form in the stomach when dietary nitrites react with secondary amines at high cooking heats? - Nitrosamines
• What antimicrobial bacteriocin produced by Lactococcus lactis is an approved natural biopreservative in cheese? - Nisin
• What packaging technology replaces the internal package air atmosphere with a protective gas mix ($\text{N}_2, \text{CO}_2$)? - Modified Atmosphere Packaging (MAP)
• What inert, non-reactive gas is back-flushed into sealed potato chip bags to cushion chips and prevent lipid oxidation? - Nitrogen Gas ($\text{N}_2$)
• What cold non-thermal food preservation method exposes pre-packaged foods to ionizing radiation (gamma rays, electron beams)? - Food Irradiation (Cold Pasteurization)
• What radioactive isotope is the primary source of gamma rays used in industrial food irradiation facilities? - Cobalt-60 ($^{60}\text{Co}$)
• What international radura symbol must be displayed on all commercially irradiated food packages? - Green Radura Logo (Plant within a broken circle)
• What non-thermal technology subjects liquid or packaged foods to hydrostatic pressures up to 600 MPa to inactivate microbes? - High-Pressure Processing (HPP / Pascalization)
• What physical separation process breaks down and reduces the diameter of fat globules in milk to prevent creaming? - Homogenization
• What bacterial starter culture genus converts lactose into lactic acid during commercial yogurt and curd manufacturing? - Lactobacillus (e.g., Lactobacillus bulgaricus) and Streptococcus thermophilus
• What is the primary structural phosphoprotein found in mammalian cow's milk (approx. 80% of total protein)? - Casein
• What milk-clotting aspartic protease enzyme extracted from calf abomasum is used in commercial cheesemaking? - Rennet (Chymosin)
• What is the liquid byproduct remaining after milk has been curdled and strained during cheesemaking? - Whey
• What two functional proteins constitute the viscoelastic gluten matrix in wheat flour dough? - Gliadin and Glutenin
• Which wheat gluten fraction confers cohesiveness and elasticity to kneaded bread dough? - Glutenin
• Which wheat gluten fraction confers dough extensibility and viscous flowing properties? - Gliadin
• What autoimmune gastrointestinal disorder is triggered by the ingestion of gluten proteins in genetically susceptible individuals? - Celiac Disease
• What unicellular budding yeast is used as the leavening agent in commercial baking and ethanol brewing? - Saccharomyces cerevisiae (Baker's / Brewer's Yeast)
• What gas produced by yeast fermentation is trapped in the gluten matrix, causing bread dough to rise? - Carbon Dioxide ($\text{CO}_2$)
• What high-viscosity, water-soluble structural heteropolysaccharide found in citrus peels forms gels in jam making? - Pectin
• What three chemical components are required in proper proportions to form a stable pectin-sugar-acid gel in jams? - High Methoxyl Pectin, Sugar ($\approx 65\%$), and Acid (pH 3.0 to 3.2)
• What optical analytical instrument measures the Total Soluble Solids (°Brix) and sugar concentration of fruit juices? - Refractometer
• What is the minimum Total Soluble Solids (°Brix) standard mandated for commercial fruit jams by FSSAI? - 65° Brix
• What process converts unsaturated liquid vegetable oils into semi-solid fats by adding hydrogen gas under nickel catalysis? - Hydrogenation
• What harmful isomers are generated as an unintended byproduct during the partial industrial hydrogenation of vegetable oils? - Trans-Fatty Acids (Trans Fats)
• Why do dietary trans-fatty acids elevate cardiovascular disease risk? - They increase atherogenic LDL cholesterol while lowering protective HDL cholesterol
• What is the systematic preventive food safety management system based on identifying critical control points? - HACCP (Hazard Analysis and Critical Control Points)
• How many foundational principles constitute the international HACCP food safety framework? - 7 Principles
• What is the statutory regulatory body established in India under the Food Safety and Standards Act, 2006? - FSSAI (Food Safety and Standards Authority of India)
• Where is the national headquarters of the FSSAI located? - New Delhi
• What joint FAO/WHO intergovernmental body develops international harmonized food standards and codes of practice? - Codex Alimentarius Commission (CAC)
• Where is the headquarters of the Codex Alimentarius Commission located? - Rome, Italy
• What voluntary quality certification mark is issued by the Directorate of Marketing and Inspection for agricultural products in India? - AGMARK
• What quality certification standard mark is issued by the Bureau of Indian Standards (BIS) for processed industrial food products? - ISI Mark
• What mandatory logo color represents vegetarian packaged food products in India under FSSAI labeling regulations? - Green Dot within a Green Square Frame
• What mandatory logo color represents non-vegetarian food products containing meat/egg ingredients under FSSAI regulations? - Brown Dot within a Brown Square Frame
• What blue-colored square logo with a dynamic plus sign indicates fortified staple food products under FSSAI norms? - +F (Fortified) Logo
• What green-colored logo with an organic tick certifies genuine organic food products in India? - Jaivik Bharat Logo
• What term describes living microbial dietary supplements that confer gastrointestinal health benefits when ingested in adequate amounts? - Probiotics (e.g., Lactobacillus acidophilus, Bifidobacterium)
• What non-digestible dietary food ingredients selectively stimulate the growth and activity of beneficial colonic bacteria? - Prebiotics (e.g., Inulin, Fructooligosaccharides)
• What synergistic dietary combination of probiotics and prebiotics in a single functional formulation is called? - Synbiotics
• What chemical compound responsible for the pungent heat of chili peppers is measured on the Scoville Heat Scale? - Capsaicin
• What sulfurous compound formed by alliinase enzyme action gives freshly crushed garlic its characteristic odor? - Allicin
• What volatile lachrymatory factor released upon slicing raw onions induces tearing in human eyes? - Syn-Propanethial-S-oxide
• What natural yellow polyphenolic bioactive compound present in turmeric possesses anti-inflammatory properties? - Curcumin
• What polyphenol catechin antioxidant is abundant in unfermented green tea? - Epigallocatechin Gallate (EGCG)
• What red carotenoid antioxidant pigment is concentrated in ripe tomatoes, watermelons, and pink grapefruits? - Lycopene
• What is the commercial flavor-enhancing sodium salt of glutamic acid that imparts the savory 'Umami' taste? - Monosodium Glutamate (MSG / Ajinomoto)
• What artificial intense sweetener is roughly 200 times sweeter than sucrose and degrades at baking temperatures? - Aspartame
• Which genetic metabolic disorder requires strict lifelong avoidance of the artificial sweetener Aspartame? - Phenylketonuria (PKU)
• What artificial sweetener is a chlorinated derivative of sucrose that is heat-stable and roughly 600 times sweeter than sugar? - Sucralose
• What non-nutritive natural high-potency glycoside sweetener is extracted from the leaves of Stevia rebaudiana? - Stevioside / Rebaudioside (Stevia)
• What natural red food colorant is extracted from the dried bodies of female cochineal scale insects? - Carmine (Cochineal Extract / E120)
• What food processing technique exposes liquids to high-frequency ultrasound waves (20–100 kHz) to disrupt microbial cells? - Ultrasonication (Sonication)
• What physical preservation technology utilizes high-voltage electric field pulses across fluid foods to inactivate microbes? - Pulsed Electric Field (PEF) Processing
• What is the temperature danger zone range in food safety where foodborne bacteria multiply most rapidly? - 4°C to 60°C (40°F to 140°F)
• What is the safe recommended internal cooking temperature for poultry and minced meats to destroy Salmonella? - 74°C (165°F)
• What is the minimum recommended holding temperature for hot prepared foods on commercial buffet lines? - 60°C (140°F) or Higher
• What is the maximum recommended refrigeration holding temperature for perishable dairy and meat foods? - 4°C (40°F) or Lower
• What is the standard commercial storage temperature required inside deep-freeze food storage units? - -18°C (0°F) or Lower
• What foodborne intoxication is caused by heat-stable enterotoxins produced by Staphylococcus aureus in room-temperature foods? - Staphylococcal Food Poisoning
• What foodborne pathogen associated with unpasteurized soft cheeses and deli meats can grow at refrigeration temperatures? - Listeria monocytogenes
• What pathogenic strain of Escherichia coli produces Shiga-like toxins causing Hemorrhagic Colitis and Hemolytic Uremic Syndrome? - E. coli O157:H7
• What flagellated foodborne pathogen commonly cross-contaminates raw poultry, unpasteurized milk, and eggs? - Salmonella enterica
• What food spoilage defect occurs when gas-producing anaerobic clostridia cause cans to bulge and swell outward? - Hard Swell / Blown Cans
• What non-gas acid-producing spoilage in canned low-acid foods is caused by Geobacillus stearothermophilus without can swelling? - Flat Sour Spoilage
• What is the rapid non-destructive optical testing method used by egg grading plants to detect internal blood spots and freshness? - Candling
• What is the unit used to determine the internal albumen quality and freshness grade of a hen's egg? - Haugh Unit