Fats and Oils

Which term refers to a diverse group of water-insoluble organic compounds, including fats, oils, phospholipids, and sterols, that are generally soluble in organic solvents?

Lipids

Which lipid is generally solid at room temperature and is composed mainly of triglycerides?

Fat

Which lipid is generally liquid at room temperature and is composed mainly of triglycerides?

Oil

In a triglyceride molecule, which component forms the three-carbon backbone to which fatty acids are attached?

Glycerol

In a triglyceride molecule, what forms the side chains attached to the glycerol backbone?

Fatty acids

Animal fats are predominantly composed of which type of fatty acid?

Saturated fatty acids

Plant fats are predominantly composed of which type of fatty acid?

Unsaturated fatty acids

Which type of fatty acid contains no carbon-carbon double bonds and is therefore fully saturated with hydrogen?

Saturated fatty acid

Which type of fatty acid contains one or more carbon-carbon double bonds in its hydrocarbon chain?

Unsaturated fatty acid

Which type of unsaturated fatty acid contains only one carbon-carbon double bond?

Monounsaturated fatty acid

Which type of unsaturated fatty acid contains two or more carbon-carbon double bonds?

Polyunsaturated fatty acid

Which polyunsaturated fatty acid family has its first double bond at the third carbon from the methyl (omega) end?

Omega-3

Which polyunsaturated fatty acid family has its first double bond at the sixth carbon from the methyl (omega) end?

Omega-6

Which is the essential omega-3 fatty acid?

Alpha-linolenic acid

Which is the essential omega-6 fatty acid?

Linoleic acid

Which omega-3 fatty acid competes with arachidonic acid for cyclooxygenase and lipoxygenase enzymes, thereby influencing eicosanoid production?

Eicosapentaenoic acid (EPA)

Which long-chain omega-3 polyunsaturated fatty acid, commonly found in fatty fish and fish oils, competes with arachidonic acid in eicosanoid synthesis?

Eicosapentaenoic acid (EPA)

Which long-chain omega-3 polyunsaturated fatty acid is especially important for brain and retinal development and function?

Docosahexaenoic acid (DHA)

Which foods are considered good sources of omega-3 fatty acids?

Fatty fish, flaxseed, chia seeds, and walnuts

Which foods are considered major sources of omega-6 fatty acids?

Corn, soybean, sunflower, and safflower oils

Which type of fat can be easily seen and separated from food, such as butter, margarine, cooking oil, and on meat?

Visible fat

Which type of fat is naturally incorporated within foods and is not easily seen or separated, such as the fat in milk, eggs, nuts, meat, and baked products?

Invisible fat

How much energy does 1 gram of fat provide?

9 kcal/g

Which compounds are formed when glycerol is esterified with only one or two fatty acids?

Mono- and diglycerides

Which class of lipids contains glycerol, fatty acids, phosphate, and a nitrogen-containing group and is an important component of cell membranes?

Phospholipids

Which phospholipid is commonly used as a natural emulsifying agent in foods and is abundant in egg yolk and soybeans?

Lecithin

Which term refers to the percentage of solid fat present in a fat or oil at a specified temperature, and is used to assess its consistency and plasticity?

Solid Fat Index

A fat sample with a higher proportion of solid fat at a given temperature will have which characteristic?

Higher solid fat index

Which term describes the ability of a fat to exist in more than one crystalline form, each having different melting points and physical properties?

Polymorphism

Which property of fat refers to its ability to be molded, spread, or shaped under pressure without breaking, especially over a range of temperatures?

Plasticity

Which property of fat refers to the temperature at which a solid fat changes into a liquid?

Melting point

Which property refers to the temperature at which a liquid fat begins to crystallize and become solid?

Solidification temperature

Fats and oils are generally insoluble in water but soluble in organic solvents. This characteristic refers to their:

Solubility

Which property measures the degree to which light is bent or refracted as it passes through a fat or oil and may be used in assessing its identity and purity?

Refractive index

The ability of certain lipid compounds to lower interfacial tension and help oil and water remain dispersed together describes their:

Surfactant properties

Which property describes the ability of a fat or oil to withstand heating without undergoing excessive chemical decomposition or deterioration?

Thermal stability

The temperature at which a heated fat or oil begins to produce a continuous visible smoke due to decomposition is called its:

Smoke point

Which term refers to the temperature at which vapors from a heated fat or oil can ignite momentarily when exposed to a flame?

Flash point

A cook heats oil until its vapors ignite briefly when exposed to a flame but do not continue burning. This best exemplifies the:

Flash point

A cook heats oil until it begins to give off a continuous visible bluish smoke, indicating that the fat is starting to decompose. This best exemplifies the:

Smoke point

Which term refers to the temperature at which vapors from a heated fat or oil ignite and continue to burn for at least several seconds?

Fire point

Which statement best distinguishes the flash point from the fire point of a fat or oil?

Flash point is when vapors ignite briefly, while fire point is when they ignite and continue burning

Which change occurs as frying fat undergoes progressive degradation during repeated heating?

Smoke point decreases

Repeatedly reused frying oil that has deteriorated is most likely to:

Become more viscous and foam more readily

Which combination best describes the effects of fat degradation?

Lower smoke point, higher viscosity, increased foaming

Which type of fat deterioration occurs when high heat causes thermal breakdown/decomposition of triglycerides and fatty acids?

Pyrolysis

Which type of fat deterioration occurs when oxygen reacts with unsaturated fatty acids, producing off-flavors and rancidity?

Oxidation

Which type of fat deterioration occurs when water splits triglycerides into glycerol and free fatty acids?

Hydrolysis

During repeated frying, oil may deteriorate because it reacts with crumbs, proteins, sugars, and other residues released from food. This is best described as:

Reaction with food residue

Which reaction involves the hydrolysis of triglycerides with a strong alkali such as sodium hydroxide or potassium hydroxide, producing glycerol and soap?

Saponification

When lihiya (lye) is added to miki noodles, the strong alkali can react with fats present in the mixture, producing soap-like salts and glycerol. This phenomenon is called:

Saponification

Which term refers to the development of unpleasant odors and flavors in fats and oils due to deterioration?

Rancidity

Which type of rancidity occurs when water or lipase enzymes hydrolyze triglycerides, releasing free fatty acids that produce unpleasant odors and flavors?

Hydrolytic rancidity

Which type of rancidity occurs when oxygen reacts with unsaturated fatty acids, forming peroxides and other compounds responsible for undesirable odors and flavors?

Oxidative rancidity

Which rancidity is more common in saturated fats?

Hydrolytic rancidity

Which rancidity is more common in unsaturated fats?

Oxidative rancidity

Which value is commonly used to measure the extent of primary oxidation in fats and oils by determining the amount of peroxides formed?

Peroxide value

Which value is used to measure the degree of unsaturation in fats and oils by determining the amount of iodine absorbed by their double bonds?

Iodine value

A higher iodine value generally indicates that a fat or oil contains:

More unsaturated fatty acids

Which substance helps delay oxidation and rancidity in fats and oils by inhibiting free-radical reactions?

Antioxidant

Which is a natural antioxidant commonly present in fats and oils?

Tocopherol

Which group consists of synthetic antioxidants commonly added to fats and oils to delay oxidative rancidity?

BHA, BHT, TBHQ, and propyl gallate

Which statement best describes the effect of antioxidants on fats and oils?

They delay the development of oxidative rancidity

Which pungent, irritating aldehyde is formed when glycerol is dehydrated during overheating of fats and oils, contributing to the irritating smoke produced?

Acrolein

Which process involves the addition of hydrogen to carbon-carbon double bonds in unsaturated fatty acids, making the fat more saturated and generally more solid?

Hydrogenation

Partial hydrogenation of vegetable oils may result in the formation of:

Trans fatty acids

Which type of oil is commonly subjected to hydrogenation to make it more saturated and solid at room temperature?

Unsaturated vegetable oil

Which metal is commonly used as a catalyst in the hydrogenation of unsaturated vegetable oils?

Nickel

Which fat is obtained from milk or cream and is classified as an animal fat?

Butter

Which animal fat is obtained primarily from pig adipose tissue?

Lard

Which animal fat is obtained mainly from the fatty tissues of cattle or sheep?

Tallow

Which animal-derived oil is particularly known as a source of long-chain omega-3 fatty acids such as EPA and DHA?

Fish oil

Which broad category includes oils extracted from plant sources such as seeds, fruits, and kernels?

Vegetable oils

Which plant oil is obtained primarily from the fruit of the olive tree?

Olive oil

Which oil is commonly subjected to winterization, a process that removes higher-melting components so the oil remains clear at low temperatures?

Cottonseed oil

Which plant oil is extracted from soybeans?

Soybean oil

Which plant oil is obtained mainly from the germ of corn kernels?

Corn oil

Which vegetable oil is derived from rapeseed varieties bred to contain low levels of erucic acid?

Canola oil

Which fat product is made from vegetable oils and is formulated to be solid or semi-solid at room temperature, commonly for baking and frying?

Vegetable shortening

Which fat product is a water-in-oil emulsion commonly made from vegetable oils and used as a butter substitute?

Margarine

Which plant oil is extracted from the meat or kernel of mature coconuts and is naturally rich in saturated fatty acids?

Coconut oil

Which type of coconut oil is produced from fresh coconut without extensive refining, bleaching, or deodorizing?

Virgin coconut oil

Which oil is obtained from the fleshy mesocarp of the oil palm fruit?

Palm oil

Which oil is obtained specifically from the kernel or seed of the oil palm fruit?

Palm kernel oil

Which statement correctly distinguishes palm oil from palm kernel oil?

Palm oil comes from the mesocarp, while palm kernel oil comes from the seed

Which animal fat is traditionally used in products such as hopia and Argao torta to contribute richness, tenderness, and characteristic flavor?

Lard

Which process involves cooling an oil to crystallize and remove higher-melting triglycerides or waxes, allowing the remaining oil to stay clear at refrigeration temperatures?

Winterization

Which animal fat product is obtained from beef fat or suet, with much of the solid stearin removed, leaving a softer oil used historically in margarine manufacture?

Oleo oil

Which term refers to the hard fat located around the kidneys and loins of cattle or sheep?

Suet

As the degree of saturation of a fat increases, its melting point generally:

Increases

As the degree of saturation increases, a fat is more likely to be:

Solid at room temperature

As the degree of unsaturation increases, the melting point of a fat generally:

Decreases

As the degree of unsaturation increases, a fat or oil becomes more susceptible to:

Oxidation

A fat with a higher degree of unsaturation generally has a:

Higher iodine value

A fat with a higher degree of saturation generally has a:

Lower iodine value

Which type of fat or oil is generally most desirable for frying?

Fat with a high smoke point

Which cooking methods generally use only a small amount of fat to cook food quickly over relatively high heat?

Stir-frying and sautéing

Which function of shortening produces tenderness in flour mixtures by coating or “waterproofing” flour particles, thereby limiting gluten development?

Shortening

Which salad dressing is classified as a temporary emulsion because the oil and vinegar separate on standing?

French dressing

Which salad dressing is considered a permanent emulsion stabilized primarily by egg yolk emulsifiers such as lecithin?

Mayonnaise