Running head: FATS AND OILS

Fats and Oils Lab Report

By June Saxton

8/5//2013

Introduction

In this lab, we will look at different types of fats and oils and evaluate them as to

color, odor and flavor and examine what causes them to become rancid. We will also discuss the

differences between different types of fats and oils and their nutritional value.

Materials and Methods

The ingredients that were used for this sensory lab were safflower oil, olive oil, lard,

butter and crusty French bread. The safflower oil and olive oil were placed in a small glass and

smelled and then swallowed. The lard and butter were spread on a piece crusty French bread and

then tasted and smelled.

Results

Type of Fat Source Color Odor Flavor

Safflower Oil

(Enriched Expeller

Pressed)

Hollywood Brand made

Boulder, Colorado

Light

Yellow

fresh Mild and

harmonious

Olive Oil

(Cold Pressed Extra

Virgin)

Gem Brand made in New York

with olives from Italy, Spain,

Tunisia, Turkey, and Argentina

Apple

Green

fruity Fresh and rotund

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FATS AND OILS

Lard

(Hydrogenated)

Morrell Brand made in Morrell,

Indiana

White Neutral Bland but with

smooth mouth

feel

Butter

(Sweet Cream)

Great Value brand distributed

by Wal-Mart Corporation in

Bentonville, Arkansas

Yellow Sweet and

slightly

salty

Creamy, smooth

sensation on the

pallet

(Conforti, 2008) & (The Olive Oil Source, 2013)

Safflower Oil Olive Oil

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FATS AND OILS

Butter Lard

Discussion

There are two types of rancidity; hydrolytic and oxidative. In hydrolytic rancidity the

chemical bonds are broken down into the properties of water (oxygen and hydrogen) and with

the aid of the enzyme lipase produce free fatty acids and glycerol. These free fatty acids only

produce off flavors and colors in fats with short-chained fatty acids such as butter. Fats with

long-chained fatty acids require the presence of oxygen to produce off colors and flavors. This

the oxidative reaction mentioned earlier. It is more likely to occur in the presence of heat, light or

metals. The more highly unsaturated the fat, the more susceptible it is to oxidative rancidity

(Bennion & Scheule, 2010).

 Highly saturated fats tend to be more stable because in order for a fat to become rancid it

must contain a free fatty acid. Therefore a monounsaturated fat only with only one double bond

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FATS AND OILS

has a better keeping quality than a polyunsaturated fat with two or more double bonds (Bennion

& Scheule, 2010).

Some steps that can be taken to prevent rancidity are: storage at refrigerator temperatures

away from light, moisture and air, use colored containers to keep out the light, vacuum

packaging to keep out the air and adding natural or synthetic anti-oxidants (Bennion & Scheule,

2010).

Antioxidants act as oxygen interceptors in the oxidative process to provide a hydrogen

atom to satisfy the extra free radical causing the chain reaction which produces rancidity to be

broken. Those used commercially are BHA, BHT, TBHQ and propyl gallate.

The natural antioxidants found in common vegetables oils are vitamin C, beta carotene

and Vitamin E. 

A synergist is a substance such as Vitamin C which binds the metals present naturally in

some foods to prevent them from catalyzing the oxidation process. This breaks the chain reaction

that produces rancidity. 

 Lard is the fat from a pig. It may be rendered or unrendered. Unrendered lard is pure

pork fat trimmed off the meat. Rendered lard is pork fat that is melted down, filtered and

clarified and then refrigerated for storage. Rendered lard can also be processed by bleaching,

hydrogenating, emulsified and preservatives added (Cooks, Info., 2011).

 Butter is a pure animal fat made from cream which has been churned to separate the fat

from the liquid (Cooks Info., 2012). Margarine is made from hydrogenated vegetable oils, liquid

vegetable oils, milk, buttermilk or whey plus additives such as Vitamin A and D, artificial colors,

salt and preservatives are also allowed (Bennion & Scheule, 2010).

Cooking oils are refined to process the natural oils from vegetables to remove any

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FATS AND OILS

substances that contribute to off flavor, texture, undesirable color and to standardize them (Vora,

2010). They may also be refined into solid fats by hydrogenation (Bennion & Scheule, 2010).

Extra Virgin Olive Oil is made from fresh good quality olives and processed without

excess heat, additives or solvents. Light olive oil refers to olives oils that are light in taste, aroma

and color. They have the same caloric value as EVOO (The Olive Press, 2013).

Some fats are healthier than others. Olive oil is a mono-saturated fat which has been

shown to have a favorable impact on blood lipids. Soybean oil is an omega-3 polyunsaturated fat

which has been associated with decreased risk of coronary heart disease and hypertension. Butter

is a saturated fat which has been associated with coronary heart disease and high cholesterol.

Therefore, it is appears to be more healthy to consume more mono-unsaturated and poly-

unsaturated fats than saturated fats (Bennion & Scheule, 2010).

 

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FATS AND OILS

References

Bennion, M., & Scheule, B. (2010). Introductory foods. (13th ed.). Upper Saddle River, NJ:

Pearson Prentice Hall.

Conforti, F. D. (2008). Food selection and preparation, a laboratory manual. (2nd ed.).

Blackwell Pub.

Cooks Info. (2011, February 18). Lard. Retrieved from http://www.cooksinfo.com/lard

Cooks Info. (2012, November 13). Butter Retrieved from http://www.cooksinfo.com/butter

The Olive Oil Source. (2013). Olive oil tasting terms. Retrieved from

http://www.oliveoilsource.com/page/olive-oil-tasting-terms

The Olive Press. (2013). About olive oil. Retrieved from

https://www.theolivepress.com/learn/about-olive-oil/

Vora, S. (2010, October 25). The truth: About refined cooking oil. Retrieved from

http://blog.sejalvora.com/2010/10/25/the-truth-about-refined-cooking-oil/

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