Module 3 Flashcards
Why use fat and sugar substitutes?
- Excessive caloric consumption along with a sedentary lifestyle are risk factors health problems.
Describe a protein based fat substitute.
- Use protein particles to stabilize and give texture to food - usually digested as a protein.
- Example - Simplesse - based on soy, milk, or egg white protein.
- The protein is partially coagulated by heat, creating a micro dispersion, in a process known as microparticulation.
- Due to the small particle size (0.01 -3 microns) of the protein, we perceive the dispersion as a fluid with a similar creaminess and richess of fat.
- Simplesse is digested as a protein, but due to the micro dispersion formed, only produces ~1-1.3 cal/g
- Applications include: Icecream, yogurt, cheese spreads, salad dresses, soup, coffee creamer, soups, and sauces.
What is microparticulation?
Proteins are coagulated by heat, creating a microdispersion, in a process known as microparticulation. Very small (0.01-3 micron) spheroidal particles are generated.
Describe a carbohydrate based fat replacer.
- They imitate fat’s mouthfeel while contributing to less calories.
- Example: Maltodextrin
- Derived from CHO souces like corn, potato, wheat, and tapioca. It produces a smooth mouthfeel and bland flavour.
- Maltrin is fully digestible, yielding 4 cal/g.
- Other CHO based fat replacers are available that range from non-digestible to partially digestible (0-2 cal/g)
- Applications include: margarine, salad dressings, frozen desserts, frostings, processed meat.
Describe a fat based fat replacer.
- Some are made from long and/or short fatty acid chains. Others have fatty acids linked to sucrose (instead of glycerol - as in normal fat)
- Example - Olestra/Olean
- Made from a sucrose molecule and 6-8 long-chain edible fatty acids forming a sucrose polyester.
- Unlike other fat substitutes, Olestra can withstand high temperatures (e.g., frying), and gives the rich taste and creamy texture of characteristic fat because it is made primarily from fat.
- Enzymes cannot break down Olestra, so it passes through the body unchanged.
- Products containing Olestra must mention that vitamins A, D, E, and K have been added.
- Olestra was approved in the US in 1996, it is not approved for use in Canada.
- Applications include: salty, savory, snacks, and crackers.
How is sweetener defined in Canada?
- Any food additive listed as a sweetener in Table IX.
- E.g., aspartame, sucralose, sorbitol, and maltitol
How does the FDR define sweetening agent?
- Any food for which a standard is provided in Division 18, but does not include those food additives listed in the table in Division 16.
- Examples: Sugar, honey, molasses.
Describe low-calorie sweeteners.
- Aspartame - metabolized as a protein (4 kcal/g); 180-220 x sweeter than sucrose
- Sugar-alcohols - 1.5-3 cal/g; 60% as sweet as glucose
Who should not consume aspartame, and why?
- Individuals with phenylketonuria who cannot metabolize phenylalanine
- Aspartame is composed of phenylalanine and aspartic acid.
Can aspartame be used in baked goods?
No - it degrades at high temperatures.
A best before date is also necessary because it will degrade to DKP over time.
Which sweetener is responsible for the cool-refreshing, menthol-like sensation?
Sugar-alcohols - derived from a wide variety of fruits and berries (or produced commercially by hydrogenating sugars)
They do not promote tooth decay as they are not fermentable by the bacteria in our mouth!
Describe acesulfame-k.
- Non-caloric sweetener
- 200 x sweeter than sucrose
- Not fermented by oral bacteria
- Heat stable
- Stable over wide pH range
- Provides synergistic effect when combined with other sweeteners.
Describe sucralose.
- Non-caloric sweetener
- Chlorinated molecule in which 3 hydroxyl groups of the sucrose molecule are replaced by chlorine
- 600 x sweeter than sucrose
- Heat stable
- Not fermentable by tooth bacteria
Describe steviol glycoside.
- Derived from leaves of the South American Stevia plant
- 100-150 x sweeter than sucrose
- Non caloric sweetener
- Not fermented by tooth bacteria
- Heat and acid stable
What is sensory evaluation?
- A scientific principle used to (1) evoke, (2) measure, (3) analyze, and (4) interpret reactions to those characteristics of foods and materials as they are perceived by the senses of sight, smell, taste, touch, and hearing.
Why is sensory evaluation widely used in the food industry? [6]
- New product development
- Product matching
- Shelf-life studies
- Product reformulation
- Quality control
- Consumer preference
Describe the interrelationships among sensory factors that people use at a grocery store.
Which factors govern the perception of the appearance of food? [6]
- Size
- Shape
- Colour
- Gloss
- Consistency
- Prescence of defects (e.g., mould, bruises)
Describe textural parameters as assessed by the consumer.
- When gently squeezing buns this is a measurement of texture (resistance to bread to deformation under an applied force and also the ability of the bread to regain its shape upon release of the force) - fresher bread = less force; older bread = more force (starch has begun to retrograde.
- Sense toughness of meat when cut with a knife or facial muscles - more force = lower quality meat.
Describe: cutting, compression, tensile strength, and shearing forces.
- Cutting: force goes through food so as to divide it
- Compression: force is squeezed so that food remains in one place
- Tensile strength: force is applied from the material resulting in tearing and pulling apart
- Shearing: force is applied so that one part of the food slides past another
What is flavour?
- Flavour = taste + aroma
- To elicit taste - substance must be water-soluble to be detected by receptors on the tongue
- To elicit aroma - substances must be fat-soluble and volatile for them to interact with the receptors in the nasal passage
When we have a cold, why does food seem so bland?
Inability to detect aroma blunts flavours since you can only detect the taste portion of the equation.
Recall: Flavour = taste + aroma
What are the 3 main types of sensory tests?
- Discriminative and descriptive analyses - both are product-oriented and analytical
- Hedonic/preference/accetability tests - people oriented and ‘affective
Describe discriminative or ‘descriptive’ tests.
- Used to determine whether a difference exists between samples.
- Evaluate new processing treatments
- Panelists likes/dislikes are of no concern
- Backbone of sensory analysis
- Examples: triangle test, pair-difference tests
