Post on 11-Dec-2015
Agenda
Why Fat Replacement? Basic Fats and Oils Technology Functions of Fat in Food Fat Mimetic Technology Reduced Calorie Fats and Fat Substitutes Replacing Trans and Saturated Fat
Over last 25 years, been a dramatic increase in percent of population in North America who are overweight and obese.
Jane Doe is 5’5” and weighed 130 lbs (BMI= 22) in 1980, in 2004 she weighs 160 lbs (BMI=27).
Increase in caloric consumption= 12 calories/day over 25 years
2 Life Savors ¼ cup of skim milk
Decrease in activity level= 10 minutes more commuting/day over 25 years
How much would Jane have to change her eating behaviors to gain this weight?
Overweight and Obesity in America
July is National Hot Dog Month!!! 80 % of the people at a baseball game eat a
Hot Dog. 5 Billion Hot Dogs eaten between Memorial
Day and Labor Day. 50 million Hot Dogs eaten every day in the
US: that’s 80 Hot Dogs/person/year!! 1 Hot Dog has about 150 Calories.
Comparison of Hot Dogs
Beef/Pork Hot Dog:150 Cal; 5 grams Protein; 1 gram CHO; 13 g Fat; 81% Cal from fat
4.8 g Sat Fat; 6.2 g MUFA; 1.2 g PUFA
Turkey Hot Dog:102 Cal; 6 g Protein; 1 g CHO; 8 g Fat(71%)
2.4 g Sat Fat; 2.7 g MUFA; 2.1 g PUFA
Chicken Hot Dog:115 Cal; 6 g PRO; 3 g CHO; 9 g Fat(70%)
2.5g Sat Fat; 3.8 g MUFA; 2.8 g PUFA
Weight Gain
3500 extra Calories = 1 pound of Fat Example: 80 hot dogs per person/year
above required Calories 80 dogs x 150 Calories = 12000 Cal/year 12000/3500 = 3.5 # / year
Why Fat Replacement?
High fat diets are linked to obesity and cardiovascular disease
There is an epidemic of overweight and obesity in the US About 65% are overweight (BMI 25)
(BMI = weight (kg) / Height 2 (m2) About 23% are obese (BMI 30)
RDA for fat is 30% of calories Current consumption is somewhere near 38%
Consumers Are Paying Attention to What They Eat
30% 30% 30%26%
31%23% 20% 19%
13%
29% 26% 26%27% 21%
21%21% 21%
18%
Fat
Satura
ted F
ats
Salt
Cholest
erol
Trans
Fats
Perse
rvat
ives
Sugar
Caffe
ine
Carboh
ydra
tes
Agree Mostly
Completely Agree
“A person should be very cautious serving food with…”
Some Other Consumer Facts
Concern about fat peaked in mid 90’s 51% very cautious in 1994 31% very cautious in 2004
Low carb diets may be the diet du jour but 73% consume reduced fat food 78% are trying to cut down fat in their diet 61% trying to avoid trans fat
And 70% are concerned with calories
Lipids: Definition
A family of compounds soluble in organic compounds but not in water
3 classes of food lipids: Triglycerides: 95 % of lipids in foods Phospholipids: e.g..: lecithin Sterols: e.g..: cholesterol
Triglycerides Are Esters of Glycerol and Fatty Acids
condensation
reaction
Structures linked by ester bonds (R-COOR') and water is released
Glycerol "backbone" is a water-soluble
alcohol
Fatty Acids are chains of carbon atoms with a methyl (-CH3) group at one end and a
carboxylic acid (-COOH) group at the other
Glycerol + 3 Fatty Acids
Triglyceride + 3 water molecules
Some Basic Facts About Fats
Major source plants (soybean, cottonseed, corn, palm)
At room temperature, Oil = liquid, Fat = solid (m.p. varies)
Calorie-dense (9 Kcal/gram) vs. carbs & protein (4 Kcal/g)
Per capita consumption ~80 lb/year (significant inc. since 1980)
38% of dietary calories come from fat (current RDA is 30%)
Saturated and trans-fat consumption increase CHD risk
Unsaturated oils (olive, fish oils) appear to reduce CHD risk
Fatty Acids Vary in Chain Length and Saturation
saturatedstearic acidm.p. 73 oC
“cis”monounsaturated
oleic acidm.p. 5.5 oC
Longer Chain Higher Melting Point
Add Double Bonds Lower Melting Point
Poly-Unsaturation Confers Liquidity (And Reactivity Toward Oxygen)
“cis, cis”linoleic acidm.p. –13 oC
“cis, cis, cis”linolenic acidm.p. –24 oC
More Double Bonds Lower Oxidative and Thermal Stability
Hydrogenation Improves Stability BUT…
“sat”stearic acidm.p. 73 oC
“trans”elaidic acidm.p. 42 oC
“cis”oleic acid
m.p. 5.5 oC
Trans fats behave more like saturated fat
H2
Nutritional Role
Source of essential fatty acids Linoleic and linolenic
Carriers for fat soluble vitamins A, D, E and K
Important source of energy 9 Kcal/g vs. 4 Kcal/g for carbs or protein
Physical and Chemical Functions
Chemical Properties of
Fat or OilLength of carbon chain
Degree of unsaturation
Distribution of fatty acids
Cis-trans configuration
Crystal state of fat
Physical Properties of FoodsRheological properties: viscosity, plasticity, yield stress, thixotropy, gelation, spreadability, lubricity, hardness, stringiness
Thermal properties: melting characteristics, heat transfer coefficient, solid fat index, softening point, polymorphism
Processing behavior: heat stability, viscosity, crystallization, aeration
Post-processing and shelf stability: shear sensitivity, tackiness, migration, dispersion, and stability (physical, chemical, microbiological)
Sensory Functions of Fat in Products
Appearance Gloss, translucency, color, surface uniformity, crystallinity
Texture Viscosity, elasticity, hardness
Flavor Intensity of flavors, flavor and aroma release, flavor profile,
flavor development, time intensity relationships
Mouthfeel Meltability, creaminess, lubricity, thickness, degree of
mouthcoating, mouth warming or cooling
Many Fats and Oils in Food Exist As Emulsions
Discontinuous phaseInternal phaseDispersed phase
Continuous phaseExternal phaseDispersion Medium
Emulsion Types
O/W EMULSION W/O EMULSION
OIL
OIL WATER
WATER
Examples: MayonnaiseMilkSalad DressingCoffee Whiteners
Examples: MargarineTablespreadButter
Historical Context
Consumers became aware of impact of diet on health in 80’s Proposed energy from fat in diet reduced to 30% (from 40-
49%) Began affecting consumer attitudes
Challenge was to produce low-fat products with physical and sensory characteristics as close as possible to full-fat quality “Breakthrough” came with introduction of a microparticulated
protein ingredient called “Simplesse” The search for the next magic bullet ingredient followed
Subsequent development effort revealed consequences of removing fat from a product Alternative ingredients or processes had to be developed as
all the attributes of fat became recognized
Classification
Over 200 commercial fat replacement ingredients Carbohydrate-based
Starch and starch hydrolysis products Fiber based (gums, gels, thickeners, bulking agents)
Protein-based Specially processed proteins Protein/fiber combinations
Lipid-based Synthetic fat substitutes Low-calorie fats Emulsifiers
Approach to Fat Replacement Has Changed
Late 80’s to Mid 90’s
Fat free products with full fat qualityusing magic bullet
technologies
21st CenturyHealthy products with
balanced macronutrients
Fat is a necessary part of diet
Need to cut down bad fats: saturated and trans
Good tasting calorie-reduced light products
Some Basic Terminology Fat Replacer
Blanket term for any ingredient used to replace fat Fat Substitute
Synthetic compound used as direct 1-for-1 replacement Similar chemical structure to fat but resist digestion
Fat Mimetic Non-fat substance requiring high water content Replace some (not all) functions of fat in products
Low-calorie fat Synthetic triglyceride combining unconventional fatty acids resulting in
reduced calorie content Fat Extender
System of ingredients used in combination with standard fats or oils to achieve fat reduction
Fat Replacement Strategies Direct Fat Removal
First strategy to evolve in rush to comply with nutritional recommendations in 80’s
Worked well for milk, some dairy products, some processed meat… but not much else
Formulation Optimization Water replaces fat in higher fat products Optimization with functional ingredients to stabilize product
Processing Technology Vary processing conditions (time, temp, pressure, etc.) to cause
interactions in ingredients or change functionalities Holistic Approach
No single replacer can do it all
Fat Reduction Success Story
Miracle Whip brand salad dressing was one of Kraft's earliest successes at fat reduction, being introduced in the 1930's
Miracle Whip was formulated to provide about half the fat of conventional mayonnaise using a starch gel at about one tenth the level of the fat that it was replacing
Miracle Whip’s success over its 70+ year lifetimeis in part due to the fact that it did not try to duplicate the product that it was replacing, but rather developed its own unique flavor and mouthfeel which is a function of the newmacronutrient composition of the product
Thermal
- Subtle Warmth
Flavor - Release
- Intrinsic Flavors - Time Intensity Profile
Appearance - Whiteness and Opacity
Organoleptic - Lubricity and Mouthcoating
- Yield Stress at Low Shear Rates - Creaminess, Viscosity, Thickness
- Unique Bulk Textures of Cohesiveness, Cut and Peaks
Spoonable Dressings Example
Full Fat Emulsion Products Have Multiple Phases
Dispersed Phase
Continous Phase
Spread
Aqueous Solution of Dairy Proteins, Salt, Gums, etc.
Crystalline and Liquid Oil
Dressing Emulsified Liquid Oil Droplets
Aqueous Solution of Proteins and Carbohydrates
(20%)(80%)
(80%)
(20%)
Something Needs to Replace Fat in Lower Fat Foods
Product Fat Level Formulation Strategy
Milk Yogurt
Pudding Cottage Cheese
5% < 1%
- Adjust Protein, Water, Carbohydrate Ratio - Add Low Levels of
Texture Modifying Ingredients
Spreads Dressings
70-80% < 2%
- Fat Replacement: Substitute or Mimetic
Physical replacement Modify nonfat comp. Control Moisture
Passive
Active
Fat Mimetic Mechanisms for Emulsion Products
There are at least 5 mechanisms by which fat mimetic ingredients act to provide fat texture: Entanglement Network Gels Particle Gels Aggregates Non-interacting Particles
Each provides different rheological properties to a product that the mimic dispersed or continuous phase of an emulsion product such as mayonnaise
Entanglement and Gelation Mimic Continuous Phase
Entanglement Long non-gelling, non-interacting polymers that have large
spheres of hydration Provide slipperiness and viscosity Mimic the continuous phase of mayonnaise Examples are xanthan gum, carrageenan, polydextrose
Network Gels Polymers interact with each other to form more or less
permanent junction zones Provide yield stress and gel structure Mimic the “cut” of a mayonnaise Examples are pectin, alginates, gelatin
Particle Gels Mimic Dispersed Phase
Network forms between polymers but is not continuous throughout the system Simplesse, “breakthrough” fat mimetic, is particle gel made
by microparticulation of whey protein Mimic the dispersed phase of mayonnaise Performance affected by size, shape, surface properties,
and rigidity (or deformability) of the particle Examples: colloidal cellulose and small particle starch Can also be formed by shearing network gels Provide creaminess and body
Interactions Between Particles (or Not)
Particle Gel Aggregates Discrete crystalline or gel particles that reassociate with each
other to form aggregate Similar in functionality and constraints to particle gels If aggregate is continuous, can mimic both dispersed and
continuous phases Examples include starch gel, starch hydrolysates or
microcrystalline cellulose (cellulose gel/cellulose gum) Non-Interacting Particles
Inert particles Provide opacity and reduce cohesiveness Examples include uncooked or retrograded starch, crystalline
cellulose
Microbiological Considerations
Regardless of the mechanism, water is the main ingredient that replaces fat Fat mimetics hold water so that it builds texture like fat
Shelf life and microbiological safety are affected by combination of water activity, acidity, salt, preservatives, heat treatment
Addition of water requires increasing other safety measures Typically acidity of aqueous phase is increased Control of pH is critical Strong acidic notes affect overall sensory quality
Fat Mimetic Systems - KFM
Ingredients: Water, modified food starch, sugar, high fructose corn starch, vinegar, soybean oil*, salt, cellulose gel, natural flavor, artificial flavor, egg yolks*, xanthan gum, mustard flour, lactic acid, cellulose gum, phosphoric acid, vitamin E acetate, lemon juice concentrate, dried garlic, dried onions spice, yellow 6, beta carotene, blue 1, with potassium sorbate and calcium disodium EDTA as preservatives
*Trivial source of fat and cholesterol
The Missing Attributes Needs to address gaps
Flavor partitioning, delivery, character
Reservoir (solvent) for flavor compounds
Mouthfeel factors such as oiliness and mouthcoating
Separate phase from aqueous portion, surface active
Thermal properties of mouthwarming and melt transitions
Liquid at body temperature, Melting transition below body temperature
Current Fat Mimetics Cannot Supply Full Fat Quality
Approach to Fat Mimetics Has Evolved
Because of “missing attributes”, most food manufacturers have taken a step back from fat freeThe learnings from fat free days have allowed
creation of more and better light, low-fat and reduced-fat products
What Is the Logic Behind Fat Substitutes?
Think like a lipase… ...what would make a triglyceride less appealing?
C|C|C
H2-
H2-
- H
-O-C-(CH2)n-CH3
-O-C-(CH2)n-CH3
CH3-(CH2)n-C-O-O
O
O
Change the backbone
Change the fatty acid
Change the linkage
Olestra Is Only FDA-approved Noncaloric Fat Substitute
Chemistry: Different Backbone Sucrose: a disaccharide from glucose and fructose 8 hydroxyl groups for esterification Fatty acid esters at 6 to 8 sites
Typical triglyceride
Sucrose Octaoleate
Olestra Approved for Savory Snacks
Current approval only in prepackaged ready-to-eat savory (i.e. salty or piquant but not sweet) snacks and prepackaged, un-popped popcorn kernels that are ready-to-heat Approved as food additive for savory snacks (chips,
crackers, etc) in 1996 Ruling expanded in 2004 to include popcorn In 2003, FDA removed requirement for advisory label
warning on products made with olestra
Absorption Decreases With More Esters
Backbone Number of Esters
Absorbability
Glycerol 3 100%
Erythritol 4 70%
Xylitol 5 50%
Sucrose 8 0%
Mattson and Volpenhein, J. Nutr. 1972
Does Olestra Function the Same As Triglyceride?
Melting properties vary with fatty acid comp Composition limited to C16-C22, specified degree of
unsaturation Physiological stability (measured by stiffness) requires
incomplete melting
Crystallinity, and polymorphic behavior of crystals, are not the same as TG
Properties of certain fats (e.g. Cocoa butter) rely on specific crystal structures
•Emulsion properties (e.g. Size of droplet) partially dependent on viscosity
Triglycerides Can Be Low Calorie Too!
Commercial options: Salatrim or Caprenin TG containing mixed long chain saturated
fatty acid (LCFA, C18-22) with short or medium chain fatty acids (SCFA, C2-4 or MCFA, C6-10)
Preferred Comp: 1 LCFA: 2 S/MCFA Approximate Caloric Content: 5 cal/g Low Cal due to poor absorption of LCFA
Salatrim/Caprenin Functionality
Melting properties controlled primarily by length of short or medium chain fatty acid
0
10
20
30
40
50
60
70
80
Chain Length
2
3
4
6
8
10
12
14
Melt
i ng P
oin
t (°
C)
Trans Fatty Acids in Shortening
Most difficult challenge has been to replace trans fat in shortening Solid fats are desirable in baked products Saturated fats were replaced by hydrogenated (trans) fats
when health issues surrounding sat fat became known
Science supports the link between trans fatty acids heart disease risk Trans fats elevate LDL cholesterol levels, lower HDL
Major source of dietary trans-fat is partially hydrogenated vegetable oils
Trans Fat Replacement in Reduced Fat Snacks
In the case of baked snacks (crackers and cookies) reformulation to reduce trans fat has been a multi-year research and development effort Liquid vegetable oils would be ideal ingredients because of
their inherently low levels of trans-fat and saturated fat A non-hydrogenated, RBD (refined, bleached and
deodorized) soybean oil was found to perform “adequately” in Nabisco’s SnackWells crackersand cookies owing to their low fat andreduced fat formulas (generally 2-3grams of total fat per serving)
Trans Fat Replacement in Full Fat Snacks
In comparable “full fat” products that contained > 4 fat grams per serving, the food matrix was insufficient to hold the liquid oil in place, Liquid soybean oil “drained” out of such a
product by the action of gravity, and failed to deliver the buttery, signature flavor and light open texture expected by Ritz cracker consumers.
Trans Fat Replacement Solution First practical, low trans-fat solution involved the
use of high melting point mono- and di-glyceride emulsifiers as minor components in liquid oils Used with Triscuit crackers, a product with a high
surface area provided by a woven wheat structure The oil blend containing 4-8% emulsifier
was topically applied to this productimmediately upon its exit from the oven
Worked with Triscuit and Wheat Thins, but not Ritz Needed to change the fat in the dough, as well
as that brushed on top of the cracker
Fat Reduction/Replacement: Summary
Fat mimetics replace the fat in a product, though often sacrificing texture and/or flavor. For this reason, partial fat replacement is generally a more consumer acceptable approach
Trans fatty acids can be replaced , though it is very difficult to remove these fats from baked foods. However, withinvestment of significantresearch efforts, successis possible and in factcan drive sales growth