Fat Substitution in Food: Fat Substitution in Food Miranda Miller Kraft Foods R&D
ACCA Seminar Series October 4, 2005
Agenda: 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
Overweight and Obesity in America: 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!!!: 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: 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: 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?: 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%
Show Obesity Maps: Show Obesity Maps
Consumers Are Paying Attention to What They Eat: Consumers Are Paying Attention to What They Eat “A person should be very cautious serving food with…”
Some Other Consumer Facts: 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
Basic Fats and Oils Technology: Basic Fats and Oils Technology
Lipids: Definition: 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: Triglycerides Are Esters of Glycerol and Fatty Acids condensation
reaction Structures linked by ester bonds (R-COOR') and water is released Glycerol + 3 Fatty Acids Triglyceride + 3 water molecules
Some Basic Facts About Fats: 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: Fatty Acids Vary in Chain Length and Saturation saturated
stearic acid
m.p. 73 oC “cis”
monounsaturated
oleic acid
m.p. 5.5 oC Longer Chain Higher Melting Point Add Double Bonds Lower Melting Point
Poly-Unsaturation Confers Liquidity (And Reactivity Toward Oxygen): Poly-Unsaturation Confers Liquidity (And Reactivity Toward Oxygen) More Double Bonds Lower Oxidative and Thermal Stability
Hydrogenation Improves Stability BUT…: Hydrogenation Improves Stability BUT… Trans fats behave more like saturated fat H2
Functions of Fat in Food: Functions of Fat in Food
Nutritional Role: 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: Physical and Chemical Functions Chemical Properties of Fat or Oil
Length of carbon chain
Degree of unsaturation
Distribution of fatty acids
Cis-trans configuration
Crystal state of fat Physical Properties of Foods
Rheological 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: 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: Many Fats and Oils in Food Exist As Emulsions Discontinuous phase
Internal phase
Dispersed phase Continuous phase
External phase
Dispersion Medium
Emulsion Types: Emulsion Types O/W EMULSION W/O EMULSION OIL OIL WATER WATER Examples: Mayonnaise
Milk
Salad Dressing
Coffee Whiteners Examples: Margarine
Tablespread
Butter
Microstructure of Mayonnaise: Microstructure of Mayonnaise
Fat Replacers: Fat Replacers
Historical Context: 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: 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: Approach to Fat Replacement Has Changed Late 80’s to Mid 90’s
Fat free products with full fat quality using magic bullet technologies 21st Century
Healthy 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: 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: 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 Mimetic Technology: Fat Mimetic Technology
Fat Reduction Success Story: 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 lifetime is 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 new macronutrient composition of the product
Spoonable Dressings Example: Spoonable Dressings Example
Full Fat Emulsion Products Have Multiple Phases: Full Fat Emulsion Products Have Multiple Phases (20%) (80%) (80%) (20%)
Something Needs to Replace Fat in Lower Fat Foods: Something Needs to Replace Fat in Lower Fat Foods Passive Active
Fat Mimetic Mechanisms for Emulsion Products: 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 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: 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): 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: 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: 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
Current Fat Mimetics Cannot Supply Full Fat Quality: Current Fat Mimetics Cannot Supply Full Fat Quality
Approach to Fat Mimetics Has Evolved: Approach to Fat Mimetics Has Evolved
Because of “missing attributes”, most food manufacturers have taken a step back from fat free
The learnings from fat free days have allowed creation of more and better light, low-fat and reduced-fat products
Reduced Calorie Fat Substitutes: Reduced Calorie Fat Substitutes
What Is the Logic Behind Fat Substitutes?: What Is the Logic Behind Fat Substitutes? Think like a lipase…
...what would make a triglyceride less appealing?
Olestra Is Only FDA-approved Noncaloric Fat Substitute: 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: 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 : Absorption Decreases With More Esters Mattson and Volpenhein, J. Nutr. 1972
Does Olestra Function the Same As Triglyceride? : 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!: 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: Salatrim/Caprenin Functionality Melting properties controlled primarily by length of short or medium chain fatty acid Melting Point (°C)
Replacing Trans and Saturated Fat: Replacing Trans and Saturated Fat
Trans Fatty Acids in Shortening: 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 : 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 crackers and cookies owing to their low fat and reduced fat formulas (generally 2-3 grams of total fat per serving)
Trans Fat Replacement in Full Fat Snacks: 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: 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 product immediately 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 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, with investment of significant research efforts, success is possible and in fact can drive sales growth