Conquering Shelf Life Issues

Blommer Chocolate Company

What is Shelf Life?

Period of time during which a product will retain acceptable:– appearance– aroma– flavor– texture

Key Elements of Shelf Life for the Confectioner

Microbiological SafetyEutetics–Bloom – Fat or sugar

Migration – Moisture or FatLoss of TextureRancidity

What is Chocolate? Chocolate Matrix

Sugar Milk Cocoa

An intimate mixture of solid particles suspended in fat.

Cocoa butter

Unique Properties to Consider

Chocolate contains cocoa butter and sometimes milk, milk fat– Fast flavor release– Melts at Body temperature– Natural Antioxidants

Compound Coatings contain veg fats– Slower Flavor release– Heat resistant, many types– Short Chain Fatty Acids

Categories of Confectionery Shelf Life

Inherent in the Product– CANNOT be prevented

Dependent on Environment– MAY be controlled

Microbiological SafetyAOAC/BAM Methods

Raw nuts may contains pathogens

Milk products may contain Listeria

Raw Material and Finished Product testing– Prevent water contamination

Hold/Release Program critical for product safety

Formulations –#1 Eutetics or Softening

Incompatible fats blended together can decrease shelf lifeCocoa Butter and Palm Kernel Oil are not compatibleGeneral rule of Thumb is to not mix more than 4% PKO with cocoa butter

#2 Graining

If sugars are not dissolved before completion of cooking cycleNeed 25% MoistureHeat to 160-180F while agitatingHave More corn syrup than sucrose solids

#3 Moisture Migration -Loss of Texture

Thin corners could lead to:– Exposed center– Center may dry out– Risk of premature

bloomDry inclusions/change textureMeltaways may need to be tempered

#4 Fat Migration

Equilibrium –Everything goes to a balanced stateCenter fats will rise to surface-soften chocolate and harden centerMilk fat added to prevent FormV to VI

#5 Oxidative Rancidity

High fat centers susceptible to rancidityExposed nuts will bloom firstCauses a stale / cardboard flavor

Manufacturing by Hand or Factory Equipment

Conditions must be maintained to maximize shelf lifeProperly tempered chocolateMold design criticalCooling tunnel parameters critical

Enrobers

Curtain of Chocolate Double enrobe if centers vulnerableIf cooled too Rapidly– Chocolate could crack

If cooled too Slowly– Discolor and soft

May emerge Later in Distribution Process

Liquid Chocolate requires “TEMPERING”

WHY?

Tempering

Improperly tempered chocolate will continue to stabilize– May lead to softening and bloom– May cause Lack of contraction– Dull appearance– Poor snap– Longer setting times

Tempering Sequence50oC

32oC

27oC

30-32oC

time

tem

pera

ture

MeltCool - no crystallizationForm mix of crystalsMelt out unstable polymorphs

Tempering on a Marble Slab

Must temper properly to maximize shelf life

Solid Moulding

Improper designed molds can lead to poor quality –How intricate are they?Warm molds can delay onset of crystallizationCold molds can shock chocolate forming incorrect crystals

Enrobing

High Moisture center-short shelf lifeCenters too warm can detemper chocolateUneven surfaces, center could be exposedViscosity alters coverage rate and could increase feet

Cooling

– Quality depends on how well products are cooled, not just how long

– Properly zoned to Avoid Initial Over Cooling and “Dew Point” effects as Product leaves cooler

– Know tunnel temperatures at specific locations– Long enough to give time for Adequate

Cooling

Cooling

– Chocolate and Compounds require different cooling tunnel parameters

– Chocolate needs to be cooled gently with moderate air

• 55-60F – Compound are best cooled in cooler tunnels

because they spontaneously solidify in a stable crystal form

• 40-45F– All tunnels should increase to room temp at

exit to prevent condensation.

Cooling Tunnel Problems

Inadequate air blowingAir “shadowing” of productOver running tunnelToo cold exit temperature, condensation, sugar bloomLack of temperature probes in tunnelAir conditioning coil drains become clogged (high moistures in tunnel)

Packaging

Packaging types influence stabilityGoal is to keep flavor and texture in and moisture outMoisture can cause cracking of pretzelsConsult supplier

Packaging considerations

Heat sealing-be careful not to cause fat bloom due to excessive heatHigh Moisture pieces loose and trap moisture– Wax paper is semi permeable– an option for high moisture pieces that give off

moisture - fudge

Off odors can occur from inks and type of packaging and also from where packaging is stored

Shelf Life Testing

Robinson Test20 cm X 20 cm Test Material15 g grated chocolate not in contact48 hrs in the Dark20C(68F), 75% RHCompare to ControlApprox equivalent to nine months of shelf life

Storage of Confections

Storage ConditionsTemperature & Humidity

– Maintain correct temperatures to Allow Coating to Stabilize

• Not too cool • May inhibit Chocolate from crystallizing into

Stable Form

– Storage temperatures should be based on expected shelf life

• For longer shelf life, use lower temperature and humidity

Chocolate Storage

Constant temperature is bestRecommend 60-70°F, 50% RH max.

Free of all strong odorsBe particularly aware of “air conditioning” odors

First in — First Out stock rotationTeach personnel how to read code dates

Storage Issues – Points to Consider

If products stored too cold, condensation could form creating sugar bloomIf Freezing candies to halt center oil migration and preserve freshness, care must be taken during rewarmingCompound Coatings more heat resistant due to higher melt points

Moisture Absorption/ Flavor Integrity in Storage

Type of chocolate or compound makes a difference– Dark << Milk << White

Issue of temperature and relative humidityRH less than 50% highly recommendedForm is important -– 10 lb. Bars << wafers or ribbons or chunks

Protect with packaging / air tight containers

Distribution

Shipping Finished Goods

Beware of possible temperature problems– Staging on warm docks (bloom from heat damage)– Movement from cold room to warm humid dock

(condensation and sugar bloom)– Loss of temperature control in shipment

During warm months refrigerated, sealed containers would be requiredCheck temperature and humidity records

Distribution

Light in display cases can influence quality– White chocolate susceptible to light-induced

degradation of flavor due to lack of antioxidants– Exposed nuts would also be susceptible to light-

induced rancidity

Infestation– Examine vehicles, keep temp. controlled– Seal packages to deter insects from penetrating

packaging

Recommended Shelf Life

Category of Product Temperate Conditions Tropical Conditions Milk Chocolate 16 months 12 months Dark Chocolate 24 months 24 months White Chocolate 16 months 12 months Fondant Cream filled chocolates

18 months 12 months

Chocolate with Nuts, etc 12 months 9months Wafer/cereal centered product

12 months 9 months

Longest Life recommendations if properly stored for “Best Before” Date. This can be used as a guide for new product.

Bloom Stability Potential

Hold samples at 30C for approx. 12 hrsHold samples at 20C for approx 12 hrs.Continue this cycling until bloom is observedAssumption– One Week of Cycling=One Month Shelf Life

Moisture Absorption

Bloomed Candies- no barrier coating

Bloomed Candies cut in half

Candy with Barrier Coating Not Bloomed

Candy with Barrier Coating Not Bloomed - Cut in Half

Bloom

Fat Bloom– Fat crystals on the

surface causing gray appearance

Sugar Bloom– Moisture condenses,

dissolves sugar and dries on surface causing a whitish film

Issue

Enrobers trap crumbs, nut pieces, tails from centers– These interact with the chocolate– Lead to softening– Affect flow properties

Remedies

The Solution?– Include screeners in the process– Position them before the chocolate is

subjected to high sheer mixing or pumping stages

• This keeps the crumbs, etc., from being homogenized in the chocolate

Oil Migration Remedies

The only solution is to slow the rate of oil migration– Non-fat ingredients

• Appear to slow migration• Just an illusion

– Critical process considerations– Use well-tempered chocolate coating to

produce the best crystalline matrix in a barrier coating

Barrier Coatings:Chocolate Coatings

Chocolate with a very fine granular structure works well.– Start with well-tempered chocolate– Don’t subject it to too many heating and

cooling cycles prior to application– Cool the finished product under optimum

tunnel conditions.

Barrier Coatings:An Example

Visualize particles in a sand bed– 10 lbs of sand holds 2 lbs of water– If ground into smaller particles, that same 10 lbs of

sand will hold 4 lbs of waterCreated more surface areaSmaller cocoa butter crystals will work the same wayMore oil held to minimize oil migration– Stronger structural integrity=more heat stable

Storage ConditionsOdors

Problem:– Odors are more volatile than flavors– Diffuse through packaging materials

Solution:– Store chocolate products only in a

confectionery warehouse– Avoid storing non-mint and mint flavored

products– Use dry, odor-free pallets

Storage Issues

Summarize

Understand fat system of your product – Cocoa butter and veg fats are not compatible

Milk fat in dark chocolate aids in bloom resistanceCompound coatings are heat resistantMinimize migration by designing resistance into the processTaste everything

Fountain of Youth

We can all try to get there somehow!

Thank you!

QUESTIONS!