ice cream technology developments - oregon...

ICE CREAM TECHNOLOGY ICE CREAM TECHNOLOGY DEVELOPMENTSDEVELOPMENTS

Copyright 2015

Tharp’s Food Technology

All rights reserved

Dr. Bruce W. Tharp Tharp’s Food Technology

175 Strafford Avenue Wayne, PA 19087

[email protected]

web site: www.brucetharp.com

AGENDA

•

High Intensity sweeteners in conventional ice cream

•

Cryogenic hardening•

Alternative gases as overrun

•

Fresh look at low viscosity gums.•

Water control Index

•

Impact of proposed serving size change

•

More information on all in………………………

3

UNCONVENTIONAL SWEETENING SYSTEMS USING HIGH

INTENSITY SWEETENER (HIS)

UNCONVENTIONAL SWEETENER SYSTEMS –

Use of high intensity sweeteners in standardized products.

Involves concept that cost per unit of sweetness (CUS) from HIS may be at least equivalent to or, often, substantially less than that of sucrose with other positive influences.

CUS = cost per lb sweetener/sucrose equivalent sweetness

UNCONVENTIONAL SWEETENER SYSTEMS –

Use of HIS in standardized products.

COST/LBDRY BASIS

SUCROSE EQUIVALENT SWEETNESS.

COST PER UNIT

SWEETNESS (CUS)

Sucrose $0.55 1.00 $0.55HFCS 42 $0.25 1.00 $0.25HIS Blend $18.50 200 $0.0925Notes:Prices, US $, FOB Origin, Summer 2011HIS Blend = 50/25/25 sucralose/aspartame/acesulfame-K

COST PER UNIT SWEETNESS

REF. MOD. A MOD. B% Fat 10.00 10.00 10.00% MSNF 7.50 7.50 7.50% Whey solids 2.50 2.50 2.50% Sucrose 12.00 6.00 9.00% CSS (36 DE) 6.00 6.00 6.00% Maltodextrin (10 DE) 0.00 6.00 3.00% HIS blend* 0.00 0.030 0.015% Stabilizer/emulsifier 0.30 0.30 0.30% Total Solids 38.30 38.330 38.315% Theoretical sweetness ~16 ~16 ~16Water Control Index (WCI) 52 60 55

FREEZING PROFILE DATA

Freezing point (F) (Diff.) 27.23 (Ref.)28.16

(+0.93) 27.70(+0.48)Freezer Index - 22 F (Diff) 49.6 (Ref.) 59.2(+19%) 54.5 (+10%)Texture Stab. Index (Diff.) 0 F to +15 F 12.9 (Ref.) 10.5 (-19%) 11.7 (-10%)*HIS Blend = 50/25/25 sucralose/aspartame/acesulfame-K




(+0.93) 27.70(+0.48)Freezer Index - 22 F )Diff) 49.6 (Ref.) 59.2(+19%) 54.5 (+10%)Texture Stab. Index (Diff.) 0 F to +15 F 12.9 (Ref.) 10.5 (-19%) 11.7 (-10%)*HIS Blend = 50/25/25 sucralose/aspartame/acesulfame-K

Substantial

cost saving

Involved.

•

Stevia update–Cargill "ViaTech"

Individual stevia glycosides isolated, recombined. Said to produce HIS with superior sweetness

perception and flavor properties.Fractions can be combined in a variety of

ways to produce custom blends focused on specific applications.

Improves appeal as a "natural" HIS.

HIGH INTENSITY SWEETENER (HIS) DEVELOPMENT

CRYOGENIC FREEZING UPDATE

•

Mix frozen with liquid nitrogen (LN2)–Virtually no whipping

•

Primary consumer interface limited to retail level

11

CRYOGENIC FREEZING

Sub Zero, Utah

Mix in stainless steel bowl, hand mixed after LN added

12

CRYOGENIC FREEZING

I Cream, Chicago 13

CRYOGENIC FREEZING AT THE PRODUCTION LEVEL

•

The holy grail of cryogenic freezing.•

Theoretically, cryogenic gas, e.g .liquid nitrogen (LN2), could provide both overrun and freezing.–Many patents, no commercial applications to

date .•

Hardening application at wholesale production level limited to high margin products, e.g. novelties.

•

New proprietary technology makes partial cryogenic hardening (PCH) feasible for packaged ice cream

14

15

PARTIAL CRYOGENIC HARDENING

(PCH)FIRST, A REVIEW OF

KEY HARDENING TECHNOLO9GY

•

During hardening, average size of ice crystals and air bubbles increases.

–Mother Nature prefers large particles (low surface area to mass ratio)

•

Most growth at early stages - low degree of freeze concentration

Freeze concentration (stay tuned)Ice crystals are pure frozen water.Freezing concentrates all non-aqueous

components into unfrozen system.»

Increases effect of stabilizer, other water mobility control influences

Increase in viscosity as temperature falls reduces water mobility, rate of air diffusion.

HARDENING REVIEW ICE CRYSTAL/ AIR BUBBLE GROWTH

16

•

Fastest growth rate is at higher temperatures (>~14F - depends on composition)–Less freeze concentration.–Higher degree of water mobility, facilitating

migration of water from small to large crystals. –Lower viscosity, facilitating diffusion of air

from small to large bubbles.•

PCH increases rate of hardening, particularly during high temperature, early stage of hardening.–Decreases time spent at higher temperatures,

reduces growth.

HARDENING REVIEW ICE CRYSTAL/AIR BUBBLE GROWTH

17

•

Effect on growth rate is related to rheology of unfrozen portion–Viscosity etc. increases as temperature falls

Freeze concentrationFrozen water is not a solvent.Freezing concentrates all components

into unfrozen water.Increases influence of stabilizer, other

water mobility control influences»

Increase in viscosity reduces water mobility, rate of air diffusion.

HARDENING REVIEW

19

INFLUENCE OF FREEZE CONCENTRATION ON WATER CONTROL

Stabilizer, other water immobilization influences

20

INFLUENCE OF FREEZE CONCENTRATION ON WATER MOBILITY

FROZEN WATER

Viscosity/water immobilization

As water freezes, water immobilizing agents forced into closer contact, Interaction increases.

21

HARDENING TEMPERATURE EFFECTS

•

As ice cream hardens, viscosity increase via freeze concentration slows growth rate of ice crystals and air bubbles.

•

High temperature - Low freeze concentration, low viscosity, more water mobility – more rapid growth rate.

22

HARDENING TEMPERATURE EFFECTS

•

As ice cream hardens, increase in viscosity slows growth rate of ice crystals and air bubbles.

•

Low temperature - High freeze concentration, high viscosity, less water mobility - slow growth rate

Growth slowest at low temp.

•

As temperature falls, freeze concentration effect changes rheology of unfrozen portion.–Decreasing water mobility slows ice crystal

growth rate– Increasing viscosity reduces ability of air to

migrate and contribute to air bubble growth.

Similar considerations apply whenever ice cream temperature rises during distribution, ergo the desirability of maintaining low storage temperature.

HARDENING TEMPERATURE EFFECTS SUMMARY

23


•

Use LN2 indirectly to accelerate hardening , minimize time in rapid growth temperature range (> 14 F +/-), maximize time in slow growth range. –After freezer exit, portion of ice cream is

cryogenically hardened to very low temperature, added back into ice cream flow.

–Rapidly increases rate of temperature drop in rapid growth zone thus reduces rate of growth of crystals and air bubbles during hardening .

24


25Source: Praxair Inc.


Cryo-freezing tank schematic


"Bits" 0.25" to 1"

Collateral feature – can create new products via introduction of bits with contrasting color and compatible different flavor

•

Composition –5% fat–35% TS–Stabilizer/ emulsifier

- locust bean gum, guar gum, carrageenan, mono-and diglycerides, polysorbate 80

•

Processing– Frozen at 100%, 135% overrun–Hardening – conventional, PCH

•

Accelerated abuse test–Samples cycled -5 F to +5 F, held 12 hours at each

level

PARTIAL CRYOGENIC HARDENING RESULTS OF PLANT TRIALS - LOW FAT ICE CREAM


EFFECT ON PRODUCT TEMPERATURE

PARTIAL CRYOGENIC HARDENING RESULTS OF TRIALS - LOW FAT ICE CREAM


PCH

Rapid Growth Rate(low viscosity)

Conventional hardening0.5 hr.

<5 hr.

>8 hr.

Slow Growth Rate(high viscosity)

~12.5 hrs.. >15 hrs

29

***

EFFECT ON AIR BUBBLES, ICE CRYSTALS

PARTIAL CRYOGENIC HARDENING RESULTS OF TRIALS- LOW FAT ICE CREAM

Source: Praxair Inc.

PCH

PCH

PCH sl. smaller air bubblesPCH sig. smaller ice cryustals

30

EFFECT ON AIR BUBBLES, ICE CRYSTALS (SAME OR).

(



PCH PCH

31

***

EFFECT ON ICE CRYSTALS, AIR BUBBLES



Crystals, bubbles smaller

32

EFFECT ON MELTING PROFILE



PCH melting profile @ 135% OR –

similar to conventional hardening at 100%

33

EFFECT ON PRODUCT CONSISTENCY


Hardness of PCH ice cream at 135% overrun is equivalent to that of control ice cream at 100%.


• Triangle tests

‒ 100% OR mechanical hardening vs. 135% OR mechanical hardening

‒

Difference exists (90%+ confidence)

‒ 100% OR mechanical hardening vs. 135% OR PCH

‒

No difference

‒

PCH ice cream @ 135% OR equivalent to conventionally hardened product at 100% OR

SENSORY EVALUATION



PARTIAL CRYOGENIC HARDENING SUMMARY

•

PCH accelerates hardening in critical higher temperature range–Extends textural shelf life via reduction in

average size of ice crystals (ripening) and air bubbles (disproportionation).

•

Increases uniformity of hardening.•

Reduces hardening time.

•

New product potential via bits with variable colors/flavors. More information at

www.praxairfood.com/icecream

http://www.praxairfood.com/icecream

PARTIAL CRYOGENIC HARDENING Implications re new benchmark for hardening

•

Suggests the existence of a critical hardening temperature (CHT) marking the transition from rapid to slow growth rate.–Would vary depending on freezing profile as

affected by compositional variables.–~15 F in this study, likely varies with freezing profile

as affected by variation in composition – possibly in range of ~12 F to ~16 F.

•

Temperature in CHT range should replace the traditional 0 F as a benchmark for evaluating hardening effectiveness.

37

Disproportionation (similar to ripening of ice crystals) - migration of air from small to large bubbles occurs via diffusion if the viscosity of unfrozen portion is low enough to allow it.

OVERRUN WITH ALTERNATE GAS

Pressure is higher in smaller bubbles than in larger.

At low viscosity (high temp.), air diffuses from small bubbles (pressure greater than in large), migrates and is absorbed into larger ones. (Mother nature prefers large particles.)

Can manage that by increasing viscosity of

unfrozen portion or reducing diffusivity of gas/

•

CO2 interesting vs. carbonation, but not practical for packaged product.

•

Helium - could foster weight loss claims (ahem!)

•

Argon is good choice - lower diffusivity than air–Less migration, less involvement in air bubble

growth.

OVERRUN WITH ALTERNATE GAS


OVERRUN WITH ALTERNATE GAS RESULTS OF TRIALS- LOW FAT ICE CREAM


40

LOW VISCOSITY GUMS – A FRESH LOOK

41

LOW VISCOSITY GUMS IN ICE CREAM

•

Classically, stabilizer functionality involved significant viscosity effects.

•

Trend broken years ago by the introduction of low viscosity guar gum (enzyme hydrolyzed). –Provided useful protection against ice crystal

growth even though low viscosity. –Same phenomenon could apply to acacia (and

other low viscosity ingredients).


•

New kid on the block - gum acacia (a.k.a gum arabic)–Natural gum derived from exudate of acacia

tree. –Excellent emulsification properties ….

widely used for emulsion stability in flavor oil emulsions.Emulsifier functionality different from what's

useful in ice cream.–Very low viscosity, not traditionally used as ice

cream stabilizer.–Recently appeared on label of national brand

43


•

Functionality may be related to freeze concentration effects. – Ice is pure crystalline water, no solutes (e.g.

sugars etc.) or suspended material (e.g. fat, protein)

– In frozen ice cream, all non-aqueous components concentrated in unfrozen phase at levels that increase as freezing progresses. ***

44

LOW VISCOSITY GUMS IN ICE CREAM – Freeze concentration

WATER FROZEN

Water control agents forced into closer contact. Interaction Increases markedly, raising viscosity and dramaticallyincreasing water mobilitycontrol

***

45

Effect of variable guar gum level on the viscosity of the unfrozen phase of ice cream - clear evidence of interaction under influence of freeze concentration .

Bolliger, S., Wildmoser, H., Goff, H. D. and Tharp, B. W. 2000.

Relationships between ice cream mix viscoelasticity and ice crystal growth in ice cream. International Dairy Journal 10. 791 -

797.

Break point

Water removed by freeze concentration (g/100g)

Frozen water

FREEZE CONCENTRATION COMPOSITION (%)

UNFROZEN PORTION IN ICE CREAM

MIX0 %

Frozen

@ 22 F 51%

FROZEN

@ 0 F82%

FROZEN

@-20 F 86.7 %

FROZEN

Fat 10.00 14.62 20.29 21.56MSNF 10.00 14.62 20.29 21.56Sucrose 12.00 17.54 24.34 25.8836 DE CSS 6.00 8.80 12.17 12.94Stabilizer 0.15 0.22 0.30 0.32Total Solids

38.15 55.77 77.39 82.26

STABILIZER IN WATERLevel (%) 0.24 0.49 1.33 1.79Conc'n --- 2.0X 5.5X 7.5X

47

•

Low viscosity in unfrozen mix, freeze concentration can take to useful levels.–Useful in mix processing via easier flow,

improvement in heat exchange properties in plate heat exchangers, etc.

–Positive influence on freezing via reduced viscosities at lower draw temperatures including ultra-low temperature freezing.

–Freeze concentration at low temperature of storage (~7.5 X) could produce iinteraction where useful control over ice crystal growth via water immobilization is possible.

Low temp effects could be irreversible,continue to be functional at higher distribution temperatures.


48

•

Freeze concentration effect could be rationale for unexpected functionality in ice cream–– Not only for low viscosity gums, but other

stabilizer ingredients at obviously low levels based on placement in ingredient list.


LOW VISCOSITY FUNCTIONALITY

•

Makes sense, but waits verification by scientific research.

50

WATER CONTROL INDEX

WATER CONTROL INDEX (WCI) (under development)

•

Characterization of water immobilization in an ice cream composition has historically been a subjective matter.

•

WCI for an ingredient is a rating of the degree to which it restricts water mobility .–For a given mix composition it is the sum of the

water control contribution of individual ingredients.

CONTRIBUTORS TO WATER CONTROL INDEX

•

Fat, mineral components– Little water immobilzation, taken as 0.

•

Carbohydrates (CSS, MDX etc.)•

Water immobilization related to degree of polymerization (DP) – number of monosaccharide units in a molecule.

•

Associated only with large molecules. –DP1 monosaccharide, –DP 2 disaccharide, etc.–DP 4+

NO

NO

YES

WCI for carbohydrate ingredient = % DP 4+

CONTRIBUTORS TO WATER CONTROL INDEX

•

Protein components of MSNF:– Involves molecular weight (MW) and other factors.

Structure, internal chemistry, processing etc. – Pending clarification, focus on MW useful. – WCI for dairy protein 950 - based on average MW.

Protein WCI for a given source of dairy protein – % protein X 950. For example:Conventional MSNF (35% protein x 950) = ~330.Sweet whey solids (12% protein X 950) = ~115.Milk protein isolate (90% protein x 950) = ~855

WCI VALUES FOR VARIOUS ICE CREAM COMPONENTS

Component WCISkim milk solids 330Sweet whey solids 11534 Whey protein concentrate 325Sucrose 0HFCS (any type) 036 DE corn syrup solids 6042 DE CSS 5562 DE CSS 3410 DE Maltodextrin 9540% High maltose CSS 3765% High maltose CSS 16Honey 5

CALCULATION OF COMPOSITION WCI• WCI values for ingredients based on dry solids

– Effectiveness of water-control properties related to concentration in the water of the mix, not in the total mix.

•

Sample calculation: 12% fat, 8% MSNF, 2% whey solids, 12% sucrose, 4% 36 DE CSS (TS 38%, water level 62%)

•

Determine "raw" WCI value by multiplying each ingredient with water immobilization functionality by its WCI:

• MSNF: 0.08 x 330 = 26.4 • Whey solids: 0.02 x 115 = 2.3• CSS 36 DE: 0.04 x 60 = 2.4• Total 31.1

• Mix WCI = "raw" WCI ÷ % of water: 31.1 ÷ 0.68 = 46.•

APPLICATION OF WCIWCI VALUES FOR SEVERAL ICE CREAM COMPOSITIONS

•Guideline: WCI values within ± 5% of each other are considered to be equivalent.

APPLICATION OF WCI

•

Value lies in relative use, i.e., comparison of one product to another. Not intended to be an absolute expression of water mobility.

•

Needs fine tuning.




(+0.93) 27.70(+0.48)Freezer Index - 22 F )Diff) 49.6 (Ref.) 59.2(+19%) 54.5 (+10%)Texture Stab. Index (Diff.) 0 F to +15 F 12.9 (Ref.) 10.5 (-19%) 11.7 (-10%)*HIS Blend = 50/25/25 sucralose/aspartame/acesulfame-K

A WORK IN PROGRESS!

PROPOSED CHANGE TO ICE CREAM SERVING SIZE

•

From ½ cup to 1 cup.–Challenges re nutrient content claims.

Increases the challenge re reducing fat, calories, sugar , etc. in mix composition while maintaining processing parameters and eating quality.

Increased emphasis on achieving higher overrun.Opportunity for new functional

ingredients.Lactylated monglycerides reported to

support good eating quality at high overrun, e.g. 160%

61

MANY THANKS

•

ODI for inviting me –

–and for keeping organized dairy technology alive in

the Pacific Northwest!

•

Lisbeth Goddick, OSU.

•

Reitha McCabe, ODI.

•

To all of you for your attention and courtesy

ice cream technology developments - oregon...

Documents