Quality optimization through the use of minimal i processing and MAP Technologies. Professor Department t of Food Science McGill University

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1 Quality optimization through the use of minimal i processing and MAP Technologies Hosahalli S. Ramaswamy Professor Department t of Food Science McGill University CMC Symposium Toronto, September 18, 2008

2 Meat Nutritionally very rich Typically y a low acid food Supports the activity of spoilage and pathogenic micro-organisms and enzymes Very short shelf life Need well controlled refrigerated system for marketing Need other preservation techniques

3 Conventional Preservation Methods Thermal processing Cooking, Pasteurization, Sterilization, Refrigeration and Freezing Drying Curing, Smoking etc. Irradiation Minimal and Alternate Processing Methods

4 Minimal/Alternate Processing Selected Minimal/Alternate Processing HP Pressure Processing Pasteurization, Sterilization, Kinetics Pressure shift freezing/thawing Pulsed Electric Fields Ohmic Heating Pulsed Light MAP (Sous-vide) discussed by others

5 High Pressure Processing HP processing is an emerging g and Novel technology Derived from material science areas Hite (1899) - milk Gaining tremendous popularity in recent years

6 Two elephants balancing on a dime can create a Pressure of 400 MPa = psi

7 HP Processing Principles Iso-static principle: Application of pressure is instantaneous t and uniform through out the sample Le Chateliers s Principle Reactions resulting in a volume change are influenced by high pressure applications Reactions with a volume decrease are accelerated Reactions with a volume increase are suppressed

8 Kinetic Energy and Molecular ordering Molecular Ordering At constant T, an increase in pressure, increases the degree of ordering of the molecules Like temperature, the pressure increases the kinetic energy associated with the molecules Combination of pressure and temperature will synergistically accelerate the kinetics

9 HP Effects HP can result in cell wall / tissue rupture HP exerts extensive mechanical stress HP does not affect covalent bonds Other bonds are affected resulting in changes in functional properties

10 High Pressure Processing HP mostly affects bio-molecules - destroys microorganisms, especially vegetative cells. Microbial spores are more resistant. - inactivates enzymes - alters functional properties However, HP treatment generally results almost in no changes in nutritional quality Red color and texture are affected

11 HP Application Areas Pasteurization: Sterilization: Juices, milk & meat and fish High and low acid foods Texture modification: Fish, egg, proteins, starches Functional changes: Cheese, yogurt, surimi Specialty processes: Freezing, thawing, fat crystallization, enhancing reaction kinetics

12 Major advantages of HP processing Relatively low temperature operation Instantaneous t response and short ttime treatmentt t Uniform pressure, independent of size and shape Natural quality (flavor, color nutrients, t etc) Waste free operation and energy saving possibilities Minimal destructive effects on nutrients

13 Commercial meat products Meat (400 MPa, Spain) for shelf life, tender & color Sliced ham Marinated kipper (185MPa, -17 C, Japan, 2000) for shelf life & texture Avomax (USA) Oyster (USA, 1998) for shelf life & quality

14 Equipment HP Dynamics Inc Avure STANSTED NC Hyperbaric ACB

15 State of the Art High Pressure Pilot Plant at McGill

16 High Pressure Processing Equipment (ACB at McGill) 900MPa; 80 o C; 8.5 cm diameter; 30 cm height

17 Process Development Research Requires data on. HP inactivation kinetics of Enzymes HP destruction kinetics of spoilage bacteria HP destruction kinetics of pathogenic bacteria HP effects on quality changes HP Process establishment, verification storage, and challenge studies

18 Pasteurization Well studied Guidelines have been developed (USDA - FDA) Processes now must demonstrate 5 log reduction in pressure resistant t pathogens Examples: Listeria monocytogenes, E. coli 0157:H7, Salmonella sp. 1 min at MPa adequate for juices 1 min at MPa adequate for juices Results in safe - shelf stable high quality product

19 Extended d Shelf-Life (ESL) Minimum Requirement: 5D of most resistant pathogen (Pasteurization) Requires Kinetic Data

20 7 HP destruction kinetics of Listeria monocytogenes in pork Log survivo ors (CFU U/g) MPa 350 MPa 400 MPa 350 MPa 300 MPa Time (min) Mussa et al., 1998

21 HP effects on Pork: Quality Microbiological shelf-life (days) of HP treated Pork 0C 5C 10C Untreated HP Treated

22 HP effects on salami: safety and quality No pressure effects on color No pressure effects on sensory quality HP treatment reduced Escherichia coli, O157:H7 counts by >4 log cycles Hungarian salami (ph 4.8, aw 0.93 stayed stable during storage up to 4 weeks at 15C Gill and Ramaswamy (2008) : HC Collaboration

23 Refrigerated Meat: spoilage 4 spoilage bacterial strains Brochothryx thermosphacta Lactobacillus sp. Carnobacterium divergens and Serratia liquefaciens All strains isolated from refrigerated meat Piette and Ramaswamy: CFRA Collaboration

24 Pressure effects on B. thermosphacta Effect of HP on destrution of Brochothrix thermosphacta Log (mpngu/cm2) MPa D300 = 6.8 min D400 = 2.7 min D500 = 1.6 min D600 = 1.1 min y = x y = x y = x y = x MPa MPa 500 MPa Treatment time (min) 300MPa 400MPa 500MPa 600MPa Piette and Ramaswamy: CFRA Collaboration

25 Pressure effects on Lactobacillus sp Effect of HP on destruction of Lactobacillus sp Log (mpn ngu/cm2) D300 = 40 min D400 = 15 min D500 = 6.5 min D600 = 5.4 min y = x y = x y = x y = x Treatmemt Time (min) Linear (300) Piette and Ramaswamy: CFRA Collaboration

26 Pressure Resistance of strains: Brochothrix thermosphacta, h t Serratia liquefaciens, i Carnobacterium divergens, Lactobacillus sp Log (D Val lue, min) Bt Sl Lac Cd y = x y = x 0045x y Lact = x z = MPa Bt y = & x Sl z = MPa Cd z = 222 MPa Pressure (MPa)

27 More Complex Sterilization Considered as a Novel Process; Hence safety of process must be demonstrated Conventional kinetics may not apply Hence, new data needed to for safety demonstration

28 HP Sterilization Yields a shelf-stable product Spores of both spoilage and public health concern need to be destroyed Spore destruction requires high pressure and high temperature combination High pressure can accelerate the destruction Therefore permits the use of milder processing Therefore, permits the use of milder processing conditions: Quality advantage

29 HP sterilization: Principle Pack and Load sample Compression Bring initial and quickly heating temperature pressurize increases to 90C chamber to sample 700 MPa temperature to 125C Delivery of target lethality - Safe Depressurize. Hold until product Rapid heating & cooling - High quality product Sample cools to 90C instantaneously t sterility is achieved: 1-5min

30 Spore destruction kinetics: C. sporogenes in ground beef 8 Log sur rvivors (C CFU/g) MPa, 80 C 900MPa, 90 C 900MPa, 100 C Time (min) Zhu, Naim, Shao, Marcotte, Ramaswamy, A CRDA Collaboration

31 Pressure Resistance of Clostridium botulinum spores (Health Canada Collaboration; Dr. Austin) ) 8 Survival count Log( (N/No* MPa 100C 3min 900MPa 100C 0.5min 900MPa 90C 12min 900Ma 90C 4min 800MPa 90C 15min 800MPa 90C 5min IB1-B CK2-A MRB Langeland A6 GA0108BEC PA9508B 13983B H461297F GA0101AJO HO9504A High pressure treatment Higher the survivor count, higher the resistance

32 More severe pressure conditions /No*10 7 ) Survival co ount Log(N MPa 100C 3min 900MPa 90C 12min 800MPa 90C 15min High pressure treatment t t IB1-B CK2-A MRB Langeland A6 GA0108BEC PA9508B 13983B H461297F GA0101AJO HO9504A

33 Survivor curves for PA9508B Most resistant strain C. Botulinum PA 9508B ZT at 900MPa /ml) Survival count Log(CFU/ Log(D value) Temperature(C) C. Botulinum PA9508B Zp at 90C 0 ) Time (min) 900MPa 100C 900MPa 90C 800MPa 90C Log( D value More sensitive to temperature than pressure Pressure (MPa)

34 HP destruction kinetics of C. botulinum (900 MPa, C) 8 7 No*10 7 ) log(n/ C 90C C Time (min) Shao, Ramaswamy, Austin, 2008 HC Colloaboration

35 Kinetic Parameters of C. botulinum PA9508B Spores D Values Z P Values Pressur e Tempe rature Uncorrected Corrected Pressure Uncorrected Corrected (MPa) Zp value( C ) R 2 Zp value( C ) R 2 (MPa) ( C ) D value (min) R 2 D value (min) R Pressure (MPa) Calculated D values(min) at temperature ( C) * * * Real experimental values Shao, Ramaswamy, Austin, HC Colloaboration *

36 Effect on HP treatment on quality Salami, before and after Salmon, before and after

37 Effect on HP treatment on quality Milk and strawberry, before and after

38 Effect on HP treatment on quality Cheese and Milk, before and after

39 Effect on HP treatment on quality Chicken, beef and pork before and after

40 Pressure Shift Freezing Phase diagram of water under high pressure Water-ice I: transition point decreases from 0 C to -21 C at 210 MPa Super-cooling allows a rapid and uniform ice- nucleation rate for freezing Alowphase-change point A low phase change point offers a large ΔT for thawing

41 Pressure Shift Freezing Process Advantages Fine ice crystals No need for ultra rapid freezing Structure protection Texture firming

42 Fresh tissue Air Frozen Immersion Frozen Ice Crystals in Salmon Frozen by Different Techniques Zhu et al PSF 100 MPa PSF 150 MPa PSF 200 MPa

43 Size of ice crystals in salmon frozen by different techniques Zhu et al Parameter Cross section area Unfrozen Air Frozen Liquid Immersion Freezing PSF 100 MPa 260 PSF 150 MPa 63 PSF 200 MPa 23

44 HP Thawing Zhu et al Advantages Rapid Thawing (1/3rd time) Less Drip Microbial control Texture firming

45 Thawing time of Atlantic salmon samples (mean±s.d., n=3) Zhu et al Thawing treatment 0.1 MPa (4 C) 0.1 MPa (20 C) 100 MPa (20 C) 150 MPa (20 C) 200 MPa (20 C) Thawing time (min) 94.3±3.4 a 26.6±2.1 b 22.6±1.4 c 22.6±1.4 4c 17.0±1.3 d Different letters (a, b, c, d) indicate significant difference (P < 0.05)

46 Zhu et al Texture of HP thawed salmon 200MPa made sample more firmer 15 Peak penetrat tion force (N) Unfrozen control Air freezing Plate freezing L N 2 freezing 0.1MPa (4 o C) 0.1MPa (20 o C) 100MPa (20 o C) 150MPa (20 o C) 200MPa (20 o C)

47 Ohmic heating? Electrode Principle R V Heat generation occurs when an electric current is passed through an electrically conducting food product. Other names Electrode Food Product An electrical circuit analogue Direct resistance heating Joule effect heating Electroconductive heating Electroresistive heating

48 Advantages of Ohmic Heating Very rapid heating No need for hot heat transfer surface Gentle handling of particulates No moving parts Quiet operation Easy process control Better energy conservation than MW Easier tailoring of particle/liquid heating

49 Time-Temperature Profiles Ohmic vs Conventional 80 Water 95v 68v Bath 70 Temper rature ( o C) v Time (min)

50 Frankfurter/Sausage Preparation/Heating Chiu and Ramaswamy Water Bath Ohmic Heating

51 Ham Study Ohmic vs. Conventional Ohmic cooked product ~ Lighter color Softer & chewier texture Lower water holding capacity Lower cooking loss Lower water activity (longer shelf life) Lower cooking time (90% reduction)

52 Pulsed Light An innovative technological concept Has potential for shelf-life extension Potentially a non-thermal technique Effective for surface decontamination of microorganisms i Our studies show promise for PL treatment for cold smoked vacuum packaged salmon to control Listeria monocytogenes and C. botulinum A and E.

53 Pulsed Light Involves intense and short duration pulses of broad-spectrum white light, Each pulse lasts a fraction of a second, but the pulse intensity is 20,000 X intensity of sunlight Pulsed light treatment is effective when light can penetrate the package and product surfaces Process mostly limited i to surface decontamination of foods Useful to control post process contamination

54 Pulsed Light Equipment Trigger cable Flash lamp L Petri dish Treatment chamber Discharge cable Pulse generator

55 Pulsed Light destruction kinetics Residual concentra ation of C. botulinum (6 62A) y = x R 2 = D (800V) = 4.09 s y = x R 2 = D (700V) = s y = x R 2 = D (600V) = s 800V 700V 600V Russ) Residual concentratio on of C. botulinum (E y = x R 2 = D (800V) = s y = x R 2 = D (700V) = s y = x R 2 = D (600V) = s 800 V 700 V 600 V Treatment time (sec) Treatment time (sec) Figure 1. Survival curves of C. botulinum 62 A on TPGY Figure 2 Survival curves of C. botulinum E Russ on TPGY

56 Pulsed Electric Field (PEF) Computer Product Flow Product Pipes Electrical Connections Control Signals HV Pulser GRD Pump Treatment Cooling Chamber Coil Subjecting food to multiple l high h voltage short electric pulses - static or continuous

57 PEF Focus Today Two study areas: preservation & extraction Research generally limited to liquid products Eggs, milk and fruit juices Solid treatment to enhance poration Typical conditions for PEF Electric field intensity: 5-60 kv/cm Current: 20 A, Voltage: 8 kv Frequency of pulses: Hz Pulse duration: ms Number of pulses: Total treatment time: ms Temperatures: room - 50C

58 PEF System

59 Concluding Remarks Considerable interest in minimal processing alternatives for quality preservation Many methods exist Requires proper understanding of the process-product product characteristics

60 Thank you for your attention!