Technologies the production of milk-based ingredients Nick Adamson Ph.D. Sub-category Manager Milk & whey based ingredients
Agenda Ingredient product overview Our goals as ingredient processors Technology overview Closer look at some select technologies Heat treatment and centrifugation Membrane processes Demineralisation processes Evaporation and drying Key Points
Ingredients direct from milk Whole Milk Concentrates and Powders Cream Skim Milk Products Amorphous Milk Fat Caseins and caseinates Milk Protein Concentrate Butter Direct acid caseins Micellar Casein Native Whey Frozen Cream Rennet caseins Milk UF permeate Biological caseins Milk WPI D90 Native Whey
Ingredients direct from whey Whey Powders Whey Protein Products Permeate Products Standard De-lactosed (DLWP) WPC35-59 Lactose Permeate powder Demin 40 WPC60-80 Lactose Edible Mother Liquor Demin permeate Demin 70 WP Isolate Lactose Refined Demin 90 Hi Fat WPC Lactose Pharma
Composition Value add through protein purification Product TOP/TS Casein/TOP Ash/TS Lactose/TS SMP 33-34 76.5 8 55 MPC85 85 76.5 7 8 MCC 90 92 6.5 2.3 MCI 90 97 6.5 0.3 SWP 13 9.7 75 WPC35 35 7 50 WPC80 80 2 10 WPI 90 2 7 DWP40 13 6 DWP70 13.5 2.5 DWP90 13.5 1
Where do the solids go?
Processing Goals - Ingredients Not an exhaustive list but... Safe Food Pathogens Foreign Matter Package security Total Viable Counts Thermodurics & spores Superior Functionality Nutrition, flavour, colour, appearance Composition Protein purity and denaturation level Wettability, dispersability, solubility, BD Water binding, viscosity etc Maximise profit / tonne milk solids Sustainability & Low Cost Water & waste minimisation Costs esp, transport and energy Material usage Operability Asset Utilisation Maximise capacity Flexibility Minimise non-value add infrastructure
Many Technologies Employed Milk Derivatives Whey Derivatives Unit Operations Clarification Separation WMP SMP High Free Fat WMP MPC Bactofugation Option Option Option Option Option Pasteurization RO or HiRO MCC / MCI Native WPI Nanofiltration (NF) Option Option Electrodialysis Ion Exchange Wet Blending Ultrafiltration Microparticulation Microfiltration Ultrafiltration-Diafiltration High Concentration NF De Calcification Decolorisation Whey Powder Evaporation Option Option Crystallization Tanks Washing Decanting Sieve Centrifugation Drying (Spray WB / TWB) Option Option Drying (Spray TFB) Option Option Option Option Option Option Option Option Option Drying (Fluid Bed) Dry Addition Fluid Bed Post-crystallization Option Option Powder Handling Milling Option Option Powder transport & storage Packing 25 kg Packing Bulk Bag DeLactosed Whey DWP40 DWP70 DWP90 WPC35-60 Option WPC60-80 WPI Permeate Powder Option Lactose Edible Mother Liquor Option Option Lactose Pharma Microparticulated Whey Option
Focus for Today Milk or Whey Heat Treatment Centrifugation Membrane filtration Spray Drying Crystallisation Evaporation Demineralisation technologies Powder Handling
Heat treatment and centrifugation applications Index
Heat Treatment Managing the competing objectives of killing bacteria and preserving product quality (protein denaturation, flavour, colour) Psychotrophic growth Thermophilic thermoduric danger zone Mesophile pasteurisation Spore kill starts 7 C 15 C 40 C 45 C 62 C 72 C 90 C 118 C Whey protein denaturation reversible BSA denaturation irreversible Β-LAC denaturation irreversible α-lac denaturation irreversible
Centrifugation Clarification Impurity removal for milk Cheese fines recovery Fat Separation Hot & cold milk separation Whey separation Butteroil & AMF Spore & Bacteria Removal Milk for ESL, powder and cheese Whey cleaning
Membrane Filtration Index
Basic principles of filtration Retentate Feed MF Retentate Permeate/ Feed UF Retentate Permeate/ Feed NF Retentate Permeate/ Feed RO Pure water Bacteria, spores, fat globules Casein, whey proteins Lactose, acids, NPN Minerals Water
Overview of Filtration Processes Microfiltration Ultrafiltration Nanofiltration Reverse Osmosis Fractionation of casein and whey proteins in skim milk WPC 35 (8-10 % TS) WPC50-75 (15-25% TS) Skim 26% TS, 20% desal Sweet whey 30% TS, 40% desal Skim milk 34% TS Whole milk 30% TS WPC80-84 (30-33% TS) Acid whey 21% TS, 25% desal Sweet whey 30% TS WPI (MF permeate) Salt whey desalination Acid whey 17-20% TS Fat separation for WPI 90+ % MPC42-MPC85 MPI/MCI MF Retentate Native WPC80 Sweet UF permeate 25% TS, 40% desal Acid UF permeate Sweet UF permeate 25% TS Acid UF permeate 18-22% TS Sweet buttermilk 26% TS 22% TS, 30% desal Bacteria removal from skim milk, whey and cheese brine Sweet buttermilk (retentate for food ingredients, powder) Special products, yoghurt, desserts WPC80 36% TS WPI 38% TS WPC35 32% TS Cleaning of CIP solutions White water concentration RO & NF permeate polishing Evaporator condensate
NPN losses associated with concentration Value assumptions Whey 511/tonne TS 3,927/tonne TOP Skim 1,667/tonne TS 4,065/tonne TOP
Electrodialysis and ion exchange applications Index
Electrodialysis
Electrodialysis Typically operated between 10-45 C Effluent treatment, electrical power, cleaning chemicals and steam make up operating costs Thin membranes give low electrical resistance and reduce cost Fouling of membranes by proteins and calcium phosphate contribute to maintenance costs Electro-dialysis is best below 70% demineralisation where operating costs are competitive with ion-exchange Very good for removal of organic acids; typically D55-60 gives acceptable product from acid whey
Ion Exchange Cation Exchange: R H + Na+ = R Na + H+ (resin in H+ form) Anion Exchange: R OH + Cl = R Cl + OH (resin in OH form) Sulphonic groups -SO3-H+ (strong acid cation exchanger) Carboxyl groups -COO-H+ (weak acid cation exchanger) Quatenary amine N+ OH- (strong base anion exchanger) Tertiary amines NH+ OH- (weak base anion exchanger)
Demineralisation Processes D30-40 NF D50- D70 NF ED D50- D70 IEX1 NF ACID HTST STD D90 Acidic IEX1 NF ED ACID HTST IEX2 STD D90 Basic NF ED IEX STD
Product Quality and Yields Eurodia acidic D90 process Parameter ph 6.4 6.7 Fat (% on DS) < 1.25 Total protein (% on DS) < 100 Ash (% on DS) < 0.90 Calcium (mg/100g DS) < 100 Magnesium (mg/100g DS) < 50 Sodium (mg/100g DS) < 20 Potassium (mg/100g DS) < 300 Chloride (mg/100g DS) < 20 Phosphorus (mg/100g DS) < 160 Parameter Typical Yield Total solids 85% Total protein 84% Whey proteins 97% NPN 44% Lactose 97.5% Fats 98% Organic acids 4% Bacteria Count Mesophilic Bacteria < 5000 cfu/ml Thermophilic Bacteria < 100 cfu / ml
Typical Operating Costs D90 process Cost per Tonne D90 Hydrochloric acid 24 Caustic Soda 11 Compressed Air 0.4 Ultrasil 15 Power 10 Chilled Water 8 Steam 3 Resins, membranes etc 30 101 Effluent costs dependent on the disposal options available to the site
Evaporation and Drying Index
Falling Film Vacuum Evaporation Typical Operating Total Solids Product Feed TS Concentrate TS Whole milk 12.5 25% 52% (MH) Skim milk 9 18% 50% (MH) Sweet whey 18-23% 64% D40 D90 18 22% 58-62% UF permeate 18 25% 67% MPC85 18% 26% WPC35 10% 45% WPC80 / WPI Not used 36-40% (NF) MCC 10% 21-23%
Membrane pre-concentration before evaporation Balancing energy consumption against quality & yield loss Cost Item ( /tonne water removed) Skim RO 18% Skim RO 30% MVR Skim Electrical Power 0.7 0.7 1.2 Steam 0.1 0.1 0.7 NPN Loss 1.2 1.6 CIP chemicals 0.7 0.7 0.4 Water & Waste 0.2 0.3 0.3 Maintenance % 3% RV 0.4 0.4 0.2 Depreciation @ 5% 0.1 0.2 0.4 Interest @ 5% 0.1 0.1 0.2 Total 3.7 4.3 3.6
Spray Drying Product Range Flexibility
Key Points Normally protein loss and value for improved functionality outweigh energy savings; be careful when optimising. RO pre-concentration worthwhile but consider protein loss Acidic ion exchange superior for D90 Distinguish between routine flexibility and emergency flexibility. Dryers and evaporators can be quite flexible if designed for upfront but allow time for this Line optimisation requires balancing complex and competing priorities for each unit operation and the specific applications