Improve the performance of your retort flexible film FLEXPACKCON 2018 Phoenix, October 31 st 2018 Sergi Salvà Sàez Technical Development Manager UBE America Inc. 1
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 2
Retort process Definition : Retort is a sterilization process in autoclave under high temperature and pressure. This process is also used in the food industry to extend the shelf life of goods T 121ºC t 30 min 3
Retort food Ready to eat meals Vegetables Fish Pet food 4
Requirements for retort packaging : Resist treatment temperatures and humidity Do not undergo undesirable changes (color, appearance, transparency) Heat-resistant seal system during heat treatment Do not have migrations Facilitate thermal transfer Barrier properties appropriate to the estimated Shelf-life of the food? 5
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 6
PA & EVOH barrier vs %RH PA EVOH 60 OTR (cc m 2 /day) @ 23ºC 50 40 30 20 10 OTR (cc m 2 /day) @ 20ºC 0 0 20 40 60 80 100 Relative Humidity (% RH) PA6 PA6/6.6 Source : EVAL brochure High moisture content of the barrier layer = Lower Oxygen barrier 7
Moisture absorption in autoclave In autoclave during retort process T 121ºC On the shelf after retort process T = Room temp. P : High t 30 min P : atm. t : long storage Moisture absorption of the barrier layers Slow moisture release (drying) 8
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 9
Concept 10
Moisture barrier of polymers In autoclave during retort process T 121ºC On the shelf after retort process T = Room temp. P : High t 30 min P : atm. t : long storage PP / Tie / PA / Tie / PP PP / Tie / PA / Tie / PP PP / Tie / PA / Tie / PP PP / Tie / PA / Tie / PP Moisture absorption of the barrier layers Slow moisture release (drying) 11
Moisture barrier of polymers WVTR @ 40ºC, RH 90% PP as OUTER LAYER (after retort) WVTR (g/100in 2 day) 12 10 8 6 4 PP, 0.7 2 0 PP Test according JIS Z-0208 / ASTM E-96 NYLON, 11 NYLON PP / Tie / PA / Tie / PP PP / Tie / PA / Tie / PP PA as OUTER LAYER (after retort) PA / EVOH / PA / Tie / PP PP / Tie / PA / EVOH / PA 12
Moisture dependence of NYLON 8 7 6 5 4 3 2 1 0 UBE NYLON COPOLYMER @ 23 ºC, RH 50% WET WET, 7.5 DRY, 0.5 DRY Wet : HIGHER WVTR, QUICK DRY PA / EVOH / PA / Tie / PP PP / Tie / PA / EVOH / PA Dry : LOWER WVTR, PROTECTION WET conditions: ASTM E-96 Water method DRY conditions: ASTM E-96 Desiccant method PA / EVOH / PA / Tie / PP PP / Tie / PA / EVOH / PA 13
Film structures Symmetrical structures Conventional Asymmetrical structures Medium barrier PP / Tie / PA / Tie / PP PA / Tie / PP / PP / PP High barrier PP / Tie / EVOH / Tie / PP PP / Tie / PA / EVOH / PA / Tie / PP PA / EVOH / PA / Tie / PP For the study : Total film thickness : 100µm PA layer thickness : 30% EVOH layer thickness : 10% 14
Oxygen Transmission Rate (by OTR) Symmetrical structures Conventional Asymmetrical structures PP / Tie / PA / Tie / PP Analysis time (OTR stabilization) PA / Tie / PP / PP / PP Analysis time (OTR stabilization) Medium barrier OTR (cc m 2 / day) 150 100 50 Before retort After retort 14 days OTR (cc m 2 / day) 150 100 50 Before retort After retort 4 days 0 0 High barrier OTR (cc m 2 / day) PP / Tie / EVOH / Tie / PP 4 2 Before retort After retort Analysis time (OTR stabilization) 18 days OTR (cc m 2 / day) PA / EVOH / PA / Tie / PP 4 2 Before retort After retort Analysis time (OTR stabilization) 6 days 0 0 Autoclave conditions : T=125ºC, t =30min Room conditions : T=23ºC, RH =50% t=24h Testing conditions : T=23ºC, RH (O 2 ) =50% - RH (N 2 ) = 90% Films don t recover 100% initial O 2 barrier after retort treatment Faster drying = Faster barrier recovery in asymmetrical structures 15
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 16
Evaluation methodology 1- Pouches preparation: - Tubular film (only 2 sealing of the pouch) - Always same dimensions 2- Sensors fixed in the packages: - For the non-invasive optical measurement 17
Evaluation methodology 3- Tomato sauce filling: - Always same sauce and same amount 4- Introduction of temperature and pressure recorder: 18
Evaluation methodology 5- Pouches closing: - Vacuum - Introduction of N 2 in the head space - Sealing 6- Autoclave treatment: 19
Evaluation methodology Autoclave conditions : T = 121ºC t = 30 min 20
Evaluation methodology 7- Storage conditions: - Temperature : T = 23ºC, - Relative humidity : RH = 50% - Time : t = up to 6 months 21
Oxygen Permeation (optical measurement) 22
Oxygen Permeation (optical measurement) Oxygen permeation after retort treatment Oxygen content in head space (%) 20.00 18.00 16.00 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0.00 0 500 1000 1500 2000 2500 3000 Time after retort treatment (h) Sym. Med. Barrier Sym. High. Barrier PP / Tie / PA / Tie / PP PP / Tie / EVOH / Tie / PP 23
Oxygen Permeation (optical measurement) Oxygen permeation after retort treatment Oxygen content in head space (%) 20.00 18.00 16.00 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0.00 0 500 1000 1500 2000 2500 3000 Time after retort treatment (h) Sym. Med. Barrier Asym. Med. Barrier Sym. High. Barrier PP / Tie / PA / Tie / PP PA / Tie / PP / PP / PP PP / Tie / EVOH / Tie / PP 24
Oxygen Permeation (optical measurement) Oxygen permeation after retort treatment Oxygen content in head space (%) 20.00 18.00 16.00 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0.00 0 500 1000 1500 2000 2500 3000 Time after retort treatment (h) Sym. Med. Barrier Asym. Med. Barrier PP Sym. / Tie / High. PA / Barrier Tie / PP PA Asym. / Tie / High PP / barrier PP / PP PP / Tie / EVOH / Tie / PP PA / EVOH / PA / Tie / PP 25
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 26
Structure : PA/Tie/PA/Tie/PP or PA/EVOH/PA/Tie/PP Outer layer : HYDROLISIS Resistant - UBE NYLON 5033FD8 Tested up to T=125ºC, t=3h Which UBE NYLON? UBE NYLON 5033B UBE NYLON 5033FD8 50 µm monolayer airblown film 27
Which UBE NYLON? Structure : PA/Tie/PA/Tie/PP PA/EVOH/PA/Tie/PP PP/Tie/PA/Tie/PP Middle layer : Elongation at break (%) 400 350 300 250 200 150 100 50 0 t = 0 Autoclave treatment at T=125ºC t = 30 min t = 2h PA6/6.6 UBE NYLON 5033B t = 4h t = 0 t = 30 min t = 2h t = 4h Functional PA6/6.6 UBE NYLON 5033FD8 Moderate conditions (up to 2h): UBE NYLON 1030B UBE NYLON 5033B UBE NYLON 5033FD8 Severe conditions (more than 2h): UBE NYLON 5033FD8 28
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 29
Application in carrot puree - Methodology Carrots peeling Carrots cutting Carrots cooking : T = 100ºC t = 45 min Carrots mashing Recipe preparation. Addition : 10% water Citric acid until ph = 5,2 Packing and sterilization : T = 121ºC t = 15 min P = 2,2 bar 32
Conditioning (storage) : Standard : T = 20ºC Accelerated : T = 40ºC Application in carrot puree - Evaluation Parameters : Color change ΔE ΔE Perception of change CIELab < 0,2 Not perceptible 0,2 0,5 Perceptible through close observation 0,5 1,5 Perceptible 1,5 3,0 Perceptible at a glance 3,0 6,0 Obvious 6,0 12,0 Significant > 12,0 Very significant 33
Standard Temperature (T=20ºC) Application in carrot puree - Color @ Standard Temperature (T=20ºC) ΔE 35 30 25 20 15 10 5 y = 0,2252x y = 0,2242x y = 0,0483x Sym. High barrier PP / Tie / EVOH / Tie / PP Asym. Medium barrier PA / Tie / PP / PP / PP Asym. High barrier PA / EVOH / PA / Tie / PP 0 0 20 40 60 80 100 120 140 Storage/Conditioning time (days) 35
Standard Temperature (T=20ºC) t = 0 (days) Application in carrot puree - Color Sym. High barrier PP / Tie / EVOH / Tie / PP t = 42 days Asym. Medium barrier PA / Tie / PP / PP / PP Asym. High barrier PA / EVOH / PA / Tie / PP t = 130 days 36
Accelerated Temperature (T=40ºC) Application in carrot puree - Color @ Standard Temperature (T=40ºC) ΔE 40 30 20 Sym. High barrier PP / Tie / EVOH / Tie / PP Asym. Medium barrier PA / Tie / PP / PP / PP 10 y = 0,1263x Asym. High barrier PA / EVOH / PA / Tie / PP 0 0 20 40 60 80 100 120 140 Storage/Conditioning time (days) 37
Accelerated Temperature (T=40ºC) Application in carrot puree - Color t = 0 (days) Sym. High barrier PP / Tie / EVOH / Tie / PP Asym. Medium barrier PA / Tie / PP / PP / PP Asym. High barrier PA / EVOH / PA / Tie / PP t = 25 days t = 93 days t = 130 days 38
Application in carrot puree - Shelf life Criteria : Color change not accepted by consumer (ΔE = 29) Calculated Shelf life : Sym. High barrier PP / Tie / EVOH / Tie / PP Asym. Medium barrier PA / Tie / PP / PP / PP Asym. High barrier PA / EVOH / PA / Tie / PP 127-134 days 4 to 4,5 months 128-136 days 4 to 4,5 months 308-340 days 10 to 11 months Oxygen permeation results could be extrapolated to shelf life New concept increases more than two times shelf life of the product 39
Agenda Retort Process & Food O 2 Barrier vs moisture New retort packaging concept Evaluation methodology & Data Which UBE NYLON for retort? Case study Conclusions 37
Conclusions 1) Medium barrier asymmetrical films (PA/Tie/PP/PP/PP) : Good alternative to current high barrier symmetrical films (PP/Tie/EVOH/Tie/PP). Besides they offer superior mechanical and optical properties. 2) High barrier asymmetrical films (PA/EVOH/PA/Tie/PP) : Solution to extend significantly the shelf life of the foodstuffs. Besides they offer higher mechanical and optical properties. 3) UBE NYLON 5033FD8 (unique material in the market) offers the possibility to place PA in outer layer of retort packaging. 38
Thank You very much for your attention Sergi Salvà Sàez Technical Development Manager UBE America Inc. E-mail: s.salva@ube.com 39