ACRYLAMIDE REDUCTION IN FRIED POTATO SLICES AND STRIPS BY USING ASPARAGINASE IN COMBINATION WITH CONVENTIONAL BLANCHING

Transcription

1 ACRYLAMIDE REDUCTION IN FRIED POTATO SLICES AND STRIPS BY USING ASPARAGINASE IN COMBINATION WITH CONVENTIONAL BLANCHING Franco Pedreschi Plasencia Departamento de Ingeniería Química y Bioprocesos Pontificia Universidad Católica de Chile

2 SCHEMATIC REPRESENTATION OF THE IMMERSION FRYING OF A POTATO STRIP ( FRENCH FRY ) HEAT TRANSPORT Convection Evaporative cooling Conduction CORE CRUST MASS TRANSPORT Oil Water vapor 2

3 Chip Raw potato FRYING French fry CRUST CORE 3

4 CRUCIAL CHANGES IN POTATO TISSUE DURING FRYING High heat transfer coefficients: very fast cooking and drastic changes not only in physcal properties but also in microstructural properties. Development of attractive sensorial properties in procesed foods for the consumer: crispness, flavor, color, texture & aroma. Maillard Reaction color, acrilamida, aroma, etc. Oil uptake and Acrylamide formation. Microstructural changes. 4

5 FOODBORNE RISKS FOR HUMAN HEALTH (i) Inherently present in foods (e.g. natural toxins, alergenics, intolerable compounds, etc.). (ii) Related to environmental contaminants (e.g. organic persistent contaminants, heavy metals, radionucleotides). (iii) Related to microbial activity (e.g. infectious agents, bacterial toxins, biogenic amines, mycotoxins). (iv) Related to animal production practices (e.g. antibiotics, hormones, melanine). (v) Result of excesively heating during Food processing (e.g. acrylamide, furan, heterocyclic amines). 5

6 NUTRITIONAL SAFETY

7 MAILLARD REACTION 7

8 NON-ENZYMATIC BROWNING

9 HEAT PROCESSING IN FOODS Excessive heating could increase micribiological safety but at the same time would decrease the chemical safety O V NH 2 Acrylamide

10 ACRYLAMIDE FORMATION IN FOODS 10

11 STARCHY FOODS PROCESSED AT HIGH TEMPERATURES 11

12 MOTIVATION Acrylamide: Compound potentially carcinogenic for humans (IARC, 1995) o Consumer trends and food preferences o Information necessity. It is a challenge to minimize acrylamide levels in starchy foods heated excessively while maintaining as intact as possible the attractive and desired sensorial attributes by the consumers.

13 MAIN ACRYLAMIDE FORMATION MECHANISM Reducing sugars Asparagine Maillard Reaction Acrylamide formation in foods O V NH 2 Acrylamide

14 ACRYLAMIDE LEVELS (µg kg -1 ) IN FOODS Food Indicative value (µg kg -1 ) No. a Mean b (µg kg -1 ) perc. (µg kg -1 ) No. a Mean b (µg kg -1 ) 90 perc. (µg kg -1 ) No. a Mean b (µg kg -1 ) 90 perc. (µg/kg) No. a Mean b (µg kg -1 ) 90 perc. (µg kg -1 ) Biscuits Crackers Gingerbread Infant biscuit/rusk Other biscuits etc Wafers Bread Crisp bread Bread soft Breakfast cereals Cereal-based baby food Potato products Potato crisps French fries Homecooked potato products: Deep fried Not specified Oven baked (Pedreschi et al. 2013)

15 MITIGATION TECHNOLOGIES OF AA FORMATION IN FOODS Temperature Acrylamide Mitigation Technologies Changes in Process Parameters Blanching Solutions NaCl Organic Acids Di-Tri valents Cations Several Technologies Combined Microorganisms Aminoacids Reduction of Acrylamide Precurssors Asparaginase Genetic Modification Non Reducing Sugars (Mariotti et al. 2011)

16 ASPARAGINASE MITIGATION OF DIETARY ACRYLAMIDE 16

17 IN USA, ACRYLAMIDE POTENTIALLY RIK IN FOODS HAVE BEGUN TO BE REGULATED: CALIFORNIA S PROPOSITION 65 French fries...contain acrylamide, a chemical known to the State of California to cause cancer 17

18 ELABORATION OF PAR FRIED POTATOES Raw strips Blanching 75 C x 10 min Blanched Strips Drying 75 C x 10 min Par-frying 175 C x 1 min Freezing -30 C x 2 dias Final frying 175 C x 3 min 18

19 Acrylamide content (mg/kg) ACRYLAMIDE CONTENT IN PAR FRIED AND FINAL FRIED POTATO STRIPS C: Control B: Blanching 75 C, 10min D: Air Drying 85 C, 10min P: Par frying 175 C x 1 min F: Frying 175 C x 3 min C CD CDP CDPF BDPF Pre-treatments

20 Acrylamide content (mg/kg) Acrylamide content (mg/kg) EFECT OF ASPARAGINASE IMMERSION OVER ACRYLAMIDE FORMATION IN RAW AND BLANCHED POTATO STRIPS AFTER FRYING C: Control B: Blanching 75 C, 10min E1: Asp 40 C x 20 min E2: Asp 50 C x 10 min E3: Asp 60 C x 10 min CDPF CE1DPF CE2DPF CE3DPF Treatments (ASP): ASNU/l BDPF BE1DPF BE2DPF BE3DPF Treatments

21 Glucose content (g/100 g dry basis) Asparagine content (g/kg dry basis) Acrylamide content (mg/kg) EFECT OF BLANCHING BEFORE ASPARAGINASE IMMERISION OVER ACRYLAMIDE FORMATION IN FRIED POTATO STRIPS BDPF BE1DPF BE2DPF BE3DPF Treatments 2,40 18,00 1,80 12,00 1,20 6,00 0,60 0,00 C B BE1 BE2 BE3 0,00 C B BE1 BE2 BE3 Treatments Treatments 21

22 2500 EFECT OF BLANCHING BEFORE ASPARAGINASE IMMERISION OVER ACRYLAMIDE FORMATION IN FRIED POTATO CHIPS Acrylamide content ( mg/kg) A: Control B: Blanching 85 C, 3.5min C: C + Asp 50 C x 20 min D: B + Asp 50 C x 20 min E: B + 50 C x 20 min Frying: 1755 C, 3 min (ASP): ASNU/l 0,12 0 A B C D E Pre-treatments 6 0,10 5 Glucose content (g/kg) 0,08 0,06 0,04 Asparagine content ( g/kg) ,02 1 0,00 A B C D E Pre-treatments 0 A B C D E Pre-treatments 22

23 PAPERS Acrylamide reduction in potato chips by using commercial asparaginase in combination with conventional blanching. / Pedreschi, Franco; Mariotti, Salomé; Granby, Kit; Risum, Jørgen. Lebensmittel - Wissenschaft und Technologie, Vol. 44, No. 6, 2011, p The effect of asparaginase on acrylamide formation in French fries. / Pedreschi, F.; Kaack, K.; Granby, Kit. Food Chemistry, Vol. 109, No. 2, 2008, p

24 CONCLUSIONS Soaking in an asparaginase solution of blanched potato strips was an effective method to diminish acrylamide formation after frying. Asparaginase reduced significantly the amount of asparagine. Blanching improved the action of commercial asparaginase in reducing asparaginase concentration in potato pieces leading to potato chipswith lower acrylamide contents. 24

25 Acrylamide content (µg/kg) ASPARAGINASE MITIGATION IN CHILEAN BREAD HALLULLA Dough preparation Baking or cooking Cooling LOD Asparaginase content (ppm/kg flour)

26 ASPARAGINASE MITIGATION IN SOPAIPILLAS Addition of L-asparaginase to the dough decreased asparagine levels for all resting times and enzyme concentrations defined in this research (acrylamide decreasing up to 85%). 26

27 AKNOWLEDGMENTS Novozymes FONDEF Project D10/110 FONDECYT Project Danish for Food, Agriculture and Fisheries Project: Reduction of the formation and occurence of acrylamide in food 27