domestic cooking en

EXAMINATION OF THE EFFECT OF DOMESTIC COOKING ON ACRYLAMIDE LEVELS IN FOOD : 

EXAMINATION OF THE EFFECT OF DOMESTIC COOKING ON ACRYLAMIDE LEVELS IN FOOD Rachel Burch Leatherhead Food International

Objectives: 

Objectives To compile a list of foods relevant to home cooking that are high in asparagine, taking into account levels of consumption To examine the effect of cooking on acrylamide levels of less complex foods (i.e. vegetables) To examine varietal effects in potatoes

Total quantities (grams) of vegetables and vegetable products consumed in 7 days (consumers only): 

Total quantities (grams) of vegetables and vegetable products consumed in 7 days (consumers only) NDNS data, 2002

Asparagine and glutamine levels: 

Asparagine and glutamine levels

Task 3a: 

Task 3a Potatoes cooked from fresh and from frozen Baked, boiled, roast, saute, microwave “baked” from fresh Boiled, roast, saute from frozen Onions cooked from fresh and from frozen Boiled, baked, fried from fresh and frozen

Task 3a – Potatoes: 

Task 3a – Potatoes

Task 3a – Onions: 

Task 3a – Onions

Task 3c – Cyclic re-use of frying oils: 

Task 3c – Cyclic re-use of frying oils Five different oil types Five cookings in each oil Initial cookings to same colour, to determine fry time for each oil. Subsequent cookings for the same length of time Oil temperature 190ºC (except lard: 175ºC)

Use of different cooking oils: 

Use of different cooking oils

Re-use of cooking oils: 

Re-use of cooking oils

Re-use of cooking oils - conclusions: 

Re-use of cooking oils - conclusions Preliminary data suggests: Some differences in acrylamide levels in chips cooked in different oils Some indication that acrylamide levels increase in chips cooked in re-used rapeseed oils

Task 3d – Effect of pre-treatment: 

Task 3d – Effect of pre-treatment Chips Washing, storing in water for 30 mins, storing in water for 2 hours Samples prepared in triplicate, chips cooked for same length of time Roast potatoes Washing, storing in water for 30 mins, storing in water for 2 hours, par-boiling Samples prepared in triplicate, cooked for same length of time except for par-boiled

Task 3d – Effect of pre-treatment - Chips: 

Task 3d – Effect of pre-treatment - Chips

Chips – correlation with colour: 

Chips – correlation with colour green red

Chips – correlation with colour: 

Chips – correlation with colour L Value Dark Light

Pre-treatment – Chips – glucose removed: 

Pre-treatment – Chips – glucose removed

Task 3d – Effect of pre-treatment – roast potatoes: 

Task 3d – Effect of pre-treatment – roast potatoes

Pre-treatment – roast potatoes – glucose removed: 

Pre-treatment – roast potatoes – glucose removed

Effect of variety - chips: 

Effect of variety - chips

Effect of variety – Roast potatoes: 

Effect of variety – Roast potatoes

Effect of variety – baked potatoes: 

Effect of variety – baked potatoes

Conclusions – factors affecting acrylamide formation in domestic cooking: 

Conclusions – factors affecting acrylamide formation in domestic cooking Type of cooking Acrylamide formed in roasted, sautéed, oven baked potatoes, higher levels found in potatoes cooked after freezing Not formed in boiled or microwaved potatoes Formed in fried onions, onions baked from frozen Not formed in onions baked from fresh, or boiled Pre-treatments Soaking for two hours, or par-boiling led to greatest reductions Indication that some pre-treatments affect fat content

Conclusions – factors affecting acrylamide formation in domestic cooking: 

Conclusions – factors affecting acrylamide formation in domestic cooking Chip colour correlates to acrylamide levels, roast potato colour does not Roast potatoes were not of uniform size and shape Variety Some varieties result in higher acrylamide levels relative to other varieties cooked using the same method