selection of foodstuffs
TRANSCRIPT
SELECTION OF SELECTION OF FOODSTUFFSFOODSTUFFS
Ingrid SteinerVienna University of Technology
Institute of Chemical Engineering
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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SELECTION OF FOODSTUFFS -Fundamentals
To classify foodstuffs/food groups with respect to those physico-chemical properties which can be expected to influence the behaviour of food as a sorption matrix for the uptake of migrants. To select a list of approximately 15 to 20 (max. 25) foodstuffs which can be considered to berepresentative based on the following criteria:
with respect to the spectrum of migration relevant physico-chemical parametersaccording to up-to-date and available food consumptionstatistics and market share. This should at least includethe foodstuffs most frequently consumed and deservetherefore consideration at higher priority.
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Consumption of foodstuffs in Europe
Graph by C. Simoneau et al., EC JRC, IHCP
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Establishing the final list of foodstuffs
From the aspects considered before the two representative and established lists of foodstuffs may vary to a small or even large extent. Some harmonisation was necessary to end up with one representative list which fulfilled the best the purpose of this project idea which is to model migration into foodstuffs for exposure estimates as broad and general as possible.
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Categories of food
Aqueous and acidic foodsFatty foodsDry foods
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Aqueous and acidic foodstuffs
Orange juice, unsweetened, fresh with pulpApple sauceTomato ketchupCarbonated beverage (cola drink)BeerWineMilk, consumer milk, min. 3,5% fat
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Fatty foodstuffs (I)
Margarine (80% fat content)Mayonnaise (80% fat content)Cheese Philadelphia(~70 % fat in dry matter)Cheese Gouda, 45 % fat content (in dry matter)Cheese sauce (18,5% fat)Cottage cheese (fresh cheese, ~10 % fat content in dry substance)
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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Fatty foodstuffs (II)
Whipping cream, UHT (~30% fat)Condensed milk (10% fat)Yoghurt drink, (0,9 % fat)Chocolate, dark, milk free, min. 40 % cocoa content (30% fat)Chocolate spread (25% fat)Meat, lean pork meat (minced, fat content ≤ 5%),mixed with lard to get fat contents up to 50%Salmon
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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Dry foodstuffs
Milk powderButter toast (4% fat)Wheat flourRiceHoney
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Physico-chemical specifications of selected foodstuffs
establish the representative physico-chemical parameters for the foodstuffsfinally selected before
The measurements were done in the majority of cases according to standard or state-of-the-art methods or were adopted from the labelling of the foodstuff.
⇒ basis for a representative and general applicability of the model
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Physico-chemical parameters in detail
DensityMass-to-volume ratio(“Schüttgewicht”)StructureParticle size
Median particlediameterMean specific surfacearea
Water contentSolids (dietary fibre)CarbohydratesProteinsFatAlcoholAsh (minerals)pH
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Data of aqueous and acidic foodstuffs
Food Water(%)
Fat(%)
Solids(%)
CH(%)
Protein(%)
0,15 ---
0
1
---
---
3,3
Applesauce
79 0 --- 21 3,60 1,10
0,20
---
---
---
3,5
pH Density
Orange juice
87,1 12,9 12 3,95 1,05
Tomatoketchup
64,5 35,5 29 3,20 1,17
Cola drink 89 11 10,6 3,10 1,05
Beer (EtOH 5%)
91,3 3,7 --- 3,90 1,01
Wine(EtOH 11,5%)
86,7 1,8 --- 3,25 1,00
Milk 88,5 11,5 4,7 5,35 1,03
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Data of fatty foodstuffs (I)Food Water
(%)Fat(%)
Protein(%)
CH(%)
pH Density
Margarine 19,3 80 0,2
0,9
Gouda 48,0 2950 FDM
21 2 5,70 1,11
6,5
12,7
9,5
0,3 4,20 0,88
Mayonnaise 16,8 82 0,3 3,60 0,86
CheesePhiladelphia
61,8 2868 FDM
3,1 5,00 1,02
Cottage cheese
82,0 2,210 FDM
3,1 4,30 1,06
Cheese sauce 62,4 19 7,9 5,00 1,14
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Data of fatty foodstuffs (II)
Food Water(%)
Fat(%)
Protein(%)
CH(%)
pH Density
Whippingcream
60,0 32,0
9,0
0,9
31,3
30,0
8,0 --- 5,50 1,00
Condensedmilk
28,6 8,2 54,2 5,55 1,29
Yoghurt drink
83,6 2,7 12,8 3,70 1,06
Chocolatedark
1,8 2,7 53,1 --- 1,34
Chocolatespread
2,0 7,0 59,0 6,20 1,32
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Data of fatty foodstuffs (III)
Food Water(%)
Fat(%)
Protein(%)
pH
Pork meat 65 - 72 1,4 - 5 17,5 – 21,6 5,80
Chicken meat(breast)
70 - 74 ~ 6 ~ 22 6,30
Salmon 59 - 66 ~ 14 ~ 20 6,60
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Pork meat: Correlation between fatcontent and density
Correlation fat/density for pork meat
0,5
1
1,5
0 20 40 60 80 100 120
Fat content (%)
Den
sity
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Data of dry foodstuffsFood Water
(%)Fat(%)
Protein(%)
CH(%)
Density„Schüttgewicht“
Med. particlediameter(µm)
Mean spec. surfacearea (cm2/g)
Milk powder
3,0 26,0 26,0 39,0 0,48
0,60
0,23
0,84
1,44
13
Wheatflour
14,0 1,0 10,6 74,0
125
75
---
5,1-5,7 mm(76 %)
22
Butter toast
44,0 4,0 4,0 47,0 ---
Rice 12,0 1,4 6,8 79,8 11
Honey 17,0 --- 3,0(incl. ash etc.)
80,0 --- ---
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Milk powder – particle size
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Special structures and matrices of somefoodstuffs
Orange juiceMilkCheeseOther milk productsPowders
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Orange juice and other foodstuffscontaining fibres
Adsorption effects of pectin and otherunsoluble substances
⇒ Higher migration values also of lipophilic substances than expected
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Milk
Electron micrograph of homogenized milkfat globulesFrom: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
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Heated milk
Casein micelle in heated milk Casein micelles forming a chain
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
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Milk powder
Dents in the large particle have been caused by small hard dry particles
A small particle (surrounded by a 'crater' rim) has been captured by a large particle.
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
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Difference of milk powders depending on drying process
Instantization results in agglomeration of powder particles
Roller-dried milk particles are produced as fragments of a dried milk sheet.
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
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Influence of cheese production on structure of milk particles
Junctions in stirred curd cheeses (e.g. Gouda)Pictures from: http://www.foodsci.uoguelph.ca
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Cream (soft) cheese
Microstructure of Cream cheese made from high-fat cream and acid-coagulated hot milk Fat globules (brown), curd (which shows the core-and-shell ultrastructure of casein particles - dark blue), aqueous phase (yellow).
Microstructure of traditional Cream cheese Fat globule clusters (dark yellow) are covered with protein (dark blue) in the aqueous medium (light yellow)
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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„Cottage“ cheese
Distinct casein micell clusters; green: bacteria
Picture from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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Casein micelle chains in yoghurt and micelle aggregates in cheese
Yoghurt
Cheese
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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Structure of yoghurt depending on content of milk solids
20%Milk solids content 10% 15%
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
I. Steiner, FOODMIGROSURE - Baveno 27.9.06
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Matrix of yoghurts produced in a different way
Yoghurt made from unfortified milk Yoghurt made from milk fortified with whey proteins
Pictures from: http://distans.livstek.lth.se:2080/microscopy/foodmicr.htm
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Questions
Is there a correlation between themigrational key parameters diffusioncoefficients and partition coefficients of theselected model migrants and foodcategories specified by physico-chemicalproperties?Have food categories and theircorresponding model migrants to berevised caused by measured migrationalvalues?
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Thanks for excellent cooperation to
Peter VolanskyHerbert Hafner
Catherine Simoneau (WP 2 and 7)All project partnersCoordinator Roland Franz and his team
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Thank you for your attention!
Is it safe?