FOOD ADDITIVES - PowerPoint PPT Presentation

Loading...

PPT – FOOD ADDITIVES PowerPoint presentation | free to download - id: 69aeaf-MTc2N



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

FOOD ADDITIVES

Description:

FOOD ADDITIVES The GRAS list: Generally Regarded as Safe List Anti-caking agents: Ca silicate SiO2 Iron ammonium citrate Acids/bases/buffers: acetates, citrates ... – PowerPoint PPT presentation

Number of Views:24
Avg rating:3.0/5.0
Slides: 23
Provided by: RegMit5
Learn more at: http://web.uvic.ca
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: FOOD ADDITIVES


1
FOOD ADDITIVES The GRAS list Generally
Regarded as Safe List
Anti-caking agents Ca silicate SiO2 Iron
ammonium citrate Acids/bases/buffers acetates,
citrates (left) , lactates, phosphates, tartara
tes, sorbates (middle) Emulsifiers
(surfactants) mono- and diglycerides of fatty
acids alcohols like sorbitol (right)
2
  • Preservatives benzoates, propionates, sorbates,
    parabens
  • Anti-oxidants ascorbic acid, BHA, BHT,
  • lecithin, SO2 and sulphites
  • Flavour enhancers MSG, maltol
  • Sweeteners Aspartame, Mannitol, Saccharin,
    Sorbitol
  • Flavourings amyl butyrate (pear), carvone
    (spearmint), citral (lemon),
  • Ethyl vanillin (vanilla), geraniol (rose), methyl
    anthranilate (grape),
  • methyl salicylate (wintergreen), eugenol
    (allspice)

3
PRESERVATIVES prevent bacteria and oxidation
dry and/or use salt/sugar OR add a
BACTERICIDE SODIUM BENZOATE 0.1 Used under
acidic conditions pie fillings, jams, syrups,
pickles, relishes, olives, margarines, jellies,
non-alcoholic beverages (found naturally in
cranberries)
SODIUM PROPANOATE (PROPIONATE) 0.3 CH3CH2COO-
Na Used under non-acidic conditions bread,
chocolate, cheese, pie-crusts (found naturally in
Swiss Cheese) ACTION OF BOTH coats cell walls,
stop passage of nutrients in or out, microbe
dies from starvation
4
BACTERIOSTATS (FUNGISTATS) Prevent the growth,
dont kill SORBIC ACID AND THE SORBATES
used in breads, muffins, cheese, paint, rubber,
fish products, carbonated drinks...
5
PARABENS are used more in Europe
probably get incorporated in to Folic acid
instead of PABA very widely used in cosmetics
lipsticks, under-arm deodorants
6
PRESERVATIVES FOR MEATS NITRITES sodium
nitrite NaNO2 200 ppm LD50 0.18 g/kg ( 20 g
or so for me) Used in processed meats like
wieners, bologna, salami... NO2- inhibits
botulinus bacteria botulism toxin and also
reacts with myoglobin in meat to give a bright
pink color No nitrite, meat turns grey over time
(no harm in this) need about 10x amount for pink
than for botulinus inhibition Nitrates (NaNO3)
present in a wide variety of foods and water,
also can produce NO2- in presence of reducing
bacteria (see below)
7
Controversy In the stomach HNO2 forms, can
react with amines (R2NH) to produce NITROSAMINES,
R2N-NO Nitrosamines are highly carcinogenic (to
rats and other animals) Is this a major risk?
Probably NOT risk from botulism is much higher
and food contains some nitrates naturally
(lettuce, spinach, beetroot, celery _at_ 1000 ppm
peas, beans, onions _at_ 200 ppm and beer _at_ 25 mg
per beer) Average daily intake 100 mg of
nitrates, which on reduction gives 5 mg/mL of
nitrite in saliva and about 5 mg of nitrite in
the gut!
8
FRUITS SO2 (sulfur dioxide) gas OR sulphite
salts Used in dried fruits, wines, syrups,
jellies, dehydrated potatoes acts both as a
bleach and to kill bacteria
IRRADIATION 60Co g-emitter produce hydroxyl
free radicals that kill most micro-organisms and
inhibit many enzymes, prevent sprouting and
ripening
9
ANTI-OXIDANTS many are phenols
BHT BHA propyl gallate used in foods
containing oils and fats, up to 0.02 (egs.
Chips, cereals, breads)
10
FLAVOURS FRUITY are all esters, same as natural
ones
11
FLAVOUR ENHANCERS Potentiators dont have taste
themselves, but enhance the flavour of
others MSG Monosodium glutamate (0.2-0.9)
Sodium salt of the natural amino acid, made by
fermenting sugar beet molasses widely used in
meats, veg products, soya sauce, oriental
food Chinese Restaurant Syndrome sensitivity
to MSG (purportedly) causing weakness and
headaches recent evidence suggests it might be
histamines in the foods
12
So in part because of this see the 5'-nucleotides
used sodium inosinate, sodium guanylate
inosinic acid, Maltol (from pine
needles) used as sodium salt are used, look for
them in soups, savoury type foods. Jun 06 vine
ripe tomatoes (taste better) have more msg and
5nucleotides than gas ripened supermarket types!
(Chem World)
13
SWEETENERS Lead acetate is sweet but toxic!!
Pb(OCOCH3)2 - sugar of lead Not much logic as
to why things taste sweet SACCHARIN discovered
1879 300x sweeter than sucrose
14
Sweet Low (US) granulated sugar substitute
dextrose (3.6) and saccharin (36 mg per 1g
packet), cream of tartar and calcium silicate
(an anti-caking agent)
Banned in Canada since 1977 for causing cancer in
rats BUT Study used saccharin as 5 of diet
(equiv to 800 cans/pop per day!) 3/100 got
bladder cancer 14/100 2nd generation Use was
gt200,000 kg/year in Canada in soft drinks at time
of ban Not banned in US (already had banned
cyclamates) Some get a very bitter after-taste
and can tell immediately if saccharin has been
used!
15
CYCLAMATE (1930) 30x sweeter than sucrose, but
no after-taste
Reached peak in 1969 with 7 Mkg /y (US) soft
drinks Banned in US (1969) but not in Canada
rats got bladder cancer at absurdly high doses
Still approved in Canada, though not used in
soft drinks Sugar Twin sodium cyclamate in
Canada BUT saccharin in US
16
ASPARTAME (1965) 180x sweeter than sucrose,
texture of sugar
It is a peptide of the naturally occurring amino
acids phenylalanine and aspartic acid Use
100mg (4 kcal/g) 0.4 kcal)
Some people (1 in 10,000) cannot metabolise
phenylalanine (phenylketonuria) gives high
levels of neurotransmitters, headaches
Use 10 Mkg/yr in NA, 80 of NA market (70 of
use in soft drinks) Not so useful in cooked
goods 100s of web sites with information! BEWAR
E SOURCES!!! Can Chem News June 06 Not
carcinogenic Nat Canc Inst (US) study
17
NEOTAME (made by NutraSweet, 2002) 104 x sweeter
than sugar
HEAT STABLE useful in baking http//www.cfsan.f
da.gov/lrd/tpneotam.html
ACESULFAME-K (1967) 200 x sweeter than sugar
(sold as Sunett)
Used in drugs, toothpaste, mouthwashes... approved
for foods, HEAT STABLE popular in Europe for
decades but only approved for general use in US
in 2003 http//www.caloriecontrol.org/acesulf.htm
l
18
SUCRALOSE 600 x sweeter than sugar Can
(91) FDA (98) WHO (91)
Chlorinated galacto-sucrose i.e. Gal-Fru More
than 100 studies indicate no adverse affects at
very high and prolonged dosages Can. Diabetes
Assoc. guidelines 1.65 g/d for life (for someone
of my weight) with no adverse effects ( 1 kg
sugar/d) Fat insoluble so does not
bio-accumulate but may accumulate in the
environment
19
COLORS FDC (Food, drugs and cosmetics
approved) Purely cosmetic, slowly being reduced
in number 30 left, ½ natural, ½ synthetic
They are all highly conjugated so that they
absorb visible light in 400-700 nm region we
see the complimentary color eg. b-carotene
absorbs blue-violet so we see orange-red
20
Older coal tar dyes now synthesised with water
solubilizing groups SO3-, COO- or OH so that dye
is excreted without metabolizing Most of older
fat soluble dyes have been eliminated
(carcinogenic) egs. butter yellow, yellows 34,
orange 1, reds 24, violet 1 Sudan Red G (an
example of an azo dye) caused a large food
recall in UK in 2005 No longer used -
carcinogenic Cochineal (Carminic acid) comes
from dried pregnant scale insects of Mexico, Peru
and the Canary Islands highly valued dye
in colonial Mexico farmed in Australia
21
ADDITIVES TO CONTROL ACIDITY Fruit acids
citric, tartaric, malic and lactic acid are used
in fruit drinks Phosphoric acid (H3PO4) is used
in cola type drinks
malic acid tartaric acid citric acid
lactic acid (apples) (grapes)
(lemons) (milk) In candy manufacture,
acid converts sucrose to softer invert sugar LOW
ACID gives hard (crystalline) candies HIGH ACID
gives softer, chewy (less crystalline) candies
22
BUFFERS usually sodium or potassium salts of di
or tri-acids eg. potassium acid tartrate
ANTI-CAKING AGENTS prevent moisture from forming
lumps 1 magnesium silicate in salt sodium
aluminosilicate in non-dairy creamer silicon
dioxide (silica) in soups (same stuff in those
little bags that come with electronic equipment
etc.)
About PowerShow.com