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Several types of dyes are available in the market as colouring agents to food commodities. Some commonly used synthetic food dyes include: brilliant blue, indigo carmine, citrus red, fast green, erythrosine, allura red, tartrazine and sunset yellow. The main food biocolorants are carotenoids, flavanoids, anthocyanidins, chlorophyll, betalain and crocin. There has been a rising concern over the health implications of the use of food dyes in human diets. How safe are these food colourants? This has led to a lot of studies, both by individual researchers, corporate organization-sponsored and even government-sponsored researches, to authenticate the benefits or risks associated with the use of food colourants (synthetic and natural). This review critically evaluated scientific researches from various published journal articles and reports, with a view of clarifying the health implications of using these food dyes. Various studies have shown that synthetic food colourants have considerable toxicological effects, including but not limited to carcinogenicity, hypersensitivity reactions, and behavioral effects. However, natural food colourants have been found to be relatively safe to humans. Besides the colouring property, they have been found to possess a number of pharmacological properties like strong antioxidant, antimutagenic, anti-inflammatory, antineoplastic and antiartheritic effects.
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UK Journal of Pharmaceutical and Biosciences Vol. 4(4), 01-11, 2016 REVIEW ARTICLE
Assessment of the Health implications of Synthetic and Natural Food Colourants
A Critical Review
Sunday N. Okafor1*, Wilfred Obonga1, Mercy A. Ezeokonkwo2, Jamiu Nurudeen3, Ufoma Orovwigho3,
Joshua Ahiabuike
1Department of Pharmaceutical and Medicinal Chemistry, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria
2Department of Pure and Industrial Chemistry, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria
3Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka 410001, Enugu State, Nigeria
Article Information
Received 15 March 2016
Received in revised form 25 June 2016
Accepted 29 June 2016
Several types of dyes are available in the market as colouring agents to food commodities.
Some commonly used synthetic food dyes include: brilliant blue, indigo carmine, citrus red,
fast green, erythrosine, allura red, tartrazine and sunset yellow. The main food biocolorants
are carotenoids, flavanoids, anthocyanidins, chlorophyll, betalain and crocin. There has been
a rising concern over the health implications of the use of food dyes in human diets. How
safe are these food colourants? This has led to a lot of studies, both by individual
researchers, corporate organization-sponsored and even government-sponsored researches,
to authenticate the benefits or risks associated with the use of food colourants (synthetic and
natural). This review critically evaluated scientific researches from various published journal
articles and reports, with a view of clarifying the health implications of using these food dyes.
Various studies have shown that synthetic food colourants have considerable toxicological
effects, including but not limited to carcinogenicity, hypersensitivity reactions, and behavioral
effects. However, natural food colourants have been found to be relatively safe to humans.
Besides the colouring property, they have been found to possess a number of
pharmacological properties like strong antioxidant, antimutagenic, anti-inflammatory,
antineoplastic and antiartheritic effects.
Food colourants,
Synthetic, natural,
Health benefits,
Toxicological effects
Corresponding Author:
E-mail :
Mob.: +2348036556699
1 Introduction
The natural and synthetic color additives were used extensively
to color foods, drugs and cosmetics1. This was largely due to
their cost effectiveness and tinctorial power2. Food
Manufacturers have used food colourants as a means of
ascertaining the level of acceptability of processed food by
consumers 3,4. The flavor perception of a food or beverage has
been shown to have a direct correlation to its colour5. Therefore,
it has appeared fashionable to use them in various food
Possible reasons for use of colorants in food substances are
enumerated (FNB, 1971):
To maintain the original food appearance even after
processing and during storage;
To assure the color uniformity for avoiding seasonal
variations in color tone;
To intensify normal color of food and thus to maintain its
To protect the flavor and light susceptible vitamins making
a light-screen support; and
To increase acceptability of food as an appetizing item6.
The demand for food color in global market in 2000 was 2400
Metric Tons (MT) which increased to 3000 MT by the year 2005
and further to increase to 8000 MT by the year 2010 and is
UK Journal of Pharmaceutical and Biosciences
Available at
ISSN: 2347-9442
Okafor et al., Assessment of the Health implications of Synthetic and Natural Food Colourants
UK J Pharm & Biosci, 2016: 4(4); 2
expected to increase to 15000 MT by the year 20157. Also,
Revanker and S. S. Lele, (2007) reported that because of the
wide applications of these clourants, the total world colorant
production is estimated to be 8,000,000 tons per year8.
There are varieties of colours. Because of the ability of these
food colours to influence or stimulate appetite and make it
appeal to consumers more strongly thereby influencing their
judgement, food manufacturing companies have explore this as
a major strategy in food marketing. Food colors can be grouped
divided into four categories: a) natural colors, b) nature-identical
colors, c) synthetic colors and d) inorganic colors5,9.
There is an increasing worries over the safety of the synthetic
food colourants. In 1820, English chemist Friedrich Accum was
the first to bring this growing problem to the public’s attention
with his publication of A Treatise on Adulterations of Food and
Culinary Poisons10. The book lists countless examples of
contemporary foods that either using poisonous dyes or any
colorant that masked the true nature of the product.
In the past few years, people are becoming increasingly aware
of the use of natural colorants11. Many of the approved artificial
dyes are being delisted because of consumer preference as
well as legislative action12. Consequently, there is a growing
demand of natural food colours as against the synthetic colours.
About US $ 1 billion has been invested to increase the supply of
these natural food colours6.
2 Chemistry of coloured compounds
Dyes are organic compounds with characteristic colours. The
compounds owe these characteristic colours due to their ability
1. absorb light in the visible spectrum (400700 nm),
2. have at least one chromophore (colour-bearing group),
3. have a conjugated system, i.e. a structure with alternating
double and single bonds, and
4. exhibit resonance of electrons, which is a stabilizing force
in organic compounds.
The compound (dye) loses its colour when any of these features
is lacking from the molecular structure. Some of these dyes can
also contain colour helpers group(s) called auxochromes. Their
role is to shift the colour of thedye and influence their solubility.
Examples of such group include hydroxyl, carboxylic acid,
sulfonic acid and amino groups. Table 1 show the relationships
between wavelength of visible and colour absorbed/observed
(Table 1). Tables 2 and 3 show examples of natural and
synthetic food dyes containing chromophoric groups.
3 Health implications of synthetic food colourants
Sahar and Manal (2012)14 conducted a research to investigate
the effect of using colour foods [(Colour fruit juice for 6 - 12 hr)
on the serum biochemical, and on the liver and kidney of rats for
13 weeks. Tomato ketchup potato chips, TKPC (30%) showed a
significant increase in total cholesterol (TC) and triacyl- glycerol
(TG). The level of ALT and AST was significant increase of rat’s
administration color fruit juice (for 12 hr) and TKPC at 30%.
Table 1: Wavelength of light absorption versus colour in
organic dyes
Absorbed (nm)
There was also a significant increase in serum creatinine and
albumen. Both low and high colour foods consumed exhibited
significant decrease in liver GSH. The study also revealed that
high concentration of colour foods lead to increased number of
WBC as the result to the response of the immune system to the
inflammation. Their findings showed that color fruit juice
containing sunset yellow, tartazine and carmosine lead to
significant increase in ALT of serum rats. Therefore, they
concluded that the synthetic colours used in their research have
adverse effects on some of the serum biochemical, liver and
These results were well supported by the data reported by
Mekkawy et al.15, and Amin et al.16, who indicated that rats
which consumed high dose synthetic color (Tartarzine,
Carmoisin, sunset yellow and fast green) showed a significant
increase in serum ALT and AST when compared to control rats.
A significant increase in serum ALT and AST may attribute
those changes in liver function to be hepatocellular impairment
level of intracellular enzymes into the blood17. This was more
evident in the histopathological studies. At low dose synthetic
color, the liver revealed a disruption of hepatic cells near the
central vein and hepatocellular damage. These results are in
agreement with the Sharma et al.18 who reported that synthetic
colours have adverse effect on vital organs. The release of a
normally high level of specific tissue enzymes into blood stream
is dependent on both the degree and type of damage exerted
by the toxic compound administration19,20. Furthermore, there
Okafor et al., Assessment of the Health implications of Synthetic and Natural Food Colourants
UK J Pharm & Biosci, 2016: 4(4); 3
was a significant increase in the serum creatinine. It is believed
that the significant elevation in creatinine level is closely related
to the impairment of renal function.
Table 2: Examples of Natural food dyes containing chromophoric groups
Pelargonidin (R1,
OH, R2=H)
E 163
Beta Carotene
E 160a
E 160d
E 161b
Okafor et al., Assessment of the Health implications of Synthetic and Natural Food Colourants
UK J Pharm & Biosci, 2016: 4(4); 4
E 100
E 140
Table 3: Some examples of Synthesis Food Colourants
Brilliant Blue
Blue #1
Blue #2
Red #2
Fast Green
Green #3
Red #3
Allura Red
Red #40
Okafor et al., Assessment of the Health implications of Synthetic and Natural Food Colourants
UK J Pharm & Biosci, 2016: 4(4); 5
Yellow #5
Sunset Yellow
Yellow #6
The present findings are in accordance with data reported by
Ashour and Adelaziz21, who observed a significant elevation in
serum creatinine and urea level of rats doses with azo dye (fast
green) orally for 35 days. The group administrated with
chocolate and sweet colored at low and high concentrations
witnessed a significant increase in triglycerides. These results
again are in accordance with the results obtained by Abou El-
Zahab et al.22, and Himiri et al.23, who observed significant
increase in serum triglycerides of rats treated with synthetic
color (tartrazine) and chocolate color A and B that containing
tartrazine and Carmoisne.
The cytotoxicity of 11 dyes, used as food dyes in Japan, on
cultured fetal rat hepatocytes was studied24. Xanthene dyes
containing halogen atoms in their molecules such as phloxin,
rose bengal, and erythrosine were more toxic than other groups
of food dyes. The effect of food dyes on the cell growth of
hepatocytes was also examined. The high hepatotoxicity of
phloxin to the cell growth, which was dose-dependent, was
observed when the dye was added 3 days after plating.
A double blind placebo controlled high dose azo dye challenge
in a highly selected group of children with behaviour disturbance
suggested a small adverse effect on the children’s behaviour
based on ratings on the Connor scale25. Bateman et al (2004)
carried out a work on the effects of artificial food colourings and
benzoate preservative challenge on hyperactivity in a general
population sample of preschool children26. They found out that
there is a general adverse effect of artificial food colouring and
benzoate preservatives on the behaviour of 3 year old children.
They concluded that children would benefit more if artificial food
colours and benzoate preservatives were removed from their
The studies carried out by the Center for Science in the Public
Interest (CSPI), on food dyes revealed that27, some of the most
commonly used food dyes may be linked to numerous forms of
cancer. CSPI reported:
"The three most widely used dyes, Red 40, Yellow 5, and
Yellow 6, are contaminated with known carcinogens Another
dye, Red 3, has been acknowledged for years by the Food and
Drug Administration to be a carcinogen, yet is still in the food
In their 58-page report, ―Food Dyes: A Rainbow of Risks‖ CSPI
revealed that nine of the food dyes currently approved for use in
the United States are linked to health issues ranging from
cancer and hyperactivity to allergy-like reactions, and these
results were from studies conducted by the chemical industry
itself. For instance,
Red # 40, which is the most widely used dye, may
accelerate the appearance of immune system tumors in
mice, while also triggering hyperactivity in children.
Blue # 2, used in candies, beverages, pet foods and more,
was linked to brain tumors.
Yellow 5, used in baked goods, candies, cereal and more,
may not only be contaminated with several cancer-causing
chemicals, but it's also linked to hyperactivity,
hypersensitivity and other behavioral effects in children.
As CSPI reported28
"Almost all the toxicological studies on dyes were
commissioned, conducted, and analyzed by the chemical
industry and academic consultants. Ideally, dyes (and other
regulated chemicals) would be tested by independent
researchers. Furthermore, virtually all the studies tested
individual dyes, whereas many foods and diets contain mixtures
of dyes (and other ingredients) that might lead to additive or
synergistic effects. In addition to considerations of organ
damage, cancer, birth defects, and allergic reactions, mixtures
Okafor et al., Assessment of the Health implications of Synthetic and Natural Food Colourants
UK J Pharm & Biosci, 2016: 4(4); 6
of dyes (and Yellow 5 tested alone) cause hyperactivity and
other behavioral problems in some children.
In a placebo-controlled study conducted in 2007 and published
in The Lancet journal29, the work critically evaluated the effects
of common food dyes found in many soft drinks, fruit juices and
salad dressings. The results showed that dyes studied caused
some children to be more hyperactive and distractible. As a
support to the findings in the Lancet, a research work reported
in the Annals of Allergy30 revealed that 73 percent children who
were suffering from ADHD responded favourably to a diet which
artificial colours have been removed. The Lancet study found
that E-numbered food dyes cause as much damage to the
children’s brains as lead in gasoline, leading to significant
reduction in their IQ. At the wake of these findings, the British
Food Standards Agency (FSA) issued advisory warning to
parents to limit their children’s intake of food additives. FSA also
advised the food industry to voluntarily remove the six food dyes
named in the study back in 2009, and replace them with natural
alternatives if possible. UK food dyes on which the Food
Standards Agency has called for a voluntary ban include:
Tartrazine, Quinoline Yellow, Sunset Yellow, Carmoisine,
Ponceau 4R, and Allura Red31.
According to the Washington Post32
“Beyond the behavioral problems and cancer risks, the greatest
hazard that dyes pose for children may also be the most
obvious: They draw kids away from nutritious foods and toward
brightly colored processed products that are high in calories but
low in nutrients, such as fruit-flavored drinks and snack foods.
Those types of foods are a major force in America’s obesity
4.2 Health benefits of natural food colourants
Natural food colourants (biocolorants) may also play an
important role in human health as they contain some biologically
active compounds, which possess a number of pharmacological
properties like strong antioxidant, antimutagenic, anti-
inflammatory and antiartheritic effects33-41. Carotenoids are also
used as vitamin supplements42, since β-carotene is the
precursor of vitamin A. The regular intake of carotene can help
prevent night blindness resulting from inadequate supply of
vitamin A. Carotenoids also act as biological antioxidants,
protecting cells and tissues from the damaging effects of free
radicals and singlet oxygen and also as a good source of anti-
tumor agent43.
Lycopene, is particularly effective at quenching the destructive
potential of singlet oxygen44. Lutein, zeaxanthin and
xanthophylls are believed to function as protective antioxidants
in the macular region of the human retina45-47. These
compounds also act against aging, mascular degeneration, and
senile cataracts48. Canthaxanthin also shows antioxidant
property49. Astaxanthin is another naturally occurring
xanthophyll with potent antioxidant properties44.
Food phenolic compounds, particularly flavonoids, are thought
to play important roles in human health50-52. A number of
studies, both in vivo and in vitro studies have demonstrated that
flavonoids have antioxidant and antimutagenic activities53 and
could be very useful in the reduction of the risk of developing
cardiovascular disease and stroke54. Flavonoids may act as
antioxidants to inhibit free-radical mediated cytotoxicity and lipid
peroxidation, as antiproliferative agents to inhibit tumor, growth
or as weak estrogen agonists or antagonists to modulate
endogenous hormone activity55. Flavonoids have been labeled
as ―high level‖ natural antioxidants on the basis of their abilities
to scavenge free radicals and active oxygen species56-58 as
result of the hydroxyl groups and the conjugated ring system
through halogenation or complexing with these oxidizing
species59,60. In these ways, flavonoids may confer protection
against chronic diseases such as atherosclerosis and cancer
and assist in the management of menopausal symptoms. Thus,
flavonoids have been referred to as semi-essential food
Consumption of quercetin may protect against cardiovascular
disease62 by reducing capillary fragility and inhibiting platelet
aggregation63. Several flavonoids such as catechin, apigenin,
quercetin, naringenin, rutin, and venoruton are reported for their
hapatoprotective activities64. Anthocyanins have drawn
increasing attention because of their preventive effect against
various diseases. Zhu et al.65 demonstrated that anthocyanin
cyanidin-3-O-β-glucoside (C3G) increases hepatic Gclc
expression by increasing cAMP levels to activate protein kinase
A (PKA), which in turn upregulates cAMP response element
binding protein (CREB) phosphorylation to promote CREB-DNA
binding and increase Gclc transcription. Increased Gclc
expression results in a decrease in hepatic ROS levels and
proapoptotic signaling. It was also shown that the C3G
treatment reduces hepatic lipid peroxidation, inhibits the release
of proinflammatory cytokines, and protects against the
development of hepatic steatosis65.
Other health benefits of biocolorants include enhancement of
immune system function66, protection from sunburn67, and
inhibition of the development of certain types of cancers68.
Lycopene prevents oxidation of low-density lipoprotein (LDL)
cholesterol and reduces the risk of developing atherosclerosis
and coronary heart disease69. Epidemiological studies have
revealed a correlation between the consumption of chlorophylls
and decreased risk of colon cancer70. They have also been
observed to possess antineoplastic, radiation-protective,
vasotonic, vasoprotective, anti-inflammtory and
hepatoprotective activities71. A flavaoured and brightly coloured
seed of Manikara obovate has been showed to have both
antioxidant and hepatoprotective activities72.
Table 4: Colour additives to avoid
Status worldwide:
Where found
Possible negative effects:
FD&C Red
No. 3
Banned for use in cosmetics and
external drug, but not food and
ingested drugs in
the U.S.
canned fruits
dairy products
snack foods.
Yellow No. 5,
Banned in Norway and Austria.
Ice cream
Carbonated drinks
Fish sticks
Hyperactivity, asthma, skin
rashes, and migraine
Banned in Australia, Japan,
Norway and the U.S.
Restricted to max.
Permitted levels in U.K.
Soft drinks
Ice creams
Asthma, rashes and
hyperactivity. Potential
carcinogen in animals:
implicated in bladder and liver
cancer. Altered reproduction
in animals.
Yellow FCF
Yellow S
Banned in Norway, Sweden and
Finland. Restricted to
maximum permitted levels in U.K.
Snack foods
AVOID in allergies & asthma.
Cancer DNA damage,
increases tumors in animals.
Growth retardation and
severe weight loss in
Banned in Canada, Japan, Norway,
Austria, Sweden
and the U.S. Restricted to
maximum permitted levels in U.K.
DNA damage and
tumours in animals.
Allura red
FD&C Red
No. 3
Banned in Denmark,
Belgium, France, Germany,
Switzerland, Sweden,
Austria and Norway
Carbonated drinks
Bubble gum, snacks,
Sauces, preserves,
Soups, wine, cider,
May worsen or induce
asthma, rhinitis (including
hayfever), or urticarial (hives).
Ponceau 4R
Banned in US, Canada, Norway,
Sweden and Japan. Restricted to
maximum permitted levels in the
Carbonated drinks
Cancer - DNA damage and
tumours in animals. Can
produce bad reactions in
Banned in the U.S.
Alcoholic drinks
Fish roe
May worsen or induce
asthma, allergies or hives.
Okafor et al., Assessment of the Health implications of Synthetic and Natural Food Colourants
UK J Pharm & Biosci, 2016: 4(4); 8
Banned in the US, Japan, Australia
and Norway. UK use restricted to
maximum permitted levels
Baked goods
Confectionery items
May cause nausea,
vomiting, skin rashes, and
brain tumors. DNA
damage and tumors in
Banned in Austria, Belgium,
France, Norway, Sweden,
Switzerland and Germany.
Restricted to maximum
permitted levels in U.K.
Dairy products
Hyperactivity and skin
rashes. Listed as human
carcinogen by the US EPA.
Causes DNA damage and
tumors in animals
*All of these additives are considered the ―Dirty Dozen Food Additives‖ and are prohibited in the UK for foods marketed for children less than 36 months.
5 Recommendations
1. People should try to stick to unprocessed naturally
colored foods for their health
2. The food industry should voluntarily remove harmful
food dyes and replace them with natural alternatives if
3. Foods that contain artificial food dyes should be
labeled with warning labels stating the food "may
have an adverse effect on activity and attention in
4. Relevant Government agencies should issue an
immediate advisory to parents, warning them to
limit/avoid their children's intake of additives if they
notice an effect on behavior
5. Food and Drug regulatory agencies should ban food
dyes, which serve no purpose other than a cosmetic
6. Some laws making it difficult to ban certain food
colourants should be amended to make it no more
difficult to ban food colorings than other food
6 Conclusions
As a result of carcinogenicity, hypersensitivity reactions, and
behavioral effects and other toxicological considerations, food
dyes cannot be considered safe. We strongly advocate that
food and drug regulatory agencies of various countries should
rise up and ban food dyes, which serve no purpose other than a
cosmetic effect, borrowing a leave from Japan and all European
countries have banned trading of synthetic color made products.
In the meantime, food companies should voluntarily replace
dyes with safer, natural colorings, which has been found to be
relatively safe and with health benefits.
7 Acknowledgements
The Authors wish to acknowledge the supports from
Ogechukwu Ugwu, Uchechi Uchenyi, Gloria Eze, Ifudu Unoaku
and Glory James. We also wish to thank Young Researchers’
Forum of Nigeria for their encouragement and supports
throughout the period of this work.
8 Conflict of interest
We declare that there is no conflict of interest
9 Author’s contributions
SNO, JN, UU and JA contributed to the design, collection of
data, carried out literature review; SNO prepared the
manuscript; WO and MAE supervised the entire work. All
authors read and approved the final manuscript.
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... Food colorants are one of the most commonly used additives in the food industry. While the major function of food colorants is to enhance the aesthetic appeal of a food item or product, sub-functions may include maintaining the original food appearance post-processing and during storage, assuring color uniformity, maintaining or improving safety and freshness, protecting flavor while also acting as a lightscreen support, improving the appearance and intensifying the inherent color of food, thereby elevating the overall quality and acceptability of a food product (Bora et al., 2019;Okafor et al., 2016). In fact, color is an integral marketing tool used by food industries; foods that are available in different colors have greater sales as each color has a different psychological impact on consumers (Connolly, 2018). ...
... Although the permitted synthetic food colorants are quite safe to use, their prolonged usage may still pose serious health defects in the long run. Numerous studies have linked artificial or synthetic food colorants with increasing rates of hyperactivity (especially in children), allergic reactions, skin irritation, behavioral changes like irritability and depression, and tumor growth and increasing rates of chronic diseases, among others (European Food Safety Authority, 2008;Okafor et al., 2016;Bora et al., 2019). Nonetheless, food colorants are still extensively used in the food industry since the palatability of food products largely depends on color. ...
... Synthetic food colorants have been reported to induce healthrelated adverse effects on consumers. These possible health effects include hyperactivity, asthma, skin rashes, headaches, migraine, behavioral problems, and cancer (Bora et al., 2019;Okafor et al., 2016); these effects are substantiated by numerous studies. For instance, the findings of the infamous "Southampton Six" study interpreted that artificial color in food products led to increased hyperactivity among 3-year-old and 8/9-year-old children of the general population (European Food Safety Authority, 2008). ...
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The current trend of shifting to food naturalness has prompted food industries to switch from synthetic to natural colorants. Concurrently, there is a spike in interest concerning the extraction of pigments from natural sources using non-conventional extraction techniques as the latter are environmental-friendly and sustainable compared to traditional methods. Microwave-assisted extraction (MAE) is one of the emerging technologies that has been reported to be effective in the recovery of bioactive compounds from a plethora of natural sources because of its ability to expeditiously heat the extraction matrix, leading to rapid product recovery. This review focuses on the voluminous demand for natural colorants, their limitations, and potential food applications. Also, this review emphasizes the underlying principle and mechanism of MAE, as well as studies that unveil the efficacy and suitability of the technique for the recovery of pigments. Hence, given that natural pigments are susceptible to natural degradation, MAE is a promising technology for enhanced pigment yield and stability. In addition, recent trends such as technology integration and novel extraction solvents have considerably widened the scope and versatility of MAE as a greener extraction method. Furthermore, when coupled with MAE, waste valorization and further exploration of novel pigment sources (such as algae and other microorganisms) present thrust areas of research concerning the global sustainable development goals (SDGs).
... Thus, food manufacturing corporations looked into this as a crucial marketing tactic. Inorganic colors, synthetic colors, nature-identical colors, and natural colors are the four categories into which food colors fall [3]. Sir William Henry Perkin created mauvine in 1856, the first artificial color. ...
... Natural food colorants can have a significant impact on human health due to their range of therapeutic qualities, including antioxidant, anti-inflammatory, antimutagenic, and anti-rheumatic effects. Due to this biological activity, the use of food colorants has expanded in the food industry [3]. The majority of natural dyes are currently imported into the United States of America, but according to a report by the German Ministry of Food, agriculture, and Forestry, 900 tonnes of natural colors can be produced in a year. ...
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The most crucial component of every food product is its color, which increases its acceptability and attractiveness. Synthetic colorants have gradually been replaced with natural-derived alternatives as a result of consumer perception and demand. Natural colors have a variety of health benefits, including antioxidant, anti-cancer, and anti-inflammatory properties. Natural colorants come from a variety of sources, including plants, microbes, animals/insects, and minerals. Many plants contain pigments, which are responsible for their natural hues. Chlorophyll (green), carotenoids (orange, yellow), anthocyanins (red, blue, purple), and flavonoids are among these pigments (red, blue, purple). Natural pigments give animals and insects their hues as well. Carotenoids are found in the feathers, scales, and fur of many birds, fish, and reptiles. Microorganisms that create pigments, such as bacteria and fungus, are also responsible for their natural hues. Carotenoids are pigments found in orange, yellow, and red that are generated by a variety of microorganisms, including bacteria and algae. Certain species of algae and cyanobacteria create phycobiliproteins, which come in red, blue, and purple hues. Certain microbes also create pigments such as riboflavin, flavins, and niacin, which provide yellow, orange, and red colors, respectively. These pigments can be used to impart natural colour to fermentation operations such as yoghurt and cheese manufacture. This review aims to outline the sources of natural colorants and their uses in the food industry, such as dietary supplements, food preservatives, and medicines with quality-controlling capabilities.
... Nowadays, all the countries worldwide are focusing on use of food additive and colorant-related regulations [106]. The food and medicine administrations of many nations are urged to act and outlaw the use of artificial colours in foods [107]. In addition, we currently know very little about what happens to the wastes produced by the factories that make food colouring agents in the environment. ...
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Colour is an important factor to enhance the consumer acceptance and appetizing value towards food and beverages. Foods are coloured with both natural and artificial/ synthetic food dyes. Instead of natural food colours, synthetic food colours are now widely employed by the food industry because of its superior features (cheap cost, enhanced look, greater colour intensity, increased colour stability, and consistency). Life of synthetic colorants is quite long as they are highly soluble in water and oil. Based on their solubility, synthetic colorants are classified into fat soluble synthetic colours, lake colours, water soluble synthetic colours. Colouring agents have spread across the water and soil ecosystem, this is because they are mass-produced and wider application. Samples of water, suspended particles, sediment, and wild fish have all tested positive for food dyes. As a result, they are regarded as micropollutants in aquatic systems. Cancers, mutations, neurotoxic effects, decreased haemoglobin concentrations, allergic reactions, food hypersensitivity, abdominal pain, worsened asthmatic symptoms, vomiting, and diarrhoea are just some of the potential dangers to one's health, which can result from using synthetic colours that aren't allowed or using them in excess. This review critically evaluates the effect of synthetic food colouring agents on aquatic environment and human health. We found that there is a definite unfavourable effect of synthetic organic additives on aquatic life and human health. Some synthetic colouring dyes have toxicological qualities and pharmacological action, thus it's important to keep an eye on water bodies. Synthetic organic food colour in water ecosystems may constitute a harmful effect on animals or human health’s, it is urgent need to evaluate the hazard potential of these substances. For this reason, it is strongly suggested that both consumers and manufacturers of food colours should be aware about the rules and regulations regarding food colours. GRAPHIC ABSTRACT
... These natural pigments can also be derived from fruits and vegetable wastes and by-products, such as seeds, peels, skins, and leaves [9]. These natural pigments contain a variety of bioactive compounds with physiological effects, such as antioxidants and antimicrobials, and can protect tissues and cells from free radicals and singlet oxygen damage; they can also extend the shelf life of fresh or processed food [10,45,46]. Table 1 exhibits the synthetic and natural active compounds that are currently being used as additives for intelligent food packaging indicators. ...
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Food safety and security are top priorities for consumers and the food industry alike. Despite strict standards and criteria for food production processes, the potential for food-borne diseases due to improper handling and processing is always present. This has led to an urgent need for solutions that can ensure the safety of packaged foods. Therefore, this paper reviews intelligent packaging, which employs non-toxic and environmentally friendly packaging with superior bioactive materials that has emerged as a promising solution. This review was prepared based on several online libraries and databases from 2008 to 2022. By incorporating halal bioactive materials into the packaging system, it becomes possible to interact with the contents and surrounding environment of halal food products, helping preserve them for longer periods. One particularly promising avenue of research is the use of natural colourants as halal bioactive materials. These colourants possess excellent chemical, thermal, and physical stabilities, along with antioxidant and antimicrobial properties, making them ideal candidates for use in intelligent indicators that can detect food blemishes and prevent pathogenic spoilage. However, despite the potential of this technology, further research and development are needed to promote commercial applications and market development. With continued efforts to explore the full potential of natural colourants as halal bioactive materials, we can meet the increasing demand for food safety and security, helping to ensure that consumers have access to high-quality, safe, and nutritious foods.
... They have been widely used in various processed foods as food additives and have an integral position in the market [3] . However, most synthetic pigments are unhealthy, which may cause certain allergy, diarrhea, carcinogenicity, mutagenicity [4,5] and attention deficit hyperactivity disorder (ADHD) in children [6] . Therefore, some synthetic food pigments, such as E128, E156, had been banned. ...
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In recent years, natural pigments have been widely used in meat products (pork/beef patties, sausages, etc.) to maintain color, and as an antioxidant and antibacterial to extend the shelf life of meat products. To date, the food pigment industry has developed rapidly. Natural pigments are more popular among consumers because of their color and physiological functions such as bacteriostatic and antioxidant activity. However, compared with synthetic pigments, some natural pigments have poor stability and water solubility, which limit their application in the food industry. Therefore, taking certain methods to improve their stability and water solubility can expand the scope of use of the pigments and achieve favourable economic benefits. In this paper, we briefly analyze the main factors affecting the stability of natural pigments and summarize the methods commonly used to improve them. The methods mainly include the use of antioxidants and encapsulation of the pigments through spray/freeze drying, complex coacervation, ionic gelation, supercritical anti-solvent, etc. Finally, this paper also outlines the use of stabilized and non-stabilized pigments in meat products so as to serve as a baseline for use in meat and meat products.
... 23.5 µg/g of dry substrate [103] (Continued) [40]. Microorganisms are among the potential natural resources for production of natural colourants (microbial pigments) with anti-cancer and antioxidative properties. ...
Fruits and vegetables are among the most widely consumed horticultural commodities. With the increasing prevalence of lifestyle diseases, consumers have become more health conscious and consumption of fruits and vegetables has increased significantly. This has led to an increase in the processing of these commodities in order to enhance their shelf-life and to ease their export/import worldwide. The significant quantity of waste from the processing industry, as well as the losses in the supply chain of fresh farm produce, often leads to environmental and economical problems. The high organic content in such waste contributes to water and soil pollution. This chapter addresses the developments in microbial processing technologies for valorization of fruits and vegetables waste. Fermented beverages, enzymes, single-cell proteins, flavors, biopesticides, plant growth regulators, and biofuels are the key bioproducts discussed. Technical challenges associated with scale-up of microbial fermentation technologies have been identified and specific solutions have been proposed.
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Several medicinal plants are currently used to detoxify the liver and to protect the hepatocytes from effects of poison including drugs and chemicals. Certain drugs and chemicals have contributed to the degeneration and inflammatory diseases of the liver. Manikara obvata seeds are among the vast of natural remedies for liver degeneration. Therefore, the present study evaluated the antioxidant and hepatoprotective activities of methanolic and petrolueum ether extracts of Manikara obovata seed against carbon tetrachloride (CCl4)-induced hepatic damage in rats. Thesubstantially elevated serum enzymatic levels of serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), serum alkaline phosphatase (ALP) and acid phosphatase (ACP) were restored towards normalization by the extracts when compared with the CCl4-intoxicated control rats. The extracts also protected against CCl4 induced lipid peroxidation. The acute toxicity, LD50, was also determined to be greater than 5000mg/kg. The results showed that the extracts from the seed of Manikara obovata posses significant antioxidant and hepatoprotective activities.
The role of natural and synthetic colors in foods and beverages regulated in United States is described. Refrigeration, canning, dehydration, smoking, bottling and exposure to light, air, moisture and temperature extremes tend to alter the natural color. Synthetic certified colors are the most popular type of food colorings as they are brighter, more uniform, better characterized and of higher tinctorial strength, encompass a wider range of hues and are less expensive than colors derived from nature. Natural colors are used in the fast-growing functional, natural, organic and vegetarian markets, even though they are often synthetically derived, extracted or preserved.
This book serves as a comprehensive overview of the current scientific knowledge on the health effects of dietary and supplemental antioxidants (such as vitamins C and E). Chapters integrate information from basic research and animal studies, epidemiologic studies, and clinical intervention trials. The popular media has taken great interest in antioxidants, with numerous articles emphasizing their role in preventing disease and the possible slowing of the aging process. These antioxidant vitamins may be important in preventing not only acute deficiency symptoms, but also chronic disorders such as heart disease and certain types of cancer. This book, therefore, is not only for scientists and doctors, but also for health writers, journalists, and informed lay people. The text focuses on several human conditions for which there is now good scientific evidence that oxidation is an important etiological component. Specifically, antioxidants may prevent or slow down the progression of: Cancer, Cardiovascular disease, Immune system disorders, Cataracts, Neurological disorders, Degeneration due to the aging process.
This research investigates the role that food color plays in conferring identity, meaning and liking to those foods and beverages that assume many flavor varieties. In a taste test experiment manipulating food color and label information, 389 undergraduates at a public university (53% male and 47% female; 79% between 18 and 21 years of age) were assigned the task of evaluating a successful brand of powdered fruit drink. Results from this study indicate that food color affects the consumer’s ability to correctly identify flavor, to form distinct flavor profiles and preferences, and dominates other flavor information sources, including labeling and taste. Strategic alternatives for the effective deployment of food color for promotional purposes at the point of purchase are recommended.
Various natural carotenoids have been proven to have anticarcinogenic activity. Epidemiological investigations have shown that cancer risk is inversely related to the consumption of green and yellow vegetables and fruits. As β-carotene is present in abundance in these vegetables and fruits, it has been investigated extensively as a possible cancer preventive agent. However, various carotenoids which coexist with β-carotene in vegetables and fruits also have anticarcinogenic activity, and some of these, such as α-carotene, lutein and lycopene, show a higher potency than β-carotene in suppressing experimental carcinogenesis. Thus, we have carried out more extensive studies on cancer preventive activities of natural carotenoids in foods. For example, we found that β-cryptoxanthin showed antitumor initiating activity, as well as antitumor promoting activity. It is of interest that not only carotenoids distributed in vegetables and fruits, but also animal carotenoids, such as astaxanthin, are promising as cancer preventive agents. In the present study, the cancer preventive potential of phytoene was also confirmed. The establishment of NIH3T3 cells that produce phytoene by introducing the crtB gene provides evidence that resistance against transformation, imposed by transfection of activated H-ras oncogene, was acquired by phytoene production. Analysis of the action mechanism of these natural carotenoids is now in progress, and some interesting results have already been obtained; for example, various carotenoids were suggested to stimulate the expression of RB gene, an antioncogene.