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Frying Process: From Conventional to Air Frying
Aline Nalon Zaghi, Sandra Maria Barbalho, Elen Landgraf Guiguer & Alda
To cite this article: Aline Nalon Zaghi, Sandra Maria Barbalho, Elen Landgraf Guiguer & Alda
Maria Otoboni (2019) Frying Process: From Conventional to Air Frying Technology, Food Reviews
International, 35:8, 763-777, DOI: 10.1080/87559129.2019.1600541
To link to this article: https://doi.org/10.1080/87559129.2019.1600541
Published online: 02 Apr 2019.
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Frying Process: From Conventional to Air Frying Technology
Aline Nalon Zaghi
, Sandra Maria Barbalho
, Elen Landgraf Guiguer
and Alda Maria Otoboni
Department of Food Technology, Food Technology School, São Paulo, Brazil;
Medical School of Marília,
UNIMAR, São Paulo, Brazil
Studies have shown that products resulting from oils heated for long
periods under high temperatures contain polar compounds such as
polymers, dimers, free fatty acids, and acrylamide, which lead to
metabolic changes, malabsorption of essential fat, and development
of cancer. The air frying process is capable of reaching the character-
istic color and similar ﬂavor obtained by deep fat frying, and reduces
the amount of oil content and polar compounds. However, it has not
been extensively studied and should receive a greater focus on the
detailed evaluation of components and properties of foods and the
eﬀects on the human health.
Deep frying; air frying;
Frying is one of the most common practices used in food preparation and employed in
restaurants, homes, and food industry. Fried food is based on dehydrating food that is
immersed in hot oil, a technique widely used all over the world. The rapidity and ease of
preparation, the relatively low price and the aggregation of desirable food properties, such as
color, texture, and taste, contribute to its overall use. These positive attributes are results of
physical and chemical changes during frying, including oxidation, hydrolysis, and polymer-
ization, which are related to chemical and physical modiﬁcations in the food products.
Few studies have focused on the biological consequences of the consumption of oil-fried
foods for humans. However, it has been found that the content of the polar compounds in
frying is associated with endothelial dysfunction, hypertension, and may berelated to a higher
chance of developing chronic diseases, especially those of the cardiovascular system. Also,
people who eat fried foods are more likely to develop obesity and intestinal diseases.
Despite all the restrictions, fried products are trendy and highly consumed both inside and
outside homes and are typically found in fast food dishes and many other food services.
However, because of the risks of a high-fat diet, there is an increasing tendency for consumers
to seek more nutritious and safer food alternatives. Therefore, the reduction of the oil content
in fried foods has become a necessity. A series of alternatives have been proposed, with the
intention of replacing the traditional frying process with systems capable of providing proper-
ties similar to those of fried food while providing higher nutritional quality to the product as
well as ease of use.
CONTACT Sandra Maria Barbalho email@example.com School of Medicine, University of Marília, Av. Higino
Muzzi Filho 1001, Marília 15525-902, SP, Brazil
Color versions of one or more of the ﬁgures in the article can be found online at www.tandfonline.com/lfri.
FOOD REVIEWS INTERNATIONAL
2019, VOL. 35, NO. 8, 763–777
© 2019 Taylor & Francis
Based on this idea, air frying technology has emerged in the market. The equipment uses hot
air in combination with high-speed air circulation. Foods are heated from all sides at once, and
there is no need to add oil to most of them. The proposal is to obtain fried food with small
amounts of fat. Its acceptability depends on, among other characteristics, the sensorial properties
of the ﬁnal product, which should approximate those present in the conventional frying
This review intends to gather information about the physicochemical changes that occur
in food submitted to the conventional and air frying process and compare the advantages
and disadvantages of these processes.
The focused objective for this review is to compare the conventional frying process and
the air frying process.
Inclusion and exclusion criteria
Studies related to conventional frying process and air frying process published in
MEDLINE–PubMed, Scielo and Google Scholar were included. Reviews and original
articles in English were selected. The exclusion criteria for this search were editorials,
case reports, poster presentations, and studies not in English or Portuguese.
For this review, we have searched Scielo, Google Scholar, and MEDLINE–PubMed
(National Library of Medicine, National Institutes of Health) databases for appropriate
articles addressing the focused question. The combination of descriptors used for this
search was “conventional frying and air frying”;“air frying and oxidation”;“air frying and
health.”With the list of references for these combinations of the keywords, we have
selected articles to build the results and to perform the discussion.
We did not restrict a speciﬁc period to do this review since the technology of air frying
is recent, and there are not many studies relating this type of process to the frying usually
performed with oil heated to high temperatures and immersion of the food for the
cooking process. Each author checked the screening of the articles found in the above-
described databases, and the articles were only used after the agreement of all.
Recently, air frying technology has become a viable alternative to deep fat frying since it
advocates the use of technology with little or no oil, and this, at least in theory, would
764 A. N. ZAGHI ET AL.
bring beneﬁts to maintaining health. On the other hand, the sensory characteristics that
conventional frying provides attract consumers worldwide.
Before presenting the discussion of the articles that fulﬁlled the eligibility criteria for the
search, it was necessary to collect some aspects related to the importance of frying in the food
industry as well as its relation with the resulting products to the process and its health
implications. The results for oxidation products such as acrylamide and health implications
may be found in Table 1.
We have found ﬁve original articles that fulﬁlled the eligibility
criteria for this search (Fig. 1). These articles are found in Table 2.
As may be
observed, only a few articles provide information about the air frying process.
The importance of frying in the food industry
The frying process is an eﬃcient and widely used method due to its rapidity and,
mainly, the supply of unique sensorial characteristics with much acceptance by the
population. The preservative eﬀect is another secondary character that results from the
thermal destruction of microorganisms and enzymes, in addition to a reduction of
water activity on the food surface. The shelf life of fried foods is determined, above all,
bythemoisturecontentafterfrying.Thosethatsuﬀer more dehydration through frying
(e.g., potato chips or corn chips), have a shelf life of up to twelve months at room
There are two main techniques of commercial frying that are distinguished by the
method of heat transfer: shallow frying and deep frying. Surface or contact frying consists
of heat transfer to the food mainly by conduction of the hot surface of the frying pan
through a thin layer of oil. This type of frying produces variable browning in the food,
preventing standardization of the product. In deep frying, the heat transfer is
a combination of convection in the hot oil and conduction into the food. All surfaces
receive similar heat treatment, producing uniform color and appearance.
The frying process can be continuous, which is usually used by the industrial market for
frying extruded snacks, fried pasta, pre-fried and fried potatoes, or discontinuous, which is
used mainly by the institutional market that includes fast food chains, restaurants, and
When the food is placed in hot oil, its surface temperature rises quickly, and
water evaporates. The surface then begins to dry. The evaporation plane moves into the
food, and a surface crust of porous structure is formed. Its rapid formation is beneﬁcial as
it maintains moisture in the food and restricts the rate of heat transfer to the interior. The
temperature used for frying is determined primarily by economic considerations and
product needs. At high temperatures (180–200°C), processing times are reduced, and
production rates are increased.
Concern about harmful health eﬀects due to the consumption of trans fatty acids has
led industries to substitute raw materials such as frying oils.
Substitution of saturated
to unsaturated fats, which is nutritionally and functionally favorable, involves a large
number of disadvantages. The high degree of unsaturation makes them unstable at high
temperature and more susceptible to oxidation, resulting in faster rancidity and alteration
of taste, thus limiting the shelf life of the ﬁnal product. Also, the sensory characteristics of
some of these oils may interfere with the taste of the food or lead to loss of crispness,
palatability, and taste.
FOOD REVIEWS INTERNATIONAL 765
During the heating of the oil, a number of reactions produce numerous degradation
compounds. With the continuity of the reactions, the functional, sensorial and nutritional
change leads to a low-quality product.
For these reasons frequent oil changes are necessary,
thus increasing costs. Also, there are amounts of degraded oil that are disposed of by users in
the environment. Furthermore, acrolein, a product of oil degradation characterized by the
formation of a bluish mist, is considered a source of air pollution.
Table 1. Eﬀects of the acrylamide on the human organism.
Reference Eﬀects on health Mechanisms of action
Lee et al.
Ataxia; skeletal muscle weakness; cognitive and
memory impairment; numbness of the
extremities; impaired hippocampal neurogenesis
and increased neural progenitor cell death;
mitochondrial dysfunction in primary neurons.
Since learning and memory are inﬂuenced by
neural plasticity as well as by hippocampal
neurogenesis, acrylamide-mediated memory
complications may be associated with changes
in brain plasticity which, when aﬀected, impair
the maturation of the primary neuron and the
proliferation of neuritis. Also, mitochondrial
dysfunction is related to oxidative stress by the
increase in the levels of reactive oxygen species.
Huang et al.
Augment in the incidence of thyroid follicular cell
tumors; scrotal sac mesotheliomas; mammary
gland ﬁbroadenomas and lung adenomas.
Acrylamide may exert its genotoxicity via DNA
alkylation, resulting in mutagenicity.
Decrease in the corticosterone and testosterone
levels; decrease in serum insulin level.
Acrylamide interferes with the reasonable
balance of several hormones. Prolonged and
chronic exposure can reduce blood insulin level
caused by reduction of beta cells.
Acrylamide is a neurotoxicant and can exert
reproductive and developmental toxicity eﬀects;
prenatal acrylamide exposure is associated with
impaired fetal growth and a moderate increase in
the prevalence of children being overweight or
One possible biological mechanism between
acrylamide exposure and growth is through
oxidative stress and inﬂammation. During
pregnancy, high acrylamide exposure can result
in increased oxidative stress through increased
expression of CYP2E1 leading to a heightened
perinatal inﬂammatory status.
Pan et al.
Induces a high risk of neuropathic alteration Evidence strongly suggested that acrylamide-
induced neurotoxicity was possibly caused by
the imbalance of oxidation and antioxidant
function, resulting from the elevated levels of
intracellular reactive oxygen species (ROS) and
Liu et al.
Increased overall mortality and cancer in the
digestive tract in elderly; induce changes in the
redox state of cells, transcription, and expression
of genes, interfering in DNA repair and hormonal
balances; breast cancer.
Acrylamide can cause cancer through non-
genotoxic mechanisms such as oxidative stress
after glutathione depletion. It may also alter the
levels of steroid hormones and interact with
genes involved in the production of sex
hormones, with circulating estrogen inﬂuencing
various factors and recognizing their
participation in the incidence of breast cancer.
Semla et al.
Production of free radicals, hydroperoxides and
Free radicals can damage mitochondria and
other cellular organelles. They induce apoptosis
and cause oxidation of DNA bases, fragmenting
the double strand leading to cell death or
Olesen et al.
Formation of adducts with proteins and DNA
Acrylamide is highly reactive and mutagenic
and can induce chromosomal breakage or
Sickles et al.
Aneuploidy; generation of micronuclei with
kinetochores; dominant lethal eﬀects; delays in
the cell cycle; blockages in mitosis and meiosis;
heritable translocations; chromosomal
Interaction of acrylamide with the proteins
involved in cell division, interfering in the
766 A. N. ZAGHI ET AL.
Degradation reactions in the frying process
During the frying process, oils and fats are exposed to the action of three agents that
contribute to decrease its quality and modify its structure. These agents include the
moisture from food (which is the cause of the hydrolytic alteration), the oxygen in the
air (which enters the oil through the surface of the cooking vessel, allowing the oxidative
change) and, the high temperature.
There are many changes in the properties of oils
and food, such as sensory (ﬂavor, aroma, texture, and color), nutritional, functional and
The most frequently observed physical changes in oils are increased
viscosity, color change and foaming.
Fig. 2 shows the modiﬁcations observed in the
For foods subjected to such a process, the possible results may be both desirable and
undesirable. For example, the color presented by the potato after frying directly implies its
acceptance. This visual characteristic is mainly inﬂuenced by the type of oil, the age and
thermal history of the oil, the interfacial tension between the oil and the product, the
temperature, the frying time and the sample size.
Duarte-Delgado et al.
that the sugar content also inﬂuences the color of the fried potatoes because the hydrolysis
of sucrose by the invertase enzyme is the primary source of glucose and fructose reducing
sugars, which are precursors of the Maillard reaction. This reaction produces dark
pigments and toxic products such as acrylamide during the non-enzymatic reaction
between free amino acids and reducing sugars at high temperatures. The high content
of reducing sugars in tubers causes a poor quality of potato chips.
The texture of fried foods is produced by changes in proteins, fats and polymeric
carbohydrates. Changes in protein quality occur as a result of the Maillard reaction with
the amino acids in the crust. The eﬀect of frying on the nutritional value of food depends
on the type of the of the process. As the high temperatures of the oils produce a rapid
Figure 1. Flow diagram depicting the articles selected for this review.
FOOD REVIEWS INTERNATIONAL 767
Table 2. Air frying versus conventional frying.
Reference Objective Analysis Technique Results
To compare samples
of chips processed in
air fryers versus
ascorbic acid; β-
Tocopherols Total ascorbic
β-carotene Total phenolics Total
4.60mg/100g 0.88mg/100g 167μm/100g 20.46mg gallic acid/100g 9.06mg gallic
Air frying 0.004g/100g
1.13mg/100g 1.44mg/100g 167.5μm/100g 27.21mg gallic acid/100g 7.27mg gallic
Evaluation of the
characteristics of the
chips processed by
the primary kitchen
nutritional quality of
15.79g/100g 94.5 μg/kg Time of cooking Consumption
13 minutes 270.4 Wh
Air frying Equipment 1 9.25g/100g 209.5 μg/kg 20 minutes 233.0 Wh
Equipment 2 9.14g/100g 89 μg/kg 16 minutes 193.8 Wh
Compare air frying
deep fat frying and
products formed by
Evaluation of oil and
color, texture, sensorial
Air and deep
The deep frying process: products with higher content of fat; similar moisture and color, better surface crust,
higher extend of starch gelatinization, and less time for preparation.
768 A. N. ZAGHI ET AL.
To investigate the
eﬀect that the air
exerts on the oil
content and sensorial
characteristics of the
potato, compared to
process of frying.
Stability of the oil and
sensory evaluation of
Oil degradation (180°C) Amount of used oil Amount of
Polar content Peroxides
value = 0,09%
value = 0,002%
value = 0,08%
value = 0,75
2kg for each 200g of
value = 0.22%
value = 0.11%
value = 0.71%
value = 2.75
Air frying Initial
value = 0.09%
value = 0.002%
value = 0.08%
value = 0.75
30g/kg potato 0.0025%
value = 0.12%
value = 0.06%
value = 0.34%
value = 1.22
Evaluation of volume
and inﬂuence of pre-
Analysis of the kinetics
of mass transfer and
Air and deep
-The ﬁnal content of oil is much lower in air frying.
-The heat transfer coeﬃcient for air frying was lower.
-Frozen samples showed the highest content of fat in the deep frying.
-The evolution in the content of oil in the unpretreated and blanched samples was much higher in the deep
frying as well as the water loss, and the frozen samples showed the lowest rate of water loss.
FOOD REVIEWS INTERNATIONAL 769
formation of crust, it seals the surface of the food, reducing the range of changes in the
interior and, consequently, there is signiﬁcant retention of nutrients.
Neethu et al.
also attributed changes in fried food quality to starch gelatinization reactions, protein
denaturation, caramelization, enzyme inactivation and fat absorption.
The oxidation of fat-soluble vitamins in the oil results in loss of nutritional value.
Retinol, carotenoids, and tocopherols are destroyed, contributing to changes in the
taste and color of the oil. However, the preferential oxidation of tocopherols has an
antioxidant eﬀect on the oil that is particularly important since most frying oils have
a vegetable origin and contain a substantial proportion of unsaturated fats that oxidize
Due to the knowledge that the frying process alters the chemical nature of the heated
oil, generating toxic compounds, the safety of the consumer and possible consequences for
the human organism are a concern.
Oxidized compounds and their eﬀects on health
The relevance of ingestion of vegetable oils in the human diet, especially those containing
essential fatty acids, primarily as energy-supplying food resources, is indisputable.
However, frying present limitations from the nutritional point of view and may pose
serious health risks.
Researchers have shown that products resulting from oils heated for long periods under
extremely high temperatures contain more than 50% polar compounds, which are the
products of the breakdown of triglycerides (polymers, dimers, free fatty acids and oxidized
fatty acids). These compounds lead to metabolic changes resulting in weight loss, suppres-
sion of growth, development of cancer, decrease in liver and kidney size, malabsorption of
Figure 2. Diagram of changes occurring during the frying process.
770 A. N. ZAGHI ET AL.
fat, decrease in the desaturation rate of linoleic and α-linolenic fatty acids, and reduced
Another toxic contaminant in a plethora of heat-treated foods is acrylamide, a polar
organic substance, highly reactive, mainly generated through the Maillard reaction.
commonly present in foods rich in carbohydrates that are processed at high temperatures
This compound is considered genotoxic and neurotoxic and has been related
to the development of cancer.
There is an estimate that the dietary exposure for the
population to acrylamide is around 1 mg kg-1 per day indicating that this scenario is
a human health concern.
The metabolism of acrylamide follows two central paths: epoxidation and conjugation
Once ingested, approximately 50% of the acrylamide is metabolized;
the biotransformation occurs in the cytochrome P450 by the action of the enzyme
CYP2E1 and, as a result, obtains its metabolite epoxy glycidamid.
the second phase of biotransformation, acrylamide and glycidamid are coupled to reduced
glutathione through glutathione S-transferase group enzymes, which constitute the glu-
tathione conjugation phase. As a result of this reaction, acrylamide and its derivatives lose
their toxic properties. Afterward, they are excreted as mercapturic acid derivatives by
urine, the main route of excretion of acrylamide metabolites in humans.
of acrylamide in the body is 2–7 hours, which demonstrates a long time that this substance
takes to be removed from the body. It is still unclear whether the toxic eﬀects of chronic
exposure to acrylamide may be cumulative in the organism in the long term.
eﬀects of acrylamide on health are described in Table 1.
Although there is awareness of the contraindications of the consumption of fried foods,
there are no signs that they suggest a withdrawal or change in the preparation or
consumption habits of these foods. However, current nutritional recommendations sug-
gest that fat intake should not exceed 30–35% of total calories, with a maximum of 10%
for saturated fats.
In this context, new technologies need to be developed to obtain fried
products with sensorial properties similar to those of the conventional frying process,
which are much appreciated by consumers, but with reduced fat content.
Air frying technology
An alternative found for the disadvantages of conventional frying is the air frying
process, which is intended to produce a variety of fried products using mainly hot air
around the material instead of immersion in hot oil. This technique acts by direct
contact between a ﬁne mist consisting of oil droplets in the hot air and the product
inside a chamber. The heat transfer is extremely high and evenly distributed in the
product, which minimizes variations in its quality. The product is dehydrated during
the process and a crust, typically associated with deep frying, appears gradually in the
Table 2 shows some comparisons of the air frying process compared to the
conventional frying process.
Air frying technology was initially introduced in some European markets and, due to
its remarkable acceptance in response, the product was launched throughout Europe. Over
time, it has spread on a global scale, becoming a great success worldwide. The patented
technology cooks products in a short time, keeping the taste pleasant and containing up to
80% less fat compared to frying by deep frying.
However, it is necessary to analyze
FOOD REVIEWS INTERNATIONAL 771
other possible advantages as well as disadvantages of this technology including modiﬁca-
tions in the properties of the food, besides making comparisons about the traditional
process of frying.
Comparison of air frying and deep fat frying Andrés et al.
, when comparing air
frying to deep frying, found that during the same frying time, the oil absorption in the
samples of French fries was about ten times greater for those submitted to hot oil. In
frozen potatoes subjected to deep frying, the oil content was substantially modiﬁed from
the original content. In the air frying process, a decrease of the concentration of the oil to
values of half the initial content was found. However, this reduction of oil content resulted
in the formation of a less consistent crust (leading to less resistance to water loss) and
interfered with the sensorial characteristic of the ﬁnal product. They also observed similar
moisture concentration when comparing to deep frying, but water and volume losses were
higher in air frying process. The loss of water is limited by the crust of the products, which
is formed rapidly in the deep frying process. Changes in oil content in both processes were
shown when samples of French fries were pretreated with blanching or freezing.
According to Teruel et al.
, the air frying process is capable of reaching the characteristic
color of frying by deep frying. The deep frying process results in products with lower content
of fat and similar moisture and color when compared to the air frying process. The authors
also observed interferences in color, texture, moisture, sensory characteristics, and starch
gelatinization. However, it requires a signiﬁcantly longer processing time (the use of air frying
requires more than twice the time of deep fat frying.), which is a relative disadvantage
considering that the current lifestyle (because people spend much of their time away from
home) requires agility and rapid preparation of meals. In general, the air frying process allows
the manufacture of a product that contains low fat content, although it exhibits diﬀerent
sensory characteristics such as taste, color, odor, appearance, hardness, crispness, crispiness,
and oiliness. In contrast, for Shaker
, air frying technology did not show signiﬁcant
diﬀerences in sensory attributes like taste, appearance, odor and overall acceptance when
compared to oil frying. In aspects such as crispness, hardness, oiliness, and color, air frying
was preferred. Nevertheless, potato strips prepared by air frying process showed superiority in
attributes such as hardness, crispness, and oiliness when compared to that traditional fried
potato. Thecharacteristics of better hardness and oiliness may be attributed to lower uptake of
oil compared to deep frying process.
Furthermore, studies using scanning electron microscopy (SEM) and diﬀerential scan-
show that the diﬀerence between products submitted to air
frying and immersion frying is the greater extent of gelatinization of the starch that occurs
in traditional frying, which is observed visually as a dry and thick crust. This is the result
of high temperatures rapidly reaching the surface of the product, causing intense evapora-
tion of the local water and preventing gelatinization of the starch. In products subjected to
air frying, the water evaporates more slowly, the surface crust is thinner, homogeneous
and without irregularities, which gives a noticeable diﬀerence in texture. However, in the
central region, the air frying samples presented higher hardness than the samples resulting
from immersion frying possibly related to a lower degree of gelatinization of the starch
associated with the low temperatures.
Tarmizi and Niranjan
studied the relationship of oil absorption in immersion frying,
and veriﬁed that it occurs predominantly at the end of the process, due to the condensa-
tion of water vapor inside the food caused by the temperature drop below the boiling
772 A. N. ZAGHI ET AL.
water, creating a water vapor pressure gradient between the surface and the inner
structure of the product. During frying, both water and water vapor are ﬁrst removed
from the large capillaries and replaced with hot oil.
Studies performed by Andres et al
show that the mass losses of the product in air
frying were higher than in immersion frying because the water lost during this process was
not compensated by any signiﬁcant oil absorption, in agreement with the results described
by Tamizi and Niranjan.
In addition to the diﬀerence in mass presented by the products submitted to the two types
of frying, color is one of the most important quality attributes to inﬂuence the consumer‘s
For example, the study by Pedreschi et al
reported that the frying process
in hot air requires a signiﬁcantly longer processing time to obtain the characteristic color of
potato chips in oil.
Budzaki and Seruga
, Farinu and Baik
, Mir-Bel et al.
, when measuring the
potatoes in the two frying conditions (oil and air), veriﬁed that the initial temperature
increased, almost linearly with time, until reaching the boiling point of the water, although
the deep frying reached the boiling point faster than frying in hot air. According to Teruel
the speed to reach the boiling point in oil frying is 3.7 times higher than in hot air. According
to the author, a constant temperature is observed in the frying process in the hot air when it
reaches the boiling point of the water until the end of the process, diﬀerent from the
signiﬁcant increase of temperature above 100ºC, observed in the frying in oil.
Authors agree that the air frying technology presents a higher nutritional quality than
conventional frying, being a practical alternative for obtaining healthier fried foods due to the
possibility of fat reduction, lipid degradation, and oxidation. Moreover, it also has environ-
mental advantages such as reduced consumption of oil, and emission of eﬄuents that would be
discarded after frying
According to Giovanelli et al.
, the air frying equipment showed
more signiﬁcant energy savings compared to others, corresponding to a savings of 70%.
The current context of changing eating habits in which society is inserted deserves
attention and suggests constant monitoring, mainly by the food industry. Since there is
no evidence of stopping the use of frying to prepare meals, it is recommended to use air
frying technology, since it has a proven reduction in the oil content of the products, once
the addition of the same is dispensed in the preparation of most foods.
The incorporation of air frying equipment in snack factories, in commercial establish-
ments such as fast food chains, restaurants and even for domestic use may be an
investment trend for the coming years. Among the advantages are the reduction of
expenses with vegetable oils, reduction of emission of pollutants in the environment and
energy saving, as well as the attraction of consumers who seek a healthier diet, which will
undoubtedly add value to the company.
Although the air frying technology is a healthier frying alternative it has not been
extensively studied and should receive a greater focus on the detailed evaluation of its
mechanisms of action on the components and properties of foods and consequent eﬀects
on the human health.
FOOD REVIEWS INTERNATIONAL 773
The concern over the increase in the incidence of chronic-degenerative diseases has increased the
search for a healthier diet. The substitution of food produced by deep fat frying is an increasingly
common reality since this type of processing carries with it the production of highly toxic
compounds in addition to being highly caloric. Air fryer technology may modify this scenario
since it does not produce toxic compounds and, on the other hand, preserves sensory characteristics
similar to deep fat frying.
Conﬂicts of interest
We declare no conﬂict of interests.
Notes on author contribution
ANZ, SMB, ELG and AMO designed, wrote and reviewed the manuscript. SMB submitted the
Sandra Maria Barbalho http://orcid.org/0000-0002-5035-876X
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