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Food Reviews International
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Frying Process: From Conventional to Air Frying Technology
Aline Nalon Zaghi, Sandra Maria Barbalho, Elen Landgraf Guiguer & Alda Maria Otoboni
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, 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 Zaghia, Sandra Maria Barbalho a,b, Elen Landgraf Guiguera,b, and Alda Maria Otobonia
aDepartment of Food Technology, Food Technology School, São Paulo, Brazil;bMedical School of Marília, UNIMAR, São Paulo, Brazil
ABSTRACT
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 similarflavor 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.
KEYWORDS Deep frying; air frying;
acrylamide
Introduction
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.[1,2]
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 be related 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.[3–6]
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.[7–9]
CONTACTSandra Maria Barbalho [email protected] School of Medicine, University of Marília, Av. Higino Muzzi Filho 1001, Marília 15525-902, SP, Brazil
Color versions of one or more of thefigures in the article can be found online atwww.tandfonline.com/lfri.
© 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 process.[10]
Objective
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.
Methods
Focused objective
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.
Databases
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.
Results
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
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 inTable 1.[11–19]We have foundfive original articles that fulfilled the eligibility criteria for this search (Fig. 1). These articles are found in Table 2.[7,10,20–22] As may be observed, only a few articles provide information about the air frying process.
Discussion
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, by the moisture content after frying. Those that suffer more dehydration through frying (e.g., potato chips or corn chips), have a shelf life of up to twelve months at room temperature.[22–25]
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.[25–27]
The frying process can becontinuous, which is usually used by the industrial market for frying extruded snacks, fried pasta, pre-fried and fried potatoes, ordiscontinuous, which is used mainly by the institutional market that includes fast food chains, restaurants, and pastries.[28] 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.[25,27]
Concern about harmful health effects due to the consumption of trans fatty acids has led industries to substitute raw materials such as frying oils.[29–31]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 thefinal 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.[32–35]
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.[36]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.[7,11,13,25,37]
Table 1.Effects of the acrylamide on the human organism.
Reference Effects on health Mechanisms of action
Lee et al.[11] 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.[12] Augment in the incidence of thyroid follicular cell tumors; scrotal sac mesotheliomas; mammary glandfibroadenomas and lung adenomas.
Acrylamide may exert its genotoxicity via DNA alkylation, resulting in mutagenicity.
Stošić, Matavulj,
Marković[13] 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.
Kadawathagedara et al.[14]
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 obese.
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.[15] 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 lipid peroxidation.
Liu et al.[16] 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.[17] Production of free radicals, hydroperoxides and lipid peroxidation.
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 neoplastic transformation.
Olesen et al.[18] Formation of adducts with proteins and DNA bases.
Acrylamide is highly reactive and mutagenic and can induce chromosomal breakage or degradation.
Sickles et al.[19] Aneuploidy; generation of micronuclei with kinetochores; dominant lethal effects; delays in the cell cycle; blockages in mitosis and meiosis;
heritable translocations; chromosomal aberrations.
Interaction of acrylamide with the proteins involved in cell division, interfering in the mitotic/meiotic spindle.
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.[38] There are many changes in the properties of oils and food, such as sensory (flavor, aroma, texture, and color), nutritional, functional and toxicity qualities.[39]The most frequently observed physical changes in oils are increased viscosity, color change and foaming.[40] Fig. 2 shows the modifications observed in the frying process.
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.[10,39] Duarte-Delgado et al.[41] showed 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.
Table2.Airfryingversusconventionalfrying. ReferenceObjectiveAnalysisTechniqueResults Santos etal., 2017[10]
Tocomparesamples ofchipsprocessedin airfryersversus traditionalfrying method Lipidcomposition; indicatorsof degradation; tocopherols;total ascorbicacid;β- carotene;antioxidant activity Conventional fryingwith soyoil
TransFatty AcidsTocopherolsTotalascorbic acidβ-caroteneTotalphenolicsTotal antioxidant activity 0.026g/100g potato4.60mg/100g0.88mg/100g167μm/100g20.46mggallicacid/100g9.06mggallic acid/100g Airfrying0.004g/100g potato1.13mg/100g1.44mg/100g167.5μm/100g27.21mggallicacid/100g7.27mggallic acid/100g Giovanelli etal., 2017[7]
Evaluationofthe characteristicsofthe chipsprocessedby theprimarykitchen equipment.
Equipment performance; nutritionalqualityof thesamples; acrylamidecontent Conventional fryingwith soyoil
LipidsAcrylamide contentEnergyconsumption 15.79g/100g94.5μg/kgTimeofcookingConsumption 13minutes270.4Wh AirfryingEquipment19.25g/100g209.5μg/kg20minutes233.0Wh Equipment29.14g/100g89μg/kg16minutes193.8Wh Teruel etal., 2015[20]
Compareairfrying withconventional deepfatfryingand productsformedby theseprocesses (color,texture, calorimetric properties,and sensorycharacteristic) Evaluationofoiland moisturecontent, color,texture,sensorial analysisand calorimetry.
Airanddeep fryingThedeepfryingprocess:productswithhighercontentoffat;similarmoistureandcolor,bettersurfacecrust, higherextendofstarchgelatinization,andlesstimeforpreparation.
Shaker, 2014[21]Toinvestigatethe effectthattheair fryingtechnology exertsontheoil contentandsensorial characteristicsofthe potato,comparedto thetraditional processoffrying.
Stabilityoftheoiland sensoryevaluationof Frenchfries Conventional fryingwith soyoil Oildegradation(180°C)AmountofusedoilAmountof absorbedoilFreefatty acidsOxidizedfatty acidsPolarcontentPeroxides Initial value=0,09%Initial value=0,002%Initial value=0,08%Initial value=0,75 meq.O2/kgoil
2kgforeach200gof potato14.81% Afterfrying value=0.22%Afterfrying value=0.11%Afterfrying value=0.71%Afterfrying value=2.75 meq.O2/kg óleo AirfryingInitial value=0.09%Initial value=0.002%Initial value=0.08%Initial value=0.75 meq.O2/kg óleo
30g/kgpotato0.0025% Afterfrying value=0.12%Afterfrying value=0.06%Afterfrying value=0.34%Afterfrying value=1.22 meq.O2/kg oil Andres etal., 2012[22]
Evaluationofvolume andinfluenceofpre- treatment(blanching andfreezing).
Analysisofthekinetics ofmasstransferand modificationsin volume.
Airanddeep frying.-Thefinalcontentofoilismuchlowerinairfrying. -Theheattransfercoefficientforairfryingwaslower. -Frozensamplesshowedthehighestcontentoffatinthedeepfrying. -Theevolutioninthecontentofoilintheunpretreatedandblanchedsampleswasmuchhigherinthedeep fryingaswellasthewaterloss,andthefrozensamplesshowedthelowestrateofwaterloss.
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.[25] Neethu et al.[42]
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 quickly.[25,43,44]
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.[45,46]
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.
fat, decrease in the desaturation rate of linoleic andα-linolenic fatty acids, and reduced fertility.[12,14,15,40,47]
Another toxic contaminant in a plethora of heat-treated foods is acrylamide, a polar organic substance, highly reactive, mainly generated through the Maillard reaction.[17]It is commonly present in foods rich in carbohydrates that are processed at high temperatures (>120°C).[16]This compound is considered genotoxic and neurotoxic and has been related to the development of cancer.[48] 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.[37,49]
The metabolism of acrylamide follows two central paths: epoxidation and conjugation with glutathione.[18]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.[17,50] During 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.[16,18]The half-life 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.[17] Some effects of acrylamide on health are described inTable 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.[32]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.[21]
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 productsusing 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 food.[20,21] 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.[51] However, it is necessary to analyze
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.[22], 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 thefinal 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.[20], 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[21], 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. The characteristics 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- ning calorimetry(DSC)[20] 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[52]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
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[22] 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.[52]
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 food choices.[53]For example, the study by Pedreschi et al[54]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[55], Farinu and Baik[56], Mir-Bel et al.[57], 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[20], 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[10,21,22]According to Giovanelli et al.[7], the air frying equipment showed more significant energy savings compared to others, corresponding to a savings of 70%.
Conclusion
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.
Practical applications
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 manuscript.
ORCID
Sandra Maria Barbalho http://orcid.org/0000-0002-5035-876X
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