Integrated approach towards acrylamide reduction in potato-based snacks: A critical review

Effects of agronomical practices on potato growth, nutritional profile, and suitability for frying

BACKGROUND

This study investigated the effect of sulfur nutrition, basalt rock aggregate (BA) application, with a carbon capture function, and speed breeding under light-emitting diode (LED) light, on the nutritional profile of potatoes and acrylamide formation in crisp production.

RESULTS

Taurus potatoes grown with sulfur showed reduced glucose, sucrose, and total amino acids, and increased asparagine. No difference in acrylamide content was observed in crisps from Taurus and Lady Claire cultivars, with either sulfur or BA application. Speed breeding under LED light reduced plant height in all cultivars (50-60 cm) in comparison with controls (80-90 cm). Tubers grown under LED light exhibited higher levels of glucose and fructose, and increased formation of acrylamide in crisps (78.90% for Lady Claire, 592.58% for Taurus, and 70.25% for Desiree).

CONCLUSIONS

Sulfur fertilization could benefit certain potato cultivars by lowering sugar levels in the tubers. Basal rock aggregate can be applied safely during the growth of potatoes as an innovative tool for sequestering carbon dioxide (CO2) from the atmosphere, with no negative effect on tubers' nutritional profile and no influence on acrylamide formation in crisps. The LED light conditions proved to be unsuitable for potato growth, especially if the potatoes were destined for the frying industry, increasing both sugars and acrylamide content. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

High-speed computed tomography to visualise the 3D microstructural dynamics of oil uptake in deep-fried foods

Oil serves as both the high-temperature heating medium during deep-frying unit operations and a contributor to the organoleptic properties of deep-fried foods. Its absorption is linked to structural deformations during deep-frying that create pathways for oil to enter the food microstructure. This study proposes a 4D imaging system (three spatial dimensions and time) using fast synchrotron radiation tomography for in-situ visualisation during deep-frying and post-frying cooling to understand the mechanisms behind oil absorption. Using wheat flour dough as a model food system, we investigate the impact of frying oil temperature on structural deformation and pore formation in the crust and core, pore structure integrity, and oil uptake and distribution. The results show that higher temperatures lead to the formation of a distinguished crust with surface openings, facilitating greater oil absorption in small crust pores through capillary action. Comparing 3D microstructures attained at different frying oil temperatures, final oil content reaches 14.4% at 180 °C, 12.2% at 150 °C, and 1.3% at 120 °C, with temperature-dependent structural changes in pore connectivity and network integrity significantly impacting the rate of oil uptake and its distribution.

Analysis of Maillard reaction precursors and secondary metabolites in Chilean potatoes and neoformed contaminants during frying

Southern Chile native potatoes are an interesting raw material to produce novel snacks like colored potato chips. These novel products should be comprehensively evaluated for the presence of undesirable compounds such as acrylamide, 5-hydroxymethylfurfural and furan, the main neoformed contaminants in starchy rich fried foods. This study evaluated the neoformed contaminant levels and oil content on chips made from eleven Chilean potato accessions and compared them with commercial samples. The neoformed contaminant contents were related to Maillard reaction precursor levels (reducing sugars and asparagine) and secondary metabolites (phenolic compounds and carotenoids). Neoformed contaminants correlated well among them and were weakly correlated with reducing sugars and asparagine. Acrylamide level in native potato chips ranged from 738.2 to 1998.6 μg kg-1 while from 592.6 to 2390.5 μg kg-1 in commercial samples. Thus, there is need to implement neoformed contaminant mitigation strategies at different steps of the production chain of colored potato chips.

Acrylamide in alternative snacks to potato: A review

The snack food market has been changing to keep up with the growing demand for healthier products and, as a result, alternative products to traditional potato chips have been emerging to provide health-related benefits. Extrusion, frying, and baking are the main techniques used worldwide in the processing of snacks and are among the main reasons for the formation of toxic compounds induced by heat, such as acrylamide. This contaminant is formed during thermal processing in foods heated at high temperatures and rich in carbohydrates. Processed potato-based products have been pointed out as the main contributors to acrylamide dietary exposure. Many studies have been conducted on potato chips since the discovery of this contaminant in foods and research on the formation of acrylamide in snacks from other vegetables has begun to be conducted more recently. Thus, this review aims to present a detailed discussion on the occurrence of acrylamide in alternative vegetable snacks that are consumed as being healthier and to address relevant questions about the effectiveness of mitigation strategies that have been developed for these products. Through this research, it was observed that, depending on the vegetable, the levels of this contaminant can be quite variable. Alternative snacks, such as sweet potato, carrot and beetroot may also contain high levels of acrylamide and need to be monitored even more closely than potatoes snacks, as less information is available on these food products. Furthermore, various pretreatments (e.g. bleaching, immersion in solutions containing chemical substances) and processing conditions (heating methods, time, temperature) can reduce the formation of acrylamide (54-99 %) in alternative vegetable snacks.

Nutritional and anti-nutritional compositional analysis of transgenic potatoes with late blight resistance

Late blight, caused by the pathogen Phytophthora infestans, is a devastating disease affecting potato production globally, with adverse effects in Africa where limited access to fungicides exacerbates its impact. Outbreaks of late blight lead to reduced yields and substantial economic losses to potato farmers and agricultural systems. The development of resistant potato varieties, tailored to African agroecological conditions, offers a viable solution in mitigating the devastating effects of late blight on potato cultivation. Leading to this study, two consumer-preferred varieties, Victoria and Shangi, with high susceptibility to late blight were targeted for conferring late blight resistance through genetic engineering. This was achieved by inserting R genes from wild relatives of potato displaying resistance to the disease. The intended effect of conferring resistance to the late blight disease has been consistently observed over twenty experimental field trials spanning 8 years at three locations in Uganda and Kenya. In this study, we assessed whether the genetic transformation has led to any significant unintended effects on the nutritional and anti-nutritional composition of potato tubers compared to the non-transgenic controls grown under the same agroecological conditions. The compositional assessments were conducted on commercial-size potato tubers harvested from regulatory trials at three locations in Uganda and Kenya. Statistical analysis was conducted using two-way analysis of variance comparing transgenic and non-transgenic samples. Overall, the results showed that the transgenic and non-transgenic samples exhibited similar levels of nutritional and antinutritional components. Variations detected in the levels of the analysed components fell within the expected ranges as documented in existing literature and potato composition databases. Thus, we conclude that there are no biologically significant differences in the nutritional and anti-nutritional composition of transgenic and non-transgenic potato tubers engineered for resistance to late blight.

Toward a science-based classification of processed foods to support meaningful research and effective health policies

Processed foods have been part of the American diet for decades, with key roles in providing a safe, available, affordable, and nutritious food supply. The USDA Food Guides beginning in 1916 and the US Dietary Guidelines for Americans (DGA) since 1980 have included various types of commonly consumed processed foods (e.g., heated, fermented, dried) as part of their recommendations. However, there are multiple classification systems based on "level" of food processing, and additional evidence is needed to establish the specific properties of foods classified as "highly" or "ultra"-processed (HPF/UPFs). Importantly, many foods are captured under HPF/UPF definitions, ranging from ready-to-eat fortified whole grain breakfast cereals to sugar-sweetened beverages and baked goods. The consequences of implementing dietary guidance to limit all intake of foods currently classified as HPF/UPF may require additional scrutiny to evaluate the impact on consumers' ability to meet daily nutrient recommendations and to access affordable food, and ultimately, on health outcomes. Based on a meeting held by the Institute for the Advancement of Food and Nutrition Sciences in May 2023, this paper provides perspectives on the broad array of foods classified as HPF/UPFs based on processing and formulation, including contributions to nutrient intake and dietary patterns, food acceptability, and cost. Characteristics of foods classified as UPF/HPFs are considered, including the roles and safety approval of food additives and the effect of food processing on the food matrix. Finally, this paper identifies information gaps and research needs to better understand how the processing of food affects nutrition and health outcomes.

Acrylamide formation in air-fryer roasted legumes as affected by legume species and roasting degree: the correlation of acrylamide with asparagine and free sugars

Acrylamide is a well-recognized hazardous compound with known carcinogenic, genotoxic, neurotoxic, and reproductive toxic effects. This research aimed to investigate how different legume species and roasting durations influence acrylamide formation during air-fryer roasting. The study also examined the relationship between acrylamide formation and the levels of free asparagine and free sugars in different bean species. Asparagine content varies substantially across different bean species. Sucrose was the predominant sugar across all bean species, with smaller amounts of galactose and glucose. Air-fryer-roasted Wandu kong (garden pea) showed the highest acrylamide formation, followed by Ultari kong (kidney bean) and Heoktae (black soybean), in that order. Beans roasted for longer periods in an air fryer contained significantly higher levels of acrylamide. This study revealed a strong positive correlation between acrylamide formation and the level of free asparagine in the beans, highlighting the risks associated with certain legume species and air-fryer roasting durations.

Acrylamide in starchy foods subjected to deep-frying, 20 years after its discovery (2002-2022): a patent review

On the occasion of the 20th anniversary of the discovery of acrylamide in food, an analysis of patents related to the mitigation of this compound in food products obtained through immersion frying was carried out. For this purpose, a comprehensive search, compilation, and information analysis were conducted using free online databases such as Google Patents, Patenscope, and Lens. The search yielded a total of 79 patents within the considered time period (2002-2022). The countries with the highest number of granted patents were the United States, the European Union, and South Korea. The patents were classified into four main approaches: raw material modification (49%), application of pre-treatments (27%), process modification (16%), and measurement techniques (8%). Among the results, Frito-Lay, an American company, stands out as the food industry company with the highest number of granted patents, totaling 15. Based on this review, it is concluded that while a significant number of patents have been granted in recent years, there is still a lag in developing countries. Furthermore, more studies are needed to determine acrylamide in starchy food matrices subjected to immersion frying different from potatoes.

Reducing Acrylamide Formation Potential by Targeting Free Asparagine Accumulation in Seeds

Acrylamide is a probable carcinogen in humans and is formed when reducing sugars react with free asparagine (Asn) during thermal processing of food. Although breeding for low reducing sugars worked well in potatoes, it is less successful in cereals. However, reducing free Asn in cereals has great potential for reducing acrylamide formation, despite the role that Asn plays in nitrogen transport and amino acid biosynthesis. In this perspective, we summarize the efforts aimed at reducing free Asn in cereal grains and discuss the potentials and challenges associated with targeting this essential amino acid, especially in a seed-specific manner.

Identifying high-risk factors and mitigation strategies for acrylamide formation in air-fried lotus root chips: Impact of cooking parameters, including temperature, time, presoaking, and seasoning

This study was conducted to identify high-risk factors and mitigation strategies for acrylamide formation in air-fried lotus root chips by studying the impact of various cooking parameters, including temperature, time, presoaking, and pre-seasoning treatments. The temperature and time had a surprisingly high impact on acrylamide formation. The chips prepared at high temperatures with longer cooking times contained an extremely high acrylamide content, reaching 12,786 ng/g (e.g., 170°C/19 min). A particularly concerning discovery was that the chips with extremely high acrylamide content (up to 17 times higher than the EU benchmark level for potato chips) did not appear overcooked or taste burnt. Higher cooking temperatures required shorter cooking times to properly cook lotus root chips for consumption. A high temperature with a short cooking time (170°C/13 min) greatly benefited acrylamide reduction compared to low temperature with a long cooking time (150°C/19 min). Presoaking in a 0.1% acetic acid solution and pre-seasoning with 1% salt reduced acrylamide levels by 61% and 47%, respectively. However, presoaking in water, vinegar solution, and citric acid solution did not significantly decrease the acrylamide content in the chips. Furthermore, some seasonings significantly increased acrylamide levels (up to 7.4 times higher). For the first time, these findings underscore the high risks associated with air-frying lotus root chips without considering these factors. This study also provides proper air-frying parameters and pretreatment strategies for minimizing acrylamide formation in air-fried lotus chips.

Thermal Stability Enhancement of L-Asparaginase from Corynebacterium glutamicum Based on a Semi-Rational Design and Its Effect on Acrylamide Mitigation Capacity in Biscuits

Acrylamide is present in thermally processed foods, and it possesses toxic and carcinogenic properties. L-asparaginases could effectively regulate the formation of acrylamide at the source. However, current L-asparaginases have drawbacks such as poor thermal stability, low catalytic activity, and poor substrate specificity, thereby restricting their utility in the food industry. To address this issue, this study employed consensus design to predict the crucial residues influencing the thermal stability of Corynebacterium glutamicum L-asparaginase (CgASNase). Subsequently, a combination of site-point saturating mutation and combinatorial mutation techniques was applied to generate the double-mutant enzyme L42T/S213N. Remarkably, L42T/S213N displayed significantly enhanced thermal stability without a substantial impact on its enzymatic activity. Notably, its half-life at 40 °C reached an impressive 13.29 ± 0.91 min, surpassing that of CgASNase (3.24 ± 0.23 min). Moreover, the enhanced thermal stability of L42T/S213N can be attributed to an increased positive surface charge and a more symmetrical positive potential, as revealed by three-dimensional structural simulations and structure comparison analyses. To assess the impact of L42T/S213N on acrylamide removal in biscuits, the optimal treatment conditions for acrylamide removal were determined through a combination of one-way and orthogonal tests, with an enzyme dosage of 300 IU/kg flour, an enzyme reaction temperature of 40 °C, and an enzyme reaction time of 30 min. Under these conditions, compared to the control (464.74 ± 6.68 µg/kg), the acrylamide reduction in double-mutant-enzyme-treated biscuits was 85.31%, while the reduction in wild-type-treated biscuits was 68.78%. These results suggest that L42T/S213N is a promising candidate for industrial applications of L-asparaginase.

Chronotoxicity of Acrylamide in Mice Fed a High-Fat Diet: The Involvement of Liver CYP2E1 Upregulation and Gut Leakage

Acrylamide (ACR) is produced under high-temperature cooking of carbohydrate-rich foods via the Maillard reaction. It has been reported that ACR has hepatic toxicity and can induce liver circadian disorder. A high fat diet (HFD) could dysregulate liver detoxification. The current study showed that administration of ACR (100 mg/kg) reduced the survival rate in HFD-fed mice, which was more pronounced when treated during the night phase than during the day phase. Furthermore, ACR (25 mg/kg) treatment could cause chronotoxicity in mice fed a high-fat diet, manifested as more severe mitochondrial damage of liver during the night phase than during the day phase. Interestingly, HFD induced a higher CYP2E1 expressions for those treated during the night phase, leading to more severe DNA damage. Meanwhile, the expression of gut tight junction proteins also significantly decreases at night phase, leading to the leakage of LPSs and exacerbating the inflammatory response at night phase. These results indicated that a HFD could induce the chronotoxicity of ACR in mice liver, which may be associated with increases in CYP2E1 expression in the liver and gut leak during the night phase.

Production and Inhibition of Acrylamide during Coffee Processing: A Literature Review

Coffee is the third-largest beverage with wide-scale production. It is consumed by a large number of people worldwide. However, acrylamide (AA) is produced during coffee processing, which seriously affects its quality and safety. Coffee beans are rich in asparagine and carbohydrates, which are precursors of the Maillard reaction and AA. AA produced during coffee processing increases the risk of damage to the nervous system, immune system, and genetic makeup of humans. Here, we briefly introduce the formation and harmful effects of AA during coffee processing, with a focus on the research progress of technologies to control or reduce AA generation at different processing stages. Our study aims to provide different strategies for inhibiting AA formation during coffee processing and investigate related inhibition mechanisms.

Thermostability enhancement and insight of L-asparaginase from Mycobacterium sp. via consensus-guided engineering

Acrylamide alleviation in food has represented as a critical issue due to its neurotoxic effect on human health. L-Asparaginase (ASNase, EC 3.5.1.1) is considered a potential additive for acrylamide alleviation in food. However, low thermal stability hinders the application of ASNase in thermal food processing. To obtain highly thermal stable ASNase for its industrial application, a consensus-guided approach combined with site-directed saturation mutation (SSM) was firstly reported to engineer the thermostability of Mycobacterium gordonae L-asparaginase (GmASNase). The key residues Gly97, Asn159, and Glu249 were identified for improving thermostability. The combinatorial triple mutant G97T/N159Y/E249Q (TYQ) displayed significantly superior thermostability with half-life values of 61.65 ± 8.69 min at 50 °C and 5.12 ± 1.66 min at 55 °C, whereas the wild-type was completely inactive at these conditions. Moreover, its T_m value increased by 8.59 °C from parent wild-type. Interestingly, TYQ still maintained excellent catalytic efficiency and specific activity. Further molecular dynamics and structure analysis revealed that the additional hydrogen bonds, increased hydrophobic interactions, and favorable electrostatic potential were essential for TYQ being in a more rigid state for thermostability enhancement. These results suggested that our strategy was an efficient engineering approach for improving fundamental properties of GmASNase and offering GmASNase as a potential agent for efficient acrylamide mitigation in food industry. KEY POINTS: • The thermostability of GmASNase was firstly improved by consensus-guided engineering. • The half-life and T_m value of triple mutant TYQ were significantly increased. • Insight on improved thermostability of TYQ was revealed by MD and structure analysis.

Vacuum impregnation pre-treatment: A novel method for incorporating mono- and divalent cations into potato strips to reduce the acrylamide formation in French fries

The effect of different vacuum impregnation (VI) pre-treatments of potato strips [in water (control), NaCl, KCl or CaCl2 (0.1 M) for 10 and 15 min] on acrylamide formation in French fries after deep frying in sunflower oil at 175°C for 5 min was determined. The acrylamide content of fries prepared with potato strips pre-treated by VI in distilled water decreased from 0.82 to 0.24 µg/g when time increased to 15 min. Moreover, the acrylamide content of fries from 10 min-KCl pre-treatment (0.35 µg/g) decreased significantly to 0.04 µg/g when time was 15 min (p < 0.05). In comparison to control (10 min), the VI pre-treatment in KCl and NaCl for 15 min reduced the relative content of acrylamide by 95 and 91%, respectively, and VI in distilled water was able to decrease this value by 71%. Results indicated that monovalent cations (K and Na) were more effective in reducing acrylamide formation than divalent cation (Ca2+) when the VI pre-treatment time increased to 15 min. In conclusion, VI as a pre-treatment for mono- and divalent cations in fried potato production could be a useful technique in industrial applications to reduce acrylamide formation in fries in a short time.

Dissecting postharvest chilling injury through biotechnology

Paradoxically, refrigerating many fruits and vegetables destroys their quality, and may even accelerate their spoilage. This phenomenon, known as postharvest chilling injury (PCI), affects produce from tropical and subtropical regions and leads to economic and postharvest loss and waste. Low temperatures are used to pause the physiological processes associated with senescence, but upon rewarming, these processes may resume at an accelerated rate. Chilling-injured produce may be discarded for not meeting consumer expectations or may prematurely deteriorate. In this review, we describe progress made in identifying the cellular and molecular processes underlying PCI, and point to advances in biotechnological approaches for ameliorating symptoms. Further, we identify the gaps in knowledge that must be bridged to develop effective solutions to PCI.

Palliative effect of Moringa olifera-mediated zinc oxide nanoparticles against acrylamide-induced neurotoxicity in rats

Repeated acrylamide (ACR) exposure in experimental animals and humans causes variable degrees of neuronal damage. Because of its unique features, several green synthesized nanomaterials are explored for neuromodulatory activity. Hence, this study investigated the effect of green synthesized zinc oxide nanoparticles using Moriga olifera leaves extract (MO-ZnONP) against acrylamide (ACR)-induced neurobehavioral and neurotoxic impacts in rat. Forty male Sprague Dawley rats were distributed into four groups orally given distilled water, MO-ZnONP (10 mg/kg b.wt), ACR (20 mg/kg b.wt), or MO-ZnONP + ACR for 60 days. Gait quality and muscular, motor, and sensory function were assessed. Acetylcholinesterase (AChE), dopamine, catalase, malondialdehyde (MDA), and Zn brain contents were determined. Brain histopathology and immunohistochemical localization of the amyloid-β protein and abnormal Tau were performed. The results revealed that MO-ZnONP significantly reduced ACR-induced sensory dysfunctions, hind limb abnormality, and motor deficits. Additionally, the ACR-induced increase in dopamine and AChE were significantly supressed by MO-ZnONP. Besides, MO-ZnONP significantly restored catalase and Zn content but reduced increased MDA brain content resulting from ACR. Furthermore, the ACR-induced neurodegenerative changes and increased amyloid-β and phosphorylated Tau immunoexpression was significantly abolished by MO-ZnONP. Conclusively, MO-ZnONP could be used as a biologically effective compound for mitigating ACR's neurotoxic and neurobehavioral effects.

Potential of Low Cost Agro-Industrial Wastes as a Natural Antioxidant on Carcinogenic Acrylamide Formation in Potato Fried Chips

Acrylamide is classified as a toxic and a prospective carcinogen to humans, and it is formed during thermal process via Maillard reaction. In order to find innovative ways to diminish acrylamide formation in potato chips, several extracts of agricultural wastes including potato peels, olive leaves, lemon peels and pomegranate peels extracts were examined as a soaking pre-treatment before frying step. Total phenolic, total flavonoids, antioxidant activity, and the reduction in sugar and asparagine contents were additionally performed. Proximate composition of these wastes was found to be markedly higher in fat, carbohydrate and ash contents. Lemon peels and potato peels showed almost similar phenolic content (162 ± 0.93 and 157 ± 0.88 mg GAE /g, respectively) and exhibited strong ABTS and DPPH radical scavenging activities than the other wastes. The reduction percentage of reducing sugars and asparagine after soaking treatment ranged from 28.70 to 39.57% and from 22.71 to 29.55%, respectively. HPLC results showed higher level of acrylamide formation in control sample (104.94 mg/kg) and by using the wastes extracts of lemon peels, potato peels, olive leaves, and pomegranate peels succeeded to mitigate acrylamide level by 86.11%, 69.66%, 34.03%, and 11.08%, respectively. Thus, it can be concluded that the soaking of potato slices in the tested wastes extracts as antioxidant as pre-treatment before frying reduces the formation of acrylamide and in this way, the risks connected to acrylamide consumption could be regulated and managed.

Thermostability Improvement of L-Asparaginase from Acinetobacter soli via Consensus-Designed Cysteine Residue Substitution

To extend the application range of L-asparaginase in food pre-processing, the thermostability improvement of the enzyme is essential. Herein, two non-conserved cysteine residues with easily oxidized free sulfhydryl groups, Cys8 and Cys283, of Acinetobacter soli L-asparaginase (AsA) were screened out via consensus design. After saturation mutagenesis and combinatorial mutation, the mutant C8Y/C283Q with highly improved thermostability was obtained with a half-life of 361.6 min at 40 °C, an over 34-fold increase compared with that of the wild-type. Its melting temperature (T_m) value reaches 62.3 °C, which is 7.1 °C higher than that of the wild-type. Molecular dynamics simulation and structure analysis revealed the formation of new hydrogen bonds of Gln283 and the aromatic interaction of Tyr8 formed with adjacent residues, resulting in enhanced thermostability. The improvement in the thermostability of L-asparaginase could efficiently enhance its effect on acrylamide inhibition; the contents of acrylamide in potato chips were efficiently reduced by 86.50% after a mutant C8Y/C283Q treatment, which was significantly higher than the 59.05% reduction after the AsA wild-type treatment. In addition, the investigation of the mechanism behind the enhanced thermostability of AsA could further direct the modification of L-asparaginases for expanding their clinical and industrial applications.

Mitigation of Acrylamide in Potato Chips by Pre-drying and Pulsed Electric Field Treatment

The object of this work was to study the effects of preliminary vacuum drying (VD), pulsed electric field (PEF) treatment, frying temperature on color, oil uptake, and acrylamide (AA) content in fried potato chips. The results of this study indicated that an increase of frying temperature from 120 to 180°C led to a decrease of frying time of around 70% for untreated and PEF pre-treated samples. The color value of L* and a* decreased with the increase of frying temperature, and those values of the sample pre-treated by PEF were significantly higher compared to those obtained from untreated samples. The PEF pre-treatment promoted the reduction of oil content of fried samples by up to 17.6, 14.2, and 16% compared with untreated samples at the frying temperatures of 120, 150, and 180°C, respectively. Higher efficiency was observed by applying the preliminary VD in the case of the frying temperature of 150°C. Furthermore, it was revealed that PEF pre-treatment and preliminary VD application lead to a synergetic effect on the reduction of AA content in potato chips. For example, with the initial moisture ratio of 0.5, pre-dried by VD and pre-treated by PEF, the AA content was noticeably decreased from 2,220 to 311 μg/kg compared to untreated and undehydrated samples at the frying temperature of 150°C. Our findings provide reference for a new pre-treatment to mitigate AA formation and to improve the quality of potato chips.