Acrylamide content and color development in fried potato strips

Effect of Oat Fiber Preparations with Different Contents of β-Glucan on the Formation of Acrylamide in Dietary Bread (Rusks)

In the literature, there are few reports indicating hydrocolloids as a factor capable of reducing the amount of acrylamide formed in food. Therefore, the aim of the study was to examine the ability of soluble oat fiber to reduce the amount of acrylamide formed in the process of obtaining rusks. The effect of the concentration of β-glucans in oat fiber preparations at 20% and 30% and the amount of preparations used at 10%, 15%, and 20% was investigated. On the basis of the obtained test results, it was shown that the most optimal concentration of oat fiber preparation in rusks recipe is at 15%, regardless of the content of β-glucan in it. This concentration makes it possible to reduce the amount of acrylamide formed in baked goods and rusks by ~70% and ~60%, respectively, while maintaining the desired physical and chemical properties of the product. In addition, it was shown that the browning index and water activity strongly correlate with the content of acrylamide in rusks, which makes them good markers of this compound in rusks. The use of hydrocolloids in the form of oat fiber preparations with different contents of β-glucan as a tool for reducing the amount of acrylamide in rusks, at the same time, offers the possibility of enriching these products with a soluble dietary fiber with health properties.

Study the interaction of amino acids, sugars, thermal treatment and cooking technique on the formation of acrylamide in potato models

This study unveiled the effect of the suspected precursors of acrylamide (asparagine, glutamine) combined/separated with different formulations of glucose, fructose, and sucrose. To better understand the interaction between acrylamide precursors, cooking technique (deep vs air frying), and temperature (170 °C vs 190 °C), seven potato models from starch, sugars, amino acids, water and hydrocolloids (alginate and agar) were formulated. In line with previous findings, the present results showed that asparagine, glucose and fructose played an important role in acrylamide formation in these synthetic potato models. Furthermore, glutamine and sodium alginate might have an inhibitory effect on acrylamide formation. A significant impact of frying technique was also revealed. On the other hand, GC-FID analysis detected acrylamide in only these three models, (glucose-fructose, sucrose and asparagine-glucose/fructose/sucrose models > LOD 333.33 µg.kg^-1).

Study of Potential Synergistic Effect of Probiotic Formulas on Acrylamide Reduction

Acrylamide (AA) is a food processing contaminant commonly found in fried and baked food products. In this study, the potential synergistic effect of probiotic formulas in reducing AA was studied. Five selected probiotic strains (Lactiplantibacillus plantarum subsp. plantarum ATCC14917 (L. Pl.), Lactobacillus delbrueckii subsp. bulgaricus ATCC11842 (L. B.), Lacticaseibacillus paracasei subsp. paracasei ATCC25302 (L. Pa), Streptococcus thermophilus ATCC19258, and Bifidobacterium longum subsp. longum ATCC15707) were selected for investigating their AA reducing capacity. It was found that L. Pl. (10⁸ CFU/mL) showed the highest AA reduction percentage (43-51%) when exposed to different concentrations of AA standard chemical solutions (350, 750, and 1250 ng/mL). The potential synergistic effect of probiotic formulas was also examined. The result demonstrated a synergistic AA reduction effect by the probiotic formula: L. Pl. + L. B., which also showed the highest AA reduction ability among the tested formulas. A further study was conducted by incubating selected probiotic formulas with potato chips and biscuit samples followed by an in vitro digestion model. The findings demonstrated a similar trend in AA reduction ability as those found in the chemical solution. This study firstly indicated the synergistic effect of probiotic formulas on AA reduction and its effect was also highly strain-dependent.

Formation and mitigation of acrylamide in oven baked vegetable fries

Investigation into oven baked sweet potato and carrot fries at various temperatures and times demonstrated the in situ formation of acrylamide in an exponential manner. High levels of acrylamide were found in these food items: up to 327 µg/kg for sweet potato baked at 190 °C for 14 min, and 99 µg/kg for carrot baked at 190 °C for 13 min. Risk assessment via Margin of Exposures estimation showed that consumption of these fries might pose adverse health effects to consumers from toddlers to adults, especially when the fries were prepared at high temperatures above 175 °C and for a long time. Raw ingredient blanching and immersion in acetic acid prior to preparation have been proven to greatly reduce acrylamide formation, up to 99%. It is recommendable to apply these techniques either at industrial or domestic cooking scales to ensure minimal health risk from dietary exposure to acrylamide.

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.

Dietary Acrylamide Intake Alters Gut Microbiota in Mice and Increases Its Susceptibility to Salmonella Typhimurium Infection

Acrylamide (AA) has been extensively examined for its potential toxicological effects on humans and animals, but its impacts on gut microbiota and effects on hosts’ susceptibility to enteric infection remain elusive. The present study was designed to evaluate the effect of AA on gut microbiota of mice and susceptibility of mice to S. Typhimurium infection. After four weeks’ intervention, mice fed with AA exhibited significantly decreased body weight. Meanwhile, 16S rRNA gene sequencing showed reduced relative abundance of Firmicutes and increased abundance of Bacteroidetes in AA-treated mice prior to infection. In addition, we observed high relative abundance of Burkholderiales and Erysipelotrichales, more specifically the genus Sutterella and Allobaculum, respectively, in AA-treated mice before infection. Subsequently, the mice were orally infected with S. Typhimurium. The histological changes, systemic dissemination of S. Typhimurium, and inflammatory responses were examined. Compared to mice fed with normal diet, mice fed AA exhibited higher level of bacterial counts in liver, spleen, and ileum, which was consistent with exacerbated tissue damage determined by histological analyses. In addition, higher expression of pro-inflammaroty cytokines, p-IκBα, and p-P65 and lower mRNA expressions of mucin2, occludin, zo-1, claudin-1, and E-cadherin were detected in AA-treated mice. These findings provide novel insights into the potential health impact of AA consumption and the detailed mechanism for its effect on S. Typhimurium infection merit further exploration.

Functionalized Biscuits with Bioactive Ingredients Obtained by Citrus Lemon Pomace

In this study, functionalized biscuits were prepared through the enrichment of dough with lemon peel and natural antioxidants extracted from lemon pomace. Lemon pomace extract (LP_E) was analyzed for total phenolic content before addition, and then a known concentration of 50 mg kg⁻¹ was used for the formulation of enriched biscuits. Three different biscuit samples were compared to a control biscuit, without the addition of functional ingredients. The main physicochemical, microbiological, and sensory aspects of doughs and biscuits enriched with LP_E were investigated. The enriched biscuits showed higher phenolic content and antioxidant activity than the control one and a longer induction period (IP), which means that the enriched products had a higher intrinsic resistance to lipid oxidation, thanks to the antioxidant effect exerted by the added fresh lemon peel and the LP_E. Furthermore, from a sensorial point of view, they showed suitable acceptability, in terms of appearance, flavor, and aromatic attributes. Thus, results indicated that the incorporation of lemon processing by-products allowed the production of functional enriched biscuits with improved antioxidant properties.

Kinetics of Colour Development during Frying of Potato Pre-Treated with Pulsed Electric Fields and Blanching: Effect of Cultivar

The current research aimed to investigate the effect of pulsed electric fields (1 kV/cm; 50 and 150 kJ/kg) followed by blanching (3 min., 100 °C) on the colour development of potato slices during frying on a kinetic basis. Four potato cultivars 'Crop77', 'Moonlight', 'Nadine', and 'Russet Burbank' with different content of glucose and amino acids were used. Lightness (L* values from colorimeter measurement) was used as a parameter to assess the colour development during frying. The implementation of PEF and blanching as sequential pre-treatment prior to frying for all potato cultivars was found effective in improving their lightness in the fried products. PEF pre-treatment did not change the kinetics of L* reduction during frying (between 150 and 190 °C) which followed first-order reaction kinetics. The estimated reaction rate constant (k) and activation energy (E_a based on Arrhenius equation) for non-PEF and PEF-treated samples were cultivar dependent. The estimated E_a values during the frying of PEF-treated 'Russet Burbank' and 'Crop77' were significantly (p < 0.05) lower (up to 30%) than their non-PEF counterparts, indicating that the change in k value of L* became less temperature dependence during frying. This kinetic study is valuable to aid the optimisation of frying condition in deep-fried potato industries when PEF technology is implemented.

Effect of consumer's decisions on acrylamide exposure during the preparation of French fries. Part 2: Color analysis

Two observational tests were designed to investigate the influence of consumer decisions during the preparation of French fries from fresh potatoes on acrylamide formation. In both tests, color was of paramount importance to volunteers with regards to the decision to stop the frying process. CIE-Lab* color parameters and visual color assessments of French fries were associated with general acrylamide content and its classification according to the EU benchmark levels (BL, 500 μg/kg). Binary logistic regression analysis revealed that color parameter a* was the main factor in determining the probability of acrylamide content being above BL, regardless of the culinary practices applied. A cut-off of 0.855 for a* produced the greatest sensitivity (81.1%) and specificity (99.9%) for classifying samples with acceptable BL of acrylamide content. An increase of one unit of a* more than quadruple the risk of acrylamide content not falling within BL. When no external color reference was provided, volunteers misclassified 33.6% of fries as having a golden color. Harmonized criteria based on a reference color chart that indicates a golden color are necessary for producing fries with reduced acrylamide contents and, in this way, limit the risk of exposure to acrylamide in domestic settings.

Acrylamide-induced peripheral neuropathy: manifestations, mechanisms, and potential treatment modalities

Acrylamide is a chemical monomer; its polymer compounds are used in the manufacture of plastic, papers, adhesive tapes, dyes, and food packaging. Lately, scientists found that cooking (mainly roasting, baking, and frying) yields acrylamide. In addition to fried/baked potatoes, coffee and bakery products still contain substantial amounts of acrylamide. Acrylamide has toxic effects on different body systems include genitourinary, reproductive, nervous system, along with being a carcinogenic substance. The neurotoxicity of acrylamide includes central and peripheral neuropathy. In humans, the clinical manifestations include sensory or motor peripheral neuropathy, drowsiness, or cerebellar ataxia. Likewise, it presents with skeletal muscle weakness, hindlimb dysfunction, ataxia, and weight loss in animals. The suggested mechanisms for acrylamide neurotoxicity include direct inhibition of neurotransmission, cellular changes, inhibition of key cellular enzymes, and bonding of kinesin-based fast axonal transport. Moreover, it is suggested that acrylamide's molecular effect on SNARE core kinetics is carried out through the adduction of NSF and/or SNARE proteins. Lately, scientists showed disruption of focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (Pyk2) cell signaling pathways in human differentiating neuroblastoma SH-SY5Y cells, exposed to acrylamide. Different treatment modalities have been revealed to shield against or hasten recovery from acrylamide-induced neuropathy in preclinical studies, including phytochemical, biological, and vitamin-based compounds. Still, additional studies are needed to elucidate the pathogenesis and to identify the best treatment modality.

Mitigation effects of phlorizin immersion on acrylamide formation in fried potato strips

BACKGROUND

Several researches reported that natural polyphenols affected acrylamide formation of fried products. However, the effects of different variety of polyphenols on acrylamide formation were distinct. In this study, we isolated and purified phlorizin from apples and identified the influence of phlorizin immersion on acrylamide formation and sensory properties of fried potato strips with regard to the immersion concentration, time and temperature.

RESULTS

The acrylamide formation of fried samples decreased as the phlorizin concentration increased from 0 to 0.3 g kg^-1 , and 0.14 g kg^-1 could be selected as the suitable immersion concentration to dramatically inhibit acrylamide formation with considering the cost of industrial production. Additionally, the acrylamide formation significantly reduced from 8.71 × 10^-3 to 2.13 × 10^-3 g kg^-1 lyophilized weight (LW) with immersion time from 0 to 120 min, and 60 min could be selected to significantly reduce acrylamide formation in consideration of efficiency of the large-scale industrial processing. However, the effect of phlorizin immersion temperature on acrylamide formation of fried samples was not significant. Compared to the fried samples without immersion, the phlorizin immersion improved the color properties and the change of texture parameters was slight.

CONCLUSION

The fresh potato strips immersed in the phlorizin solution of 0.14 g kg^-1 at 40 °C for 60 min before frying could significantly decrease acrylamide formation of fried samples and retain the majority of fresh sensorial properties. The significant correlations obtained between sensory properties and acrylamide content indicated the sensory properties could be used as the indicator of acrylamide levels during industrial processing. © 2020 Society of Chemical Industry.

Effect of Microwave Heating on the Acrylamide Formation in Foods

Acrylamide (AA) is a neurotoxic and carcinogenic substance that has recently been discovered in food. One of the factors affecting its formation is the heat treatment method. This review discusses the microwave heating as one of the methods of thermal food processing and the influence of microwave radiation on the acrylamide formation in food. In addition, conventional and microwave heating were compared, especially the way they affect the AA formation in food. Available studies demonstrate differences in the mechanisms of microwave and conventional heating. These differences may be beneficial or detrimental depending on different processes. The published studies showed that microwave heating at a high power level can cause greater AA formation in products than conventional food heat treatment. The higher content of acrylamide in microwave-heated foods may be due to differences in its formation during microwave heating and conventional methods. At the same time, short exposure to microwaves (during blanching and thawing) at low power may even limit the formation of acrylamide during the final heat treatment. Considering the possible harmful effects of microwave heating on food quality (e.g., intensive formation of acrylamide), further research in this direction should be carried out.

In Vitro and In Vivo Evaluation of the Protective Potential of Moringa oleifera Against Dietary Acrylamide-induced Toxicity

Background:

A c rylamide (AA) in food is a public health concern that has attracted scientists’ attention worldwide.

Objective:

This study was carried out to investigate the efficiency of Moringa oleifera (M. olifera) leaves in the reduction of AA in French fries in vitro and its hepato-protective properties against AA-induced liver toxicity in vivo.

Materials and Methods:

Total phenolic, flavonoid, tannin contents and antioxidant potential of M. oleifera leaves were evaluated and the phenolic constituents characterized via HPLC. AA content was also monitored in French fries using LC-MS/MS. For in vivo assay, mice were treated with AA alone or in combination with M. oleifera (150 and 250 mg/kg IP).

Results:

Phytochemical screening showed that gallic acid, ellagic acid, epicatechin, and quercetin were the most abundant phenolic compounds identified. This work also demonstrated a nearly 37% reduction in AA when French fries were soaked in 1% M. oleifera. Moreover, AA-intoxicated mice resulted in a significant (P < 0.05) elevation in the liver enzyme alanine aminotransferase (ALT), which was restored when pre-treated with M. oleifera.

Conclusion:

This study proved that M. olifera could be effective in reducing AA levels in French fries and that treatment with M. oleifera extract can restore the hepatic damage in AA-intoxicated mice.

Are Household Potato Frying Habits Suitable for Preventing Acrylamide Exposure?

A survey was conducted of 730 Spanish households to identify culinary practices which might influence acrylamide formation during the domestic preparation of french fries and their compliance with the acrylamide mitigation strategies described in the 2017/2158 Regulation. Spanish household practices conformed with the majority of recommendations for the selection, storing and handling of potatoes, with the exception of soaking potato strips. Olive oil was the preferred frying oil (78.7%) and frying pans were the most common kitchen utensils used for frying (79.0%), leading to a higher oil replacement rate than with a deep-fryer. Although frying temperature was usually controlled (81.0%), participants were unaware of the maximum temperature recommended for preventing acrylamide formation. For french fries, color was the main criteria when deciding the end-point of frying (85.3%). Although a golden color was preferred by respondents (87.3%), color guidelines are recommended in order to unify the definition of “golden.” The results conclude that habits of the Spanish population are in line with recommendations to mitigate acrylamide during french fry preparation. Furthermore, these habits do not include practices that risk increasing acrylamide formation. Nevertheless, educational initiatives tailored towards consumers would reduce the formation of this contaminant and, consequently, exposure to it in a domestic setting.

The Effect of UV-C Stimulation of Potato Tubers and Soaking of Potato Strips in Water on Color and Analyzed Color by CIE L*a*b*

The color of French fries is an organoleptic attribute indicative of this product quality and also a reliable indicator of its safety. The darker the product color, the higher its acrylamide concentration. Acrylamide is an organic compound of the amide group showing neurotoxic and potential mutagenic actions in the human body. The content of acrylamide in fried potato products essentially depends on the contents of reducing sugars in intermediates of French fries’ production. The present study aimed to investigate the effect of UV-C irradiation and the soaking of potato strips in water on French fries’ color. The study was conducted on French fries obtained from tubers of the Innovator variety. The study was performed with the use of a special chamber for UV-C irradiation of biological samples and the CIE L*a*b* model for color analysis. The results of the study demonstrated that UV-C stimulation of potato tubers before processing had a beneficial effect on French fries’ color while the blanching of potato strips and soaking in water at a temperature of 40 °C resulted in the production of French fries lighter in color.

Effect of acid on glycoalkaloids and acrylamide in French fries

The effects of acid soaking as a pre-treatment on the glycoalkaloid and acrylamide levels in raw and cooked potatoes (French fries) were examined. Soaking raw potato cuts in 1.0%, 2.5% or 5.0% acetic acid solutions for at least 8 hours resulted in >90% reduction of α-solanine and α-chaconine in potato samples. Processing of pre-acid soaked potato cuts into French fries resulted in an additional >50% decrease in the glycoalkaloid contents in the samples. Soaking time was found to be a more important factor in reducing glycoalkaloid levels compared to the acid solution concentrations. Over a 95% reduction in acrylamide was also observed in potato cuts pre-soaked in acetic acid before cooking. The reduction in acrylamide formation in the pre-soaked French fry samples was attributed to the lowered pH and the removal of reducing sugars and asparagine in the raw samples prior to cooking. Findings in this study demonstrate that pre-treatment using acid soaking provides a simple and effective way to mitigate glycoalkaloid and acrylamide levels in potatoes.

Acrylamide in French fries prepared at primary school canteens

Children are one of the most exposed groups to dietary acrylamide with ‘potato fried products’ that account for up to half the total exposure to this contaminant.

Alternative food matrices for snack formulations in terms of acrylamide formation and mitigation

BACKGROUND

The salty snack market is re-inventing itself trying to offer to consumers healthier and added-value products often based on alternative vegetables/cereals, such as vegetable chips. New options mostly involve a nutritional improvement but the toxicological aspects of the reformulation are not usually examined. This work evaluated the acrylamide formation and effectiveness of different mitigation strategies in potato chips and in alternative snacks, such as carrot and pumpkin chips. Fresh potato, carrot and pumpkin samples were fried under controlled conditions and after being subjected to different operations (soaking in water at different times/temperatures, adding lemon or vinegar as pH modifiers or salt).

RESULTS

Acrylamide values in control samples of carrot (224 ± 47 µg kg^-1 ) and pumpkin (514 ± 83 µg kg^-1 ) were significantly lower than in the potato chip samples (3887 ± 509 µg kg^-1 ). The different mitigation treatments had effects on potato and pumpkin chips, the most effective strategies being soaking options and the decrease of the pH of the medium. However, such treatments were not as effective in carrot chips.

CONCLUSIONS

These new vegetable snacks could be a healthy alternative both at nutritional and toxicological level. In addition, acrylamide concentration could even be reduced with simple mitigation operations before frying. © 2018 Society of Chemical Industry.

The effects of baking conditions on acrylamide content in shortcrust cookies with added freeze-dried aqueous rosemary extract

The aim of the present study was to determine the effects of baking air humidity and dough supplementation with freeze-dried aqueous rosemary extract on acrylamide content in shortcrust cookies, as well as on their antioxidant properties and phenolic composition. Shortcrust cookies were baked at 170 °C in dry or humid (90%) air using 0.1, 0.2, or 0.5% of rosemary extract, and were compared to control samples without the extract. Acrylamide concentration in the obtained products ranged from 22.49 to 28.38 µg kg⁻¹. Furthermore, cookies baked in humid air had less acrylamide (by 6% on average) than those baked in dry air, irrespective of extract content. On the other hand, a significant relationship was found between humidity conditions and total phenolic content in the final products. Shortcrust cookies containing 0.5% of rosemary extract and baked in humid air revealed the best antioxidant properties as their total polyphenol content was approx. Three times higher than that in control samples. Furthermore, shortcrust cookies with 0.5% of rosemary extract showed superior DPPH radical scavenging capacity.

Enzyme Application for Reduction of Acrylamide Formation in Fried Potato Chips

Acrylamide is a carcinogenic compound formed in starchy food during heat processing. The application of L-asparaginase was found effective method to prevent acrylamide formation in fried potato chips. This enzyme efficiently catalyzes the conversion of amino acid L-asparagine into L-aspartic acid, which is not an acrylamide precursor. The acrylamide formation is considerably limited by the application of this enzyme in fried food products. The potato chips were prepared and treated with different concentrations of L-asparginase enzyme viz. 0.2 IU, 1.0 IU, 1.5 IU and 2.0 IU respectively. The treated chips along with the control sample were subjected to various physicochemical and sensory analysis in general and acryalmide content in particular. It was observed that the acrylamide formation was drastically reduced to 0.019 ppm in the chips treated with 2.0 IU enzyme concentration with better sensory quality characteristics as compared to untreated control chips in which acrylamide formation was 15.65 ppm.

Mitigation strategies of acrylamide, furans, heterocyclic amines and browning during the Maillard reaction in foods

The Maillard reaction (MR) occurs widely during food manufacture and storage, through controlled or uncontrolled pathways. Its consequences are ambiguous depending on the nature and processing of the food products. The MR is often used by food manufacturer to develop appealing aromas, colour or texture in food products (cereal based food, coffee, meat…). However, despite some positive aspects, the MR could decrease the nutritional value of food, generate potentially harmful compounds (e.g. acrylamide, furans, heterocyclic amines) or modify aroma or colour although it is not desired (milk, fruit juice). This paper presents a review of the different solutions available to control or moderate the MR in various food products from preventive to removal methods. A brief reminder of the role and influence of the MR on food quality and safety is also provided.

Acrylamide formation in vegetable oils and animal fats during heat treatment

The method of liquid chromatographic tandem mass spectrometry was utilized and modified to confirm and quantify acrylamide in heating cooking oil and animal fat. Heating asparagine with various cooking oils and animal fat at 180°C produced varying amounts of acrylamide. The acrylamide in the different cooking oils and animal fat using a constant amount of asparagine was measured. Cooking oils were also examined for peroxide, anisidine and iodine values (or oxidation values). A direct correlation was observed between oxidation values and acrylamide formation in different cooking oils. Significantly less acrylamide was produced in saturated animal fat than in unsaturated cooking oil, with 366ng/g in lard and 211ng/g in ghee versus 2447ng/g in soy oil, followed by palm olein with 1442ng/g.