Effect of natural antioxidants on kinetic behavior of acrylamide formation and elimination in low-moisture asparagine–glucose model system

Flavonoids mitigation of typical food thermal processing contaminants: Potential mechanisms and analytical strategies

Due to unique chemical structure, flavonoids are secondary metabolites with numerous biological activities. Thermal processing of food usually produces some chemical contaminants, which cause an adverse effect on food quality and nutrition. Therefore, it is vital to reduce these contaminants in food processing. In this study, current researches around the inhibitory effect of flavonoids on acrylamide, furans, α-dicarbonyl compounds and heterocyclic amines (HAs) were summarized. It has been shown that flavonoids inhibited the formation of these contaminants to varying degrees in chemical or food models. The mechanism was mainly associated with natural chemical structure and partly with antioxidant activity of flavonoids. Additionally, methods and tools of analyzing interactions between flavonoids and contaminants were discussed. In summary, this review demonstrated potential mechanisms and analytical strategies of flavonoids in food thermal processing, providing new insight of flavonoids applying on the food engineering.

Machine learning prediction of dual and dose-response effects of flavone carbon and oxygen glycosides on acrylamide formation

Introduction

The extensive occurrence of acrylamide in heat processing foods has continuously raised a potential health risk for the public in the recent 20 years. Machine learning emerging as a robust computational tool has been highlighted for predicting the generation and control of processing contaminants.

Methods

We used the least squares support vector regression (LS-SVR) as a machine learning approach to investigate the effects of flavone carbon and oxygen glycosides on acrylamide formation under a low moisture condition. Acrylamide was prepared through oven heating via a potato-based model with equimolar doses of asparagine and reducing sugars.

Results

Both inhibition and promotion effects were observed when the addition levels of flavonoids ranged 1–10,000 μmol/L. The formation of acrylamide could be effectively mitigated (37.6%–55.7%) when each kind of flavone carbon or oxygen glycoside (100 μmol/L) was added. The correlations between acrylamide content and trolox-equivalent antioxidant capacity (TEAC) within inhibitory range (R2 = 0.85) had an advantage over that within promotion range (R2 = 0.87) through multiple linear regression.

Discussion

Taking ΔTEAC as a variable, a LS-SVR model was optimized as a predictive tool to estimate acrylamide content (R2inhibition = 0.87 and R2promotion = 0.91), which is pertinent for predicting the formation and elimination of acrylamide in the presence of exogenous antioxidants including flavonoids.

Allicin Promoted Reducing Effect of Garlic Powder through Acrylamide Formation Stage

Background: Acrylamide is formed during food heating and is neurotoxic to animals and potentially carcinogenic to humans. It is important to reduce acrylamide content during food processing. Researchers have suggested that garlic powder could reduce acrylamide content, but the key substance and acrylamide reduction pathway of garlic powder was unclear. Methods: The inhibitory effect of garlic powder on acrylamide in asparagine/glucose solution and a fried potato model system were firstly evaluated. Furthermore, the effect of allicin on the amount of produced acrylamide in the asparagine/glucose solution model system and fried potatoes was studied with kinetic analysis. Results: The freeze-dried garlic powder had a higher inhibition rate (41.0%) than oven-dried garlic powder (maximum inhibition rate was 37.3%), and allicin had a 71.3% attribution to the reduction of acrylamide content. Moreover, the inhibition rate of allicin had a nonlinear relationship with the addition level increase. The kinetic analysis indicated that garlic powder and allicin could reduce acrylamide content through the AA formation stage, but not the decomposition stage. Conclusions: Allicin was the key component of garlic powder in reducing acrylamide content during acrylamide formation stage. This research could provide a new method to reduce acrylamide content during food processing and expand the application area of garlic.

Effects of Oral Administration of Bamboo (Dendrocalamus membranaceus) Leaf Flavonoids on the Antioxidant Capacity, Caecal Microbiota, and Serum Metabolome of Gallus gallus domesticus

The consumption of bamboo leaf flavonoids (BLFs) as novel dietary antioxidants has increased owing to their beneficial biological and pharmacological functions. This study assessed the in vivo effects of BLFs on antioxidant capacity, as well as caecal microbiota, serum metabolome, and health status. The Gallus gallus domesticus model and the oral administration approach were used with four treatment groups (basal diet, basal diet with 20 mg bacitracin/kg, basal diet with 50 mg BLF/kg, and basal diet with 250 mg BLF/kg). Ultra-high-performance liquid chromatography triple-quadrupole mass spectrometry analysis indicated that vitexin, fumaric acid, orientin, isoorientin, and p-coumaric acid were the predominant BLF components. From days 1 to 21, BLF increased the average daily gain and decreased the feed:gain of broilers. Moreover, BLF enhanced the serum antioxidant capacity and immune responses. Further, 16S rRNA sequencing showed that BLF modulated the caecal microbial community structure, which was dominated by Betaproteobacteriales, Erysipelatoclostridium, Parasutterella, Lewinella, Lactobacillus, and Candidatus Stoquefichus in BLF broilers. Among the 22 identified serum metabolites in BLF broilers, sphinganine, indole-3-acetaldehyde retinol, choline, 4-methylthio-2-oxobutanoic acid, and L-phenylalanine were recognised as biomarkers. In summary, BLFs appeared to modulate the caecal microbiome, alter the serum metabolome, and indirectly improve antioxidant capacity and health status.

Effect of the Addition of Soluble Dietary Fiber and Green Tea Polyphenols on Acrylamide Formation and In Vitro Starch Digestibility in Baked Starchy Matrices

Starch digestibility may be affected by food microstructural changes, as well as by specific interactions with some biomolecules, such as soluble dietary fibers (SDFs). It is well-known that acrylamide (AA) is a toxic and potentially carcinogenic compound formed in starchy food products processed at temperatures above 120 °C. This study aimed to investigate the effect of the addition of SDF and green tea polyphenols (GTP) on AA formation and in vitro starch digestibility in baked starchy matrices. The formulations were prepared using gluten and wheat starch, ensuring ~40 ± 2% (wet basis, w.b.) moisture in the doughs. In some samples, 7.5% (dry basis, d.b.) of starch was replaced with inulin (IN), polydextrose (PD) or partially hydrolyzed guar gum (PHGG), and/or with GTP at 1% (d.b). Acrylamide was determined by gas chromatography–mass spectrometry, and the in vitro starch digestibility using the Englyst method. The GTP was able to reduce AA content by ~48%, and a combination of IN-GTP allowed it to be reduced by up to ~64%, revealing the lowest rapidly available glucose content (~17 mg/g glucose). While a PD-GTP mixture reduced the AA content by around ~57% and gave the highest unavailable glucose fraction (~74 mg/g glucose) compared to the control. This study showed how functional ingredients could be used to develop successfully healthier starchy bakery foods.

Furan formation from ingredient interactions and furan mitigation by sugar alcohols and antioxidants of bamboo leaves in milk beverage model systems

BACKGROUND

Furan is a potential carcinogen that can be formed in various heat-treated foods, including milk beverages. Studies on the formation and mitigation of furan in milk beverages are rare. In the present study, the effects of ingredients on furan formation and the reduction of furan by sugar alcohols and antioxidants of bamboo leaves (AOB) were investigated in a milk beverage model system.

RESULTS

The results obtained demonstrated that the Maillard reaction is the major pathway for furan formation in a milk beverage model system, and the type of sugar has a great influence on furan formation. High fructose corn syrup (HFCS 55) was more favorable for furan formation than sucrose. Thermal oxidation of ascorbic acid and lipids significantly enhanced furan generation. Xylitol, sorbitol and mannitol inhibited furan formation in model systems by replacing sucrose or HFCS. The maximum inhibition percentage of furan formation was observed when sucrose/HFCS was substituted completely by xylitol and the inhibition rate was 78.28% and 88.64% separately for the sucrose/HFCS-containing system. AOB significantly inhibited furan formation and the inhibition rate reached 32.13% and 28.52% separately for the sucrose/HFCS-containing system.

CONCLUSION

The present study demonstrates that the use of sugar alcohols and AOB could be a feasible way of reducing furan formation in thermally processed milk beverages. © 2019 Society of Chemical Industry.

Modelling Contaminant Formation during Thermal Processing of Sea Buckthorn Purée

Background: The impact of thermal treatment on acrylamide (ACR) and hydroxymethylfurfural (HMF) formation was investigated for thermally treated sea buckthorn purée. Methods: An optimized procedure for minimizing ACR and HMF formation in thermally treated sea buckthorn purée was described. The precursors of ACR and HMF and their impact in heating of sea buckthorn purée to obtain jam-like products were also evaluated. Results: The contaminant content formed in samples was analyzed on thirteen running variants using a temperature range of 59.3-200.7 °C, and for heating durations between 5.9 and 34.1 min. The calculated equations of contaminant formation in sea buckthorn purée have established that the minimum content is formed at the lowest exposure time, between 10 and 20 min, for both ACR and HMF. The lowest ACR content was attained at 5.9-min exposure time and 130 °C temperature (0.3 µg/kg). For HMF the results revealed a lower quantity at 59.3 °C for 20-min exposure time (1.4 mg/kg). Conclusions: the found model is useful for the prediction of the best temperature/time conditions of the thermal treatment to obtain the lowest contaminates levels in the final product.

Acrylamide in daily food in the metropolitan area of Hanoi, Vietnam

Acrylamide, a colourless and odourless crystalline solid, formed via the Maillard reaction in food, has been reported with harmful properties for humans, such as toxicity and carcinogenicity. Three hundred and four processed food samples from 17 product types, collected in Hanoi, Vietnam, were analyzed by LC-MS/MS to measure the acrylamide concentration. The limit of detection (LOD) and the limit of quantification (LOQ) of acrylamide were 1 µg Kg^-1 and 3 µg Kg^-1, respectively. Effectively, the highest acrylamide content is usually found in processed food, which is one of the primary reasons of increased acrylamide content in food. All French fried samples contained acrylamide above 500 µg kg^-1. Acrylamide concentration in non-fried noodle, vermicelli, rice noodle, phở, dried vegetable, and rice cracker is lower than in potato chips, fried potatoes, fried cake, and fried noodles. The results could be helpful to estimate exposure and risk assessment of acrylamide in Vietnam.

Epicatechin Adducting with 5-Hydroxymethylfurfural as an Inhibitory Mechanism against Acrylamide Formation in Maillard Reactions

This study aimed to investigate the inhibitory mechanism of epicatechin (EC) on the formation of acrylamide in Maillard reactions. The glucose + asparagine model is a typical chemical system used to investigate acrylamide formation. 5-Hydroxymethylfurfural (HMF) is an important carbonyl intermediate in Maillard reactions and can also react with asparagine to form acrylamide. Time courses showed that EC inhibited more HMF than acrylamide in the glucose + asparagine model heated at 180 °C. The reduction of EC on acrylamide formation in the HMF + asparagine model was about 70%, while that in the glucose + asparagine model was about 50%. Moreover, HMF decreased significantly faster when it was heated in the presence of EC. Liquid chromatography-mass spectrometry analysis revealed the formation of adducts between EC and HMF, and the dimeric adducts were verified in fried potato chips. These results suggested that the condensation of EC and HMF was one of the key steps leading to the inhibition of acrylamide. UV-visible spectra analysis showed that some polymerization products had absorption in the visible region and contributed to the development of browning, which was underestimated in the past.

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.

Inhibitory effects of Japanese horseradish (Wasabia japonica) on the formation and genotoxicity of a potent carcinogen, acrylamide

BACKGROUND

The formation of acrylamide (AA) in cooked foods has raised human health concerns. AA is metabolized by cytochrome P450 2E1 (CYP2E1) to glycidamide (GA), which forms DNA adducts. This study examined the inhibitory effects of wasabi (Japanese horseradish, Wasabia japonica) roots and leaves as well as their active component, allyl isothiocyanate (AIT), on the formation and genotoxicity of AA.

RESULTS

AA formation (51.8 ± 4.2 µg kg^-1 ) was inhibited with ≥2 mg mL^-1 of AIT. Wasabi roots also inhibited AA formation (∼90% reduction), but wasabi leaves were not effective at 2 mg mL^-1 . Wasabi roots and leaves decreased the number of cells with micronuclei by approximately 33 and 24% respectively compared with the AA treatment group. Moreover, wasabi roots and leaves (100 mg kg^-1 body weight (BW) day^-1 for each) decreased AA (100 mg kg^-1 BW day^-1 )-induced DNA damage. The AA-induced CYP2E1 activity was decreased by 39 and 26% with wasabi roots and leaves respectively. Further, the activity of glutathione S-transferase, which catalyzes the detoxification of AA via glutathione conjugation, increased by 54 and 33% with wasabi roots and leaves respectively.

CONCLUSION

These results indicate that wasabi roots and leaves are effective ingredients for inhibiting the formation and genotoxicity of AA. © 2016 Society of Chemical Industry.

A combination of additives can synergically decrease acrylamide content in gingerbread without compromising sensory quality

BACKGROUND

The present study tested whether replacement of the leavening agent ammonium carbonate by sodium hydrogen carbonate in combination with calcium cation and acidifying agent will synergically decrease acrylamide (AA) content in gingerbread.

RESULTS

The type of leavening agent and the presence of Ca²⁺ and citric acid accounted for 33.6%, 13.2% and 53.2% of the explained variability of the AA content, respectively (P < 0.01). The AA content in gingerbread produced with (NH₄ )₂ CO₃ alone was 186.5 µg kg^-1 . Irrespective of other tested additives, NaHCO₃ decreased (P < 0.05) AA content to 42% compared to (NH₄ )₂ CO₃ . Combination of NaHCO₃ + CaCl₂ + citric acid in dough reduced (P < 0.05) AA content below the limit of detection (25 µg kg^-1 ). The AA content in gingerbread (y; µg kg^-1 ) decreased with an increasing number of additives used (x) according to the equation y = 158.8 - 47.94x (r² = 0.42; P < 0.0001). A comprehensive sensory analysis did not indicate any significant deterioration (P > 0.05) in the organoleptic quality of gingerbread produced using calcium cation and citric acid.

CONCLUSION

The present study demonstrates that the combination of additives NaHCO₃ /Ca²⁺ /citric acid synergically decreases AA content in gingerbread without compromising the sensory quality. © 2016 Society of Chemical Industry.

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.

Support vector regression-guided unravelling: antioxidant capacity and quantitative structure-activity relationship predict reduction and promotion effects of flavonoids on acrylamide formation

We used the support vector regression (SVR) approach to predict and unravel reduction/promotion effect of characteristic flavonoids on the acrylamide formation under a low-moisture Maillard reaction system. Results demonstrated the reduction/promotion effects by flavonoids at addition levels of 1–10000 μmol/L. The maximal inhibition rates (51.7%, 68.8% and 26.1%) and promote rates (57.7%, 178.8% and 27.5%) caused by flavones, flavonols and isoflavones were observed at addition levels of 100 μmol/L and 10000 μmol/L, respectively. The reduction/promotion effects were closely related to the change of trolox equivalent antioxidant capacity (ΔTEAC) and well predicted by triple ΔTEAC measurements via SVR models (R: 0.633–0.900). Flavonols exhibit stronger effects on the acrylamide formation than flavones and isoflavones as well as their O-glycosides derivatives, which may be attributed to the number and position of phenolic and 3-enolic hydroxyls. The reduction/promotion effects were well predicted by using optimized quantitative structure-activity relationship (QSAR) descriptors and SVR models (R: 0.926–0.994). Compared to artificial neural network and multi-linear regression models, SVR models exhibited better fitting performance for both TEAC-dependent and QSAR descriptor-dependent predicting work. These observations demonstrated that the SVR models are competent for predicting our understanding on the future use of natural antioxidants for decreasing the acrylamide formation.

Effect of garlic powder on acrylamide formation in a low-moisture model system and bread baking

BACKGROUND

Acrylamide (AA) is of concern worldwide because of its neurotoxicity, genotoxicity and reproductive/developmental toxicity. Consequently, methods for minimizing AA formation during food processing are vital.

RESULTS

In this study, the formation and elimination of AA in an asparagine/glucose low-moisture model system were investigated by response surface methodology. The effect of garlic powder on the kinetics of AA formation/elimination was also evaluated. The AA content reached a maximum level (674.0 nmol) with 1.2 mmol of glucose and 1.2 mmol of asparagine after heating at 200 °C for 6 min. The AA content was greatly reduced with the addition of garlic powder. Compared to without garlic powder, an AA reduction rate of 43% was obtained with addition of garlic powder at a mass fraction of 0.05 g. Garlic powder inhibited AA formation during the generation-predominant kinetic stage and had no effect on the degradation-predominant kinetic stage. The effect of garlic powder on AA formation in bread and bread quality was also investigated. Adding a garlic powder mass fraction of 15 g to 500 g of dough significantly (P < 0.05) reduced the formation of AA (reduction rate of 46%) and had no obvious effect on the sensory qualities of the bread.

CONCLUSION

This study provides a possible method for reducing the AA content in bread and other heat-treated starch-rich foods.

Acylation of Antioxidant of Bamboo Leaves with Fatty Acids by Lipase and the Acylated Derivatives' Efficiency in the Inhibition of Acrylamide Formation in Fried Potato Crisps

This study selectively acylated the primary hydroxyl groups on flavonoids in antioxidant of bamboo leaves (AOB) using lauric acid with Candida antarctica lipase B in tert-amyl-alcohol. The separation and isolation of acylated derivatives were performed using silica gel column chromatography with a mixture of dichloromethane/diethyl ether/methanol as eluents. Both thin layer chromatography and high-performance liquid chromatography analyses confirmed the high efficiency of the isolation process with the purified orientin-6″-laurate, isoorientin-6″-laurate, vitexin-6″-laurate, and isovitexin-6″-laurate that were obtained. The addition of AOB and acylated AOB reduced acrylamide formation in fried potato crisps. Results showed that 0.05% AOB and 0.05% and 0.1% acylated AOB groups significantly (p < 0.05) reduced the content of acrylamide in potato crisps by 30.7%, 44.5%, and 46.9%, respectively.

Role of antioxidants and phytochemicals on acrylamide mitigation from food and reducing its toxicity

Nowadays, the presence of acrylamide in lots of fried and baked foods raises concerns due to its potential to cause toxicity and cancer in animals and human. Consequently, a number of papers have focused on evaluation of various chemicals in reduction of acrylamide in various food sources, as well as decreasing its related toxicities. In addition, plants are important sources of diverse metabolites demonstrating either possible effectiveness in acrylamide toxicity or reduction of acrylamide content in food sources. In this paper, we have criticized all relevant studies in terms of acrylamide mitigation from food by phytochemicals and antioxidants, and the influence of herbal medicines and phyto-pharmaceuticals on reduction of acrylamide toxicity in both animals and human.

A critical review on properties and applications of microbial l-asparaginases

l-Asparaginase is one of the main drugs used in the treatment of acute lymphoblastic leukemia (ALL), a commonly diagnosed pediatric cancer. Although several microorganisms are found to produce l-asparaginase, only the purified enzymes from E. coli and Erwinia chrysanthemi are employed in the clinical and therapeutic applications in humans. However, their therapeutic response seldom occurs without some evidence of hypersensitivity and other toxic side effects. l-Asparaginase is also of prospective use in food industry to reduce the formation of acrylamide in fried, roasted or baked food products. This review is an attempt to compile information on the properties of l-asparaginases obtained from different microorganisms. The complications involved with the therapeutic use of the currently available l-asparaginases, and the enzyme's potential application as a food processing aid to mitigate acrylamide formation have also been reviewed. Further, avenues for searching alternate sources of l-asparaginase have been discussed, highlighting the prospects of endophytic microorganisms as a possible source of l-asparaginases with varied biochemical and pharmacological properties.

Unravelling the effect of flavonoids on the kinetic profiles of acrylamide in the Maillard reaction

Flavonoids play a positive role in the fructose-participating Maillard reaction and significantly reduce the formation of acrylamide during the advanced reaction stage but not affect its elimination process.

Effects of antioxidants of bamboo leaves and flavonoids on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) formation in chemical model systems

The inhibitory effects of antioxidants of bamboo leaves (AOB) and flavonoids against 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) formation were investigated in creatinine and phenylalanine model systems. AOB and the tested flavonoids (orientin, homoorientin, vitexin, isovitex, apigenin, luteolin, isorhamnetin, fisetin, and hesperetin) had significant dose-dependent inhibition effects on PhIP formation with different IC50 values. The superoxide anion (O2(•-)) scavenging activities of these nine flavonoids were evaluated using the pyrogallol autoxidation system. The EC50 values of compounds that showed antioxidant activity were found to correlate well (R(2) = 0.8003) with the corresponding IC50 values representing their inhibition of PhIP formation. It was assumed that the inhibitory effects of flavonoids on PhIP formation were probably achieved by scavenging free radicals generated in the reaction system. These findings provide valuable information for the development of effective strategies to minimize heterocyclic amine content in thermally processed food.

Risk assessment, formation, and mitigation of dietary acrylamide: current status and future prospects

Acrylamide (AA) was firstly detected in food in 2002, and since then, studies on AA analysis, occurrence, formation, toxicity, risk assessment and mitigation have been extensively carried out, which have greatly advanced understanding of this particular biohazard at both academic and industrial levels. There is considerable variation in the levels of AA in different foods and different brands of the same food; therefore, so far, a general upper limit for AA in food is not available. In addition, the link of dietary AA to human cancer is still under debate, although AA has been known as a potential cause of various toxic effects including carcinogenic effects in experimental animals. Furthermore, the oxidized metabolite of AA, glycidamide (GA), is more toxic than AA. Both AA and GA can form adducts with protein, DNA, and hemoglobin, and some of those adducts can serve as biomarkers for AA exposure; their potential roles in the linking of AA to human cancer, reproductive defects or other diseases, however, are unclear. This review addresses the state-of-the-art understanding of AA, focusing on risk assessment, mechanism of formation and strategies of mitigation in foods. The potential application of omics to AA risk assessment is also discussed.

Chlorogenic acid increased acrylamide formation through promotion of HMF formation and 3-aminopropionamide deamination

This research was aimed to investigate why chlorogenic acid, presents at high concentrations in some food raw material, influences acrylamide formation. In the asparagine/glucose Maillard reaction system (pH=6.8), addition of chlorogenic acid significantly increased acrylamide formation and inhibited its elimination. In contrast, the quinone derivative of chlorogenic acid decreased acrylamide formation. Three mechanisms may be involved for increasing acrylamide formation by chlorogenic acid. Firstly, it increased the formation of HMF, which acts as a more efficient precursor than glucose to form acrylamide. Secondly, it decreased activation energy for conversion of 3-aminopropionamide (3-APA) to acrylamide (from 173.2 to 136.6kJ/mol), and enhances deamination from 3-APA. And thirdly, it prevented attack of the produced acrylamide from free radicals by keeping high redox potential during the Maillard reaction.

Effects of certain polyphenols and extracts on furans and acrylamide formation in model system, and total furans during storage

Using a glucose-glycine and asparagine-fructose system as a Maillard reaction model, the effects of seven polyphenols and solid phase extracts of three plants on the formation of furans and acrylamide were investigated. The polyphenols and extracts were used in biscuit formulation and acrylamide formation was observed. They were used for the storage of the glycine-glucose model system at three different temperatures. The addition of some of the extracts and polyphenols significantly decreased furan formation to different extents. All phenolic compounds and plant extracts decreased in the range of 30.8-85% in the model system except for oleuropein, and all of them decreased in the range of 10.3-19.2% in biscuit. Total furan formation was inhibited by caffeic acid, punicalagin, epicatechin, ECE and PPE during storage. This study evaluated and found the inhibitory effect on the formation of furans and acrylamide in Maillard reactions by the use of some plant extracts and polyphenols.

Role of curcumin in the conversion of asparagine into acrylamide during heating

This study aimed to investigate the ability of curcumin to convert asparagine into acrylamide during heating at different temperatures. Binary and ternary model systems of asparagine-curcumin and asparagine-curcumin-fructose were used to determine the role of curcumin on acrylamide formation in competitive and uncompetitive reaction conditions. The results indicated that curcumin could potentially contribute to acrylamide formation under long-term heating conditions as long as asparagine was present in the medium. The amount of acrylamide formed in the ternary system was slightly higher than in the binary system during heating (p < 0.05), because of the higher concentrations of carbonyl compounds initially available. The kinetic trends were similar in both model systems evidencing that fructose reacted with asparagine more rapidly than curcumin. The data reveal that acrylamide formation in the temperature range of 150-200°C obeys Arrhenius law with activation energy of 79.1 kJ/mole. Data of this work showed the possibility that antioxidants having a carbonyl compound can react directly with ASN leading to acrylamide. The addition of antioxidants to foods may increase the formation of acrylamide upon long-term heating if free sugar concentration is low and ASN concentration is relatively high.

Dietary plant materials reduce acrylamide formation in cookie and starch-based model systems

BACKGROUND

Dietary plant materials have attracted much attention because of their health benefits to humans. Acrylamide is found in various heated carbohydrate-rich foods. Our previous results showed that crude aqueous extracts from diverse dietary plants and some phenolic compounds could mitigate acrylamide formation in an asparagine-glucose model system. Based on our previous study, several plant materials were selected to further investigate their inhibitory effects on acrylamide formation in cookies and starch-based model systems.

RESULTS

Addition of raw powders from selected dietary plants and their crude aqueous extracts could considerably reduce acrylamide formation in both cookie and potato starch-based models. Aqueous extracts of clove at 4% caused the largest reduction (50.9%) of acrylamide in cookies, whereas addition of 2% proanthocyanidins from grape seeds gave the greatest acrylamide reduction (62.2%) in a starch-based model system.

CONCLUSION

It may be feasible to use some of the tested dietary plant materials to reduce acrylamide formation in cookies and other starchy foods.

New trends in quantification of acrylamide in food products

Methods applied in acrylamide quantification in foods have been reviewed in this paper. Novel analytical techniques like capillary electrophoresis (CE), immunoenzymatic test (ELISA) and electrochemical biosensors, which can replace traditional methods like high performance liquid chromatography (HPLC) and gas chromatography (GC) were presented. Short time of analysis and high resolution power of electrophoretic techniques caused that they became routinely used in food analysis apart from high performance liquid chromatography and gas chromatography. Application of modern chromatography methods like ultra performance liquid chromatography (UPLC) in acrylamide quantification considerably shortened the time of analysis and decreased the consumption of indispensable reagents. The most promising approaches to acrylamide quantification in foods are electrochemical biosensors and immunoenzymatic tests. In contrast to chromatography and electrophoretic methods they require neither expensive equipment nor time consuming sample preparation and allow for fast screening of numerous samples without the usage of sophisticated apparatuses. Because of many advantages such as miniaturization, rapid and simple analysis, and high sensitivity and selectivity, biosensors are thought to replace conventional methods of acrylamide quantification in food.

Effect of antioxidants on elimination and formation of acrylamide in model reaction systems

Antioxidants, including tert-butyl hydroquinone (TBHQ), butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), ferulic acid, epigallocatechin gallate (EGCG) and vitamin C (V(C)), and their corresponding oxidation products, were tested for their influence on elimination of acrylamide and inhibition of acrylamide formation. Our experimental results showed that the antioxidants could neither effectively destruct acrylamide nor inhibit (or even promote) its formation, but their corresponding oxidation products were able to directly destruct acrylamide and its precursor, asparagine, thus inhibit acrylamide formation. Moreover, a positive correlation between the carbonyl value and acrylamide formation was observed in a frying oil-asparagine reaction model system, suggesting that antioxidants can inhibit acrylamide formation by inhibiting oil carbonyl compounds formation.

Inhibitory mechanism of naringenin against carcinogenic acrylamide formation and nonenzymatic browning in Maillard model reactions

Chemical model reactions were carried out to investigate the effect of a citrus flavonoid, naringenin, on the formation of acrylamide under mild heating conditions. Results showed that naringenin significantly and dose dependently inhibited the formation of acrylamide (20-50% relative to the control), although not in a linear manner. Moreover, the presence of naringenin in acrylamide-producing models effectively reduced the extent of browning. Careful comparison of the HPLC chromatograms of samples from the chemical model reactions revealed that naringenin likely reacted with Maillard intermediates, giving rise to new derivatives. Subsequent LC-MS analyses suggested that the proposed derivatives have a predicted molecular mass of 341 Da. Eventually, two derivatives were purified and characterized with LC-MS/MS and NMR spectroscopy as 8-C-(E-propenamide)naringenin and 6-C-(E-propenamide)naringenin, respectively. In other words, naringenin, a rather weak antioxidant, strongly inhibited acrylamide formation probably by directly reacting with acrylamide precursors, thus diverting them from the pathways that lead to acrylamide formation.

Effects of fruit extracts on the formation of acrylamide in model reactions and fried potato crisps

Natural products extracted from plants and fruits have attracted increasing attention for the development of effective inhibitors against the formation of acrylamide during food processing. In this study, six fruit extracts (apple, blueberry, mangosteen, longan, dragon fruit with white flesh, and dragon fruit with red flesh) were compared for their activities against acrylamide formation in chemical models containing equal molar quantities of glucose and asparagine in distilled water (160 degrees C for 30 min). Apple extract demonstrated potent inhibition on acrylamide formation. Blueberry, mangosteen, and longan extracts did not have significant impact, whereas dragon fruit extracts enhanced acrylamide formation. Column chromatography guided by chemical model analysis showed that the proanthocyanidin-rich subfraction played a key role in mediating the inhibitory activity. The inhibitory activity was finally corroborated in fried potato crisps. The present study identified some natural products that might have important applications in the food industry to inhibit acrylamide formation.