Inhibition Of Acrylamide Formation Research Articles

Comparative effects of pectin and hydrolyzed pectin coating as pre-frying treatments on acrylamide formation in potato chips

This study aimed to compare the effects of pectin and hydrolyzed pectin coating as pre-frying treatments on acrylamide content and quality characteristics of fried potato chips. The hydrolyzed pectin with molecular weight (Mw) of 8.81 ± 0.49 kDa was obtained through partial degradation of pectin (Mw: 747.57 ± 6.73 kDa) using pectinase. Results showed that both pectin and hydrolyzed pectin coating significantly inhibited acrylamide formation and inhibition rates exceeded 90 %. Hydrolyzed pectin had stronger inhibitory activity against acrylamide formation than pectin, especially when the concentration of hydrolyzed pectin was >2 %, its inhibitory rate exceeded 95 %. Compared to pectin coating, hydrolyzed pectin coating endow fried potato chips with smaller browning, higher crispness, less moisture but higher oil content. Overall, hydrolyzed pectin had better application prospects than pectin in inhibiting acrylamide formation of fried potato chips.

Construction of L-Asparaginase Stable Mutation for the Application in Food Acrylamide Mitigation

Acrylamide, a II A carcinogen, widely exists in fried and baked foods. L-asparaginase can inhibit acrylamide formation in foods, and enzymatic stability is the key to its application. In this study, the Escherichia coli L-asparaginase (ECA) stable variant, D60W/L211R/L310R, was obtained with molecular dynamics (MD) simulation, saturation mutation, and combinatorial mutation, the half-life of which increased to 110 min from 60 min at 50 °C. Furthermore, the working temperature (maintaining the activity above 80%) of mutation expanded from 31 °C–43 °C to 35 °C–55 °C, and the relative activity of mutation increased to 82% from 65% at a pH range of 6–10. On treating 60 U/mL and 100 U/g flour L-asparaginase stable mutant (D60W/L211R/L310R) under uncontrolled temperature and pH, the acrylamide content of potato chips and bread was reduced by 66.9% and 51.7%, which was 27% and 49.9% higher than that of the wild type, respectively. These results demonstrated that the mutation could be of great potential to reduce food acrylamide formation in practical applications.

Inhibition of acrylamide formation in potato strip by ultrasonic‐treated methylcellulose batter

SUMMARYThe ultrasonic (US)‐treated batter mixtures of commercial methylcellulose (MC) as the fried potato strips' coating layer were demonstrated. The layer formed a rapid gel that absorbs the substrate's water content and related functional groups that contribute to acrylamide formation reduction. Different concentrations of MC (0.5‐2.0 w/v %) mixtures were subjected to US at 20 W to evaluate coating layers' effect prior to the deep‐frying process. At 1% w/v concentration batter mixture, the USMC layer reduced the highest acrylamide value. For comparison purposes, the differences in the acrylamide content of the USMC, the non‐USMC and the uncoated samples were 64.7 ± 5.04, 156.4 ± 7.44 and 344.1 ± 5.39 ng g‐1, respectively. The results were supported with lower oil uptake and water retention of the USMC compared with the non‐USMC with the values of 2.2 g/100g and 28.6 g/100g with 5.1 g/100g and 47 g/100g, respectively.

Acrylamide mitigation using zein–polysaccharide complex particles

Protein–polysaccharide biopolymer particles composed of potential acrylamide inhibitors, including zein, chitosan, alginate, and pectin, were used for acrylamide mitigation in this study. The synergistic effect of zein and polysaccharides in complex particles was hypothesized to inhibit acrylamide formation at high temperature. A reaction model utilizing a glucose and asparagine solution heated at 170 °C for 30 min in a heating block was implemented. Zein, zein–polysaccharide complex particles, and a mixture of zein and polysaccharides (non-complex particles) were used as acrylamide inhibitor solutions. The highest acrylamide reduction was observed at a zein concentration of 0.67% (w/v). Because glutamine and asparagine are the major amino acids found in zein, higher zein concentration (>1%, w/v) increased acrylamide formation. An increase in charge or stability was noted after particle formation, such as zein–sodium alginate (−49.07 to −57.20 mV) and zein–pectin (−27.80 to −31.57 mV), coupled with an increase in average size. Zein–polysaccharide complex particles successfully reduced acrylamide concentration in a heating block model. The most effective acrylamide inhibitor was zein–alginate (1:0.50). However, zein–chitosan particles exerted the opposite effect, thereby promoting acrylamide formation. The acrylamide content in fried potato strips dipped in complex particles (11.07–13.22 μg/mL) was lower than that observed in control (16.08 μg/mL). The interfacial rheology of sticky adsorbing particles with food surfaces requires further investigation.

Inhibitory effect of polysaccharides on acrylamide formation in chemical and food model systems

The inhibitory effect of three polysaccharides (alginate, pectin and chitosan) on acrylamide formation was investigated in chemical and fried potato food model systems, under two heating regimes (heating block and microwave). In the chemical system, acrylamide formation followed a second order reaction kinetic behaviour. Activation energies (Ea) were 17.85 and 110.78 kJ/mol for conventional and microwave heating respectively. Acrylamide content was highest at 180 °C after 60 min conventional heating (27.88 ng/ml) and 3.5 fold higher after microwave heating for 60 s (800 W, 98.02 ng/ml). Alginate (0.3% w/v) and pectin (0.2% w/v) solutions efficiently inhibited acrylamide formation by 65% and 56% respectively under conventional heating, and 36% and 30% respectively under microwave heating. Coating potatoes with alginate, pectin and chitosan (1% w/v) prior to frying dramatically inhibited acrylamide formation by 54%, 51% and 41% respectively. However only alginate and pectin slightly reduced acrylamide by 5% in the microwave.

Simultaneous inhibition of acrylamide formation and fat oxidation in quinoa cakes using gum Arabic supplementation coupled with fat reduction

ABSTRACT The current work aimed to study the effect of adding gum Arabic and varying fat (butter) contents on the physicochemical characteristics of gluten-free quinoa cakes and compared it to cakes made from 100% wheat flour and control quinoa flour. Gum Arabic (GA) was supplemented in three levels (0.1, 0.5, and 1%, w/w) while fat was simultaneously reduced at 25, 50, and 75% (w/v) during the preparation of 100% gluten-free quinoa cakes (GFQCs). A coupling effect of 1% GA and 50% lower fat was successfully applied to inhibit AA up to 83%, fat oxidation up to 64%, and browning intensity up to 59.1% without impairing the baking performance. Moreover, supplementation of 1% GA produced softer and lighter QFQCs, which was similar to 100% wheat cakes. The odor intensity detected by electronic nose technique was also lowered in QFQCs. Consequently, the current work serves the worldwide demand for gluten-free bakery products having healthier profile with low fat oxidation and AA formation.

Metagenomic discovery and functional validation of L-asparaginases with anti-leukemic effect from the Caspian Sea.

SummaryBy screening 27,000 publicly available prokaryotic genomes, we recovered ca. 6300 type I and ca. 5200 type II putative L-asparaginase highlighting the vast potential of prokaryotes. Caspian water with similar salt composition to the human serum was targeted for in silico L-asparaginase screening. We screened ca. three million predicted genes of its assembled metagenomes that resulted in annotation of 87 putative L-asparaginase genes. The L-asparagine hydrolysis was experimentally confirmed by synthesizing and cloning three selected genes in E. coli. Catalytic parameters of the purified enzymes were determined to be among the most desirable reported values. Two recombinant enzymes represented remarkable anti-proliferative activity (IC50 <1IU/ml) against leukemia cell line Jurkat while no cytotoxic effect on human erythrocytes or human umbilical vein endothelial cells was detected. Similar salinity and ionic concentration of the Caspian water to the human serum highlights the potential of secretory L-asparaginases recovered from these metagenomes as potential treatment agents.

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

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. 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. 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.

Characterization of a novel type I l-asparaginase from Acinetobacter soli and its ability to inhibit acrylamide formation in potato chips

l-Asparaginases have the potential to inhibit the formation of acrylamide, a harmful toxin formed during high temperature processing of food. A novel bacterium which produces l-asparaginase was screened. Type I l-asparaginase gene from Acinetobacter soli was cloned and expressed in Escherichia coli. The recombinant l-asparaginase had an activity of 42.0 IU mL-1 and showed no activity toward l-glutamine and d-asparagine. The recombinant l-asparaginase exhibited maximum catalytic activity at pH 8.0 and 40°C. The enzyme was stable in the pH ranging from 6.0 to 9.0. The activity of the recombinant enzyme was substantially enhanced by Ba2+, dithiothreitol, and β-mercaptoethanol. The Km and Vmax values of the l-asparaginase for the l-asparagine were 3.22mmolL-1 and 1.55 IU μg-1, respectively. Moreover, the recombinant l-asparaginase had the ability to mitigate acrylamide formation in potato chips. Compared with the untreated group, the content of acrylamide in samples treated with the enzyme was effectively decreased by 55.9%. These results indicate that the novel type I l-asparaginase has the potential for application in the food processing industry.

Efficient inhibition of acrylamide formation in French fries by dipping in lactic acid solution before and after par-frying in a two-step procedure

Efficient inhibition of acrylamide formation in French fries by dipping in lactic acid solution before and after par-frying in a two-step procedure

Usefulness of barley flour for retention of palatability and antioxidant capacity and inhibition of acrylamide formation in flour products cooked at high temperatures

Acrylamide (AAm) is a harmful substance generated during a Maillard reaction between asparagine and a reducing sugar, when food is cooked at high temperatures. However, this type of cooking increases the amounts of antioxidants and the fragrant aroma and coloration that make food tasty. In this study, with the aim to determine whether AAm formation could be reduced while palatability and antioxidant capacity were retained, doughnuts were made from milled grains with limited asparagine content. Frying doughnuts made from wheat flour for a longer period significantly increased antioxidant capacity and the amount of AAm generated. Frying doughnuts made from barley-blended flour with limited asparagine content for long periods significantly increased their antioxidant capacity and decreased the amount of AAm generated by 72%. The 28-person evaluation panel deemed them as good as the doughnuts made from wheat flour. Making doughnuts from barley-blended flour can increase their antioxidant capacity while retaining palatability and reducing the amount of harmful AAm in food.

Effect of Fat-Soluble Anti-oxidants in Vegetable Oils on Acrylamide Concentrations During Deep-Fat Frying of French Fries.

BackgroundThis study attempted to evaluate the effect of fat-soluble anti-oxidants in vegetable oils on acrylamide during the deep-fat frying of French fries.MethodsThree vegetable oils with different fat-soluble anti-oxidant contents were selected and par-fried potato strips were fried in these oils. Acrylamide in the French fries at different frying times (at 180 °C) and over 10 consecutive frying sessions were measured. The anti-oxidant contents and quality degradation of oils were monitored before and after the 5th and 10th consecutive frying sessions.ResultsThe effect of the fat-soluble anti-oxidants in red palm oil on the acrylamide was more apparent when a prolonged frying time was used for consecutive frying sessions than when different frying conditions were used. Using red palm oil, acrylamide concentration in French fries significantly dropped to the lowest level, at 524 ng g−1, after the 10th frying session. The β-carotene content after the 10th frying session was the highest in red palm oil.ConclusionThe use of red palm oil for deep-fat frying French fries can be a mitigation strategy to reduce acrylamide formation, but further studies are necessary to investigate the influence of different types of fat-soluble anti-oxidants on the inhibition of acrylamide formation.

A new pH indicator dye-based method for rapid and efficient screening of l -asparaginase producing microorganisms

l-asparaginase is a pharmaceutically and industrially important enzyme as it has potential to treat different cancers and inhibit acrylamide formation in fried and baked food products. In the present study, an attempt was made to screen for new and novel l-asparaginase producers using a widely applied phenol red and bromothymol blue (BTB)1 dye-based plate assay. Screening of four different soil samples for l-asparaginase producers resulted in the isolation of three new potential l-asparaginase producing bacteria. These three strains identified (by 16S rRNA sequencing) as a Pseudomonas resinovorans strain IGS-131, a Bacillus safensis strain IGS-81, and a Glutamicibacter arilaitensis strain ICS-13 with enzyme activities of 10.91 IU/ml, 6.65 IU/ml, and 1.47 IU/ml, respectively. These three strains of bacteria have not been reported as l-asparaginase producers previously. Also, we developed a new pH indicator dye-based plate assay for the screening of l-asparaginase producers after testing eight different pH indicator dyes. This cresol red dye-based method gave a better differentiable zone of hydrolysis and consistent results as compared to previously reported phenol red and BTB-based plate assay. It was also found to be efficient in comparison to all other dyes studied. It produced a bright yellow color at acidic pH (5.5) and turned into a dark red or maroon color when pH was increased (above 7.5). This finding is expected to make screening of all kinds of l-asparaginases more comfortable, rapid, and efficient.

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

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

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.

Cysteine alone or in combination with glycine simultaneously reduced the contents of acrylamide and hydroxymethylfurfural

Inhibition of acrylamide formation in food has been extensively reported, but some mitigation methods result in a concomitant increase in hydroxymethylfurfural (HMF), a food contaminant mainly produced through Maillard reaction. Mitigation strategies to reduce HMF are not yet available. This study showed that cysteine alone or in combination with glycine could simultaneously and significantly reduce the content of acrylamide and HMF in asparagine/glucose model as well as in biscuits. Mixing 0.36 g/100 g of cysteine and 0.2 g/100 g (w/w) of glycine into the dough reduced 97.8% and 93.2% of acrylamide and HMF, respectively, in biscuits. Cysteine reduced HMF content possibly by reacting with formed HMF through Michael adduction and Maillard reaction.

Role of plant polyphenols in acrylamide formation and elimination

Acrylamide found in thermal-treated foods has led to an intensive and persistent research effort, since it is a neurotoxic, genotoxic and probable carcinogenic compound to humans. Plant polyphenols are the most abundant antioxidants in human diet. Several researches indicated that the polyphenols affected the acrylamide formation during heating. However, the controversial effects of the polyphenols on acrylamide formation were related to their structure, concentrations, and antioxidant capacity, as well as reaction condition. Polyphenols can inhibit acrylamide formation through trapping of carbonyl compounds and preventing against lipid oxidation, while some special polyphenols can enhance the acrylamide content by providing carbonyl groups, accelerating the conversion from 3-aminopropionamide (3-APA) to acrylamide and inhibiting acrylamide elimination. This review concludes the effects of polyphenols in the Maillard reaction and food systems conducted so far, aimed to give an overview on the role of plant polyphenols in acrylamide formation and elimination.

Recent research progress on microbial L-asparaginases.

L-Asparaginases (EC 3.5.1.1) are enzymes that catalyze the hydrolysis of L-asparagine to L-aspartic acid and found in a variety of organisms from microorganisms to mammals. However, they are mainly expressed and produced by microorganisms. Microbial L-asparaginases have received sustained attention due to their irreplaceable role in the therapy of acute lymphoblastic leukemia and for their inhibition of acrylamide formation during food processing. In this article, we review the application of microbial L-asparaginases in medical treatments and acrylamide mitigation. In addition, we describe in detail recent advances in the existing sources, purification, production, properties, molecular modification, and immobilization of L-asparaginase.

Effect of ascorbic acid on the properties of ammonia caramel colorant additives and acrylamide formation.

Ammonia caramels are among the most widely used colorant additives in the food industry. They are commonly prepared through the Maillard reaction and caramelization of mixtures of reducing sugars with ammonia or ammonium salts. Antioxidants are known to inhibit acrylamide formation during the Maillard reaction, and they may affect the properties of the ammonia caramel products. Thus, the objective of this study was to investigate the effect of the antioxidant ascorbic acid on the properties of ammonia caramel. A mixture of glucose and ammonia was allowed to react at 120 °C for 60 min in the presence of ascorbic acid at final concentrations of 0 to 0.08 M. The ammonia caramels obtained from these reactions were all positively charged. As the concentration of ascorbic acid increased, the color intensity of the ammonia caramel showed a decreasing trend, while the intensity of the fluorescence and total amount of pyrazines in the volatiles showed a tendency to increase. The addition of ascorbic acid did not result in obvious changes in the UV-visible spectra of the ammonia caramels and the types of pyrazines in the volatiles were also unchanged. It is noteworthy that the addition of 0.02 to 0.08 M ascorbic acid did reduce the formation of the by-product acrylamide, a harmful substance in food. When the concentration of ascorbic acid added reached 0.04 M, the content of acrylamide in the ammonia caramel was 20.53 μg/L, which was approximately 44% lower than that without ascorbic acid. As a result, ascorbic acid can be considered to improve the quality and safety of ammonia caramels.

Purification, characterization and kinetic properties of extracellular l-asparaginase produced by Cladosporium sp.

L-asparaginase from Cladosporium sp. grown on wheat bran by SSF was purified. Enzyme appeared to be a trimer with homodimer of 37 kDa and another 47 kDa amounting to total mass of 121 kDa as estimated by SDS-PAGE and 120 kDa on gel filtration column. The optimum temperature and pH of the enzyme were 30 °C and 6.3, respectively with Vmax of 4.44 μmol/mL/min and Km of 0.1 M. Substrate specificity studies indicated that, L-asparaginase has greater affinity towards L-asparagine with substrate hydrolysis efficiency (Vmax/Km ratio) eightfold higher than that of L-glutamine. L-asparaginase activity in presence of thiols studied showed decrease in Vmax and increase in Km, indicating nonessential mode of inactivation. Among the thiols tested, β-mercaptomethanol, exerted inhibitory effect, suggesting a critical role of disulphide linkages in maintaining a suitable conformation of the enzyme. Metal ions such as Ca(2+), Co(2+), Cu(2+), Mg(2+), Na(+), K(+) and Zn(2+) significantly affected enzyme activity whereas presence of Fe(3+), Pb(2+) and KI stimulated the activity. Detergents studied also enhanced L-asparaginase activity. In-vitro half-life of purified L-asparaginase in mammalian blood serum was 93.69 h. The enzyme inhibited acrylamide formation in potato chips by 96 % making it a potential candidate for food industry to reduce acrylamide content in starchy fried food commodities.