Acrylamide Formation In Model Systems Research Articles

Acrylamide formation in apple juice concentrates during storage

This study investigated the acrylamide formation in model systems, laboratory-scale produced apple juice concentrates obtained from different stages of process, and commercial apple juice concentrates at different Brix levels during the storage. Changes in the concentrations of reducing sugars, asparagine, 5-hydroxymethylfurfural, 3-deoxyglucosone, and acrylamide were monitored. In addition, Schiff bases of 3-deoxyglucosone and 5-hydroxymethylfurfural with asparagine were confirmed using high-resolution mass spectrometry in order to understand the contribution of intermediates to acrylamide formation. The results revealed that acrylamide formed in both acidic-aqueous model systems and laboratory-scale apple juice concentrates during production. The concentrations of 3-deoxyglucosone, 5-hydroxymethylfurfural, and acrylamide increased significantly (p<0.05) with the increase in Brix levels whereas asparagine levels decreased in commercial apple juice concentrates during storage. The concentration of acrylamide reached at the maximum level of 0.30 ± 0.02 µmol/kg dry matter in 70 °Bx of the concentrates. The findings showed that long-term storage of apple juice concentrates at high Brix levels contributes the acrylamide formation even in unsuitable systems such as acidic and high moisture medium. The confirmation of Schiff base of 3-deoxyglucosone and 5-hydroxymethylfurfural with asparagine demonstrated that the acrylamide formation was attributed to the accumulation of intermediates leading to the conversion of asparagine to acrylamide.

Influence of citral on acrylamide formation in model systems

This work aimed to evaluate the role of citral (Cit) in the formation of acrylamide (AA) in model systems. The asparagine (Asn)/glucose (Glc), Asn/Glc/ginger essential oil (GEO), and Asn/Glc/Cit model systems were prepared and analysed by UPLC-MS/MS. Cit was implicated to be a major product that contributed to the enhancement of AA formation by GEO. The addition of Cit significantly enhanced the formation of AA in the Asn/Glc model system in a dose-dependent manner. Further analysis showed Cit rather than its oxidation product played a major role in AA formation. Cit not only directly reacted with Asn via the Maillard reaction producing AA but also promoted the formation of AA between Asn and Glc.

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.

Activities of hydrocolloids as inhibitors of acrylamide formation in model systems and fried potato strips

Effects of eight hydrocolloids on acrylamide (AA) formation were compared. At 2% (w/w), pectin, alginic acid (>50% reduction) and xanthan gum (∼20%) significantly ( P < 0.05) reduced acrylamide formation in chemical models. In the fried snack model, effective inhibition of acrylamide formation (∼30%) by most of the hydrocolloids was observed only when the concentration was increased to 5%. Immersing potato strips for 1 h in a 1% alginic acid solution before frying produced inhibition of acrylamide formation similar to that in a 5% solution, and immersing for 5 h led to a significantly lower AA content (∼60% versus ∼30% reduction) compared with immersing for 1 h in a 1% or 5% immersion solution. Similar phenomena were also observed for pectin. The findings suggest alginic acid and pectin are promising inhibitors of acrylamide formation, and immersion time is an important determinant for their effects against acrylamide formation in fried potato products.

Influence of sodium chloride on colour, residual volatiles and acrylamide formation in model systems and breakfast cereals

SummaryTo elucidate the salt action in breakfast cereals to decrease its amount without a quality loss, a model system was developed. This model, composed of native maize starch, glucose and a mixture of five amino acids (glucose/amino acids molar ratio = 1/1) generated similar colour and volatiles (m/z = 45, 59, 69, 73, 87 and 103 g mol−1) after heating compared to commercial breakfast cereals. A designed experiment used this model to study the influence of salt concentration (0–5.44%), heating time (0–25 min) and temperature (180–230 °C) on colour, residual volatiles and acrylamide formation. The higher the salt concentration, heating time and temperature, the darker were the products (P &lt; 0.05). The L* values of the model systems containing 5 % salt and heated for 25 min at 230 °C were twelve points lower than the same systems without salt heated in the same conditions. Presence of salt significantly decreased acrylamide formation in the model systems (up to 50 % decrease when 2.5 % salt is added). However, salt did not have a significant impact on volatile levels. These findings were confirmed by observations made on four types of commercial breakfast cereals.

Contribution of Lipid Oxidation Products to Acrylamide Formation in Model Systems

The reactions of asparagine with methyl linoleate ( 1), methyl 13-hydroperoxyoctadeca-9,11-dienoate ( 2), methyl 13-hydroxyoctadeca-9,11-dienoate ( 3), methyl 13-oxooctadeca-9,11-dienoate ( 4), methyl 9,10-epoxy-13-hydroxy-11-octadecenoate ( 5), methyl 9,10-epoxy-13-oxo-11-octadecenoate ( 6), 2,4-decadienal ( 7), 2-octenal ( 8), 4,5-epoxy-2-decenal ( 9), and benzaldehyde ( 10) were studied to determine the potential contribution of lipid derivatives to acrylamide formation in heated foodstuffs. Reaction mixtures were heated in sealed tubes for 10 min at 180 degrees C under nitrogen. The reactivity of the assayed compounds was 7 >> 9 > 4 > 2 >> 8 approximately 6 >> 10 approximately 5. The presence of compounds 1 and 3 did not result in the formation of acrylamide. These results suggested that alpha,beta,gamma,delta-diunsaturated carbonyl compounds were the most reactive compounds for this reaction followed by lipid hydroperoxides, more likely as a consequence of the thermal decomposition of these last compounds to produce alpha,beta,gamma,delta-diunsaturated carbonyl compounds. However, in the presence of glucose this reactivity changed, and compound 1/glucose mixtures showed a positive synergism (synergism factor = 1.6), which was observed neither in methyl stearate/glucose mixtures nor in the presence of antioxidants. This synergism is proposed to be a consequence of the formation of free radicals during the asparagine/glucose Maillard reaction, which oxidized the lipid and facilitated its reaction with the amino acid. These results suggest that both unoxidized and oxidized lipids are able to contribute to the conversion of asparagine into acrylamide, but unoxidized lipids need to be oxidized as a preliminary step.

Study of factors affecting acrylamide levels in model systems

The factors important for the acrylamide formation in model systems were studied. The effects of two starch matrices (potato, wheat), the share of two monosaccharides (glucose and fructose) on the formation of acrylamide, and the impact of water addition were compared in model systems under isothermal conditions. Acrylamide was determined by GC/MS-NCI technique. The results showed that the water content is one of the most important factors in the formation of acrylamide, besides the reaction temperature and time. The minimum of acrylamide formation was observed at the water content between 25 and 40%; outside of this range, the acrylamide concentration was higher. The presence of starch reduced the amount of acrylamide formed from asparagine and saccharide, moreover, the effects of potato and wheat starches were similar. Fructose was more effective for the acrylamide formation in comparison with glucose. The combined contribution of glucose and fructose in the mixture with asparagine and starch to the acrylamide level corresponded to the sum of separate contributions of saccharides only at the middle content of added water. &amp;nbsp; &amp;nbsp;

Acrylamide in heated potato products – analytics and formation routes

AbstractAcrylamide is a highly polar, water‐soluble molecule with low, but significant volatility. Most common methods for determination of acrylamide are high performance liquid chromatography‐tandem mass spectrometry (LC‐MS‐MS), gas chromatography‐mass spectrometry (GC‐MS) after bromination, GC‐MS without and LC‐MS after derivatisation with mercaptobenzoic acid. The different clean‐up procedures used are presented and the advantages and disadvantages of the individual methods are discussed. Acrylamide is formed during food preparation if free asparagine and reducing sugars are present, water activity is low and the product temperature exceeds 100 °C. The influence of different parameters on acrylamide formation in model systems is discussed. In fried potatoes the greatest amount of acrylamide is formed from asparagine and reducing sugars. Alternative routes of formation, as for example via acrolein and acrylic acid are much less important.

The role of creatine in the generation of N-methylacrylamide: a new toxicant in cooked meat.

Investigations of different sources of acrylamide formation in model systems consisting of amino acids and sugars have indicated the presence of two pathways of acrylamide generation; the main pathway specifically involves asparagine to directly produce acrylamide after a sugar-assisted decarboxylation step, and the second, nonspecific pathway involves the initial formation of acrylic acid from different sources and its subsequent interaction with ammonia and/or amines to produce acrylamide or its N-alkylated derivatives. Aspartic acid, beta-alanine, and carnosine were found to follow the acrylic acid pathway. Labeling studies using [(13)C-4]aspartic acid have confirmed the occurrence in this amino acid of a previously proposed sugar-assisted decarboxylation mechanism identified in the asparagine/glucose model system. In addition, creatine was found to be a good source of methylamine in model systems and was responsible for the formation of N-methylacrylamide through the acrylic acid pathway. Labeling studies using creatine (methyl-d(3)) and (15)NH(4)Cl have indicated that both the nitrogen and the methyl groups of methylamine had originated from creatine. Furthermore, analysis of cooked meat samples has also confirmed the formation of N-methylacrylamide during cooking.