Lipid concomitant γ-oryzanol decreased oil absorbency of French fries by changing the microstructure of French fries and physical properties of frying oil.

BACKGROUND: The aim of this research was to evaluate the possibility of lipid concomitant γ-oryzanol reducing oil absorbency of fried foods and the underlying mechanism. Therefore, the influence of γ-oryzanol on moisture and oil content, and distribution and micromorphology of French fries and the viscosity, fatty acid composition and total polar compounds content of rice bran oil (RBO) after frying were studied. RESULTS: Our results showed that the incorporation of low concentration of γ-oryzanol [low addition group (LAG)] (5.754 g/kg) decreased the oil absorbency and porous structure of French fries during frying. Additionally, LAG incorporation inhibited the degradation of linoleic acid, decreased the growth rate of saturated fatty acids, total polar compounds and viscosity of frying oil. CONCLUSIONS: Consequently, it was recommended to incorporate a small amount of γ-oryzanol in frying oil because it could inhibit oil absorption behavior of French fries. © 2023 Society of Chemical Industry.

Evaluation of the efficiency of thermostable L-asparaginase from B. licheniformis UDS-5 for acrylamide mitigation during preparation of French fries.

A thermostable L-asparaginase was produced from Bacillus licheniformis UDS-5 (GenBank accession number, OP117154). The production conditions were optimized by the Plackett Burman method, followed by the Box Behnken method, where the enzyme production was enhanced up to fourfold. It secreted L-asparaginase optimally in the medium, pH 7, containing 0.5% (w/v) peptone, 1% (w/v) sodium chloride, 0.15% (w/v) beef extract, 0.15% (w/v) yeast extract, 3% (w/v) L-asparagine at 50 °C for 96 h. The enzyme, with a molecular weight of 85 kDa, was purified by ion exchange chromatography and size exclusion chromatography with better purification fold and percent yield. It displayed optimal catalysis at 70 °C in 20 mM Tris-Cl buffer, pH 8. The purified enzyme also exhibited significant salt tolerance too, making it a suitable candidate for the food application. The L-asparaginase was employed at different doses to evaluate its ability to mitigate acrylamide, while preparing French fries without any prior treatment. The salient attributes of B. licheniformis UDS-5 L-asparaginase, such as greater thermal stability, salt stability and acrylamide reduction in starchy foods, highlights its possible application in the food industry.

In vitro genotoxicity assessment of French fries from mass catering companies: a preliminary study.

It is generally assumed that French fries are likely to have weak in vitro mutagenic activity, but most studies thereof have only assessed gene mutations. In this article, the genotoxicity of 10 extracts of French fries was assessed using the in vitro micronucleus test (following the principles of the OECD 487 guidelines). Each sample was obtained from a different mass catering company in Navarra (Spain). This assay, together with the Ames test, is recommended in the basic in vitro phase included in the European Food Safety Authority Opinion on Genotoxicity Testing Strategies Applicable to Food and Feed Safety Assessment. Eight of 10 samples from mass catering companies induced chromosomal aberrations in the in vitro micronucleus test. Moreover, French fries deep-fried in the laboratory for different periods of time (0, 3, 5, 10, 20, 30 min) were assessed using the in vitro micronucleus test. Genotoxicity was observed in all time periods from 3 min on. The biological relevance of these results must be further explored.

Study of the behavior and properties of frying oil on repetitive deep frying.

The current work focused on the effect of repetitive frying on the physicochemical characteristics of palm oil (PO)and sesame oil (SO) during the preparation of french fries by deep fat frying. A total of 16 frying cycles were carried out and the effect on various parameters was evaluated. The repetitive frying caused higher damage to sesame oil as compared with PO as observed from changes in FFA and PV which increased to 0.63 ± 0.12, 1.31 ± 0.16%, and 2.71 ± 0.02, 7.21 ± 0.01 meq/kg from an initial value of 0.28 ± 0.00, 0.93 ± 0.16% and 0.19 ± 0.00, 0.71 ± 0.00 meq/kg for PO, SO respectively. The fatty acid composition of SO showed significant change with a decrease in linoleic acid and oleic acid content from 42.7 ± 0.01 to 28.1 ± 0.03 and 36.2 ± 0.01 to 25.1 ± 0.01 after 16 frying cycles respectively. The oleic acid content of PO was less affected it decreased from an initial value of 42.4 ± 0.01 to 38.9 ± 0.01 after 16 cycles. The fatty acid composition of PO made it more stable to the repetitive frying process. The physical properties like density refractive index and viscosity of SO were badly affected by repetitive frying. The french fries fried in PO score higher overall acceptability in the sensory examination. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05774-4.

Processed potatoes intake and risk of type 2 diabetes: a systematic review and meta-analysis of nine prospective cohort studies.

The current cohort study shows the inconsistent association between potato consumption and the risk of type 2 diabetes mellitus (T2DM). Therefore, we conducted a systematic review and dose-response meta-analysis of published prospective cohort studies to quantitatively estimate this association. We searched PubMed, Embase, MEDLINE, Web of Knowledge, and the Cochrane Library up to September 2019 for all published articles. Seven of the articles reported nine cohort studies with 383,211 participants, with 23,189 T2DM cases that met the inclusion criteria and were included for our analysis. The results of random effects model pooled relative risk (RR) showed an association between potato intake and the risk of T2DM (pooled RR = 1.13, 95% CI: 1.02-1.26, p > 0.01). In the subgroup analysis, French fries, long-term follow-up, large sample size, and high-quality studies were associated with an increased T2DM risk. Further, a linear dose-response analysis indicated that 100 g/day increment of total potato (RR = 1.05, 95% CI: 1.02-1.08) and French fries (RR = 1.10, 95% CI: 1.07-1.14) consumption may increase the risk of T2DM by 5% and 10%, respectively. Our meta-analysis showed that potato consumption, especially French fries consumption, was associated with increased T2DM risk.

Screening of Acrylamide of Par-Fried Frozen French Fries Using Portable FT-IR Spectroscopy.

Current assays for acrylamide screening rely heavily on LC-MS/MS or GC-MS, techniques that are not suitable to support point of manufacturing verification because it can take several weeks to receive results from a laboratory. A portable sensor that can detect acrylamide levels in real-time would enable in-house testing to safeguard both the safety of the consumer and the economic security of the agricultural supplier. Our objective was to develop a rapid, accurate, and real-time screening technique to detect the acrylamide content in par-fried frozen French fries based on a portable infrared device. Par-fried French fries (n = 70) were manufactured at times ranging from 1 to 5.5 min at 180 °C to yield a wide range of acrylamide levels. Spectra of samples were collected using a portable FT-IR device operating from 4000 to 700 cm-1. Acrylamide was extracted using QuEChERS and quantified using uHPLC-MS/MS. Predictive algorithms were generated using partial least squares regression (PLSR). Acrylamide levels in French fries ranged from 52.0 to 812.8 µg/kg. The best performance of the prediction algorithms required transformation of the acrylamide levels using a logarithm function with models giving a coefficient of correlation (Rcv) of 0.93 and RPD as 3.8, which means the mid-IR model can be used for process control applications. Our data corroborate the potential of portable infrared devices for acrylamide screening of high-risk foods.

Comparative analysis of aroma compounds in French fries and palm oil at three crucial stages by GC/MS-olfactometry, odor activity values, and aroma recombination.

BACKGROUND: Flavor is a key element affecting the popularity of French fries (FFs). When oil is heated, the changes in oil quality can affect the flavor of the food directly. RESULTS: The flavor of FFs showed three crucial stages: the break-in (3.0% to 6.8% of total polar compounds (TPC)), optimum (7.0% to 19% of TPC), and degrading (above 19.5% of TPC) stages. To distinguish the key aroma compounds in the three stages, the FFs, prepared in palm oil (PO) at TPC of 3.0% (FF3), 7.5% (FF8), 19.5% (FF20), and their relevant oils (PO3, PO8, PO20), were selected for molecular sensory science analysis. The results indicated that the concentration of (E, E)-2,4-decadienal linked with the deep-fried odor was low in FF3, which led to a lower sensory score in the FF3 sample. The FF8 sample had a high (E, E)-2,4-decadienal content and received a high sensory score. The FF20 sample possessed high hexanoic acid, heptanoic acid (sweaty odor), benzaldehyde (stale odor), octanoic acid (sweaty odor), (E)-2-undecenal (fatty odor), and trans-4,5-epoxy-(E)-2-decenal (metallic odor) content, thus leading to FFs having an undesirable flavor and PO20 showed high hexanoic acid and heptanoic acid content, contributing to a lower sensory score in PO20. CONCLUSION: The FFs' flavor became undesirable when TPC was above 19.5% due to significant influences of some off-flavor compounds. It is therefore essential to prevent the generation of rancid substances to prolong the optimum stage during frying. © 2021 Society of Chemical Industry.

Radio frequency as an innovative method to produce low-fat French fries.

BACKGROUND: A large amount of evidence shows that excessive fat intake can increase the risk of obesity, type 2 diabetes, non-alcoholic fatty liver disease, and cardiovascular disease. The main purpose of this study was to use radio frequency (RF) technology to prepare low-fat French fries. RESULTS: RF treatment for 10 min significantly decreased the force required to cut potatoes and inhibited the enzymatic browning of fresh-cut potatoes. Moreover, RF treatment increased the hardness, gumminess, and chewiness of French fries from 388.55 g, 85.67, and 33.27 to 776.93 g, 159.36, and 70.11, respectively. Furthermore, RF treatment for 10 min reduced the oil content of French fries by 28.0% compared to that of the control group. This result was related to the pre-gelatinized potato starch content after RF treatment. Pre-gelatinized starch forms a 'protective film', that prevents oil from entering the fries during frying. CONCLUSION: Moderate RF treatment (10 min) reduced the oil content of French fries without making their texture significantly different from that of commercial French fries. These findings may provide a new perspective for the application of RF technology in the development of low-fat fried foods. © 2022 Society of Chemical Industry.

Insight into the effect of fatty acid composition on the texture of French fries.

BACKGROUND: Several researchers have reported that the texture of fries is affected by the fatty acid composition of oil, although the mechanism of this effect is not clear. In this regard, fries were fried in refined rapeseed oil and fully hydrogenated rapeseed oil with diverse proportions (0%, 20%, 40%, 60%, 80% and 100%) and were analyzed based on the content of moisture and oil, texture, thermal properties, crystalline properties and microstructure. RESULTS: The outcomes presented that fries fried in fully hydrogenated oil had less oil absorption and moisture loss than those fried in refined oil. The results from the texture analyzer, differential scanning calorimetry and X-ray diffraction showed that hardness, enthalpy and relative crystallinity increased with an increase in the proportion of fully hydrogenated oil. However, the peaks of starch-lipid complexes were hardly observed during frying. Furthermore, scanning electron microscopy results displayed that some physically trapped fat was observed in fries fried in mixed hydrogenated oil. Stereomicroscope images showed that the crust thickness of the fries increased slightly with an increase in the proportion of fully hydrogenated oil. CONCLUSION: Overall, the upsurge in crust thickness and oil crystals was responsible for an increase in the hardness of the fries. This indicated that the texture of fries can be manipulated by altering the fatty acid composition of the oil. © 2021 Society of Chemical Industry.

Effect of new antioxidants: phenolipids on quality of fried French fries and rapeseed oil.

The purpose of this work was to evaluate the effect of five novel synthetic antioxidants: octyl sinapate (OSA), octyl ferulate (OFA), octyl caffeate (OCA), cetyl sinapate (CSA) and cetyl ferulate (CFA) added to refined rapeseed oil for the first time on antioxidant activity (AA) and total phenolic content (TPC) in French fries. French fries after frying in enriched oils had higher the AA determined by three assays: 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS = 2907-20,029 µmol TE/100 g), 2,2-diphenyl-1-picrylhydrazyl (DPPH = 657-6886 µmol TE/100 g), ferric reducing antioxidant power (FRAP = 332-2659 µmol TE/100 g) and total phenolic content (TPC = 44-378 mg SA/100 g) than those prepared in refined rapeseed oil (ABTS = 2146 µmol TE/100 g, DPPH = 403 µmol TE/100 g, FRAP = 218 µmol TE/100 g, TPC = 14 mg SA/100 g). Moreover, the presence of phenolipids in rapeseed oil decreased the oil content in fried French fries by 22-45%. However, the AA and TPC in the fortified oils significantly increased, whereas slower changes in oxidation parameters of supplemented oils after frying were observed. A new lipophilic antioxidants can be useful for the development of management system for the preparation of French fries and the prolongation of frying oil shelf life.

Addition of lipophilic grape seed proanthocyanidin effectively reduces acrylamide formation.

BACKGROUND: In this article the relationship between lipophilic grape seed proanthocyanidin (LGSP) and acrylamide formation in potato-based products was investigated. The acrylamide, reducing sugar, asparagine, and 3-aminopropionamide contents were determined by high-performance liquid chromatography mass spectrometry (HPLC-MS). Sensory evaluation was used to evaluate the quality of the products. RESULTS: The results showed that LGSP presented greater inhibition effect on the acrylamide formation than the commonly used commercial antioxidants. Furthermore, 81.5% and 84.7% of acrylamide was reduced in potato crisps and French fries after adding 0.1% and 0.05% LGSP (w/w) in palm oil, respectively. When the concentrations of LGSP were less than 0.1%, there was no significant difference between LGSP-treated samples and control sample for sensory evaluation. CONCLUSION: Thus, LGSP is effective in reducing the level of acrylamide and maintaining the reasonable sensory attributes of potato fried foods. The results indicate that LGSP may be used as a potential additive for reducing acrylamide formation in fried foods. © 2019 Society of Chemical Industry.

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

BACKGROUND: This study attempted to evaluate the effect of fat-soluble anti-oxidants in vegetable oils on acrylamide during the deep-fat frying of French fries. METHODS: Three 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. RESULTS: The 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 ß-carotene content after the 10th frying session was the highest in red palm oil. CONCLUSION: The 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.

Reduction in Dietary Acrylamide Exposure-Impact of Potatoes with Low Acrylamide Potential.

Acrylamide forms primarily from a reaction between reducing sugars (e.g., glucose and fructose) and an amino acid (asparagine, Asn) formed naturally in foods, including potatoes. This reaction occurs when carbohydrate-rich foods are heated at temperatures above 120 °C. Multiple potato varieties were transformed with potato genomic DNA that results in down-regulation of the expression of the asparagine synthetase-1 gene (Asn1), significantly reducing synthesis of free Asn, and consequently lowering the potential to form acrylamide during cooking. These potatoes with low acrylamide potential (LAP) were tested in agronomic trials, and processed into French fries and potato chips. Decreased levels of acrylamide were measured in these cooked food products when derived from LAP potatoes compared with those derived from conventional potatoes. These reductions can be directly attributed to reduction in Asn levels in the LAP potatoes. The corresponding average reduction in exposure to acrylamide from French fry and potato chip consumption is estimated to be 65%, which would amount to approximately a 25% reduction in overall dietary exposure. Considering that children consume nearly three times more acrylamide than adults on a per kg body weight basis, they would experience the most impact from the reduced acrylamide associated with LAP potatoes. The potential public health impacts, in context of dietary acrylamide exposure reduction, are discussed in this study.

Effect of Guar Gum with Sorbitol Coating on the Properties and Oil Absorption of French Fries.

This paper investigated the effects of guar gum with sorbitol coating on the oil absorption of French fries by combined dye oil methods, confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The results showed that pretreatment of blanching with calcium ions and coating with guar gum and sorbitol could significantly reduce the structural oil (STO) and penetrated surface oil (PSO) of French fries and have no negative effects on its texture and also effectively control the final moisture content (p < 0.05). Compared with control or samples coated with guar gum (blanching with or without calcium ions), the total oil (TO) of French fries with guar gum and sorbitol reduced by 50.8%, 33.1% and 30.6%, respectively. CLSM photographs confirmed that STO significantly reduced after coating with guar gum and sorbitol, followed by PSO. In the process of frying, the coatings of guar gum or guar gum with sorbitol could effectively prevent oil from infiltrating the potato tissue, which can be seen in the SEM photographs. The barrier properties of French fries were enhanced by coating guar gum, and sorbitol was added to avoid pores and cracks. Blanching with calcium ion can significantly reduce the final moisture content of coating French fries.

Effect of low-temperature long-time and high-temperature short-time blanching and frying treatments on the French fry quality of six Irish potato cultivars.

Processing conditions are an important determinant of French fry quality. However, the effect of low-temperature long-time (LTLT) and high-temperature short-time (HTST) blanching and frying treatments has not been investigated in many cultivars. The current study investigates the effect of the sequential application of these treatments on French fries processed from six Irish potato cultivars (Fianna, Innovator, Mondial, Navigator, Panamera and Savanna). Blanching was effected at 75 °C for 10 min or 85 °C for 5 min and frying was effected at 160 °C for 2 min or 180 °C for 1 min. These treatments resulted in significant differences in the quality of the fries across the cultivars. The blanching treatments had a greater impact on the French fry quality than the frying treatments. LTLT blanching resulted in lower oil (12-13% fresh mass basis [fmb]), and higher protein (3.5-4.3% fmb) and mineral content in the French fries processed from Innovator, compared to HTST blanching. This was accompanied by a crispier crust, which required a greater puncture force (1.2-2.1 N) for penetration. Blanching with the LTLT treatment before HTST frying resulted in French fries that were the most acceptable to consumers and these were from Fianna, Innovator and Mondial. The current study demonstrates that the effect of French fry processing conditions is cultivar-dependent.

Cross-flow deep fat frying and its effect on fry quality distribution and mobility.

Conventional industrial frying systems are not optimised towards homogeneous product quality, which is partly related to poor oil distribution across the packed bed of fries. In this study we investigate an alternative frying system with an oil cross-flow from bottom to top through a packed bed of fries. Fluidization of rectangular fries during frying was characterised with a modified Ergun equation. Mixing was visualized by using two coloured layers of fries and quantified in terms of mixing entropy. Smaller fries mixed quickly during frying, while longer fries exhibited much less mixing, which was attributed to the higher minimum fluidization velocity and slower dehydration for longer fries. The cross-flow velocity was found an important parameter for the homogeneity of the moisture content of fries. Increased oil velocities positively affected moisture distribution due to a higher oil refresh rate. However, inducing fluidization caused the moisture distribution to become unpredictable due to bed instabilities.

Production of low fat french-fries with single and multi-layer hydrocolloid coatings.

In this study the influence of coating with different hydrocolloids on the oil absorption and quality attributes of French fries was investigated. Our results revealed that hydrocolloid coatings reduced the moisture loss during frying, and hence, reduced the oil uptake of French fries. Among the studied gums as a single layer coating, combination of carboxy methyl cellulose and pectin (0.5 and 1% w/w) lead to the lowest oil uptake of French fries. In samples coated with two and three-layer hydrocolloids, the oil absorption reduced further and the moisture content of final products was higher than the blank samples.

Dietary acrylamide exposure and health risk assessment of pregnant women: A case study from Türkiye.

This study aimed to determine the acrylamide exposure of pregnant women resulting from the consumption of bread, coffee, and French fries and to evaluate it in terms of carcinogenic and non-carcinogenic health risks. Retrospective 24-h food consumption data of pregnant women (n = 487) was obtained using the Food Frequency Questionnaire (FFQ). Dietary acrylamide exposure was calculated according to a deterministic model, and the data were assessed by hazard index (HI) and carcinogenic risk (CR). The mean daily acrylamide exposure of pregnant women aged 18-30 and ≥31 years and in the 1st, 2nd, and 3rd trimesters was 31.4, 35.4, 38.7, 31.3, and 32.4 µg/day, respectively. The acrylamide exposure data were not significantly different among different age groups and pregnancy periods (p > .05). Dietary acrylamide exposure in pregnant women of different age groups and trimesters may cause significant and serious health problems in terms of carcinogenic risk. According to their level of contribution to average acrylamide exposure, the foods were ranked as follows: French fries> bread> coffee. There is a significant risk of cancer due to exposure to acrylamide from French fries and bread other than coffee. The findings suggest that pregnant women should avoid consuming French fries, bread, and coffee with high acrylamide levels for both their own health and their newborns' health.

Analysis of oxidation products and toxic compounds in edible and blended oil during the deep-frying of french fries.

This study sought to analyze the oxidative products [acid value (AV), free fatty acids (FFA), conjugated dienoic acid (CDA), p-anisidine value (p-AV), antioxidant-prooxidant balance (APB) value] and toxic compounds [3-monochloropropane diol (3-MCPD), glycidyl ester (GE)] in edible oils after deep-frying. The deep-frying edible oils evaluated herein included soybean oil (S), palm oil (P), canola oil (C), grape seed oil (G), and a 1:1 blend (SC, SG, PC, PG, and CG). As frying time increased, the level of AV in PC, total FFA contents in CG, and p-AV in CG significantly increased up to 200%, 45.5%, and 410.5%, respectively (p < 0.05). The levels of 3-MCPD, and GE were 0.81-6.28 µg/mL and 0.14-2.84 µg/mL, respectively. The levels of 3-MCPD, GE, CDA, and APB changed significantly as frying time increased. Analysis of the correlation between oxidation products and toxic compounds indicated that the contents of 3-MCPD and palmitic acid were positively correlated. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01494-9.

Garlic Extract Increased Acrylamide Formation in French Fries Obtained by Different Cooking Methods.

Fried potato products are the largest dietary source of acrylamide, a potential carcinogen formed at high temperatures. Previous studies suggested that garlic powder could decrease the development of acrylamide; however, there has not been much focus on the effect of garlic extract. The aim of this study was to investigate the effect of garlic extract exposure on the development of acrylamide in French fries in popular home cooking techniques such as pan-frying, air-frying, and oven-frying. Initially, the antioxidative profile, total phenolic content, and chlorogenic acid content of garlic were analyzed. Subsequently, potatoes were treated with garlic extract and fried using pan-frying, air-frying, and oven-frying techniques. Acrylamide levels were then quantified through HPLC and compared to control groups. The findings showed that garlic exposure increased the acrylamide formation in French fries obtained with air-frying (311.95 ± 0.5 µg/kg) and with oven-frying (270.32 ± 23.4 µg/kg) (p < 0.005 *). This study offers new insights into varying acrylamide formation levels in domestic practices. Unlike previous studies, this study is the first to question the effect of aqueous garlic extract exposure. Further research is required to comprehend the interaction between garlic exposure and acrylamide formation in household settings.