Performance of Olive-Pomace Oils in Discontinuous and Continuous Frying. Comparative Behavior with Sunflower Oils and High-Oleic Sunflower Oils

Frying performance of olive-pomace oils (OPOs) as compared to sunflower oils (SOs) and high-oleic sunflower oils (HOSOs) was studied in discontinuous frying (DF) and continuous frying (CF) for the first time. DF is used in household, restaurants and frying outlets, while CF is used in the food industry. Oil alteration during frying was determined by measurements of polar compounds (PC) and polymers. Fried potatoes were analyzed for oil absorption and alteration, color, and evaluated in an acceptability test. Results for DF showed that all SOs reached 25% PC at the 9th frying operation (FO), whereas HOSOs did between the 17–18th FO and variable results were found for OPOs since initial levels of diacylglycerols were different. Rates of formation of PC or polymers were the lowest for OPOs, thus showing the best performance in DF. Specifically for PC, relative rates of formation were 1.00–1.11, 2.46–2.71 and 1.37–1.41 for OPOs, SOs and HOSOs respectively. In CF, OPOs and HOSOs behaved similarly and better than SOs, although none reached 25% PC after 40 FO. The good performance of OPOs can be attributed to the high monounsaturated-to-polyunsaturated ratio, in common with HOSOs, and the additional positive effect of minor compounds, especially β-sitosterol and squalene.

Stability of Bioactive Compounds in Olive-Pomace Oil at Frying Temperature and Incorporation into Fried Foods

The stability of minor bioactive compounds in olive-pomace oils (OPOs) was evaluated at frying temperature under the conditions of a thermoxidation test. Bioactive compounds analyzed included squalene, tocopherols, sterols, triterpenic acids and alcohols, and aliphatic alcohols. In order to determine the amount of OPO bioactive compounds incorporated into foods after frying, three different kinds of frozen products were selected, i.e., pre-fried potatoes (French fries), pre-fried battered chicken nuggets, and chicken croquettes (breaded patties), and were used in discontinuous frying experiments. Results obtained in both the thermoxidation and frying studies showed high stability of triterpenic alcohols (erythrodiol and uvaol), oleanolic acid, and aliphatic alcohols, naturally present in OPOs. In all fried foods, the content of lipids increased after frying, as expected, although the extent of absorption of OPOs into fried foods and the exchange with food lipids depended on the food characteristics. Overall, frying with OPOs improved the nutritional properties of all products tested by increasing the level of oleic acid and by the incorporation of squalene, triterpenic acids and alcohols, and aliphatic alcohols, in significant quantities.

Intake of Potatoes is Associated with Higher Diet Quality, and Improved Nutrient Intake and Adequacy Among US adolescents: NHANES 2001-2018 Analysis.

Background: Potatoes are nutrient rich white vegetables and are most widely consumed staple food. Research on potato consumption and impact on public health is limited and inconclusive. The objective of this study was to provide updated evaluation of the cross-sectional association between potato consumption and diet quality, nutrient intake and adequacy among adolescents. Methods: Two day 24-hour diet recall data from adolescents (n=16,633; age 9-18 years) participating in National Health and Nutrition Examination Survey 2001-2018 were used. Consumers were defined as those consuming any amount of potatoes (baked or boiled potatoes, mashed potatoes and potato mixtures, fried potatoes, and potato chips) on the days of dietary recall. Usual intakes of nutrients were determined using the National Cancer Institute method and diet quality was calculated using the Healthy Eating Index-2015 (HEI-2015) scores after adjusting the data for demographic factors. Results: Intake of potatoes did not change over the last 18 years among US adolescent. Consumers of baked or boiled potatoes, mashed potatoes and potato mixtures had 4.70% higher (P<0.05) HEI-2015 total score and the score gradually increased with increasing intake quartile. HEI-2015 total scores were also higher for consumers of baked or boiled potatoes, mashed potatoes and potato mixtures, and fried potatoes (+2.01%, P<0.05) and for consumers of baked or boiled potatoes, mashed potatoes and potato mixtures, fried potatoes, and potato chips (+1.57%, P<0.05) than non-consumers. Consumers of potatoes had higher (P<0.05) intake of energy and nutrients (dietary fiber, protein, copper, magnesium, phosphorus, potassium, selenium, zinc, niacin, vitamin B6, vitamin C, vitamin K and total choline); and higher (P<0.05) nutrient adequacy for protein, copper, magnesium, phosphorus, potassium, zinc, thiamine, niacin, vitamin B6 and vitamin C, vitamin K than non-consumers. However, potato consumers also had a higher intake of sodium.Conclusion: The results show that potato consumption was associated with better diet quality, higher nutrient intake and improved nutrient adequacy. Potatoes are nutrient rich foods and encouraging their consumption may be an effective strategy for improving intakes and adequacy of key nutrients.Trial Registration: Not applicable, as this was a secondary analysis of publicly available data from the National Health and Nutrition Examination Survey (NHANES).

Formation of ideas about rational nutrition as an element of student’s environmental education

The aim of the work was to form ideas about rational nutrition as an element of ecological education of students by studying and discussing their eating behavior in relation to foods rich in vitamin D using quantitative descriptor-profile analysis. Quantitative descriptor-profile analysis showed that the “poorest” profiles have foods with the highest vitamin D. Thus, foods with a high vitamin D content do not fall into the circle of students’ dietary preferences. The results of the survey showed that the most frequently consumed foods for young people are fried potatoes, pizza, dumplings and cheese. Products such as cheese, butter, artificial red caviar, mushrooms (chanterelles) can be successfully used as a base for fortification with vitamin D, since they are positively perceived by students and affordable. It was shown that cheese is the only product that, when surveyed by 59 young people, was included both in the list of 5 most favorite and frequently consumed foods, and was selected from the list of 22 foods offered to the respondents containing significant amounts of vitamin D. The research carried out is the basis for forming students’ understanding of the importance of a balanced diet in the context of environmental education.

Factors affecting acrylamide mitigation in fried potatoes

Introduction: Recent findings of acrylamide, a carcinogenic agent to humans, in foods have led to great efforts to elucidate the mechanisms of acrylamide formation and its mitigation. The acrylamide was generated during the browning process by the Maillard reaction of amino acid asparagine and reducing sugars at temperatures above 120 °C. Asparagine was determined to be a precursor of acrylamide formation. Therefore, asparagine reduction in raw materials can be taken into account to limit the acrylamide level in prepared foods. L-asparaginase has been used to consume acrylamide precursor by catalyzing the conversion of asparagine into aspartic acid and ammonia. Several factors including enzyme concentration, pH, temperature and frying time can influence the efficiency of acrylamide mitigation by enzyme. In the present work, we selected potatoes as raw materials to investigate the effects of factors on the acrylamide mitigation in fried potatoes. Methods: By pre-treating potato strips in different conditions of enzyme concentrations, pH, temperature and frying time, the effects of these parameters on acrylamide levels in fried products were evaluated by measuring UV-Vis spectra of sample solutions containing acrylamide. The maximum absorbance values at 224 nm were used to determine the acrylamide concentrations by calculation from a calibration curve. Experimental data were statistically analyzed by one-way ANOVA. Colorspace measurements were performed to describe the differences in colors of the fried products after various frying times. Results: A calibration curve was established to determine the acrylamide content of sample solutions via their maximum absorbance values. Pre-treatment of potato strips with a solution of 1.0 IU/mL asparaginase at 37 °C, pH 7.3, for 30 min led to a 45.6% reduction of acrylamide in French fries compared to a solution without enzyme. The optimum pH value for the most efficient enzyme activity was 7.3. Frying time ranging from 1.0 to 6.0 min increased acrylamide content and induced a darker appearance product. Conclusions: By using UV-Vis measurements, we demonstrated the effects of factors on L-asparaginase based acrylamide mitigation in fried potatoes. The conditions which gave the lowest acrylamide concentrations were assessed. The results could be applicable for commercial processes to minimize acrylamide content in prepared potatoes.

Quantifying Oxidized Lipids in Oven Fried and Deep Fried Potatoes: A Three-Way Analysis by LOI, Chemical Assays, and Lipidomics

Objectives Standard chemical methods that determine oxidized lipids in foods are laborious and require toxic chemicals. Our goal was to develop a mathematical lipid oxidation index (LOI) to predict oxidized lipid content of oven fried (OF) and deep fried (DF) potatoes and compare it to standard chemical assays and redox lipidomic analyses. Methods We calculated the LOI value of each recipe using a mathematical formula which consisted of the parameters of 16 nutrients, time and temperature. Next, we OF and DF potatoes in soy, olive, and walnut oils and then extracted oil from the cooked potatoes using the modified Hara and Radin method. We assayed samples of each oil to quantify the conjugated diene (CD), conjugated triene (CT), peroxide (PV), acid (AV), and p-Anisidine (p-Ad) values. In addition, aliquots of each oil sample were sent to collaborators to determine the relative value of oxidized lipids by mass spectrometry and lipidomic informatics. Results Overall, the chemical assays demonstrated that oven frying promoted significantly more oxidation than deep frying. Potatoes OF in walnut oil had greater mean CD (24.1 ± 0.44 vs 19.45 ± 0.06), CT (16.43 ± 0.25 vs 15.67 ± 0.12), AV (0.29 ± 0.01 vs 0.14 ± 0.003), PV (361 ± 7.6 vs 200 ± 6.06), and p-Ad (0.50 ± 0.03 vs 0.14 ± 0.01) when compared to DF potatoes (P ≤ 0.05). This increase in lipid oxidation was not consistent for potatoes prepared with soy and olive oils. LOI predicted a two-fold increase in lipid oxidation in OF potatoes as compared to DF potatoes no matter the type of oil (soy: 308 vs 150; olive: 319 vs; walnut: 330 vs 161). Finally, lipidomic analysis revealed a similar trend in the relative amounts of total oxidized lipids in OF potatoes (soy oil: 24% vs 12%; olive oil: 22% vs 7%; walnut oil 31% vs 17%) and was used to tentatively annotate over 3000 unique oxidized lipids. Conclusions This preliminary study demonstrates that two of the three methods, LOI and lipidomic analysis, are in good agreement in quantifying lipid oxidation in OF and DF potatoes. However, the suboptimal agreement of the chemical assays suggests that the parameters of LOI require further examination. Funding Sources MP is funded by a grant from the Research Dietetic Practice Group (RDPG)/Sugar Association. TW is funded by the Regina Myers McClain Foundation at UCM for his work as a research assistant.