Vitamin C or ascorbic acid is a basic nutrient, a highly effective antioxidant, widely used as food additive. Therefore, quality control in food industry demands ascorbic acid determination methods. The purpose of this study was to determine vitamin C in natural orange juices by spectrometric and voltammetric methods. Another goal was to determine the kinetic and thermodynamics activation parameters for ascorbic acid degradation in orange juices over time and at different temperatures. It was observed that during storage, ascorbic acid concentrations in orange juices were gradually decreased with time at a rate depending on storage temperature and type of orange juice. The reaction order was determined through integrated graphical analysis where the dependences of ln c_t/c₀ as a function of time reveals the high values for R², indicating that the kinetics of the degradation of AA follows first order reaction at both studied temperatures. For studied samples the loss of ascorbic acid was varied between 4.33% and 9.13%. Enthalpy variation (ΔH) and entropy variation (ΔS) of activation process were obtained from the Eyring–Polany model based on transition state theory. The values of activation energy ranged between 7289.24 kJmol^-1 and 15689.54 kJmol^-1.

Recently, consumers’ awareness is becoming a crucial aspect driving the food industry to develop new products with high nutritional value. Oil industry explores the use of less known plant materials such as avocado fruit which is a rich source of bioactive compounds. The objective of this study was to assess quality and oxidative stability of avocado pulp oils during a 2-month storage period. Two avocado varieties, Hass and Reed were selected and oil extraction was performed with the use of hexane. The extent of oxidative deterioration and oils stability were tested by measuring the acid value and peroxide value. The PDSC method was applied to evaluate the oxidative induction time. The composition of fatty acids and their distribution in internal (sn-2) and external (sn-1 and sn-3) positions in triacylglycerols were also analysed. The acid value and the peroxide value of fresh extracted avocado oils reached approximately 0,6 mg KOH g^-1 fat and 5 meq O₂ kg^-1 fat, respectively. Generally, during avocado oils storage both the acid values and the peroxide values were in accordance with Codex Alimentarius requirements (the limit of acid value is 4 mg KOH g^-1 fat, while for the peroxide value is 15 meq O₂ kg^-1 fat). The Hass avocado pulp oil was characterized by higher value of the oxidative induction time, about 111 min, compared to the oil extracted from Reed avocado pulp (61 min). The GC analysis revealed that avocado pulp oil could be considered as a source of monounsaturated fatty acids. The dominant fatty acid found in this group was oleic acid with percentage share of above 60%. In accordance with the results of fatty acids distribution in triacylglycerols molecules, the main fatty acids in the sn-2 position were linoleic acid and oleic acid and their percentage share in this item was up to 59% and 34%, respectively. It was also noticed that after a 2-month storage period, the acid value and the peroxide value increased about 7-fold and 2-fold, the oxidative induction time decreased about 2-fold and the percentage shares of fatty acids groups changed. In conclusion, the results obtained in this research indicate that storage period has significant impact on avocado pulp oils quality.

Global food systems are no longer sustainable for health, the environment, animal biodiversity and wellbeing, culinary traditions, socioeconomics, or small farmers. The increasing massive consumption of animal foods has been identified as a major determinant of unsustainability. However, today, the increasing consumption of ultra-processed foods (UPFs) worldwide is also questioned. Up today, more than 40 epidemiological studies have shown that excess UPF consumption signficantly increase the risks of several chronic diseases and all-cause mortality. Concerning the other dimensions of sustainability, we attempted, based on the collection of scattered data from scientific literature, to build the interrelations between massive UPF consumption and impacts on food systems. For this, we first identified the main ingredients/additives present in UPFs and the agricultural practices involved in their provision to agro-industrials. Overall, UPF production is analysed regarding its impacts on the environment, biodiversity, animal wellbeing, and cultural and socio-economic dimensions. Our main conclusion is that UPFs are associated with intensive agriculture/livestock and threaten all dimensions of food system sustainability due to the combination of low-cost ingredients at purchase and increased consumption worldwide. However, plant-based UPFs do not produce the highest greenhouse gas emissions (GHGEs) compared to conventional meat and dairy products. In addition, only reducing energy-dense UPF consumption (associated with excess calorie intakes), without substitution, might substantially reduce GHGEs. Therefore, significant improvement in food system sustainability requires urgently encouraging limiting UPF consumption to the benefit of mildly processed foods, preferably seasonal, organic and local products, a recommendation that we formalized in the concept of the 3V-based diet for Végétal (Plant), Vrai (Real foods), Varié (Varied, preferably organic, local and seasonal - when possible).

Listeria monocytogenes – a Gram-positive intracellular bacteria is one of the most virulent foodborne pathogens. A common strategy used to control the growth of bacteria in food is using food additives. However, many bacterial species are resistant to food preservatives, and bacterial resistance can be natural or acquired. Therefore, there is a constant need for searching for new compounds with antimicrobial properties. The purpose of the present study was to evaluate the efficiency of five (ethyl, butyl, hexyl, octyl, and decyl) esters of 4-hydroxyphenylpropanoic acid against L. monocytogenes PCM 2191. Esters were obtained in reactions catalyzed by Candida antarctica lipase B. Purified esters with structures confirmed by ¹H NMR were applied to determine minimal inhibitory concentrations (MIC) using microdilution broth method. MIC values ranged 0.0625 – 16 mM. The results of this study have demonstrated the potential application of 4-hydroxyphenylpropanoic acid alkyl esters in inhibiting the growth of Listeria monocytogenes. Octyl 4-hydroxyphenylpropanoate proved to be the best antimicrobial agent and was used in time-kill assay with different concentrations of 1 x MIC, 4 x MIC, and 16 x MIC. Three to nine log reduction of cell number were observed compared to control medium without any antimicrobial compound after 24 hours, and the possibility of using octyl 4-hydroxyphenylpropanoate in food applications is worth further investigation.

Chia oleogel as a potential fat substitute in cooked meat sausages.

Meat products reformulation is very complicated since the “charcuterie” is more than a technology. The addition of new ingredients is not an easy task; therefore, preliminary assays are carried out to determine their feasibility. Oleogels are "new ingredients" used as saturated fat substitutes in meat products. Chia oil was used as a fatty ingredient to produce an oleogel (COG), which was used as pork backfat substitute (substitution level 0, 25, 50, and 75%) in a Frankfurter-type sausage. To evaluate the feasibility of this substitution, several physicochemical parameters were determined: 2-Thiobarbiturc acid test (TBA), moisture, fat, pH, water activity (Aw), and residual nitrite level (RNL). The last 3 parameters were evaluated during storage time (21 days). RNL was not detected in samples with COG. Samples with 75% COG showed higher moisture than the others. All samples with COG showed higher pH (without changes during storage time) and lower Aw values than the control. Samples with 50 and 75% COG substitution showed higher TBA values than the others. All samples showed similar fat content (22.35-23.85 g fat/100 g). Thus, this chia oleogel was successfully applied (at 50%) in Frankfurter-type sausages, highlighting its effect on the RNL.

FEDER/MCI-Spain, AEI. AGL2016-75687-C2-2-R (MCI/AEI/FEDER/UE). HealthyMeat network, CYTED-119RT0568.

Lentinus edodes (Shiitake) is an edible mushroom cultivated and marketed due to its nutritional and medicinal values (1). L. edodes is appreciated for its unique fragrant taste, its high dietetic potential is valuable for health and its bioactive molecules explain its interest as medicinal mushroom (1). This mushroom can be grown using various substrates and culture conditions (2). Our work focused on the comparison of nutraceutical compounds (i. e., amino acids and ergosterol) of L. edodes fruit bodies cultivated in organic or non-organic growing conditions in the French Occitanie region (2). Sequential extraction was performed on freeze dried fungal materials. Quantitative evaluation of amino acids was done using HP-TLC, dosage of ergosterol was carried out using HPLC. For both nutraceutics, differences were highlighted between extracts (depending on the nature of the solvents) and between growing conditions (organic versus non-organic). For example, extracts from non-organic producers have the highest levels of alanine and the lowest contents of isoleucine. Extracts from organic producer contain a significantly higher content of ergosterol. This work demonstrated that culture conditions influence the chemical profile of mushrooms (in our case, Lentinus edodes), particularly nutraceutics compounds which could improve nutrition and human health.

1) Rathore H, Prasad S, Sharma S. Mushroom nutraceuticals for improved nutrition and better human health: A review. Pharma Nutrition. 2017; 5:35-46.

2) Diallo I, Boudard F, Morel S, Vitou M, Guzman C, Saint N, Michel A, Rapior S, Traoré L, Poucheret P, Fons F. Antioxidant and anti-inflammatory potential of Shiitake culinary-medicinal mushroom, Lentinus edodes (Agaricomycetes) sporophores from various culture conditions. Int J Med Mushrooms. 2020; 22:535-546.

Consumers are being encouraged to increase the protein and fibre consumption through convenient and healthy food products. In this study, six samples of extruded rice snacks were developed by substituting rice flour with cowpea flour and whey protein concentrate. The instrumental texture, colour and sensory analysis were performed by seventy untrained individuals who answered an overall liking question using the 9-point hedonic scale and a CATA (Check-All-That-Apply) question with 37 attributes and emotions. Hedonic scores were significantly different with texture, taste and overall liking (p<0.05). The crispy and crunchy CATA attributes were associated with 15-20% cowpea and 5-10% WPC incorporations. Results of the instrumental and sensory analysis were compared, and a correlation between mechanical and sensory texture and the colour was observed. A principal component analysis (PCA) revealed that significant positive correlation between the groups, crispiness and L* value, and hardness b* and a* values, respectively. The results of the present study will help guide for innovative high protein and fibre plant food design and formulation.

Oat products are often chosen by people leading a healthy lifestyle for their health-promoting properties. Oats and oats based products are characterized by a higher fat content with a favorable fatty acid composition compared to other cereals. It is of great importance to control the quality of fat fraction as an important indicator of food products safety. In this study fat isolated from oats products such as: whole grain oatmeal, mountain oatmeal, instant oatmeal was analyzed. In the fat tested, the composition of fatty acids by gas chromatography; distribution of fatty acids in the internal and external positions of triacylglycerols by the method based on the ability of the pancreatic lipase to selectively hydrolyze ester bonds in the sn-1,3 positions were determined. The oxidative stability of the tested fat was evaluated using pressure differential scanning calorimetry. The induction time as a primary parameter of the resistance of fats to their oxidative decomposition was defined. Melting profiles of the analyzed fat were determined by differential scanning calorimetry.

Based on the conducted research, it was found that fat isolated from the examined oat products is a rich source of unsaturated fatty acids. In sn-2 position of triacylglycerols, the highest share of oleic acid was found. The fat isolated from the tested products was characterized by the highest proportion of linoleic acid in the sn-1,3 positions of the triacylglycerols. It was also observed that the induction time of oxidation of fat isolated from oats products, reached the values of 28.79 min - 39.07 min in the test conducted at 120°C and 5.84 min – 7.37 min. - at 140°C. In the course of the melting curves of fat, two distinct endothermic peaks were found. The analyzed melting profiles showed the presence of peaks indicating the presence of low-melting fat fractions in the isolated fat, rich in polyunsaturated and monounsaturated fatty acids.

Lettuce (Lactuca sativa L.) is one of the most important leafy greens worldwide. Nutritional value of its edible leaf depends on different factors including lettuce’s type and growing conditions. The aim of this study was to investigate bioactive compounds accumulation, antioxidant activity and growth behavior of twenty-two lettuce genotypes, cultivated under field and greenhouse conditions. Total phenolic compound, chlorophylls, carotenoids, anthocyanin contents, and antioxidant activities were analyzed by spectrophotometric methods. The data were examined with ANOVA and further explored by principal component analysis. Significant differences between bioactive compounds, antioxidant activity and growth behavior were found among cultivars and morphological types, for both growth conditions. Carotenoid and chlorophylls content was higher in greenhouse conditions for all genotypes. In field production, butterhead and iceberg lettuces showed lowers content of these bioactive compounds. The red-pigmented Falbala cultivar from field production showed the highest level of polyphenols and anthocyanin. Meanwhile, in greenhouse condition, the oak leaf cultivar Grenadine displayed the highest concentration of these phenolic compounds. The iceberg type lettuces showed the lowers percentages of antioxidant activity in both environments. The results point out the impact of growth conditions and the high variability in lettuce bioactive compounds accumulation and antioxidant activity.

The process of making chocolate, like many other technological processes, is highly temperature-dependent. One of the unfavorable changes that may take place during the process of making dark chocolate is the oxidation of cocoa butter, which may prevent the process of appropriate crystallization leading to the most desirable polymorphic form V. The parameter that allows predicting the sensitivity of the sample to oxidation is the activation energy of the oxidation process. The study aimed to compare three dark chocolates and preceding cocoa masses at different stages of production, produced by three different manufacturers using different production methods, based on thermal analysis of fats extracted from mentioned cocoa masses and statistical analysis of the results to assess the impact of production conditions on the oxidative stability of the fat phase. The Ozawa-Flynn-Wall method based on the Arrhenius equation was used to estimate the activation energy (E_a) and the pre-exponential factor (Z). A DSC apparatus (Q20, TA Instruments), calibrated with pure indium, was used for the tests. The measurements were carried out using non-isothermal mode with the following sample heating rates: 2.5 K/min, 4 K/min, 6 K/min, 7.5 K/min, 10 K/min, 12.5 K/min, 15 K/min. The mass of the samples used for the test was about 3 - 4 mg. An increase in the activation energy corresponding to the increase in fat oxidative stability was observed in the case of raw dark chocolate from a small company and classic dark chocolate from a large company. Moreover, in the case of classic dark chocolate produced by a small manufacturer, the stability of fat in the final product was much lower (65.36 kJ/mol) than that of the starting material such as cocoa butter (123.89 kJ/mol) or cocoa liquor (104.68 kJ/mol). In most of cases, the activation energy values calculated from the maximum oxidation temperature/peak maximum (T_max) were significantly lower than the values calculated from the extrapolated oxidation onset temperature (T_on) with just two exceptions: cocoa butter used by a large manufacturer (Ea_(Ton) = 82.43 kJ/mol, Ea_(Tmax) = 105.10 kJ/mol) and the final product (chocolate bar) of a small manufacturer of classic dark chocolate (Ea_(Ton) = 65.36 kJ/mol, Ea_(Tmax) = 94.05 kJ/mol), both showed the opposite trend.