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This study aimed to investigate the ability of lactic acid bacteria to remove cholesterol in simulated gastric and intestinal fluids. The findings showed that the amount of cholesterol removed was dependent on the biomass, viability, and bacterial strain. Some cholesterol binding was stable and not released during gastrointestinal transit. The presence of cholesterol affected the fatty acid profile of bacterial cells, potentially influencing their metabolism and functioning. However, adding cholesterol did not significantly impact the survival of lactic acid bacteria during gastrointestinal transit. Storage time, passage, and bacterial culture type did not show significant effects on cholesterol content in fermented dairy products. Variations in cell survival were observed among lactic acid bacteria strains in simulated gastric and intestinal fluids, depending on the environment. Higher milk protein content was found to be more protective for bacterial cells during gastrointestinal transit than fat content. Future research should aim to better understand the impact of cholesterol on lactic acid bacteria metabolism and identify potential health benefits.

Total phenolic content (TPC) and phenolic profiles of extracts of the aerial parts of coriander ( Coriandrum sativum L.), lovage ( Levisticum officinale Koch.), and tarragon ( Artemisia dracunculus L.), and leaves of Indian borage ( Plectranthus amboinicus ) have been investigated. The extracts were prepared using 70% ( v/v ) ethanol and fresh or air-dried herbal material. Besides phenolic composition, DPPH • and ABTS •+ scavenging activity, and ferric-reducing antioxidant power (FRAP) were determined. The extracts from dried herbal materials exhibited higher TPC and more potent antioxidant activity than those from fresh counterparts. The highest TPC (146.77 g GAE/kg extract) and antioxidant activity (0.491, 0.643, and 0.396 mol TE/kg extract in DPPH, ABTS, and FRAP assays, respectively) were detected for the extract from dried leaves of Indian borage, while the lowest values were determined for the extract from fresh aerial parts of coriander. Five phenolic acids (rosmarinic, chlorogenic, caffeic, ferulic, and neochlorogenic acids) and four flavonoids ((+)-catechin, rutin, hyperoside, and astragalin) were identified in the samples. Only caffeic acid was present in all extracts. Its content in the extracts of dried tarragon and Indian borage was lower than in those of the fresh material. A significant correlation was found between antioxidant activity and the content of phenolic acids. Rutin was found to be the major flavonoid in most extracts. Based on the present study results, the possibility of using the extracts obtained from both fresh and air-dried herbs as potential components for functional food formulation can be considered in the future.

This article describes the evaluation of the anthocyanins stability in yogurts with strawberry, sour cherry, and blueberry fruit preparation during 8-week storage period under refrigerated condition. The differences in anthocyanin degradation rate and color changes between stirred yogurts and fruit-on-the-bottom yogurts (fruit preparation was on-the-bottom of package) were compared. Anthocyanin content in fruit yogurts showed a significant decreased during the storage, especially for the first 2 weeks. There were differences in the rate of pigment degradation between yogurt obtained from a different species of fruit. The half-life of the pigments in stirred yogurt with the preparation of strawberry, sour cherry, and blueberry was found to be 5.5, 6.7, and 19.0 weeks, respectively. The addition of fruit preparation on the bottom of yogurt could be used to reduce the pigment degradation during storage. The half-life of anthocyanin in fruit-on-the-bottom yogurts was 39-63% higher than in the blending samples. A significant alteration in the pigment profile during storage of blueberry yoghurt was observed. The proportion of malvidin-glucosides and acylated anthocyanins increased with time of storage, with a concomitant decrease in proportion of petunidin, delphinidin and peonidin derivatives.

For the production of fermented milk drinks, cultures of microorganisms other than traditionally applied can be used. Such possibilities are created by the symbiotic culture of bacteria and yeast (SCOBY), which is used to produce kombucha. The aim of the study was to evaluate the possibility of using kombucha and the SCOBY for fermented milk drink products. The drinks were developed with a lactose-free variant and traditional milk. For the analysis of the obtained beverages, microbiological methods (CFU method), chemical methods (pH method and HPLC method) and the quantitative descriptive analysis (QDA) sensory method were used. As a result of the research, a recipe and the fermentation parameters for fermented milk drinks were developed. In the developed lactose milk drinks, the average lactose content was 4.25 g/100 g. In lactose-free milk drinks, the average glucose content was 2.26 g/100 g. Lactic acid in both types of products was at the highest average level of 0.68 g/100 g. The products had a characteristic pH value for fermented milk drinks and a very good microbiological quality, which followed the FAO/WHO guidelines. Drinks also had a typical sensory profile for this products group. However, slight sensory defects were detected. The developed fermented milk drinks have a potential health-promoting value, thanks to the content of active microflora and organic acids, which have a confirmed positive effect on the human body. The drinks produced require further testing to optimize their cost of production, possible health benefits and sensory quality.

Bacteria from the Propionibacterium genus consists of two principal groups: cutaneous and classical. Cutaneous Propionibacterium are considered primary pathogens to humans, whereas classical Propionibacterium are widely used in the food and pharmaceutical industries. Bacteria from the Propionibacterium genus are capable of synthesizing numerous valuable compounds with a wide industrial usage. Biomass of the bacteria from the Propionibacterium genus constitutes sources of vitamins from the B group, including B12, trehalose, and numerous bacteriocins. These bacteria are also capable of synthesizing organic acids such as propionic acid and acetic acid. Because of GRAS status and their health-promoting characteristics, bacteria from the Propionibacterium genus and their metabolites (propionic acid, vitamin B12, and trehalose) are commonly used in the cosmetic, pharmaceutical, food, and other industries. They are also used as additives in fodders for livestock. In this review, we present the major species of Propionibacterium and their properties and provide an overview of their functions and applications. This review also presents current literature concerned with the possibilities of using Propionibacterium spp. to obtain valuable metabolites. It also presents the biosynthetic pathways as well as the impact of the genetic and environmental factors on the efficiency of their production.

The effect of microwave heating (800 W) of whole and dehulled rapeseeds for 2 to 8 min was investigated in order to evaluate the impact of dehulling in conjunction with microwaving on the nutritional value, antioxidant activity and physicochemical properties of virgin rapeseed oil. Control oil produced from dehulled seeds (DRO) had higher amounts of bioactive compounds, such as tocochromanols and phytosterols, lower content of pigments, and higher content of primary and secondary oxidation products compared to oil pressed from whole seeds (WRO). Oils pressed from seeds that had previously undergone thermal treatment demonstrated gradual increase of oxidative stability, radical scavenging activity, moreover microwave treatment to caused darkening of oil, assessed in terms of changes in L*a*b* coordinates as well as browning index. Thermally-induced compositional changes were seen mainly in canolol, phytosterols, and carotenoids content, while only slight increase of tocopherols and phenolics was observed. The most pronounced effect of microwave pretreatment was noted for canolol formation—for 8-min MV exposure canolol quantity was approximately 7- and 23-fold higher, in comparison with control WRO and DRO samples, respectively (increase from 61.39 to 456.04 µg/g, and from 13.39 to 320.44 µg/g).

In this study, the effect of rapeseed mechanical hulling and thermal pre-treatment by microwaves (from 2 to 10 min with 2-min intervals, 800 W) and roasting (from 20 to 100 min with 20-min intervals, 165 °C) on the content of phytochemicals in the oil was investigated. Results showed that both pre-treatments applied differentiated the oils in terms of the content of bioactive compounds. In general, oils pressed from hulled and thermally pre-treated seeds contained higher content of tocopherols, PC-8 and phytosterols, while oils pressed from non-hulled and pre-processed seeds had significantly higher concentration of polyphenols. Both microwaving and roasting contributed to an increase of antioxidant capacity of studied oils. The increase of radical scavenging activity of oils was seen mainly in hydrophilic fraction of oil, which was highly positively correlated with the amount of canolol formed during seeds heating.

This study determined and compared the contents of bioactive components in plant seed oils extracted with n-hexane (Soxhlet method) and chloroform/methanol (Folch method) from coriander, caraway, anise, nutmeg and white mustard seeds. Oleic acid dominated among unsaturated fatty acids in nutmeg and anise seed oils while petroselinic acid was present in coriander and caraway oils. Concerning sterols, β-sitosterol was the main component in seed oils extracted with both methods. The content of total phenolics in nutmeg, white mustard and coriander seed oils extracted with chloroform/methanol was higher than in their counterparts prepared with n-hexane. The seed oil samples extracted according to the Folch method exhibited a higher ability to scavenge DPPH radicals compared to the oil samples prepared with the Soxhlet method. DPPH values of the methanolic extracts derived from oils produced with the Folch method were also higher than in the oils extracted with n-hexane.

Six extra virgin olive oils (EVOOs) available on Croatian market and twelve home-made Croatian extra virgin olive oils were characterized in this paper. Eleven home-made extra virgin olive oils were obtained from the cultivar Oblica and only one was from the domestic cultivar Buharica. All home-made samples were produced on the island Brac in Dalmatia and were collected directly from the producers. The main goal of the study was to recognize the aroma markers of bioactive food components present in Croatian extra virgin olive oils. After statistical analysis, which was performed with the Kendall test of independence, only eighteen volatile compounds were chosen to describe the statistical relationship of selected components and their volatile markers. For instance, 3-hexenyl acetate, 2,4-hexadienal, trans-2-hexenal, α-copaene were identified as volatile markers of fatty acids. Nonanol, 1-octanol, 2-octenal, heptanoic acid, and hexanoic acid were identified as volatile markers of some phenolic acids. (E)-β-ocimene, nonanal, and 6-methyl-5-hepten-2-one were recognized as phytosterol volatile markers.

The total phenolic content (TPC) and antioxidant capacity as determined by 2,2-diphenyl-1-picrylhydrazyl, 2,2ʹ-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid and ferric reducing antioxidant power assays of spice extracts such as rosemary, lemon balm, hyssop, nettle and cumin seeds were investigated. The effect of spice extracts on the growth of selected lactic acid bacteria (LAB) was also analysed. Lemon balm extract exhibited the highest TPC and antioxidant capacity while the nettle and cumin seeds extracts were characterized by the lowest values. Spice extracts had no impact on the growth of the most tested LAB except for rosemary extract, which showed an inhibitory effect towards all strains of Lactobacillus acidophilus and L. delbrueckii. These results suggest that spice extracts may be considered as additives in dairy and meat products in which LAB are present.

Rosa rugosapetals are a rich source of phenolic compounds, which determined their antioxidant properties. The aim of this study was to determine the polyphenolic composition of not processed petals ofRosa rugosacollected from the commodity crops and to determine the variability of the contained therein polyphenols between harvesting seasons. Twenty polyphenols were identified by UPLC-ESI-MS. The main fraction of polyphenols was ellagitannins, which are 69 to 74% of the total polyphenols of the petals. In the petals ofRosa rugosa, four anthocyanins have been identified: cyanidin 3,5-di-O-glucoside, peonidin 3-O-sophoroside, peonidin 3,5-di-O-glucoside, and peonidin 3-O-glucoside, of which the predominant peonidin 3,5-di-O-glucoside represented approx. 85% of all the determined anthocyanin compounds. It was found that the petals ofRosa rugosaare a valuable source of bioactive compounds and can be considered as a healthy valuable resource.

Kombucha is a healthy beverage which is a final result of tea fermentation by adding a starter culture of the acetic acid bacteria and yeasts. The effect of fermentation conditions on physicochemical, microbiological and sensory properties of Kombucha tea beverages was evaluated with emphasis placed on determining sugars and organic acids content, including pro-health glucuronic acid. Fermentation process was conducted for 10 days at 20°C, 25°C and 30°C. The optimal conditions for the fermentation of Kombucha tea beverages were a temperature of 25°C and a period of 10 days which allowed to retrieve a product with good physicochemical, microbiological and sensory quality. The content of glucuronic acid increased during fermentation at all temperatures reaching the highest, on the 10th day of fermentation at 25°C. It was observed that all beverages were a good overall quality, whereas Kombucha fermented at 25°C was assessed as the highest. La fermentación de té, mediante la incorporación de cultivo iniciador de bacterias acidoacéticas y levaduras, produce la saludable bebida llamada Kombucha. Para efectos de este estudio, la valoración del efecto que las condiciones de fermentación tienen en las propiedades fisicoquímicas, microbiológicas y sensoriales de bebidas de té de Kombucha se centró en la determinación de azúcares y de la concentración de ácidos orgánicos, incluyendo el beneficioso ácido glucurónico. El proceso de fermentación se extendió 10 días a temperaturas de 20°C, 25°C y 30°C, constatándose que una temperatura de 25°C y un tiempo de 10 días constituyen condiciones óptimas para fermentar bebidas de té de Kombucha, ya que el producto resultante presentó buena calidad fisicoquímica, microbiológica y sensorial. A todas las temperaturas probadas, se comprobó que durante el proceso de fermentación aumentó la concentración de ácido glucurónico, alcanzando el contenido más elevado en el décimo día de fermentación a una temperatura de 25°C. Aunque se verificó que todas las bebidas presentaban buena calidad general, el té de Kombucha fermentado a 25°C mostró la valoración más alta.

Composición química y resistencia a la oxidación de aceite de colza alto oleico prensado de semillas intactas y descascarilladas pre-tratadas con microondas. En este estudio se investigó la influencia del pretratamiento con microondas (MV) en las propiedades fisicoquímicas del aceite de colza alto oleico preparado a partir de semillas húmedas (HORO) y descascarilladas (DHORO) (3, 6, 9 min, 800W). El control DHORO contenía un nivel más alto de tocoferoles totales y carotenoides, mientras que se detectó una mayor concentración de compuestos fenólicos totales y clorofilas en el HORO. El pretratamiento de MV provocó una disminución en el contenido de ácidos grasos insaturados que fue más evidente para los DHOROs. El tiempo de microondas afectó significativamente al contenido fitoquímico y al color de ambos tipos de aceites. Se observó un gran aumento de la concentración de canolol después de 9 min de microondas, que aumentó 506 y 155 veces en el HORO y DHORO, respectivamente. Al mismo tiempo, la capacidad antioxidante del aceite producido a partir de semillas pretratadas de MV durante 9 min fue casi 4 veces mayor que la del aceite de control para ambos tipos de aceites. The influence of a microwave (MV) pre-treatment (3, 6, 9 min, 800W) on the physicochemical properties of high-oleic rapeseed oil prepared from intact (HORO) and de-hulled seeds (DHORO) was investigated in this study. A control DHORO contained higher levels of total tocopherols and carotenoids, while higher concentrations of total phenolic compounds and chlorophylls were detected in the HORO. The MV pre-treatment caused a decrease in the unsaturated fatty acids content that was more evident for the DHOROs. The microwaving time significantly affected phytochemical contents and the color of both types of oils. A vast increase in canolol concentration was noticeable following 9 min of microwaving, which increased 506- and 155-fold in the HORO and DHORO, respectively. At the same time, the antioxidant capacity of oil produced from MV pre-treated seeds for 9 min was nearly 4 times higher than that of the control oil for both types of oils.

The focus of this study was to compare the volatile compounds of unfermented and fermented milk samples containing Lactobacillus casei DN-114 001. Samples were analysed by headspace solid phase micro extraction-gas chromatography-mass spectrometry and pH changes were monitored on day zero and at weeks 2 and 4 of storage at 6 °C. Acetic acid was present as the dominant compound in all fermented samples and non-fermented samples from the 2nd week of storage. Other identified compounds were: 2-butanone, ethanol, 2-pentanone, 2-heptanone, amylol, acetoin, 2-nonanone, propionic acid, butyric acid, isovaleric acid, caproic acid, dodecanol, and caprylic acid. Comparison of the volatile compound profiles using cluster analysis revealed a similarity of volatile compounds of fermented and unfermented milk samples stored for 4 weeks. Cluster-analysis comparison and an artificial neural network model enabled demonstration of the close relationship between model non-fermented milk and a commercially-available milk product.

Dependent on anthocyanin pigments, colour is one of the main quality factors of berry products. In this paper we assess the influence of probiotic bacteria on the degradation rate of anthocyanins in yoghurts with a highbush blueberry preparation during storage. Four types of yoghurts were prepared: first with the yoghurt starter culture YC-X16 only (Steptococcus thermophilus and Lactobacilllus delbrueckii subsp. bulgaricus) and three more, each with the starter culture YC-X16 and one of the three probiotic cultures: Bb-12, La-5 and LCP, respectively (Bif. animalis subsp. lactis – Bb-12; Lactobacillus. acidophilus – La-5 and Lactobacillus. paracasei subsp. paracasei – LCP). Derivatives of malvidin were the predominant anthocyanins in the tested yoghurts. Degradation of pigments occurred in accordance with the first-order reaction and its half-life time depended on the bacterial cultures. Anthocyanins in the probiotic yoghurt made with LCP culture were characterized by lower stability than those made with the other bacterial cultures. The impact of lactic bacteria or their metabolic products on the stability of anthocyanins in berry yoghurts shows that an appropriate selection of culture for production of yoghurt is recommended.

Storage stability and degradation kinetics of phenolic compounds in rapeseed oil pressed from microwave treated seeds (0, 2, 4, 6, 8, 10 min, 800 W) during long-term storage (12 months) at a temperature of 20 °C was discussed in the current study. The dominant phenolic compound detected in rapeseed oil was canolol, followed by minor amounts of free phenolic acids and sinapine. The most pronounced effect of seeds microwaving was noted for canolol formation – after 10-min exposure the quantity of this compound was approximately 63-fold higher than in control oil. The degradation of phenolics during storage displayed pseudo first-order kinetics. Differences in the initial degradation rate (r0) demonstrated significant impact of the period of seeds microwave exposure on the degradation rates of phenolic compounds. Results of the half-life calculation (t1/2) showed that the storage stability of phenolic compounds was higher in oils produced from microwave treated rapeseeds than in control oil.

International audience; The objectives of this study were (i) to test different conditions of freezing, thawing, and grinding during sample preparation and (ii) to evaluate the possibility of using mid-infrared spectroscopy for analyzing the composition of sugars, organic acids, and polyphenols in apples. Seven commercial apple cultivars were chosen for their large variability in composition (total polyphenols from 406 to 1033 mg kg −1 fresh weight). The different conditions of sample preparation affected only the phenolic compounds and not sugars or organic acids. The regression models of the mid-infrared spectra showed a good ability to estimate sugar and organic acid contents (R 2 ≥ 0.96), except for citric acid. Good predictions were obtained for total phenolic, flavan-3-ols, and procyanidins (R 2 ≥ 0.94) provided oxidation was avoided during sample preparation. A rapid and simple procedure was then proposed for phenolic compounds using sodium fluoride during sample homogenization at ambient temperature and freeze-drying before spectra acquisition. Mid-infrared (MIR) has been shown to be a suitable technique for high-throughput analysis of the major constituents in fruit juices, homogenates, and extracts. 1−7 These studies have been aimed to assay soluble solids content, titratable acidity, and the concentrations of individual sugars, organic acids, and total phenolic compounds. It would be highly beneficial if it could also be applied to the analysis of specific metabolites such as individual polyphenols. Indeed, the quantification of these compounds requires chemicals and solvents, equipment such as high-performance liquid chromatography coupled to a diode array detector, good technical skill, and time. However, the development of high-throughput analyses has been hindered by the high reactivity of some molecules such as polyphenols. Hence, this study aimed at identifying the simplest and cheapest sample preparation for MIR application for poly-phenol quantification. The fruit chosen for this methodological optimization was apple, as it is among the most consumed fruits worldwide and indeed a good source of polyphenols in the French diet. 8 A regular consumption of apples provides a large amount of polyphenolic compounds such as flavan-3-ols (procyanidins and catechins), dihydrochalcones (phloridzin), hydroxycinnamic acids (chlorogenic acid and p-coumaroyl-quinic acid), flavonols (quercetin), and anthocyanins. A large variability exists according to the studied cultivars with, for example, a variation of total phenolic content between 523 and 2724 mg kg −1 dry weight (DW) among 67 new and old apple varieties. 9

Celem pracy bylo porownanie wplywu dodatku mrozonych śliwek (5 lub 10%) oraz kwasu askorbinowego (0,05%) na wybrane wlaściwości burgerow wieprzowych (wydajnośc, pH, zawartośc wody i tluszczu, wskaźnik TBARS oznaczany po 1 dniu i po 13 dniach przechowywania w opakowaniu prozniowym w temp. 3-7oC). Dodawane śliwki zostaly scharakteryzowane pod wzgledem zawartości wybranych skladnikow chemicznych (m.in. cukrow, kwasow ogolem, antocyjanow i polifenoli ogolem). Stwierdzono obecnośc w owocach substancji znanych ze swojej aktywności przeciwutleniającej. Wlaściwości przeciwutleniające śliwek zostaly potwierdzone po ich wprowadzeniu do burgerow. Śliwki zmniejszaly wskaźnik TBARS w burgerach o 69% lub 82% w porownaniu z probą kontrolną, odpowiednio przy 5- i 10-procentowym dodatku, natomiast kwas askorbinowy obnizal ten wskaźnik o 90%. Pakowanie prozniowe produktow wyeliminowalo w nich zmiany wskaźnika TBARS miedzy 1 a 13 dniem przechowywania. Negatywnym skutkiem wprowadzenia śliwek do receptury burgerow wieprzowych bylo zmniejszenie ich wydajności po obrobce cieplnej.

The present study focuses on the kinetics of degradation of phytochemicals and antioxidant capacity during long-term storage of rapeseed oils prepared from microwave (MV) pre-treated seeds (2–10 min, 800 W). A maximum tocochromanols (90.48 mg/100 g) and phenolic compounds (mainly canolol, 1692.15 μg g−1) concentration is achieved after 10 min of seeds MV pre-treatment, while the highest content of carotenoids (1017.51 μg/100 g) is found in the oils pressed from seeds exposed to microwaves for 6 min. During storage, the tocochromanols and carotenoids decrease following zero-order kinetic, the reduction of phenolic compounds display pseudo first-order kinetic. Storage stability of tocochromanols in the oils obtained from MV pre-treated seeds is comparable to that of the control oil. Oils produced from 8 min MV pre-treated seeds show the slowest progress of carotenoids reduction, as the values of degradation rate constant (k) are lower (14.678 μg/100 g/month) than that of the control oil (18.168 μg/100 g/month). The half-life (t1/2) of oils phenolic compounds increases with longer seeds exposition to MV. Practical Applications: Numerous studies have shown favorable effect of oilseeds thermal pre-processing on the concentration of phytochemicals in the resulting oil. However, there is lack of information regarding storage stability of oils prepared from microwave pre-treated seeds. As the prediction of shelf-life is a desirable goal in the food industry, evaluation of phytochemicals degradation based on the kinetic models will provide information on cost-effectiveness of the seeds thermal pre-treatment prior to oil cold-pressing. The present study focuses on the kinetics of degradation of phytochemicals during long-term storage of rapeseed oils prepared from microwave pre-treated seeds. The study includes a comparative study of kinetics of tocochromanols, carotenoids, and phenolic compounds in correlation with changes in the antioxidant capacity. It is shown that the content of phytochemicals in the oil and their storage stability is significantly affected by the time of seeds microwave pre-treatment prior to pressing.

Fruits form an important part of a healthy human diet as they contain many ingredients with proven pro-health effects such as vitamins, phenolic compounds, organic acids, fiber, and minerals. The purpose of this work was to evaluate the effect of pullulan coating on the quality and shelf life of highbush blueberry during storage. General appearance, weight loss, dry matter, soluble solid content, reducing sugars, content of L-ascorbic acid, phenolic compounds (total phenolics, phenolics acids and anthocyanins) were determined in uncoated and coated blueberries fruits. The microbiological efficiency of pullulan coating was also evaluated. All parameters were monitored during storage at 4 °C and 16 °C by 28 and 14 days, respectively. The study showed that pullulan coating protects perishable food products especially susceptible to mechanical injury including fruits such as blueberries. Pullulan acts as a barrier that minimizes respiration rate, delaying deterioration and controlling microbial growth.

The purpose of the present study was to extend knowledge concerning the effect of rapeseeds pre-processing methods on the changes in oxidative state, alterations within fatty acids contents and colour of oil. Thermal pre-treatment of non-hulled and hulled rapeseeds by microwave radiation (2-10 min, 800 W, 2450 MHz) was studied in comparison with conventional roasting (20-100 min, 165°C). As rapeseeds were thermally pre-treated, with longer time a significant increase (p < 0.05) in the amounts of total carotenoids, chlorophylls and phenolics in the oils pressed from microwaved and roasted seeds was found. Oils pressed from hulled seeds (HRO) were characterised by significantly lighter yellow hue than non-hulled (NHRO) ones; however, the microwaving and roasting time significantly affected colour change of both types of oils. Although induction period increased with longer seeds microwaving and roasting, oils pressed from thermally pre-treated seeds exhibited higher level of primary and secondary oxidation. Additionally, prolonged seeds heating resulted in unsaturated fatty acids degradation as detected by GC-FID. Based on the results obtained by applying principal component analysis (PCA) it can be concluded that within much shorter rapeseed exposition to microwaves similar compositional changes and degree of oxidation of oils was achieved as during conventional roasting. Practical applications: Colour of edible oil is an important commercial parameter, whereas oxidative stability need to be monitored to ensure high quality of the finished product. Thermal pre-treatment is currently being used in oilseeds pre-processing, but very little researches studied its effect on colour change and oxidative state of oil. Although rapeseed thermal pre-treatment can cause a number of positive quality changes, such as an increase of bioactive compounds, the results should be interpreted with caution since application of too harsh heating conditions may result in unsaturated fatty acids degradation, lipid oxidation or undesirable colour change.

International audience; The objective of this study was to investigate the possibility of predicting the quality parameters of tomato by mid-infrared spectroscopy. For 2 years, tomato samples, representing a large variability in the chemical composition, were scanned using the attenuated total reflectance accessory of a Fourier transform spectrometer in the wavenumber region between 4000 and 400 cm−1. Calibration models were developed using partial least squares (PLS) regression method and were tested with internal validation sample set in the first year. Different spectral preprocessing techniques were investigated and different spectral regions were selected to optimise the calibration models. In addition, the models obtained in 2007 were used to predict the soluble solids, dry matter and total acidity in tomato harvested in 2008. The regression models of the spectra showed reasonable ability to estimate the dry matter, soluble solids, total acidity, citric acid and individual sugars contents in tomatoes grown in 2007, with high coefficients of determination (from 0.98 for soluble solids to 0.92 for fructose) and low percentage errors of prediction (from 3% to 7% for soluble solids and citric acid, respectively). By contrast, the predictive capability of model for malic acid was unsatisfactory with error of prediction of 26%. When the best calibration models from 2007 were used to predict the selected parameters in tomato picked in 2008, very high correlations were obtained, confirmed by low errors of prediction, from 4% to 7% for dry matter and total acidity, respectively. Mid-infrared spectroscopy is an attractive alternative for standard methods for determination of internal quality parameters in tomato