The He-Ne laser (632.8 nm) and photoacoustic spectroscopy (PAS), a variant of the photothermal methods, were combined with the Folin-Ciocalteu colorimetry method to determine total phenolics in wine lees. Utilising this method we found that the total polyphenol content of the nine selected wine lees varied from 1305 to 3907 mg/L. The gallic acid equivalent was determined by means of spectrophotometry using 765 nm as the analytical wavelength. The original Folin-Ciocalteu colorimetry assay was modified for the PAS measurements. Since the PAS does not need dilution, the filtration steps and the Folin-Ciocalteu reagent were used directly on the wine lees samples. Using the original colour reaction process and the modified reaction, the PAS showed linear behaviour between the total polyphenol content and the PA signal; the results of which gave determination coefficients of 0.9946 and 0.9936, while the limit of detection was 232.6 mg/L in both cases.

Rapeseed is a high-quality protein source; however, its quality primarily depends on the variety, origin, and processing method. This study aimed to examine the effectiveness of a mineral supplement (“Peelko”; 27% Ca, 3.5% Mg, 800 mg/kg Fe) in terms of whether it is suitable for reducing the remaining antinutritional substances in cold-pressed rapeseed cake, thereby improving the nutrient content and digestibility of rapeseed. The experiment was carried out with 600 Ross-308 broilers divided into three feeding groups: the control diet contained extracted soybean meal, the R treatment included 10–15% cold-pressed rapeseed cake (in grower and finisher phases), and the R+ treatment consisted of the mineral supplement in addition to the cold-pressed rapeseed cake. R+ had a beneficial effect on the FCR in the grower and finisher feeding phases; moreover, it increased the weight of thyroid glands and the T3 and T4 hormone levels in the blood serum to a lesser extent than R when compared to C (p < 0.05). Diet-specific changes could be observed through the histological examination of thyroid glands, where the acini became larger when the unsupplemented cold-pressed rapeseed cake was fed (R group). Using the mineral supplement (R+ diet) decreased the acinus diameter compared to the R diet, with a similar value to that observed in control birds. The protein content in the breast and fat content in the thigh showed milder changes in R+ than R, compared to C (p < 0.05). The relative ratio of n-6 and n-3 fatty acids narrowed in both R and R+ meat samples compared to C (p < 0.05). R+ may have a more favorable effect on oxidation processes according to the better MDA values in fresh meat (p < 0.001) and samples after 1–2 months of storage (p < 0.05) than R when compared with C. The negative modifications in the color parameters (L*, a*, and b*) and the organoleptic properties of the meat were less significant with R+ than R, compared to the control (p < 0.05). According to the results of this study, the R+ treatment was able to reduce the antinutritional effects of rapeseed, as evident from the properties of the resulting animal products.

A relatively novel approach for easy and quick determination of rutin in buckwheat grain is suggested. The rutin content of the grain in seven common buckwheat (Fagopyrum esculentum) and six Tartary buckwheat (Fagopyrum tataricum) varieties was investigated by means of UV photoacoustic spectroscopy and HPLC as reference method. The lowest content was found in ‘Botan’ and ‘Bamby’ varieties, while the highest values were obtained in the variety ‘Emka’. Rutin content in grain of all Tartary buckwheat varieties was two orders of magnitude higher than in the other varieties. Rutin content in F. esculentum ranges between 9 and 36 mg/100 g dry weight as compared to 921 to 2 132 mg/100 g dry weight in F. tataricum. The UV photoacoustic spectroscopy data show rather good correlations of R²=0.977 and R²=0.980 with values obtained by HPLC data for all measured samples. Therefore, UV photoacoustic spectroscopy can be a cheap and quick method for determining rutin content in buckwheat grain.

Fruit juices are widely consumed for their nutritional value and sensory appeal, but concerns regarding quality, adulteration and authenticity necessitate reliable, rapid and non-destructive analytical techniques. This review explores applications of UV-Visible spectroscopy (UV-Vis), infrared spectroscopy, fluorescence spectroscopy and Raman spectroscopy in fruit juice analysis. Literature was retrieved from Scopus, Web of Science and Google Scholar using predefined search terms. The working principles, instrumentation, and performance of these techniques are discussed, UV-Vis detection of pomegranate juice adulteration ( R ² up to 0.99), NIR prediction of Ca (RPD = 3.92), and ATR-FTIR sugar quantification ( R ² > 0.99). Applications include detecting and quantifying nutrients, adulterants, toxic elements and verifying quality attributes such as color, phenolic content and acidity. Integration with chemometrics and Artificial Intelligence (AI) enhances accuracy and predictive power, while miniaturization and multimodal approaches enable real-time, in-field monitoring. Despite challenges such as matrix effects and calibration complexity, optical spectroscopy shows strong potential for ensuring fruit juice safety, quality and authenticity.

Az élelmiszeriparban, különösen a gabonafeldolgozás területén, az élelmiszerek nyomonkövethetősége kiemelkedő jelentőséggel bír a minőségbiztosítás és az élelmiszerbiztonság szempontjából. A gabonatételek tárolása során az egyik legnagyobb kihívást a tételek hatékony elkülönítése és pontos lokalizálása jelenti. Az optikai módszerek, mint például a színképelemzés és a közeli infravörös (NIR) spektroszkópia, ígéretes megoldásokat nyújtanak e problémák kezelésére. Ebben a tanulmányban a CIELAB színrendszer alkalmazásával vizsgáltuk a gabonatételek tárolás közbeni keveredésének mértékét és a színbeli eltérések változását. A kutatás célja annak meghatározása volt, hogy a színjellemzők kombinált mutatójaként a HUE × C* mutató alapján milyen pontossággal lehet számszerűsíteni az egyes keveredési arányokat. Az általunk alkalmazott módszer lehetővé tette a színbeli változások objektív értékelését és a keveredések arányának meghatározását. Kísérleteink során beraktározott búzamintáknál azt vizsgáltuk, hogy hol helyezkedik el az a pont, ahol már nincs keveredés az egyes tételek között. A színméréseket D65 fényforrással felszerelt reflexiós koloriméter segítségével végeztük és minden mintát tíz ismétlésben vizsgáltunk. Az eredmények alátámasztották, hogy adott távolságra a gabonatételek keveredése már nem kimutatható. Az eredmények értékes információkat nyújtanak a gabonatételek lokalizációjához és a keveredési arány pontos szabályozásához síkraktárakban történő tárolás esetén.

Food rheology studies how food and beverages flow and deform. Milk and dairy products often contain multiple ingredients and structures that create a complex rheological response. This article aims to thoroughly review the rheological characteristics of various dairy products (milk, concentrated milk, fermented dairy gels, foams and cream, ice cream, butter, and low-fat dairy desserts), focusing on how the composition of dairy mixtures and processing parameters influence their rheological behavior and texture changes. Additionally, the study discusses the most commonly used rheological measurements and instruments in the dairy industry. Results show that measurements like texture profile analysis and fundamental methods, such as small amplitude oscillatory shear (SAOS), large amplitude oscillatory shear (LAOS), and tribology, provide more accurate information than empirical methods like gelometers and penetrometers. However, the colloidal properties and clumping behavior of dairy systems should be considered when choosing the appropriate rheological measurement technique. The study also highlights the trend of using hydrocolloids to improve the texture of dairy gels, especially low-fat dairy desserts, through casein-hydrocolloid linkages. Furthermore, it discusses how adding plant-based ingredients like coffee powder, flaxseed powder, and apple polyphenols in functional dairy products impacts their rheological properties, pointing to future improvements in product quality. Findings show that the interaction between dairy proteins and phenolic compounds significantly influences the texture and sensory qualities of functional dairy products enriched with plant extracts.