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Aim: Representatives of Nepetoideae Burnett subfamily are promising species of the Lamiaceae Martinov family because of accumulating such valuable groups of secondary metabolites as terpenoids and polyphenols. A high-performance thin layer chromatography (HPTLC) fingerprint method for the qualitative determination of phenolic compounds and for the quantification of rosmarinic acid (RA) content in methanol extracts of five species of this subfamily was developed for the first time. Materials and Methods: Dried aerial parts of Dracocephalum moldavica L., Ocimum americanum L., Lophanthus anisatus (Nutt.) Benth., Monarda fistulosa L., and Satureja hortensis L. collected in flowering period were macerated with methanol. The HPTLC analysis was conducted using the CAMAG analytical system (Muttenz, Switzerland). The comparative analysis of RA contents was performed by HPTLC densitometric detection at λ = 366nm. Results: Identification of polyphenols in the investigated herbs was performed by comparison of a color and Rf of the chromatographic zones with six reference standards: rutin, apigenin, luteolin, caffeic acid, chlorogenic acid, and RA. HPTLC method was also validated for the quantification of RA in the extracts of investigated herbs. RA contents decreased in such a sequence: D. moldavica (24.83 ± 0.78mg/g) > M. fistulosa (20.32 ± 0.64mg/g) > O. americanum (19.59 ± 0.61mg/g) > S. hortensis (18.77 ± 0.52mg/g) > L. anisatus (12.61 ± 0.43mg/g). Conclusion: Obtained data can facilitate the differentiation of investigated species using the chromatographic fingerprints of their phenolic compounds. Developed and validated HPTLC method provides an approach to estimate RA content as a common marker of investigated herbs.

Currently, there is no technology for the storage of green coffee (GrC), that results in obtaining high-quality roasted coffee (RC). The aim of this study was to evaluate the effects of storage temperature (− 10, 5, 10, 18, 20 °C), postharvest treatment method (natural (N), washed (W)) and type of packaging material (GrainPro (G), jute (J) bags) on the content of chlorogenic acids (CQAs), caffeine and trigonelline as well as the sensory profile of RC from the specialty sector after 12 months of regulated storage. Sensory analysis showed that natural coffees have better taste and higher quality than washed coffees after 12 months of storage. The highest total scores were obtained from the natural coffee stored in a GrainPro bag at − 10 °C followed by coffee stored in a jute bag at 10 °C which had the smallest decreases compared to the initial recorded values. No notable differences among CQA contents in washed coffees stored in either type of bag was seen but natural coffees stored in jute bags at 10 °C and 18 °C displayed the lowest drops relative to the initial values.

Cold brewing coffee has gained increasing popularity as a novel brewing method. A completely different flavour profile during cold brewing extraction (smooth and mild) is a result of the low-energy process, prolonged water-grind contact times and long preparation time. The aim of our research was to compare coffee drinks obtained with an innovative device for a faster, dynamic cold coffee extraction process (Hardtank) to drinks prepared traditionally in 24 h and hot brewed drinks. This study investigated the differences in chemical composition (volatile, non-volatile and lipid compounds), sensory properties and antioxidant capacity of coffee drinks from various extraction processes carried out at variable brewing temperatures, times and percolation modes. The results showed that the new cold maceration technique using coffee bed percolation (Hardtank) improved the quality of cold coffee drinks, making them similar in taste to hot coffee drinks. Among the studied extractions, the combination of a lower temperature (19.3 °C) and percolation process appeared to be the ideal setting for the most efficient extraction of compounds such as chlorogenic acids, gallic acid, caffeine, trigonelline, 5-(hydroxymethyl)furfural and lipids and consequently for their intake. In addition, FTIR spectra indicated an even 4 times greater quantity of lipids in Hardtank drinks than in classic cold brew and up to 5 times more lipids than in hot brew coffee, which contribute to the formation of the aroma and flavour. The decreased extraction time and use of coffee bed percolation could be beneficial for the quality and taste of cold brew products.

Honey is a natural product with a complex chemical composition consisting of sugars and other bioactive compounds. It is important in many traditional systems of medicine, exhibiting interesting bioactivities, in particular antimicrobial, anti-inflammatory and antioxidant effects. Authentication of botanical origin of honeys is particularly important in this context. Therefore, methods for quality control of honey and detection of its adulteration are very important. A HPTLC method for the quantitative determination of phenolic compounds in honey was developed for the first time. Seven phenolic compounds were detected and determined quantitatively in lime and acacia honey samples. The obtained results show that the HPTLC profiles of phenolic compounds and abscisic acid can be useful for determining the floral origin of honeys. Chromatographic tests were supplemented by statistical analysis (PCA and HCA) led to the successful separation of acacia and lime honey samples.

The growing interest in the quality of honey affects customer preferences and consumption trends. Generally, monofloral honeys are more expensive than multifloral honeys, and the price strictly depends on its botanical origin. The increasing popularity of a variety of monofloral brands has led to the increasing number of adulterations and therefore for the need to develop new analytical methods for assessing honey authenticity. The purpose of the present study was to develop a method for the authentication of phacelia honeys on the basis of HPLC and HPTLC analyses and spectrophotometry. The results obtained by spectrophotometric analysis indicated significant differences only between one sample and remaining ones of phacelia honeys. The application of HPLC and HPTLC methods allowed the complete differentiation of Phacelia tanacetifolia honey samples in context of content of other plants pollen. Thus, honeys containing more than 45% pollen from Phacelia tanacetifolia appear to exert more similarities in their respective chromatograms, while the chromatograms of two samples (Ph1 and Ph9), which derived from honey containing majority of pollen from other plants, differed significantly. Therefore, the combination of HPLC and HPTLC fingerprints supported by spectrophotometric measurements seems to be a suitable method for the classification of honey samples.

The present study reveals the utility of high-performance thin-layer chromatographic (HPTLC) fingerprinting of phenolic constituents for the authentication of monofloral honeys. The obtained data enables a more complete assessment of honey quality and the identification of emerging threats to honey quality. The developed procedure facilitates differentiation of varietal honeys and detection of honey adulterations. We used an HPTLC fingerprint analysis to determine the characteristic patterns of different honey types (willow, buckwheat, heather, pine honeydew, and manuka honey). The HPTLC chromatograms were used to determine the differences in the botanical origin of the honey samples on the basis of the band profiles, which are characteristic for each honey type. Identification of 11 polyphenols was performed by comparison of the color and R f of the bands with available standards. Additionally, the results were confirmed by an HPLC analysis.

A case study of Polish Melilotus officinalis honey was presented for the first time. Gas chromatography–mass spectrometry (GC-MS) (after steam distillation, Soxhlet extraction, ultrasonic solvent extraction, and solid phase extraction (SPE)) and targeted high performance liquid chromatography with a photodiode array detector (HPLC-PAD) were applied to determine the characteristic components of honey. While ubiquitous in most honeys, carbohydrates, terpene derivatives, and phenylacetic acid dominated in the Soxhlet extracts (25.54%) and in the application of SPE (13.04%). In addition, lumichrome (1.85%) was found, and may be considered as a marker of this honey. Due to the presence of these compounds, Polish yellow sweet clover honey is similar to French lavender honeys. The major compounds determined in the methanolic extract were (+)-catechine (39.7%) and gallic acid (up to 30%), which can be regarded as specific chemical markers of the botanical origin of melilot honey. With respect to total phenolic and flavonoid contents, 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. The honey exhibited a moderate antioxidant activity, typical for light honeys, which correlates well with its phenolic and flavonoid composition.