Research background. Herbs and spices used in traditional medicine are nowadays increasingly used in combinations to create functional food formulations aimed at treating specific symptoms and ...disorders. Among herbs originating from the Mediterranean region, extracts of myrtle (Myrtus communis L.), bay leaf (Laurel nobilis L.) and fennel (Foeniculum vulgare Mill.) are traditionally used for gastrointestinal disorders. When considering how to incorporate these extracts into products, dairy-free milk alternatives provide an excellent base with almond-based drinks being among the most popular within this group.
Experimental approach. The aim of this study is therefore to optimise the formulation of an almond drink fortified with a 25 % (on dry mass basis) aqueous herbal extract containing myrtle, bay leaf (25 % each) and fennel seed (50 %) extracts. A central composite design with 20 formulations varied the content of φ(aqueous herbal extract)=2–6 %, lecithin as emulsifier 0.15–0.45 and xylitol as sweetener 2–5 % (m/V), while antioxidant activity, total phenolic content and sensory properties were determined as dependent variables.
Results and conclusions. The antioxidant activity and total phenolic content of the prepared almond drink formulations increased with the amount of added concentrated aqueous herbal extracts, as did the colour, herbal odour and flavour, bitterness and aftertaste. The addition of lecithin resulted in a darker colour and the sweetness was increased by the xylitol content. All formulations had good overall attractiveness, which increased with higher xylitol content.
Novelty and scientific contribution. The current work offers new insights into the optimisation of fortified dairy-free alternatives. The addition of myrtle, bay leaf and fennel seed extracts to almond drink-based formulations resulted in a 12-fold increase in antioxidant activity. Xylitol masks the potential bitterness of the phenolic compounds so that higher amounts of extracts can be added.
The objective was to evaluate the influences of the high hydrostatic pressure extraction parameters on the recovery of anthocyanins from the grape skin pomace extracts (Vitis vinifera cv. Teran) ...under moderate temperatures. Studied parameters were: solvents (methanol and ethanol); solvent concentrations (30, 50, and 70%); pressures (300, 400, and 500 MPa); times (3, 6.5, 10 min); and temperatures (22, 26, 30 °C). Predominant anthocyanins in all extracts were malvidins (malvidin‐3‐glucoside as the main compound) representing 55.77% of overall anthocyanin content. The type of solvent did not significantly influence anthocyanin extraction yield, while decreased solvent concentration (increased solvent‐to‐water ratio) significantly improved extraction of anthocyanins. Increase of pressure enhanced extraction yield of the anthocyanins but temperature showed stronger impact on the anthocyanins recovery. This investigation evidenced that the best conditions for HHPE of anthocyanins from grape pomace were extraction time 3.39 min, extraction temperature 29.48 °C, pressure 268.44 MPa and solvent concentration 70%.
Practical applications
Due to increased interest for the use of cheap winery byproducts as a source of expensive polyphenols for functional food production, skins from grape pomace became valuable raw material. Therefore, there is a need to evaluate the influence of HHPE innovative extraction technology on its nutritive value during processing. Optimizing parameters for polyphenolic recovery from grape pomace is directly related with nutritional value and economics of food engineering during industrial processing. Obtained results showed that the HHPE under lower temperatures is suitable for the extraction process of anthocyanins from grape skin pomace, but more research is needed to identify other food‐grade solvents with their corresponding concentrations that are useful for the extraction assisted with high hydrostatic pressure.
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•The functional beveragesare excellent delivering means for nutrients and bioactive molecules.•Use of medicinal and aromatic plants in the production of functional beverages has ...become increasingly popular due to specific content ofstructurally diverse bioactive molecules withnumerous confirmed healthbenefitsand specific sensory properties.•The quality of plant extracts and essential oils depends on quality of raw materials and applied extraction techniques.•Rising consumer demand for natural ingredients provides numerous opportunities for the fortification and development of new categories of functional beverages based on medicinal and aromatic plants.
The functional beverages (FBs) are an important segment of functional food products due to health benefits they provide and their appealing sensory characteristics, suitability and affordability. FBs market offers many opportunities for new product development (nutraceuticals, colorants, plant-based medicines and products) with desirable and effective composition ofnutrients and bioactive molecules (BAMs) aimed to deliver health benefits and improve human well-being. Recently, the use of medicinal and aromatic plants (MAPs) in the production of FBs has become increasingly popular due to specific content of nutrients (amino and fatty acids) and BAMs (volatile and non-volatile) attributed to the biological effects and health benefits. BAMs are stored in leaves, flowers, fruits, seeds, barks and roots, and they mostly include phenolics (phenolic acids, flavonoids, tanins, anthocyanins, lignans and stilbenes), essential oils (EOs), terpenoids, alkaloids, phytosterols and saponins. The aromatic features of MAPs are mainly related to volatile compounds of EOs, but the presence of non-volatile compounds, such as phenolics, also contributes to the specific sensory properties. Phytochemical profiling of plant species containing specific and complex mixtures of BAMs, provides numerous opportunities for the development of new categories of FBs, but also opens new challenges in their isolation using conventional and advanced extraction techniques, as well as determination of potential biological effects. This review summarizes the categories of the most common FBs, BAMs from selected MAPs and their biological effects, extraction techniques suitable for production of plant extracts and EOs, product quality and prediction trends, and several directions towards future research on FBs development strategies.
This research was undertaken to investigate the influence of extraction parameters during microwave-assisted extraction on total phenolic content, total flavonoids, total hydroxycinnamic acids and ...total flavonols of blackthorn flowers as well as to evaluate the antioxidant capacity by two different methods (2,2-diphenyl-1-picrylhydrazyl free radical scavenging capacity and ferric reducing antioxidant power assays). The investigated extraction parameters were: solvent type and volume fraction of alcohol in solvent (50 and 70% aqueous solutions of ethanol and methanol), extraction time (5, 15 and 25 min) and extraction temperature (40, 50 and 60 °C) controlled by microwave power of 100, 200 and 300 W. Multivariate analysis of variance (MANOVA) was used to evaluate the differences at a 95% confidence level (p≤0.05). The obtained results show that aqueous solution of ethanol was more appropriate solvent for extraction of phenolic compounds (total flavonoids, total hydroxycinnamic acids and total flavonols) than aqueous solution of methanol. The amount of phenolic compounds was higher in 70% aqueous solution of ethanol or methanol, while higher antioxidant capacity was observed in 50% aqueous solution of methanol. Higher temperature of extraction improved the amount of phenolic compounds and also antioxidant capacity determined by 2,2-diphenyl-1-picrylhydrazyl free radical scavenging capacity assay. Extensive duration of extraction (15- to 25-minute interval) has a significant effect only on the increase of total phenolic content, while specific phenolic compound content and antioxidant capacity were the highest when microwave extraction time of 5 min was applied.
Objectives were to evaluate and optimize single and cumulative influences of extraction times (30, 45, 60 min) and acidity (0, 0.5, 1% of HCl) on quantities of total polyphenols (TP), hydroxycinnamic ...acids (HCA) and antioxidant capacity (AC) extracted from red grape skin pomace extracts (Vitis vinifera, cv. Merlot). Increasing time and acidity increased TP, HCA and AC. Highest quantities of TP, HCA and AC were at 1% HCl and between 45 and 60 min. Time had little influence on amounts of polyphenols without HCl. For most of extraction times, AC followed similar trends as studied polyphenols. AC remained constant between 30 and 45 min for low concentrations of HCl. Calculated optimal extraction conditions for: HCA = 7.93 mg/g dry pomace, t = 60 min, HCl = 0.84%; TP = 99.99 mg/g dry pomace, t = 60 min, HCl = 0.79%; DPPH = 2,055.75 mg/100g were t = 60 min and HCl = 0.77%. All variables (TP, HCA and AC) strongly increased as a function of each other. Constructed mathematical models retained these relations.
Practical Applications
Interest for the use of winery byproducts as a source of polyphenols in industrial production is steadily increased over the last decade. Extracted polyphenols from such materials can be successfully added to the functional foods and provide substantial economic benefits for food industry along with nutritive foods. Therefore, optimizing all possible parameters for polyphenolic recovery (such as acidity and time) from grape pomace are directly related with economic and nutritional cost‐benefits of industrial processing.
Since certain constituents are not naturally present in pure fruit juices, incorporating herbal extracts can provide specific sensory properties to the beverages and improve their biopotential. In ...our previous research, it was found that sage (
L.), wild thyme (
L.), and combinations of their extracts had the highest total phenolic content and a unique composition of volatile compounds, which can contribute to the aromatic and antioxidant qualities of functional products. Therefore, this research aimed to investigate the potential of sage and wild thyme extracts, as well as their mixture (wild thyme:sage at 3:1,
/
), to enrich fruit juices (apple, pineapple, and orange). Obtained beverages were evaluated for sensory properties as well as phenolic and headspace composition (UPLC-MS/MS and HS-SPME/GC-MS analysis) and antioxidant capacity (ORAC assay). The incorporation of wild thyme extract in pineapple juice provided the most harmonious flavor and the highest content of volatile compounds (on PDMS/DVB fiber). The orange juice formulations were the most enriched with phenolic and volatile compounds (on DVB/CAR/PDMS fibers). The highest antioxidant capacity was observed in the formulation with orange juice and sage extract (22,925.39 ± 358.43 µM TE). This study demonstrated that enriching fruit juices with sage and wild thyme extracts could create functional beverages with improved sensory and health-promoting properties, providing valuable insights for the food and beverage industry to meet the growing demand of health-conscious consumers for natural and functional products.
The aim of the present study was to evaluate microwave-assisted (MAE) and pressurized liquid extraction (PLE) for the recovery of polyphenols from blackcurrant and bilberry leaves and the ...preservation of their antioxidant activity. The extractions were carried out varying the solvent/solid (SS) ratio, temperature and time. During MAE, increasing the SS ratio increased the polyphenol concentration in the extracts from blackcurrant and bilberry leaves, while increasing the temperature had a positive effect only on bilberry polyphenols. During PLE, only a temperature increase was a determining factor for the isolation of blackcurrant leave polyphenols. Based on polyphenol recovery, optimal extraction parameters were established resulting in a yield of 62.10 and 56.06 mg/g dw in the blackcurrant and bilberry MAE extracts and 78.90 and 70.55 mg/g dw in the PLE extracts. The optimized extracts were profiled by UPLC ESI MS
, and their antioxidant capacity was evaluated through FRAP, DPPH, ABTS and ORAC assays. The characterization of the extracts by UPLC ESI MS
confirmed flavonols as the predominant compounds in both blackcurrant and bilberry leaves, while flavan-3-ols and procyanidins were the main compounds responsible for high antioxidant capacity as confirmed by the ABTS and ORAC assays. Due to the extract composition and antioxidant capacity, PLE proved to be a technique of choice for the production of blackcurrant and bilberry leave extracts with high potential for use as value-added ingredients in the food and nutraceutical industry.
In the present study, advanced extraction techniques, microwave (MAE), ultrasound (UAE), and high pressure (HPAE)-assisted extraction, were applied to improve extraction efficiency of olive (Olea ...europaea L.) leaves polyphenols. The effect of sample mass (1.5 and 3 g), MAE—time (2, 8.5, and 15 min) and temperature (45 and 80 °C), UAE—time (7, 14, and 21 min) and amplitude (50 and 100%) and HPAE—time (1, 5.5, and 10 min) and pressure (300 and 500 MPa) on the concentration of each analyzed polyphenol compound was examined. Identified polyphenols were oleuropein, hydroxytyrosol, chlorogenic acid, caffeic acid, verbascoside, and rutin. All three advanced extraction techniques yielded higher content of total polyphenols when compared to the conventional heat-reflux extraction (CE) along with a significant reduction of extraction time from 60 (CE) to 2, 21, and 5.5 min in MAE, UAE, and HPAE, respectively. The most intensive values of tested parameters in each technique were the ones that promoted cell wall disruption, e.g., temperature of 80 °C in MAE, 100% amplitude in UAE and 500 MPa in HPAE. MAE and UAE were more efficient in total polyphenols’ recovery than HPAE.
This study evaluated the presence of bioactives in wild nettle leaves and stalks during the phenological stage and in the context of natural habitat diversity. Thus, wild nettle samples collected ...before flowering, during flowering and after flowering from 14 habitats situated in three different regions (continental, mountain and seaside) were analyzed for low molecular weight polyphenols, carotenoids and chlorophylls using UPLC-MS/MS and HPLC analysis, while the ORAC method was performed for the antioxidant capacity measurement. Statistical analysis showed that, when compared to the stalks, nettle leaves contained significantly higher amounts of analyzed compounds which accumulated in the highest yields before flowering (polyphenols) and at the flowering stage (pigments). Moreover, nettle habitat variations greatly influenced the amounts of analyzed bioactives, where samples from the continental area contained higher levels of polyphenols, while seaside region samples were more abundant with pigments. The levels of ORAC followed the same pattern, being higher in leaves samples collected before and during flowering from the continental habitats. Hence, in order to provide the product's maximum value for consumers' benefit, a multidisciplinary approach is important for the selection of a plant part as well as its phenological stage with the highest accumulation of bioactive compounds.
The opportunity of tomato peel waste exploitation for simultaneous recoveries of high value compounds, such as pectin, polyphenols and fatty acids (FAs) is presented in this work. Prior to ...polyphenols and FAs extraction, the pectin removed from tomato cuticle was evaluated as possible tin corrosion inhibitor using electrochemical impedance spectroscopy. Subsequently, de-pectinized tomato peels are evaluated as appropriate bio-substrate for polyphenols and FAs recovery, using chromatographic analyses. Corrosion tests (24 h) showed that pectin (4 g/L) isolated from tomato peel act as more efficient tin corrosion inhibitor (
η
= 65.8%) than commercial apple pectin (
η
= 52.3%), which points out that it could be used as natural corrosion inhibitor. The polyphenols data showed that de-pectinized samples contained higher amounts of total phenols (2485.68–4064.46 mg/100 g, in 96% ethanol) and chlorogenic acid derivative (86.13–454.34 109 mg/100 g, in 70% ethanol) than samples with pectin incorporated in tomato cuticle. In addition, de-pectinized samples contained more polyunsaturated FAs (~ 45%) than samples with pectin (~ 26). Furthermore, both types of peels contained linoleic, palmitic and oleic acids as three dominants, and thus represented valuable source of nutritive oils. Their presence was also confirmed by FTIR and NMR spectroscopy. Therefore, obtained findings revealed that already exploited tomato peel for pectin production could be effectively re-used for polyphenols and FAs recoveries, providing valuable benefits, either for producers and consumers, such as decreasing the waste disposal costs and take opportunity that isolated compounds could be reintroduced into food.
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