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Certain food by-products, including not-good-for-sale apples and pomegranate peels, are rich in bioactive molecules that can be collected and reused in food formulations. Their extracts, rich in pectin and antioxidant compounds, were obtained using hydrodynamic cavitation (HC), a green, efficient, and scalable extraction technique. The extracts were chemically and physically characterized and used in gluten-free and vegan cookie formulations to replace part of the flour and sugar to study whether they can mimic the role of these ingredients. The amount of flour + sugar removed and replaced with extracts was 5% and 10% of the total. Physical (dimensions, color, hardness, moisture content, water activity), chemical (total phenolic content, DPPH radical-scavenging activity), and sensory characteristics of cookie samples were studied. Cookies supplemented with the apple extract were endowed with similar or better characteristics compared to control cookies: high spread ratio, similar color, and similar sensory characteristics. In contrast, the pomegranate peel extract enriched the cookies in antioxidant molecules but significantly changed their physical and sensory characteristics: high hardness value, different color, and a bitter and astringent taste. HC emerged as a feasible technique to enable the biofortification of consumer products at a real scale with extracts from agri-food by-products.

Extra virgin olive oil (EVOO) is a valuable product and is highly appreciated by consumers for its great nutritional value. However, to date, there has been a lack of uniform systems capable of ranking the nutritional value of EVOO based on its chemical composition in terms of macro- and micronutrients (including phenolic compounds and tocopherols). The aim of this study was to propose a scoring algorithm to rank the nutritional value of EVOO samples, considering their chemical composition in macro- and micronutrients and their sensitivity to oxidation phenomena. Data from more than 1000 EVOO samples were used to assess the variability of the data, considering the selected negative parameters (free acidity, peroxide value, spectrophotometric indices) and positive components (composition in tocopherols via HPLC-DAD, phenolic compounds via HPLC-DAD, and fatty acids via GC-MS) so as to ensure the universal validity of the scoring algorithm. The dataset included samples from the main producing countries worldwide, in addition to Australia, across several production years; data were selected to represent different production realities. A mathematical model was set up for each chemical component, resulting in six variable values. By combining these values with a dimensionless constant value, the algorithm for computing the nutritional value score (NVS) was defined. It allows the nutritional value of an oil to be ranked on a scale of 0 to 100 based on its chemical composition. The algorithm was then successfully tested using chemical data from about 300 EVOO samples obtained from laboratories from different Italian regions. The proposed NVS is a simple and objective tool for scoring the nutritional value of an EVOO, easy to understand for both producers and consumers.

Olives are very rich in phenolic compounds with important health-promoting properties. The profile and content of phenols in olive pulp and virgin olive oil are strongly influenced by the fruit ripening degree, but little is known concerning the evolution of phenolic compounds in the seed. In this work, the phenolic composition of seed from Tuscan cultivars (Frantoio, Moraiolo, Leccino) was studied over maturation. Starting from each seed sample, a phenolic extract was prepared and analyzed by HPLC-DAD-MS. Nüzhenide and nüzhenide 11-methyl oleoside were by far the most abundant phenolic compounds; their content reached up to 46 g/kg in dry seeds, although this diminished in the final stage of fruit maturation. At the same time, the phenolic composition of the pulp was also characterized over the course of maturation, showing that oleuropein was by far the most abundant compound, with concentrations comparable to those of nüzhenide and nüzhenide 11-methyl oleoside in the seeds. Overall, the total amount of phenols in seed dry extracts was significant, reaching approx. 100 g/kg. The chemically characterized dry phenolic extracts from seeds could be used for future biological assays aimed at evaluating the potential bioactivities of these phytocomplexes.

Oenotannins are nowadays widely used as co-adjuvant in the winemaking process. The increasing cultivation and consumption of pomegranate (Punica granatum L.) leads to high amounts of by-products, mainly peels. Aim of this study was to propose a dried tannin-rich extract from pomegranate by-products as a new oenotannin. A decoction was prepared from mesocarp of the Wonderful pomegranate variety only using hot water as extracting solvent. The dried decoction was physical-chemically characterized and compared to 7 existing commercial oenotannins from different botanical origin (grape seed, oak, gallnut), according to UV-Vis Spectroscopy, Colorimetric analysis (CIELab), gelatin index, reactivity to proteins, HPLC-DAD, DPPH, and Total Polyphenols content by both Folin-Ciocalteu and the International Organization of Vine and Wine (OIV) methods. Data showed the lowest antiradical (AR) and total polyphenolic content (TPC) for the pomegranate tannin but also the highest AR/TPC ratio suggesting a good radical scavenging potential of this new tannin. Pomegranate tannin showed high reactivity with proteins, a unique chromatographic profile, and a low color impact. The new pomegranate tannin showed an interesting potential for oenological applications in particular for reducing the use of sulfites during vinification and for the white wine stabilization.

The beneficial properties of phenolic compounds from Olea europaea L. are well-known. An olive extract (OE) was prepared from unripe olives (Moraiolo cultivar). The study aimed to formulate OE into a microemulsion (ME) in oral dosage form. OE was extracted from olives with EtOH:H2O (80:20) and characterized by HPLC-DAD. ME composition was stated by a solubility and pseudo-ternary diagram. The ME was chemically and physically characterized, and its stability at 4 °C was analyzed for three months. The ability of the formulation to ameliorate the solubility and the intestinal permeability of OE was evaluated by a Parallel Artificial Membrane Permeability Assay (PAMPA) assay and Caco-2 cells. The total phenolic content of the extract was 39% w/w. The main constituent was oleuropein (31.0%), together with ligstroside (3.1%) and verbascoside (2.4%). The ME was prepared using Capryol 90 as the oily phase, and Cremophor EL and Transcutol (2:1) as surfactant and co-surfactant, respectively. ME droplet size was 14.03 ± 1.36 nm, PdI 0.20 ± 0.08, ζ-potential −1.16 ± 0.48. Stability of ME was confirmed for at least three months. The formulation was loaded with 35 mg/mL of OE, increasing the solubility of the extract by about four times. The enhanced permeability of OE was evaluated by PAMPA, as demonstrated by the Pe value (1.44 ± 0.83 × 10−6 cm/s for OE hydroalcoholic solution, 3.74 ± 0.34 × 10−6 cm/s for OE-ME). Caco-2 cell transport studies confirmed the same results: Papp was 16.14 ± 0.05 × 10−6 cm/s for OE solution and 26.99 ± 0.45 × 10−6 cm/s for OE-ME. ME proved to be a suitable formulation for oral delivery.

The characterization of six varieties of native Andean potatoes with a wide biodiversity in tuber shape, flesh, and skin color was performed, through the determination of their proximate composition, mineral content, and phenolic profile. Minerals concentration revealed significant genotypic variation. Potassium was the most abundant element in all varieties, ranging from 7272.9 to 13,059.9 µg/g and from 12,418 to 17,388.6 µg/g dried weight for the flesh and skin samples, respectively. Iron content was relevant, ranging from 20.5 to 39.9 µg/g and from 112.2 to 288.8 µg/g dried weight in flesh and skin samples, respectively. Phenolic compounds were consistently higher in the skin than in the flesh. The total content varied greatly from 19.5 to 2015.3 µg/g and from 1592.3 to 14807.3 µg/g dried weight for flesh and skin tissues, respectively. 5-caffeoylquinic acid was 74% of the total phenolic acids. Different pattern of anthocyanins was found, depending on the color of the variety; the red genotypes contained predominantly pelargonidin derivatives, while the purple samples had petunidin as a major anthocyanidin. This study increases the knowledge of the composition of the local Andean varieties (which are only scarcely studied so far), helping to enhance these genotypes and the conservation of biodiversity.

Onion is widely used worldwide in various forms for both food and medicinal applications, thanks to its high content of phytonutrients, such as flavonoids and volatile sulfur compounds. Fresh onion is very perishable and drying is widely applied for extending shelf-life, thus obtaining a very easy-to-use functional food ingredient. The flavonoid and volatile fractions of different onion cuts (flakes, rings) prepared through different drying cycles in a static oven, were characterized by high-performance liquid chromatography with a diode-array detector HPLC-DAD, Head Space-Solid Phase Micro Extraction followed by Gas Chromatography coupled with Mass Spectrometry (HS-SPME-GC-MS) and Head-Space Solid Phase Micro Extraction followed by comprehensive two-dimensional Gas-Chromatography (HS-SPME-GC×GC-TOF). Onion flakes showed a significantly higher flavonoid content (3.56 mg g−1) than onion rings (2.04 mg g−1). Onion flakes showed greater amount of volatile organic compounds (VOCs) (127.26 mg g−1) than onion rings (42.79 mg g−1), with different relative amounts of di- and trisulfides—disulfides largely predominate the volatile fraction (amounts over 60% on the total volatile content), followed by trisulfides and dipropyl disulfide and dipropyl trisulfide were the most abundant VOCs. HS-SPME-GC×GC-TOF allowed for the detection of the presence of allylthiol, diethanol sulfide, 4,6-diethyl1,2,3,5-tetrathiolane, not detected by HS-SPME-GC-MS, and provided a fast and direct visualization and comparison of different samples. These results highlight different nutraceutical properties of dried onion samples processed otherwise, only differing in shape and size, thus pointing out potentially different uses as functional ingredients.

The health claims of olive oil represent an important marketing lever in raising the willingness to pay for a product, but world producers of extra virgin olive oil (EVOO) do not take advantage of it because there are still obstacles to their use. Among these, one issue is the lack of an official method for determination of all free and linked forms derived from secoiridoidic structures of hydroxytyrosol and tyrosol. In this study, different acidic hydrolytic procedures for analyzing the linked forms were tested. The best method was validated and then applied to more than 100 EVOOs. The content of oleuropein and ligstroside derivatives in EVOOs was indirectly evaluated comparing the amount of phenols before and after hydrolysis. After acidic hydrolysis, a high content of total tyrosol was found in most of the EVOOs. The use of a suitable corrective factor for the evaluation of hydroxytyrosol allows an accurate determination only using pure tyrosol as a standard. Further knowledge on the concentration of total hydroxytyrosol will assist in forecasting the resistance of oils against aging, its antioxidant potential and to better control its quality over time.

The use of innovative systems, such as the heat exchanger, for production of extra virgin olive oil should allow maintenance of the same quality of those oils derived from traditional processes, and presents specific advantages. The performance of this system was evaluated by (i) determining the parameters directly measurable by the olive millers (i.e., end-user validation based on the production yields when the plant is located in different processing lines) and (ii) assessing the product quality through estimation of the content of phenolic and volatile compounds. The phenols were determined by High Performance Liquid Chromatography with Diode Array Detector (HPLC−DAD) before and after acidic hydrolysis while the volatile fraction was studied by Head-Space Solid-Phase-Micro-Extraction Gas-Chromatography with Mass Detector (HS−SPME−GC−MS). The use of the sono-heat-exchanger presents several advantages: it is a flexible machine, able to interface with all devices of the world’s leading manufacturers of the Extra Virgin Olive Oil (EVOO) extraction plant, and it guarantees shorter processing times and energy savings. Our results also pointed out its capability to increase the oil yields up to 5.5%, particularly when it extracts oil from unripe fruits, which in traditional processes yield oils with higher phenolic contents, but with lower oil yields. Overall, the quality of virgin olive oils was maintained, avoiding decreases of phenolic content or detrimental effects on the sensory characteristics.

Essential oils are widely used as functional ingredients for potential multi-purpose functional uses. Hydrosols, co-products of the distillation of plant material, are used in food and cosmetic industries and in biological agriculture, but their volatile composition is poorly investigated. The volatile fractions of essential oils and hydrosols from four less-studied 1,8-cineol-rich Eucalyptus species (E. parvula L.A.S. Johnson & K.D. Hill, E. cinerea F. Muell, E. pulverulenta Sims and E. pulverulenta baby blue Sims), cultivated in Tuscany in a system of organic farming, were characterized by solvent dilution (essential oils) or extraction (hydrosols) followed by GC-MS and by HS-SPME-GC×GC-TOFMS analysis. GC-MS analysis showed that essential oils were mainly constituted by oxygenated monoterpenes, particularly 1,8-cineole, with monoterpenes hydrocarbons up to 10.8%. Relative differences in the abundance of minor terpenes as limonene, α-pinene, γ-terpinene, p-cymene, terpinen-4-ol, α-terpineol, and alloaromandrene were pointed out and seem to be suitable for differentiation among EOs of the four different Eucalyptus species. Hydrosols of these species were characterized for the first time: they were mainly constituted by oxygenated monoterpenes (97.6–98.9%), with 1,8-cineole up to 1.6 g/L, while monoterpene and sesquiterpene hydrocarbons were detected only in traces. HS-SPME-GC×GC-TOFMS analysis also allowed providing metabolic profiling of hydrosols for the direct comparison and visualization of volatile components, pointing out the potentially different uses of these products as functional ingredients in food, beverage, and cosmetic industries.