Effect of Innovative Food Processing Technologies on the Physicochemical and Nutritional Properties and Quality of Non-Dairy Plant-Based Beverages.

Increase in allergenicity towards cow's milk, lactose intolerance, the prevalence of hypercholesterolemia, and flexitarian choice of food consumption have increased the market for cow's milk alternatives. Non-dairy plant-based beverages are useful alternatives because of the presence of bioactive components with health-promoting properties, which attract health-conscious consumers. However, the reduced nutritional value and sensory acceptability of the plant-based beverages (such as flavor, taste, and solubility) compared to cow's milk pose a big threat to its place in the market. Thermal treatments are commonly used to ensure the quality of plant-based beverages during storage. However, the application of high temperatures can promote the degradation of thermolabile compounds and some detrimental reactions, thus reducing protein digestibility and amino acid availability of non-dairy plant-based beverages substitutes. New and advanced food processing technologies, such as high-pressure processing, high-pressure homogenization, pulsed electric fields, and ultrasound, are being researched for addressing the issues related to shelf life increase, emulsion stability, preservation of nutritional content and sensorial acceptability of the final product. However, the literature available on the application of non-thermal processing technologies on the physicochemical and nutritional properties of plant-based beverages is scarce. Concerted research efforts are required in the coming years in the functional plant-based beverages sector to prepare newer, tailor-made products which are palatable as well as nutritionally adequate.

Evaluating the impact of supercritical-CO2 pressure on the recovery and quality of oil from "horchata" by-products: Fatty acid profile, α-tocopherol, phenolic compounds, and lipid oxidation parameters.

The effect of supercritical carbon dioxide (SC-CO2) (10-40 MPa) and conventional extraction (CE) to recover oil from by-products obtained during "horchata" production was assessed. To evaluate both extraction techniques, the fatty acid composition, polyphenols, α-tocopherol, antioxidant capacity and lipid oxidation parameters of the extracts obtained were analysed. A linear relationship between extraction pressure and oil yield was observed. However, the highest oil yield was obtained under conventional extraction. The by-products from "horchata" presented a profile where monounsaturated fatty acids (MUFA) were the predominant, representing ≈ 70% of total fatty acids. The amount of saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA) was higher and MUFA lower at 10 MPa samples compared to the oils extracted using SC-CO2 at 20, 30 or 40 MPa, where no differences were detected. The content of α-tocopherol was significantly higher after SC-CO2 treatments compared to conventional extraction, independently of the applied treatment. On the other hand, the values of phenolic compounds and total antioxidant activity (TAC) increased as the pressure conditions of the SC-CO2 extraction increased, presenting a linear adjustment of the data. Regarding lipid oxidation, the lower oxidation indexes were obtained when the SC-CO2 pressure increased. Finally, our results confirmed that the application of SC-CO2 could be a potential alternative to conventional extraction in order to obtain oils from "horchata" by-products rich in high-added value compounds without the use of organic solvents which can be toxic.

Influence of Temperature, Solvent and pH on the Selective Extraction of Phenolic Compounds from Tiger Nuts by-Products: Triple-TOF-LC-MS-MS Characterization.

The aim of this study was to assess the effect of temperature, solvent (hydroethanolic mixtures) and pH on the recovery of individual phenolic compounds from "horchata" by-products. These parameters were optimized by response surface methodology and triple-TOF-LC-MS-MS was selected as the analytical tool to identify and quantify the individual compounds. The optimum extraction conditions were 50% ethanol, 35 °C and pH 2.5, which resulted in values of 222.6 mg gallic acid equivalents (GAE)/100 g dry matter and 1948.1 µM trolox equivalent (TE)/g of dry matter for total phenolic content (TPC) and trolox equivalent antioxidant capacity (TEAC), respectively. The extraction of phenolic compounds by the conventional solvent method with agitation was influenced by temperature (p = 0.0073), and more strongly, by the content of ethanol in the extraction solution (p = 0.0007) while the pH did not show a great impact (p = 0.7961). On the other hand, the extraction of phenolic acids was affected by temperature (p = 0.0003) and by ethanol amount (p < 0.0001) but not by the pH values (p = 0.53). In addition, the percentage of ethanol influenced notably the extraction of both 4-vinylphenol (p = 0.0002) and the hydroxycinnamic acids (p = 0.0039). Finally, the main individual phenolic extracted with hydroethanolic mixtures was 4-vinylphenol (303.3 µg/kg DW) followed by spinacetin3-O-glucosyl-(1→6)-glucoside (86.2 µg/kg DW) and sinensetin (77.8 µg/kg DW).

Phenolic profile of oils obtained from "horchata" by-products assisted by supercritical-CO2 and its relationship with antioxidant and lipid oxidation parameters: Triple TOF-LC-MS-MS characterization.

In this study, the effect of different supercritical CO2 (SC-CO2) pressures (10-40 MPa) on phenolic compounds extraction in oils obtained from "horchata" by-products was evaluated, and the results were compared to those obtained after conventional oil extraction (CE). Moreover, the relationship between the individual phenolic compounds and the total antioxidant capacity as well as oil oxidative quality parameters was compared. The phenolic profile and contents were largely influenced by extracting conditions. The main phenolic compound obtained by SC-CO2 was the isohydroxymatairesinol, particularly at 30 and 40 MPa, while 3-vinylphenol was the predominant compound in oils extracted by CE procedure. Increasing SC-CO2 extraction pressures enhanced the extraction of phenolic compounds, along with improving the antioxidant capacity and oxidative quality of extracted oil. The principal component analysis indicated that the main phenolic compounds associated with TEAC values were those extracted by SC-CO2, which were inversely correlated to oxidative indexes.

Enhancing Bioactive Antioxidants' Extraction from "Horchata de Chufa" By-Products.

During the production of a traditional drink produced from the tubers of Cyperus esculentus L. also known as "horchata de chufa," a high quantity of by-products are generated. These by-products are rich with valuable biological compounds, hence, there is a need to report their extraction conditions for further use in food production as raw materials. Therefore, the objective of this study was to evaluate and improve the conventional extraction process, applied for recovery of phenolic compounds, total flavonoids, and total antioxidant capacity from the by-products. Independent variables for extraction were: (i) Solvent type (mixtures of ethanol-water (v/v) at 0%, 25% and 50%); (ii) temperature (40, 50 and 60 °C), and (iii) extraction time (1, 2 and 3 h). The obtained results showed that solvent type, temperature, and time significantly influenced (p < 0.05) all investigated parameters. The highest content of total polyphenols (16.02 mg GAE/100 g of dry matter; d.m.), and total flavonoids (30.09 mg CE/100 g d.m.) was achieved by ethanol at 25% (v/v), after 3 h of extraction with temperatures of 60 °C and 50 °C, respectively. The highest value of antioxidant capacity (1759.81 µM Trolox equivalents/g d.m.) was observed with 50% aqueous ethanol (v/v), at 60 °C, and 3 h of extraction. From the obtained results, it can be concluded that the by-products of "Horchata de Chufa" are an important source of antioxidant bioactive compounds.

Thermal and non-thermal preservation techniques of tiger nuts' beverage "horchata de chufa". Implications for food safety, nutritional and quality properties.

"Horchata de chufa" is a traditional Spanish beverage produced from tiger nuts (Cyperus esculentus L.). Due to its richness in nutritional compounds, it is highly perishable and its conservation by pasteurization and/or adding preservatives is required. Although efficient, conventional thermal treatment for pasteurization induces changes in the nutritional and sensory properties. Replacing conventional pasteurization by non-thermal technologies such as pulsed electric fields, ultraviolet, and high pressure, combined with moderate temperatures (<40°C) allows a reduction of energy consumption, along with the preservation of the most thermo-sensitive molecules. Accordingly, this review deals with the description of the most relevant non-thermal technologies applied to preserve "horchata" beverage in order to extend the shelf life and inactivate pathogenic microorganisms as well as to preserve the nutritional and quality properties of this food beverage.

Current and New Insights in the Sustainable and Green Recovery of Nutritionally Valuable Compounds from Stevia rebaudiana Bertoni.

The South American plant Stevia rebaudiana Bertoni is a great source of noncaloric sweeteners (steviol glycosides), mainly concentrated in its leaves, but also has important antioxidant compounds (vitamin C, polyphenols, chlorophylls, and carotenoids) and other important macro- and micronutrients such as folic acid and all of the essential amino acids except tryptophan. Traditionally, conventional methods have been used to recover nutritionally valuable compounds from plant food matrices. However, nowadays, the need for obtaining greener, sustainable, and viable processes has led both food industries and food scientists to develop new processes in full correspondence with the green extraction concept. This review focuses on some of the most promising nonconventional and emerging technologies, which may constitute a potential alternative to conventional methods or even could be combined to obtain a synergistic effect, thus reducing extraction time as well as solvent consumption and avoiding the use of toxic solvents.