A comprehensive review on carotenoids in foods and feeds: status quo, applications, patents, and research needs.

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.

Effects of Maltodextrins on the Kinetics of Lycopene and Chlorogenic Acid Degradation in Dried Tomato.

Maltodextrins (MD) are frequently used as processing aids in tomato drying. The aim of this study was to investigate the effect of the addition of MD on the stability of lycopene and chlorogenic acid, which are the main lipophilic and hydrophilic antioxidants in processed tomato, respectively. Tomato powder added with 10% MD (dextrose equivalents, DE 12) and a control tomato powder were stored in the water activity (aw) range 0.17⁻0.56, for 180 d at 30 °C. At the aw level of 0.17, which was below the monolayer moisture content (Mo), chlorogenic acid was stable, while lycopene content decreased faster in tomato added with MD than in control tomato, probably due to a decrease in matrix hydrophilicity and greater oxygen diffusion in the oil phase. Maximum stability occurred in both tomato powders at aw of 0.3, that was in close proximity to Mo (first-order rate constant for lycopene, k = 7.0 × 10-3 d-1 in tomato added with MD). At high aw levels, MD increased the rate of lycopene degradation with respect to the control, possibly by hampering its regeneration by chlorogenic acid, which conversely was found to be more stable than in the control tomato.

Grape skin extracts from winemaking by-products as a source of trapping agents for reactive carbonyl species.

BACKGROUND: Clinical evidence supports the relationship between carbonyl stress and type II diabetes and its related pathologies. Methylglyoxal (MGO) is the major dicarbonyl compound involved in carbonyl stress. Efforts are therefore being made to find dietary compounds from natural sources that could exert an MGO trapping response. RESULTS: The in vitro MGO trapping capacity of six red and seven white grape skin extracts (GSE) obtained from winemaking by-products was investigated. Methanolic GSE exhibited a promising MGO trapping capacity that was higher in red GSE (IC50 2.8 mg mL(-1)) when compared with white GSE (IC50 3.2 mg mL(-1)). The trapping ability for red GSE correlated significantly with total phenolic content and antioxidant capacity. However, no correlations were observed for white GSE, which suggests that other compounds were involved in the trapping activity. CONCLUSION: GSE may be considered a natural source of carbonyl stress inhibitors, thus opening up its possible utilization as a nutraceutical ingredient. Further investigations are required to understand the mechanism involved in the carbonyl trapping ability of red and white grape skin samples and their relationship with glycation.

Hydration and Fortification of Common Bean (Phaseolus vulgaris L.) with Grape Skin Phenolics-Effects of Ultrasound Application and Heating.

Ultrasound (US)-assisted soaking combined with fortification with red grape skin (GS) phenolics was applied on two Phaseolus varieties, namely White Kidney Bean (WKB) and Cranberry Bean (CB), before heat treatment. The aims were to investigate: (a) the effect of US application on the kinetic of hydration; (b) the extent of absorption of different phenolic classes of GS into the beans and the resulting effect on antioxidant activity; (c) the effects of heat treatment on the phenolic fraction and antioxidant activity of GS extract- and water-soaked beans. US fastened the soaking step of both WKB and CB beans, which showed the sigmoidal and the downward concave shape hydration curves, respectively. Anthocyanins, flavonols, flavanol and phenolic acids levels increased with GS soaking, but US application was effective only for increasing the level of flavonols, while it favored the loss of endogenous phenolic acids and it did not affect the uptake of anthocyanins and flavanols. Heat treatment decreased the levels of most of phenolic compounds, but increased the levels of monomeric flavanols. Overall, the antioxidant activity was 40% higher in WKB and 53% higher in CB upon GS-fortification than in the control beans, despite the effects of heating. This fortification strategy could be applied for value addition of varieties low in phenolics or as a pre-treatment before intensive processing.

Application of inulin for the formulation and delivery of bioactive molecules and live cells.

Inulin is a fructan biosynthesized mainly in plants of the Asteraceae family. It is also found in edible vegetables and fruits such as onion, garlic, leek, and banana. For the industrial production of inulin, chicory and Jerusalem artichoke are the main raw material. Inulin is used in the food, pharmaceutical, cosmetic as well biotechnological industries. It has a GRAS status and exhibits prebiotic properties. Inulin can be used as a wall material in the encapsulation process of drugs and other bioactive compounds and the development of their delivery systems. In the review, the use of inulin for the encapsulation of probiotics, essential and fatty oils, antioxidant compounds, natural colorant and other bioactive compounds is presented. The encapsulation techniques, materials and the properties of final products suitable for the delivery into food are discussed. Research limitations are also highlighted.

Binary Alginate-Whey Protein Hydrogels for Antioxidant Encapsulation.

Encapsulation of antioxidants in hydrogels, i.e., three-dimensional networks that retain a significant fraction of water, is a strategy to increase their stability and bioaccessibility. In fact, low oxygen diffusivity in the viscous gelled phase decreases the rate of oxidation. Moreover, some hydrocolloids such as alginate and whey proteins provide a pH-dependent dissolution mechanism, allowing the retention of encapsulated compounds in the gastric environment and their release in the intestine, where they can be absorbed. This paper reviews the information on alginate-whey protein interactions and on the strategies to use binary mixtures of these polymers for antioxidant encapsulation. Results showed that alginate and whey proteins strongly interact, forming hydrogels that can be modulated by alginate molecular mass, mannuronic acid: guluronic acid ratio, pH, Ca2+ or transglutaminase addition. Hydrogels of alginate and whey proteins, in the forms of beads, microparticles, microcapsules, and nanocapsules, generally provide better encapsulation efficiency and release properties for antioxidants with respect to the hydrogel of alginate alone. The main challenges for future studies are to extend knowledge on the interactions among three components, namely alginate, whey proteins, and the encapsulated bioactive compounds, and to investigate the stability of these structures under food processing conditions. This knowledge will represent the rationale basis for the development of structures that can be tailored to specific food applications.

Kinetic Study of Encapsulated ß-Carotene Degradation in Aqueous Environments: A Review.

The provitamin A activity of ß-carotene is of primary interest to address one of the world's major malnutrition concerns. ß carotene is a fat-soluble compound and its bioavailability from natural sources is very poor. Hence, studies have been focused on the development of specific core/shell micro- or nano-structures that encapsulate ß-carotene in order to allow its dispersion in liquid systems and improve its bioavailability. One key objective when developing these structures is also to accomplish ß-carotene stability. The aim of this review is to collect kinetic data (rate constants, activation energy) on the degradation of encapsulated ß-carotene in order to derive knowledge on the possibility for these systems to be scaled-up to the industrial production of functional foods. Results showed that most of the nano- and micro-structures designed for ß-carotene encapsulation and dispersion in the water phase provide better protection with respect to a natural matrix, such as carrot juice, increasing the ß-carotene half-life from about 30 d to more than 100 d at room temperature. One promising approach to increase ß-carotene stability was found to be the use of wall material, surfactants, or co-encapsulated compounds with antioxidant activity. Moreover, a successful approach was the design of structures, where the core is partially or fully solidified; alternatively, either the core or the interface or the outer phase are gelled. The data collected could serve as a basis for the rational design of structures for ß-carotene encapsulation, where new ingredients, especially the extraordinary natural array of hydrocolloids, are applied.

Kinetic Study of Encapsulated ß-Carotene Degradation in Dried Systems: A Review.

ß-Carotene serves as a precursor of vitamin A and provides relevant health benefits. To overcome the low bioavailability of ß-carotene from natural sources, technologies have been designed for its encapsulation in micro- and nano-structures followed by freeze-drying, spray-drying, supercritical fluid-enhanced dispersion and electrospraying. A technological challenge is also to increase ß-carotene stability, since due to its multiple conjugated double bonds, it is particularly prone to oxidation. This review analyzes the stability of ß-carotene encapsulated in different dried micro- and nano-structures by comparing rate constants and activation energies of degradation. The complex effect of water activity and glass transition temperature on degradation kinetics is also addressed, since the oxidation process is remarkably dependent on the glassy or collapsed state of the matrix. The approaches to improve ß-carotene stability, such as the development of inclusion complexes, the improvement of the performance of the interface between air and oil phase in which ß-carotene was dissolved by application of biopolymer combinations or functionalization of natural biopolymers, the addition of hydrophilic small molecular weight molecules that reduce air entrapped in the powder and the co-encapsulation of antioxidants of various polarities are discussed and compared, in order to provide a rational basis for further development of the encapsulation technologies.

Vitamin D Incorporation in Foods: Formulation Strategies, Stability, and Bioaccessibility as Affected by the Food Matrix.

Inadequate intake of vitamin D is a global health issue related to severe diseases, mainly involving subjects with dark skin pigmentation, patients affected by malnutrition, malabsorption syndromes, or obesity, and elderly people. Some foods fortified with vitamin D have been tested in vivo, but fortification strategies with a global outreach are still lacking. This review is focused on food fortification with vitamin D, with the aim to collect information on (a) formulation strategies; (b) stability during processing and storage; and (c) in vitro bioaccessibility. Approaches to add vitamin D to various foods were analyzed, including the use of free vitamin D, vitamin D loaded in simple and double nanoemulsions, liposomes, casein micelles, and protein nanocapsules. Numerous studies were reviewed to elucidate the impact of food technologies on vitamin D's stability, and mechanisms that lead to degradation were identified-namely, acid-catalyzed isomerization, radical-induced oxidation, and photo-oxidation. There is, however, a lack of kinetic data that allow for the prediction of vitamin D's stability under industrial processing conditions. The roles that lipids, proteins, fibers, and antioxidants play in vitamin bioaccessibility have been clarified in various studies, while future needs include the design of specific food matrices that simultaneously achieve a balance between the long-term stability, bioaccessibility and, ultimately, in vivo functionality of vitamin D.

Carotenoids: Considerations for Their Use in Functional Foods, Nutraceuticals, Nutricosmetics, Supplements, Botanicals, and Novel Foods in the Context of Sustainability, Circular Economy, and Climate Change.

Carotenoids are versatile isoprenoids that are important in food quality and health promotion. There is a need to establish recommended dietary intakes/nutritional reference values for carotenoids. Research on carotenoids in agro-food and health is being propelled by the two multidisciplinary international networks, the Ibero-American Network for the Study of Carotenoids as Functional Foods Ingredients (IBERCAROT; http://www.cyted.org) and the European Network to Advance Carotenoid Research and Applications in Agro-Food and Health (EUROCAROTEN; http://www.eurocaroten.eu). In this review, considerations for their safe and sustainable use in products mostly intended for health promotion are provided. Specifically, information about sources, intakes, and factors affecting bioavailability is summarized. Furthermore, their health-promoting actions and importance in public health in relation to the contribution of reducing the risk of diverse ailments are synthesized. Definitions and regulatory and safety information for carotenoid-containing products are provided. Lastly, recent trends in research in the context of sustainable healthy diets are summarized.

The Effect of UV Irradiation on Vitamin D2 Content and Antioxidant and Antiglycation Activities of Mushrooms.

Mushroom irradiation has been considered a sustainable process to generate high amounts of vitamin D2 due to the role of this vitamin for human health and of the global concerns regarding its deficient or inadequate intake. Mushrooms are also receiving increasing interest due to their nutritional and medicinal properties. However, there is still a knowledge gap regarding the effect of UV irradiation on mushroom bioactive compounds. In this study, two of the most cultivated mushroom species worldwide, Agaricus bisporus and Pleurotus ostreatus, were irradiated with UV-B, and the effect of processing was investigated on the contents of vitamin D2 as well as on antioxidant and antiglycation activities. UV irradiation increased vitamin D2 up to 57 µg/g d.w, which is an adequate level for the fortification of a number of target foods. UV irradiation decreased the antioxidant activity when measured by the Folin-Ciocalteu reagent, the 2,2-diphenyl-1-(2,4,6 trinitrophenyl) hydrazyl radical assay and the ferric ion-reducing antioxidant power assay, but did not decrease the mushroom's ability to inhibit glycation of a target protein. These results open up a new area of investigation aimed at selecting mushroom species with high nutraceutical benefits for irradiation in order to maintain their potential properties to inhibit oxidative and glycation processes responsible for human diseases.

Impact of Pleurotus ostreatus ß-Glucans on Oxidative Stability of Active Compounds Encapsulated in Powders during Storage and In Vitro Digestion.

Polyunsaturated fatty acids and α-tocopherol were encapsulated in powders by spray drying using maltodextrins DE 12 as wall material and different emulsifiers (Tween®20, acacia gum or ß-glucans-rich extracts from Pleurotus ostreatus). The aim was to study the effects of the surfactants on: (a) the oil droplet size distribution and α-tocopherol stability during in vitro digestion, and (b) the oxidative stability during 15 days of accelerated storage. Acacia gum sample had the most stable particle size distribution up to the gastric phase, but showed a significant α-tocopherol degradation prior to the intestinal stage. On the contrary, ß-glucan-samples displayed a bimodal distribution in the oral and gastric phases but retained α-tocopherol up to the beginning of the intestinal stage. At the end of intestinal stage, no α-tocopherol was found in the samples. The storage study showed that ß-glucans improved the oxidative stability of the powders, which displayed 82% α-tocopherol retention after 5 days under accelerated conditions (60 °C), corresponding to 310 days at 20 °C, while acacia gum and Tween® 20 did not delay α-tocopherol degradation. Results highlight the potential antioxidant activity of ß-glucans used as emulsifying agents during in vitro digestion and accelerated aging conditions.

Use of Grape Pomace Phenolics to Counteract Endogenous and Exogenous Formation of Advanced Glycation End-Products.

The increase in consumption of "ultra-processed" foods has raised attention because of the possible adverse effects deriving from the Maillard reaction leading to the formation of toxic advanced glycation end-products (AGEs) during food processing. Additionally, the increasing trend and consumption of sugar-added foods and sweetened beverages is related to the endogenous formation of the same toxic compounds. However, ultra-processing in the context of food technology can bring challenges as well as a wealth of opportunities. Indeed, re-processing of grape pomace, a by-product of winemaking, can yield phenolic-rich fractions that efficiently counteract the effects of AGEs. In this review, the process of endogenous and exogenous AGE formation is illustrated. Then, the ability of grape phenolics to act as inhibitors of AGE formation is presented, including the efficacy ranking of various individual compounds measured in vitro and the outcome of in vivo double-blinded randomized crossover trials designed to prove the efficacy of grape phenolics as inhibitors of protein carbonylation. Finally, a survey of model functional foods added with grape phenolics, either to lower the dietary load of AGEs or to deliver antiglycation agents in vivo is listed in order to highlight the opportunity to develop safe and tailor-made "anti-AGEs" food applications.

Acceptance of a New Food Enriched in ß-Glucans among Adolescents: Effects of Food Technology Neophobia and Healthy Food Habits.

The aim of the present study was to evaluate adolescents' acceptability of a novel flat bread modified by substituting a part of the wheat flour content with a Pleurotus ostreatus powder rich in ß-glucans, which can potentially provide health benefits. The effects of food technology neophobia and adolescents' food habits on hedonic perception of the developed product was also investigated. Two hundred and two adolescents (age range: 13-18 years; girls: 49.5%; boys: 50.5%) evaluated their liking of two flat breads, one with mushroom powder added and one control sample with only wheat flour. Sample acceptance was studied in relation to age, gender, neophobic traits and healthy food habits. The results showed that, even if the sample with mushroom powder added was generally well accepted, there were different hedonic responses among adolescents according to their food technology neophobia level and healthy habits. In particular, adolescents with a low food technology neophobia level and healthy eating behavior mostly appreciated the sample with mushroom powder added, whereas subjects with neophobic and unhealthy eating behavior gave comparable hedonic scores to the two samples. Moreover, a negative correlation was found between food technology neophobia level and healthy food habits. In conclusion, it is possible to develop a ß-glucan-enriched product appreciated by adolescents using a sustainable ingredient. The developed product may be used to achieve the daily recommended intake of ß-glucans by adolescents.

Effect of Pleurotus ostreatus powder addition in vegetable soup on ß-glucan content, sensory perception, and acceptability.

Pleurotus ostreatus is an edible mushroom with interesting nutritional properties, which is able to grow on agri-food waste and could in turn be used as an ingredient for food fortification. However, new food products have to face with the growing consumer consciousness about what they eat and hedonic responses, which represent a key factor in determining food preference and choices. The aim of this study was to design a vegetable-based product (a pumpkin and carrot soup) added with increasing concentration of P. ostreatus powder rich in ß-glucans, which are fibers with demonstrated bioactivity in humans, and to obtain a sensory description of these fortified products to find the desirable and undesirable sensory properties that affect their acceptance. A total of 109 subjects (women N = 52; men N = 57; age = 36.1 ± 14.4 years) evaluated five samples of pumpkin and carrot soup added with increasing concentrations of mushroom powder (0%, 2%, 4%, 6%, and a hidden control at 0%) for liking and sensory properties by means of the check-all-that-apply method. Results showed that creaminess, orange color, mild odor, and taste were positively related to vegetable soups liking, whereas strong taste, dark color, and mushroom odor described the less liked samples. Sample added with 2% of mushroom powder obtained comparable liking scores to the unmodified sample, while liking decreased with increasing concentration of P. ostreatus powder. The present results demonstrated that it is possible to fortify a vegetable soup with P. ostreatus powder developing well-accepted foods by consumers. This product could be used to implement an everyday dietary intervention of ß-glucans over a long-term period.

Effect of Vitamin D2 Fortification Using Pleurotus ostreatus in a Whole-Grain Cereal Product on Child Acceptability.

Vitamin D2 deficiency is one of the most common micronutrient insufficiencies among children. Few foods, mainly those derived from animal sources, naturally contain this vitamin. The basidiomycete mushroom Pleurotus ostreatus could be used as an innovative and sustainable ingredient for food fortification with vitamin D2. This study was aimed at exploring children's acceptance of a whole-cereal-based product (breadsticks) combined with increasing concentrations of P. ostreatus powder rich in vitamin D2. The food neophobia trait (fear of trying unfamiliar and new food) on sample acceptability was also investigated. One hundred and three children (47 girls and 56 boys, aged 9-11 years) were recruited, and breadstick-liking was studied in relation to gender and neophobic traits. Results showed that the samples enriched in vitamin D2 were well accepted by children even if liking decreased with increasing concentration of mushroom powder. Generally, neophilic subjects gave higher liking scores compared with the neophobic ones, especially for the modified samples. New, well-accepted fortified products could be developed using an adequate concentration of mushroom powder to deal with the increasing vitamin D2 deficiency among children.

Circular reuse of bio-resources: the role of Pleurotus spp. in the development of functional foods.

The basidiomycetes fungi belonging to the genus Pleurotus could make an important contribution to sustainable functional food design because they possess an elevated protein content with a valuable essential amino acid scoring pattern, a unique dietary fibre profile, mainly comprised of branched ß-glucan, high levels of some vitamins of the B group, vitamin D, Fe, Zn, Cu, Se and some bioactive mycochemicals, while the Na and fat contents are low. Moreover, Pleurotus spp. can grow efficiently on various clean by-products of food processing, such as wheat straw, wheat stalk and spent beer grain, thus representing a sustainable food source. This review illustrates the compositional variability of Pleurotus spp. grown on various by-products, in order to clarify its potential ability to address the needs of populations with endemic nutritional deficiencies as well as those populations at risk or affected by some chronic diseases. The perspectives for Pleurotus applications in functional foods decisively depend on consumers' acceptability. Hence, the sensory properties of Pleurotus spp. are also clarified herein. Lastly, the three main strategies of functional food development using Pleurotus spp. are summarized, namely its use as a fortifying agent, high-cost protein replacer and prebiotic ingredient.

Effect of storage on secoiridoid and tocopherol contents and antioxidant activity of monovarietal extra virgin olive oils.

The degradation of secoiridoid, tocopherol, and antioxidant activity in extra virgin olive oils (EVOOs) was studied during 8 months of storage in closed bottles in the dark, at 40 and 25 degrees C. Picual, Arbequina, Taggiasca, and Colombaia monovarietal EVOOs possessing quite different fatty acid and antioxidant contents were used. The secoiridoid aglycones, namely, the oleuropein and ligstroside derivatives, and alpha-tocopherol decreased following pseudo-first-order kinetics. In all EVOOs oleuropein derivatives were less stable than the corresponding ligstroside derivatives and alpha-tocopherol. Accordingly, overall antioxidant activity decreased following pseudo-first-order kinetics, with rate constants ranging from 0.85 x 10(-)(3) to 4.1 x 10(-)(3) days(-)(1) at 40 degrees C and from 0.8 x 10(-)(3) to 1.5 x 10(-)(3) days(-)(1) at 25 degrees C. According to both the antioxidant activity and the hydrolysis and oxidation indices established by EU regulation to assess EVOO quality, Colombaia oil was the least stable, followed by Taggiasca, Arbequina, and Picual oils. Despite antioxidant degradation, EVOOs with high antioxidant contents were still "excellent" after 240 days of storage at 40 degrees C. These data led to the conclusion that the beneficial properties of EVOOs due to antioxidant activity can be maintained throughout their commercial lives.

Waste grape skins: evaluation of safety aspects for the production of functional powders and extracts for the food sector.

Skin powders and aqueous alcohol extracts were obtained from waste marcs from different grape varieties (Barbera, Nebbiolo, Pinot Noir, Chardonnay, Moscato and Müller-Thurgau). Both skins and extracts were analysed for the content of chemical contaminants: ochratoxin A (OTA), biogenic amines (BIAs), pesticides and metals. OTA was detected in low concentrations in Barbera, Moscato and Nebbiolo skins, but only in Barbera and Moscato extracts. Cadaverine, putrescine, ethanolamine and ethylamine were found in extracts at very low levels, while potential allergenic amines, tyramine and histamine, were never detected. Different pesticides were present in both skins and extracts. Pb and Cd were found in trace only in the powders, and K, Ca and Mg were the most abundant elements in both skin powders and extracts. Concentrations of the different contaminants were related to fibre content or total phenolics content of powders and extracts, respectively, in order to evaluate their use in the food sector.

Secoiridoids, tocopherols, and antioxidant activity of monovarietal extra virgin olive oils extracted from destoned fruits.

The effect of olive stone removal before processing on the degradation level, secoiridoid and tocopherol contents, and antioxidant activity of monovarietal extra virgin olive oils (EVOOs) was studied. EVOOs were extracted from olives of the Leccino, Moraiolo, Frantoio, Pendolino, Taggiasca, and Colombaia varieties both in the presence and in the absence of the stones. The degradation level of EVOOs was evaluated by acidity, peroxide number, and spectroscopic indices K(232) and K(270), according to EU regulation. The secoiridoid compounds typical of EVOO, namely, the oleuropein and ligstroside derivatives, hydroxytyrosol, tyrosol, and tocopherols were analyzed by HPLC. The antioxidant activity was evaluated by the xanthine oxidase/xanthine system, generating superoxide radical and hydrogen peroxide, and by the 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl test. Results showed that EVOOs obtained from both stoned and destoned olives had a very low degradation level, which was not affected by destoning. Destoning lowered slightly the alpha-tocopherol content in EVOOs but increased the total secoiridoid content and the antioxidant activity of EVOOs (up to 3.5-fold). However, these effects were variety-dependent and negligible in some conditions. It was concluded that a better knowledge of the reactions occurring during olive processing, and particularly on the involvement of endogenous pulp and stone enzymes, is essential to predict the effect of destoning on EVOO quality.