Valorizations of Sweet Cherries Skins Phytochemicals by Extraction, Microencapsulation and Development of Value-Added Food Products

Innovative approaches to harnessing natural pigments from food waste and by-products for eco-friendly food coloring

With unprecedented growth in the world population, the demand for food has risen drastically leading to increased agricultural production. One promising avenue is recovery of value-added pigments from food waste which has been gaining global attention. This review focuses on sustainable strategies for extracting pigments, examining the factors that influence extraction, their applications, and consumer acceptability. The significant findings of the study state the efficiency of pigment extraction through innovative extraction techniques rather than following conventional methods that are time-consuming, and unsustainable. In addition to their vibrant colors, these pigments provide functional benefits such as antioxidant properties, extended shelf life and improved food quality. Societal acceptance of pigments derived from food waste is positively driven by environmental awareness and sustainability. The study concludes by highlighting the stability challenges associated with various natural pigments, emphasizing the need for tailored stabilization methods to ensure long-term stability and effective utilization in food matrices.

Development and study of the functional properties of marshmallow enriched with bee (Apis mellifera) honey and encapsulated probiotics (Lactobacillus rhamnosus)

Consumer demand for healthier confectionery products has prompted the confectionery industry to create products that are reduced in sugar content and supplemented with vitamins, antioxidants or biological elements beneficial to health. The aim of this study was to develop marshmallows enriched with Apis mellifera honey and Lactobacillus rhamnosus and to evaluate the effect of honey concentration and gelatin bloom degrees on marshmallow properties. A completely randomized design with a factorial structure was applied with different honey concentrations (0, 50 and 75%) and at different gelatin bloom degrees (265, 300 and 315 bloom degrees); moreover, the physicochemical properties, total phenol content and antioxidant activity of the marshmallow were studied, as well as the viability of the probiotic. The physicochemical properties of the marshmallows were found to be adequate and showed good stability over time. The concentration of honey and gelatin bloom degrees did not significantly affect probiotic viability. The density of the marshmallows decreased as the percentage of honey increased. Additionally, the pH was lower at higher honey concentrations. The marshmallow with 75% honey and 265 bloom degrees had a higher °Brix value. The honey treatments exhibited higher levels of total antioxidant activity and total phenolic compounds than the sugar-only marshmallows. However, the bloom degrees did not have a significant impact on the antioxidant activity and total phenolic compound content. Although the probiotics did not reach the minimum viability needed, their use as paraprobiotics can be considered.

Sustainable Valorization of Industrial Cherry Pomace: A Novel Cascade Approach Using Pulsed Electric Fields and Ultrasound Assisted-Extraction

In this study, a two-stage cascade extraction process utilizing pulsed electric fields (PEF) (3 kV/cm, 10 kJ/kg) for initial extraction, followed by ultrasound (US) (200 W, 20 min)-assisted extraction (UAE) in a 50% (v/v) ethanol-water mixture (T = 50 °C, t = 60 min), was designed for the efficient release of valuable intracellular compounds from industrial cherry pomace. The extracted compounds were evaluated for total phenolic content (TPC), flavonoid content (FC), total anthocyanin content (TAC), and antioxidant activity (FRAP), and were compared with conventional solid-liquid extraction (SLE). Results showed that the highest release of bioactive compounds occurred in the first stage, which was attributed to the impact of PEF pre-treatment, resulting in significant increases in TPC (79%), FC (79%), TAC (83%), and FRAP values (80%) of the total content observed in the post-cascade PEF-UAE process. The integration of UAE into the cascade process further augmented the extraction efficiency, yielding 21%, 49%, 56%, and 26% increases for TPC, FC, TAC, and FRAP, respectively, as compared to extracts obtained through a second-stage conventional SLE. HPLC analysis identified neochlorogenic acid, 4-p-coumaroylquinic, and cyanidin-3-O-rutinoside as the predominant phenolic compounds in both untreated and cascade-treated cherry pomace extracts, and no degradation of the specific compounds occurred upon PEF and US application. SEM analysis revealed microstructural changes in cherry pomace induced by PEF and UAE treatments, enhancing the porosity and facilitating the extraction process. The study suggests the efficiency of the proposed cascade PEF-UAE extraction approach for phenolic compounds from industrial cherry pomace with potential applications to other plant-based biomasses.

Application of ultrasound technology for the effective management of waste from fruit and vegetable

Food waste presents a continuous challenge for the food industry, leading to environmental pollution and economic issues. A substantial amount of waste, including by-products from fruits and vegetables, non-edible food items, and other waste materials, is produced throughout the food supply chain, from production to consumption. Recycling and valorizing waste from perishable goods is emerging as a key multidisciplinary approach within the circular bio-economy framework. This waste, rich in raw by-products, can be repurposed as a natural source of ingredients. Researchers increasingly focus on biomass valorization to extract and use components that add significant value. Traditional methods for extracting these bio-compounds typically require the use of solvents and are time-consuming, underscoring the need for innovative techniques like ultrasound (US) extraction. Wastes from the processing of fruits and vegetables in the food industry can be used to develop functional foods and edible coatings, offering protection against various environmental factors. This comprehensive review paper discusses the valorization of waste from perishable items like fruits and vegetables using US technology, not only to extract valuable components from waste but also to treat wastewater in the beverage industry. It also covers the application of biomolecules recovered from this process in the development of functional foods and packaging.

Research Progress on the Anticancer Activity of Plant Polysaccharides

Tumor is a serious threat to human health, with extremely high morbidity and mortality rates. However, tumor treatment is challenging, and the development of antitumor drugs has always been a significant research focus. Plant polysaccharides are known to possess various biological activities. They have many pharmacological properties such as immunomodulation, antitumor, antiviral, antioxidative, antithrombotic, and antiradiation effects, reduction of blood pressure and blood sugar levels, and protection from liver injury. Among these effects, the antitumor effect of plant polysaccharides has been widely studied. Plant polysaccharides can inhibit tumor proliferation and growth by inhibiting tumor cell invasion and metastasis, inducing cell apoptosis, affecting the cell cycle, and regulating the tumor microenvironment. They also have the characteristics of safety, high efficiency, and low toxicity, which can alleviate, to a certain extent, the adverse reactions caused by traditional tumor treatment methods such as surgery, radiotherapy, and chemotherapy. Therefore, this paper systematically summarizes the direct antitumor effects of plant polysaccharides, their regulatory effects on the tumor microenvironment, and intervening many common high-incidence tumors in other ways. It also provides data support for the administration of plant polysaccharides in modern tumor drug therapy, enabling the identification of new targets and development of new drugs for tumor therapy.

Food-grade encapsulated polyphenols: recent advances as novel additives in foodstuffs

A growing inclination among consumers toward the consumption of natural products has propelled the usage of natural compounds as novel additives. Polyphenols are among the most popular candidates of natural food additives with multiple functionalities and bioactivities but are limited by instability. In this regard, a series of food-grade encapsulated polyphenols has been tailored for incorporating into food formulations as novel additives, which could better satisfy the complicated industry processing. This review seeks to present the most recent discussions regarding their application status in diverse foodstuffs as novel additives, involving functionalities, action mechanisms, and relevant encapsulation technologies. The scientific findings confirm that such novel additives show positive effects on physicochemical, sensory, and nutritional properties as well as the shelf life of diverse food matrices. However, poor heat resistance is still the major defect that restricts their application in thermal processes. Future research should focus on the evaluation of the compatibility and applicability of encapsulated polyphenols in real food processes as well as track and deepen their molecular action mechanisms in the context of complex foodstuffs. Innovation of existing encapsulation technologies should also be concerned in the future to bridge the gap between lab and scale-up production.

Cryopreservation of bioflavonoid-rich plant sources and bioflavonoid-microcapsules: emerging technologies for preserving bioactivity and enhancing nutraceutical applications

Bioflavonoids are natural polyphenolic secondary metabolites that are medicinal. These compounds possess antitumor, cardioprotective, anti-inflammatory, antimicrobial, antiviral, and anti-psoriasis properties to mention a few. Plant species that contain bioflavonoids should be preserved as such. Also, the bioactivity of the bioflavonoids as neutraceutical compounds is compromised following extraction due to their sensitivity to environmental factors like light, pH, and temperature. In other words, the bioflavonoids' shelf-life is affected. Scientists noticed that bioflavonoids have low solubility properties, poor absorption, and low bioavailability following consumption. Researchers came up with methods to encapsulate bioflavonoids in order to circumvent the challenges above and also to mask the unpleasant order these chemicals may have. Besides, scientists cryopreserve plant species that contain bioflavonoids. In this review, we discuss cryopreservation and bioflavonoid microencapsulation focusing mainly on vitrification, slow freezing, and freeze-drying microencapsulation techniques. In addition, we highlight bioflavonoid extraction techniques, medicinal properties, challenges, and future perspectives of cryopreservation and microencapsulation of bioflavonoids. Regardless of the uniqueness of cryopreservation and microencapsulation as methods to preserve bioflavonoid sources and bioflavonoids' bioactivity, there are challenges reported. Freeze-drying technology is costly. Cryoprotectants damage the integrity of plant cells, to say the least. Researchers are working very hard to overcome these challenges. Encapsulating bioflavonoids via coaxial electrospray and then cryopreserving the micro/nanocapsules produced can be very interesting.

Food Wastes and Microalgae as Sources of Bioactive Compounds and Pigments in a Modern Biorefinery: A Review

The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries and society at large for the development of alternative solutions for synthetic and fossil fuel derived products, thus mitigating climate change and environmental hazards. Food wastes and microalgae have been studied for decades as potential sources of several compounds that could be employed in various fields of application from pharmaceutical to textile and packaging. Although multiple research efforts have been put towards extracting rich compounds (i.e., phenolic compounds, tocopherols, and tocotrienols) from these sources, they still remain overlooked as two major sources of bioactive compounds and pigments, mainly due to inefficient extraction processes. Hence, there is a growing need for the development of optimized extraction methods while employing non-organic solvent options following the main principles of green chemistry. This review will focus on delivering a clear and deep analysis on the existing procedures for obtaining bioactive compounds and pigments from food wastes derived from the most consumed and produced fruit crops in the world such as apples, oranges, cherries, almonds, and mangoes, and microalgal biomass, while giving light to the existing drawbacks in need to be solved in order to take full advantage of the rich properties present in these two major biorefinery sources.

Valorization of Bioactive Compounds from Two Underutilized Wild Fruits by Microencapsulation in Order to Formulate Value-Added Food Products

Currently, microencapsulation has become a viable method of nutrient delivery for the food industry. This work microencapsulated the bioactive compounds extracted from two neglected species (Balanites aegyptiaca and Ziziphus mauritiana) by freeze-drying. A combination of wall materials (whey protein and pectin; soy protein and maltodextrin) was chosen to prepare the microcapsules. The phytochemical and physicochemical characterization of the microcapsules was then carried out. The encapsulation yield ranged from 82.77% to 96.05% for Balanites and Ziziphus, respectively, whereas the efficiency was 76.18 ± 1.39% and 80.93 ± 1.71%. The stimulated in vitro gastrointestinal test showed that encapsulation increased the bioavailability of the bioactive compounds. The total carotenoids were the most bioavailable compounds with 85.89 ± 0.06% for Ziziphus and 70.46 ± 1.10% for Balanites, followed by total flavonoids for Zizyphus with 63.27 ± 1.56%. Furthermore, regardless of species or wavelengths, the HPLC analysis resulted in the identification of 17 bioactive metabolites. The predominant one was epicatechin, whose level ranged from 231.52 ± 5.06 to 250.99 ± 3.72 mg/100 g DW in Ziziphus and 91.80 ± 3.85 to 116.40 ± 4.09 mg/100 g DW in Balanites. In estimating the enzyme inhibition and antioxidant power, both studied fruits showed antidiabetic, inflammatory, and antioxidant effects. These findings suggest that natural bioactive compounds are abundant in the fruits of Z. mauritiana and B. aegyptiaca and could be a valuable source for the food and pharmaceutical industries.

Advancement of Protein- and Polysaccharide-Based Biopolymers for Anthocyanin Encapsulation

Although evidence shows that anthocyanins present promising health benefits, their poor stability still limits their applications in the food industry. Increasing the stability of anthocyanins is necessary to promote their absorption and metabolism and improve their health benefits. Numerous encapsulation approaches have been developed for the targeted release of anthocyanins to retain their bioactivities and ameliorate their unsatisfactory stability. Generally, choosing suitable edible encapsulation materials based on biopolymers is important in achieving the expected goals. This paper presented an ambitious task of summarizing the current understanding and challenges of biopolymer-based anthocyanin encapsulation in detail. The food-grade edible microencapsulation materials, especially for proteins and polysaccharides, should be employed to improve the stability of anthocyanins for effective application in the food industry. The influence factors involved in anthocyanin stability were systematically reviewed and highlighted. Food-grade proteins, especially whey protein, caseinate, gelatin, and soy protein, are attractive in the food industry for encapsulation owing to the improvement of stability and their health benefits. Polysaccharides, such as starch, pectin, chitosan, cellulose, mucilages, and their derivatives, are used as encapsulation materials because of their satisfactory biocompatibility and biodegradability. Moreover, the challenges and perspectives for the application of anthocyanins in food products were presented based on current knowledge. The proposed perspective can provide new insights into the amelioration of anthocyanin bioavailability by edible biopolymer encapsulation.

Ultrasound-Assisted Extraction of Natural Pigments From Food Processing By-Products: A Review

Ultrasound is an emerging technology, which has been highly explored in the food area to improve processes and products. When ultrasound is applied to a product with solid or fluid characteristics, the passage of acoustic waves and acoustic cavitation generates different mechanisms responsible for modifications in the original matrix of the sample. These effects of ultrasound can also be used to take advantage of by-products, for example by extracting compounds of interest, including natural pigments. Natural pigments or colorants are being highly demanded by different industries not only for color purposes but also due to their healthy properties, the greater demands in regulations and new consumer preferences. This review presents an updated critical analysis of the application of ultrasound-assisted extraction (UAE) to obtain natural pigments from food processing by-products. Initially, the ultrasound effects and mechanisms that improve the extraction of natural pigments in a fluid medium, as well as the factors that influence the extraction and the energy consumption of UAE are analyzed and described. Subsequently, the UAE application to obtain pigments belonging to the groups of carotenoids, chlorophyll, anthocyanins and betalains is evaluated. These sections detail the processing conditions, positive and negative effects, as well as possible applications of the extracted pigments. This review presents relevant information that may be useful to expand and explore new applications of ultrasound technology as well as promote the revaluation of by-products to obtain pigments that can be used in food, pharmaceutical or cosmetic industries.

In vitro assessment of the bioavailability of bioactive non-extractable polyphenols obtained by pressurized liquid extraction combined with enzymatic-assisted extraction from sweet cherry (Prunus avium L.) pomace

In vitro digestion and absorption simulation processes of non-extractable polyphenols (NEPs) obtained by pressurized liquid extraction combined with enzymatic-assisted extraction with Promod enzyme (PLE-EAE) from the residue of conventional extraction of sweet cherry pomace were studied. In general, total phenolic and proanthocyanidin contents decreased in each phase of the digestion. However, the antioxidant capacity increased when the digestion process progressed. In addition, the highest total phenolic and proanthocyanidin contents and antioxidant capacity were obtained in the absorbed fraction. NEPs from PLE-EAE extract, digestive fractions, absorbed and unabsorbed fractions were analyzed by ultra-high-performance liquid chromatography coupled to electrospray ionization quadrupole Exactive-Orbitrap mass spectrometry (UHPLC-ESI-Q-Orbitrap-MS). Fifteen NEPs were identified in the intestinal fraction and five in the absorbed fraction after the digestion process. Results obtained in this study define for the first time the bioavailability of antioxidant NEPs obtained from sweet cherry pomace.

Valorization of fruits and vegetable wastes and by-products to produce natural pigments

Synthetic pigments from petrochemicals have been extensively used in a wide range of food products. However, these pigments have adverse effects on human health that has rendered it obligatory to the scientific community in order to explore for much safer, natural, and eco-friendly pigments. In this regard, exploiting the potential of agri-food wastes presumes importance, extracted mainly by employing green processing and extraction technologies. Of late, pigments market size is growing rapidly owing to their extensive uses. Hence, there is a need for sustainable production of pigments from renewable bioresources. Valorization of vegetal wastes (fruits and vegetables) and their by-products (e.g. peels, seeds or pomace) can meet the demands of natural pigment production at the industrial levels for potential food, pharmaceuticals, and cosmeceuticals applications. These wastes/by-products are a rich source of natural pigments such as: anthocyanins, betalains, carotenoids, and chlorophylls. It is envisaged that these natural pigments can contribute significantly to the development of functional foods as well as impart rich biotherapeutic potential. With a sustainability approach, we have critically reviewed vital research information and developments made on natural pigments from vegetal wastes, greener extraction and processing technologies, encapsulation techniques and potential bioactivities. Designed with an eco-friendly approach, it is expected that this review will benefit not only the concerned industries but also be of use to health-conscious consumers.

Polyphenol Extraction by Different Techniques for Valorisation of Non-Compliant Portuguese Sweet Cherries towards a Novel Antioxidant Extract

Currently, there is special interest in the recovery of polyphenols from non-compliant fruits that have no market value; efforts to find value-added solutions for these food areas are a key option for a sustainable bio-economy. Saco cherries are a traditional Portuguese cherry variety, and although they are a nutritionally important food, rich in powerful dietary polyphenols, significant amounts of these cherries are not sold due to their small size. In this context, this work aimed to select the best method to produce novel antioxidant polyphenol-rich extracts from low calibre and non-compliant Saco cherries. Based on the results, microwaves-assisted extraction (MAE) allowed us to obtain a polyphenol-rich extract with a high antioxidant capacity (50.46 ± 1.58 mg Trolox equivalent (TE)/g dry extract (DE) by oxygen radical absorbance capacity (ORAC), 10.88 ± 0.38 mg ascorbic acid equivalent (AA)/g DE by 2-azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and 9.58 ± 0.42 mg TE/g DE by 2,2-diphenyl-1-picrylhydrazyl (DPPH)) and a high content of polyphenols, namely, hydroxycinnamic acids (neochlorogenic and p-coumaric acids) and anthocyanins (cyanidin-3-rutinoside and cyanidin-3-glucoside), compared with those of conventional extractions with low and high temperature and ultrasound-assisted extraction. The antioxidant extract produced from MAE could be a new alternative for the valorisation of non-compliant cherries since these extracts proved to be a functional ingredient due to the high content of antioxidants, which are linked to the prevention of diseases.