Spray-Drying of Antioxidant-Rich Blueberry Waste Extracts; Interplay Between Waste Pretreatments and Spray-Drying Process

Valorization of Food Waste to Produce Value-Added Products Based on Its Bioactive Compounds

The rapid growth of the global population and changes in lifestyle have led to a significant increase in food waste from various industrial, agricultural, and household sources. Nearly one-third of the food produced annually is wasted, resulting in severe resource depletion. Food waste contains rich organic matter, which, if not managed properly, can pose a serious threat to the environment and human health, making the proper disposal of food waste an urgent global issue. However, various types of food waste, such as waste from fruit, vegetables, grains, and other food production and processing, contain important bioactive compounds, such as polyphenols, dietary fiber, proteins, lipids, vitamins, organic acids, and minerals, some of which are found in greater quantities in the discarded parts than in the parts accepted by the market. These bioactive compounds offer the potential to convert food waste into value-added products, and fields including nutritional foods, bioplastics, bioenergy, biosurfactants, biofertilizers, and single cell proteins have welcomed food waste as a novel source. This review reveals the latest insights into the various sources of food waste and the potential of utilizing bioactive compounds to convert it into value-added products, thus enhancing people’s confidence in better utilizing and managing food waste.

Phenolic Fraction from Peanut (Arachis hypogaea L.) By-product: Innovative Extraction Techniques and New Encapsulation Trends for Its Valorization

Peanut skin is a by-product rich in bioactive compounds with high nutritional and pharmaceutical values. The phenolic fraction, rich in proanthocyanidins/procyanidins, is a relevant class of bioactive compounds, which has been increasingly applied as functional ingredients for food and pharmaceutical applications and is mostly recovered from peanut skins through low-pressure extraction methods. Therefore, the use of green high-pressure extractions is an interesting alternative to value this peanut by-product. This review addresses the benefits of the phenolic fraction recovered from peanut skin, with a focus on proanthocyanin/procyanidin compounds, and discusses the improvement of their activity, bioavailability, and protection, by methods such as encapsulation. Different applications for the proanthocyanidins, in the food and pharmaceutical industries, are also explored. Additionally, high-pressure green extraction methods, combined with micro/nanoencapsulation, using wall material derived from peanut industrial processing, may represent a promising biorefinery strategy to improve the bioavailability of proanthocyanidins recovered from underutilized peanut skins.

Wood Hemicelluloses as Innovative Wall Materials for Spray-Dried Microencapsulation of Berry Juice: Part 1—Effect of Homogenization Techniques on their Feed Solution Properties

The use of wood hemicelluloses, including galactoglucomannans (GGM) and glucuronoxylans (GX), in spray-dried microencapsulation of bioactive compounds has not been reported. Our study aims to investigate the benefits of spray-dried GGM and GX powders (sGGM and sGX) along with the effects of homogenization techniques (magnetic stirring, ultrasonication, and a combination of UltraTurrax homogenization and microfluidization) on the physicochemical properties of feed solutions (10–20%, w/w). Feed solutions of bilberry juice with sGGM, sGX, and mixtures of either sGGM or sGX with methylcellulose (MC) or carboxymethylcellulose (CMC) were examined to produce highly stable feed solutions for spray-dried microencapsulation. The effects of ultrasonication amplitudes (30–80%) on the viscosity and particle size distribution of sGGM feed solutions were more profound than observed in their sGX counterparts. Unlike sGX feed solutions, sGGM feed solutions homogenized by ultrasonication and microfluidization formed a gel-like structure. Microfluidization also caused a loss of total anthocyanin content (TAC) of the feed solutions. Magnetic stirring resulted in no gel formation and in the lowest viscosity of the feed solutions; hence, it is an effective method for preparing hemicellulose feed solutions. sGGM and sGX powders have high heat stability with melting temperatures of 170–180 °C. The sGGM + CMC combination was more stable over 1 week of storage than the sGGM and sGX feed solutions. Storing the feed solutions reduced TAC and increased sGGM viscosity. Our results indicated that GGM and GX have high potential for use as wall materials in the spray-dried microencapsulation of bioactive compounds.

A critical review on biomass-based sustainable biorefineries using nanobiocatalysts: Opportunities, challenges, and future perspectives

Biocatalysts, including live microbial cells/enzymes, have been considered a predominant and advantageous tool for effectively transforming biomass into biofuels and valued biochemicals. However, high production costs, separation, and reusability limit its practical application. Immobilization of single and multi-enzymes by employing different nano-supports have gained massive attention because of its elevated exterior domain and high enzymatic performance. Application of nanobiocatalyst can overcome the drawbacks mainly, stability and reusability, thus reflecting the importance of biomass-based biorefinery to make it profitable and sustainable. This review provides an in-depth, comprehensive analysis of nanobiocatalysts systems concerning nano supports and biocatalytic performance characteristics. Furthermore, the effects of nanobiocatalyst on waste biomass to biofuel and valued bioproducts in the biorefinery approach and their critical assessment are discussed. Lastly, this review elaborates commercialization and market outlooks of the bioconversion process using nanobiocatalyst, followed by different strategies to overcome the limitations and future research directions on nanobiocatalytic-based industrial bioprocesses.

Encapsulation of Bilberry Extract with Maltodextrin and Gum Arabic by Freeze-Drying: Formulation, Characterisation, and Storage Stability

Anthocyanins are polyphenolic plant pigments associated with antioxidant and health-promoting properties. However, their application in the food industry is limited due to their poor stability. The purpose of this study was to encapsulate anthocyanin-rich bilberry (Vaccinium myrtillus L.) extract by freeze-drying and to investigate the effects of different wall materials and extract contents on the physicochemical and bioactive properties of the obtained encapsulates. Ethanolic bilberry extract was encapsulated with the use of maltodextrin (16.5–19.5 DE) (MD), gum Arabic (GA), and their combination in a 1:1 w/w ratio (MIX). Bilberry solids to wall material ratios were examined at 20:80, 30:70, and 40:60. All encapsulates showed an attractive red colour and low water activity values (aw ≤ 0.3) that indicated a low risk of microbial spoilage. In general, the biggest losses of total phenolic compounds and anthocyanins during three-week storage in the dark and at room temperature (20 ± 2 °C) were detected in the case of encapsulates with a higher content of bilberry extract (MIX30 and MIX40, and GA30 and GA40, respectively). The use of maltodextrin provided the best protection to bilberry anthocyanins during forced storage. Overall, the obtained encapsulates show suitable potential for the development of food products with added nutritional benefits.

Phenolic Profiling of Berries Waste and Determination of Their Antioxidant Potential

Berries waste is a major issue in Australia’s annual food wastage, which can reach 7.3 million tonnes. This study assessed the phenolic content and antioxidant potential of four fruit berry wastes, including blueberries (Vaccinium corymbosum), blackberries (Rubus spp.), raspberries (Rubus idaeus), and strawberries (Fragaria spp.), followed by their characterization and quantification. Blueberry wastes were high in phenolic content (total phenolic content: 1.97 ± 0.16 mg GAE/gF.W; total flavonoid content: 220.43 ± 13.15 μg QE/gF.W; total tannins content: 16.47 ± 0.98 μg CE/gF.W), and antioxidant potentials are 2,2′-diphenyl-1-picrylhydrazyl: 2.23 ± 0.17 mg AAE/gF.W; 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid): 1.79 ± 0.09 mg AAE/gF.W; ferric reducing antioxidant power: 68.71 ± 11.11 μg AAE/gF.W (total antioxidant capacity: 1.22 ± 0.03 mg AAE/gF.W). The LC-ESI-QTOF-MS/MS analysis identified 87 compounds from blueberry (57), strawberry (40), raspberry (47), and blackberry wastes (27). Indicated by HPLC quantification, blueberry wastes had higher levels of phenolic acid (syringic acid and coumaric acid) and flavonoid (kaempferol and kaempfero l-3-glucoside). Our study reported that phenolics from berry wastes could be utilized in different food, feed, pharmaceutical, and nutraceutical industries.

Procyanidins: From Agro-Industrial Waste to Food as Bioactive Molecules

Procyanidins are an important group of bioactive molecules known for their benefits to human health. These compounds are promising in the treatment of chronic metabolic diseases such as cancer, diabetes, and cardiovascular disease, as they prevent cell damage related to oxidative stress. It is necessary to study effective extraction methods for the recovery of these components. In this review, advances in the recovery of procyanidins from agro-industrial wastes are presented, which are obtained through ultrasound-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, pressurized fluid extraction and subcritical water extraction. Current trends focus on the extraction of procyanidins from seeds, peels, pomaces, leaves and bark in agro-industrial wastes, which are extracted by ultrasound. Some techniques have been coupled with environmentally friendly techniques. There are few studies focused on the extraction and evaluation of biological activities of procyanidins. The identification and quantification of these compounds are the result of the study of the polyphenolic profile of plant sources. Antioxidant, antibiotic, and anti-inflammatory activity are presented as the biological properties of greatest interest. Agro-industrial wastes can be an economical and easily accessible source for the extraction of procyanidins.

Anthocyanin content and storage stability of spray/freeze drying microencapsulated anthocyanins from berries: a review

A comprehensive literature search for articles published on spray and freeze-dried anthocyanins from a large variety of berries was performed. Out of a total of two-hundred and eight collected values, anthocyanin content in encapsulates had a 120-fold variation depending on the raw material and type of encapsulating agents. Highest observed anthocyanin concentration amounted to about 3500 mg/100 g powder. In most cases increasing the amount of encapsulant agents led to a noticeable reduction in the concentration of anthocyanins, this being attributable to a predominance of the dilution effect. Retention of encapsulated anthocyanins after storage at 25 °C (in darkness) for periods between 90 and 180 days were in the range of 80–67%, as long as the water activity (aw) was 0.33 or less. Some predicted values of half-time (t1/2) from literature must be taken with precaution since in many cases they were derived from experimental measurements taken at storage times smaller than predicted half times. Anthocyanin degradation during storage occurred even below the glass transition temperature (Tg) of the amorphous matrices.

Extraction of Antioxidant Compounds from Blueberry Fruit Waste and Evaluation of Their In Vitro Biological Activity in Human Keratinocytes (HaCaT)

The purpose of this study was to investigate the biological properties of an extract obtained from the waste of blueberry fruit. The study covered the optimization of extraction of antioxidants from blueberry pomace and the determination of antioxidant properties of the extract using HaCaT as the model organism. Research showed that the yield of antioxidants extraction from blueberry waste was dependent on the applied extraction conditions. Based on the mathematical models, the optimal conditions of extraction process in which the maximum quantity of antioxidant compounds is achieved from the waste mass unit, i.e., the relation of the waste mass to the volume of ethanol equal to 1:17.36, and process time equal to 1000 s. The obtained extract was characterized by high antioxidant activity, which was shaped by high content of polyphenols, mainly anthocyanins. Moreover, the extract showed a high ability to protect HaCaT cells from the occurrence of oxidative stress induced by H2O2. Cells treated with the extract and H2O2 generated a lower amount of ROS than cells treated with H2O2 only. The obtained results will be base of further studies on applying the extract in production of diet supplements and functional foods with increased antioxidant activity. Moreover, the main research material is blueberry pomace which is a troublesome waste material for juice producers. Consequently, according to a sustainable development idea, the study results will provide an opportunity to increase interest in the problem of rational use of the waste material to a certain extent.

Valorization of Vegetable Fresh-Processing Residues as Functional Powdered Ingredients. A Review on the Potential Impact of Pretreatments and Drying Methods on Bioactive Compounds and Their Bioaccessibility

Food waste is a worldwide concern as it represents a constant threat to the environment and a serious operational problem for the food industry. The by-products of fruits and vegetables being a valuable source of bioactive compounds have the potential to be reused and reintroduced in the agri-food chain. This circular approach contributes to a sustainable production system. In this context, a collaborative project with the primary sector for the integral valorization of the waste generated in the fresh-processing vegetable lines of an agricultural cooperative is currently being developed, particularly focused on cabbage, carrot, celery, and leek. The objective of this project is to transform vegetable wastes into functional powdered ingredients and be able to use them in food formulations in order to improve the nutritional profile of foods, contributing to the development of sustainable healthy diets. Through an exhaustive bibliographic review, this research studies the influence of pretreatments, drying and in vitro digestion on the bioactive compounds of vegetable residues, with the aim of identifying the appropriate production parameters to achieve an adequate functional and physicochemical profile of the final powders.

The Effects of Bioactive Compounds from Blueberry and Blackcurrant Powder on Oat Bran Pastes: Enhancing In Vitro Antioxidant Activity and Reducing Reactive Oxygen Species in Lipopolysaccharide-Stimulated Raw264.7 Macrophages

In this study, blueberry and blackcurrant powder were chosen as the phenolic-rich enrichments for oat bran. A Rapid Visco Analyser was used to form blueberry and blackcurrant enriched oat pastes. An in vitro digestion process evaluated the changes of phenolic compounds and the in vitro antioxidant potential of extracts of pastes. The anthocyanidin profiles in the extracts were characterised by the pH differential method. The results showed that blueberry and blackcurrant powder significantly increased the content of phenolic compounds and the in vitro antioxidant capacity of pastes, while the total flavonoid content decreased after digestion compared to the undigested samples. Strong correlations between these bioactive compounds and antioxidant values were observed. Lipopolysaccharide-stimulated RAW264.7 macrophages were used to investigate the intracellular antioxidant activity of the extracts from the digested oat bran paste with 25% enrichment of blueberry or blackcurrant powder. The results indicated that the extracts of digested pastes prevented the macrophages from experiencing lipopolysaccharide (LPS)-stimulated intracellular reactive oxygen species accumulation, mainly by the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signalling pathway. These findings suggest that the bioactive ingredients from blueberry and blackcurrant powder enhanced the in vitro and intracellular antioxidant capacity of oat bran pastes, and these enriched pastes have the potential to be utilised in the development of the functional foods.

Microencapsulation of Pigments by Directly Spray-Drying of Anthocyanins Extracts from Blueberry Pomace: Chemical Characterization and Extraction Modeling

The aim of this study was to develop an environmentally friendly process to extract anthocyanins from blueberry pomace using water as a solvent and directly microencapsulate anthocyanins by spray drying. The anthocyanins in water and ethanol extracts were characterized by high-performance liquid chromatography and mass spectrometry. The malvidin-3-O-galactoside and malvidin-3-O-glucoside were identified as the main anthocyanins in the blueberry pomace. The anthocyanins profiles of water extracts were similar to that by ethanol extraction. The effects of extraction parameters including solid-to-liquid ratio and temperature on the extraction efficiency and anthocyanins concentration were studied. The blueberry anthocyanins degraded at temperatures higher than 60 °C and all anthocyanins showed similar degradation tendency. The result showed that the artificial neural network (ANN) modeling could be well used to portray the effects of these parameters. Finally, the water extracts were successfully spray dried to produce microencapsulation of blueberry anthocyanins with maltodextrin (MD) as wall materials.

Spray Drying of Blueberry Juice-Maltodextrin Mixtures: Evaluation of Processing Conditions on Content of Resveratrol

Resveratrol is an antioxidant abundant in red fruits, and one of the most powerful inhibiting reactive oxygen species (ROS) and oxidative stress (OS) produced by human metabolism. The effect of the spray drying processing conditions of blueberry juice (BJ) and maltodextrin (MX) mixtures was studied on content and retention of resveratrol. Quantitatively, analysis of variance (ANOVA) showed that concentration of MX was the main variable influencing content of resveratrol. Response surface plots (RSP) confirmed the application limits of maltodextrins based on their molecular weight, where low molecular weight MXs showed a better performance as carrying agents. After qualitatively comparing results for resveratrol against those reported for a larger antioxidant molecule (quercetin 3-D-galactoside), it was observed a higher influence of the number of active sites available for the chemical interactions, instead of stearic hindrance effects.

Development of Health Products from Natural Sources

BioActive Compounds (BACs) recovered from food or food by-product matrices are useful in maintaining well being, enhancing human health, and modulating immune function to prevent or to treat chronic diseases. They are also generally seen by final consumers as safe, non-toxic and environment-friendly. Despite the complex process of production, chemical characterization, and assessment of health effects, BACs must also be manufactured in stable and bioactive ingredients to be used in pharmaceutical, food and nutraceutical industry. Generally, vegetable derivatives occur as sticky raw materials with pervasive smell and displeasing flavor. Also, they show critical water solubility and dramatic stability behavior over time, involving practical difficulties for industrial use. Therefore, the development of novel functional health products from natural sources requires the design of a suitable formulation to delivery BACs at the site of action, preserve stability during processing and storage, slow down the degradation processes, mask lousy tasting or smell, and increase the bioavailability, while maintaining the BACs functionality. The present review focuses on human health benefits, BACs composition, and innovative technologies or formulation approaches of natural ingredients from some selected foods and by-products from industrial food transformations.