Physicochemical characterization, antioxidant capacity, total phenolic and proanthocyanidin content of flours prepared from pequi (Caryocar brasilense Camb.) fruit by-products

Buriti (Mauritia flexuosa) shell flour: Nutritional composition, chemical profile, and antioxidant potential as a strategy for valuing waste from native Brazilian fruits

The Cerrado is one of the most biodiverse biomes in the world, characterized by a wealth of native fruits with unique nutritional characteristics. In this sense, the social, economic, and environmental importance of fully utilizing food is widely recognized. Therefore, generally considered waste, fruit shells can be transformed into a coproduct with high added value. The objective of this work was to carry out a comprehensive assessment of the physicochemical properties, carbohydrate and fatty acid profile, phytochemical compounds, phenolic profile, and antioxidant potential of the recovered extracts of buriti (Mauritia flexuosa) shells in natura and dehydrated at 55 °C (flour). In addition, the functional properties were verified by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) from buriti shell flour. The results indicated high fiber content and energy value for the sample processed at 55 °C (58.95 g/100 g and 378.91 kcal/100 g, respectively) and low lipid and protein content (1.03 g/100 g and 1.39 g/100 g, respectively). Regardless of the sample analyzed, maltose was the majority sugar (37.33 - 281.01 g/100 g). The main fatty acids detected were oleic acid (61.33 - 62.08 %) followed by palmitic acid (33.91 - 34.40 %). The analysis of the mineral profile demonstrated that the samples did not differ significantly from each other, showing that the drying process did not interfere with the results obtained (p ≤ 0.05). The analysis of individual phenolics allowed the identification of six phenolic compounds in buriti shells. However, it is possible to observe that the drying method had a positive and significant influence on the phenolic profile (p ≤ 0.05), with chlorogenic acid (2.63 - 8.27 mg/100 g) and trigonelline (1.06 - 41.52 mg/100 g), the majority compounds. On the other hand, it is important to highlight that buriti shells have a high content of carotenoids, mainly β-carotene (27.18 - 62.94 µg/100 g) and α-carotene (18.23 - 60.28 µg/100 g), also being positively influenced by the drying process at 55 °C (p ≤ 0.05). The dried shells showed a high content of phytochemical compounds and high antioxidant activity based on the different methods tested. The results show that buriti shell flour can be fully utilized and has nutritional and chemical aspects that can be applied to develop new sustainable, nutritious, and functional food formulations.

Phenolic Compounds Characterization of Caryocar brasiliense Peel with Potential Antioxidant Activity

The pequi (Caryocar brasiliense) fruit peel, despite being frequently discarded, has a high content of bioactive compounds, and therefore has a high nutritional value. The present study aimed to explore the bioactivities in the pequi peel, particularly their potential health benefits at the level of antioxidant activity. The exploitation of this fruit could also present significant economic benefits and applications of pequi by-products would represent a reduction in waste, having a positive impact on the environment. Phenolic compounds present in the pequi exocarp and external mesocarp were identified by paper spray mass spectrometry (PS-MS) and quantified by HPLC. The total phenolic content (TPC) along with the amount of 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), and the amount of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) were also determined in peel extracts. Epicatechin was the most abundant phenolic compound found, followed by the caffeic, salicylic, and gallic acids. In addition, fingerprinting revealed compounds related to several beneficial health effects. In short, the results obtained were encouraging for potential applications of pequi peel in the field of functional foods.

Exploring differences in the physicochemical and nutritional properties of mango flours and starches

Mangoes contain several components that are beneficial for health, in addition to being potential sources of starch for the food industry. However, a substantial amount of fruit is lost in the field because it does not meet commercial standards, resulting in food losses and environmental damage. Herein, the physicochemical properties of mango flours and starches obtained from different parts of the fruit of two cultivars were evaluated. Mango peel flours have higher levels of proteins, fibers, minerals, carotenoids, ascorbic acid, and antioxidant activity than pulp flours, in addition to a higher yellowing index and water and oil-holding capacity, and can be used as a functional flour. The pulp flours, with the higher starch content, showed characteristics that make them valuable as a potential ingredient in soft baking and gluten-free products. Mango starches have circular and oval shapes, with a bimodal distribution. All starches showed an A-type crystallinity pattern. Pulp starches showed a higher peak viscosity and breakdown, with a lower setback, and can be used as a thickening or gelling agent. The higher thermal stability of kernel starch suggests its application in sauces, baking, dairy products, and canned foods.

Physicochemical and Nutritional Properties of Vegetable Oils from Brazil Diversity and Their Applications in the Food Industry

In this study, the oils of açaí, passion fruit, pequi, and guava were submitted to physicochemical analysis to investigate their potential application in the food industry. Gas chromatography associated with mass spectroscopy showed that oleic and linoleic acids are mainly responsible for the nutritional quality of açaí, passion fruit, pequi, and guava oils, which exhibited 46.71%, 38.11%, 43.78%, and 35.69% of the former fatty acid, and 18.93%, 47.64%, 20.90%, and 44.72% of the latter, respectively. The atherogenicity index of the oils varied from 0.11 to 0.65, while the thrombogenicity index was 0.93 for açaí, 0.35 for guava, and 0.3 for passion fruit oils, but 1.39 for pequi oil, suggesting that the use of the first three oils may lead to a low incidence of coronary heart disease. Thermogravimetry showed that all tested oils were thermally stable above 180 °C; therefore, they can be considered resistant to cooking and frying temperatures. In general, the results of this study highlight possible applications of these oils in the food industry, either in natura or in typical food production processes.

Sources of Carotenoids in Amazonian Fruits

Epidemiological studies have shown that a diet rich in bioactive components significantly reduces cardiovascular disease incidence and mortality. In this sense, there is a need for meta-analytical research that confirms this phenomenon and increases specific knowledge about certain bioactive compounds such as carotenoids. Thus, this systematic review and meta-analysis aim to disseminate knowledge about the sources of carotenoids in fruit consumed in the north of Brazil which are outside the Brazilian trade balance. A systematic review and a meta-analysis following the PRISMA guidelines were conducted based on a random effects synthesis of multivariable-adjusted relative risks (RRs). Searches of seven sources were carried out, including PubMed, Science Direct from Elsevier, Web of Science, Scielo, Eric Research and Google Scholar databases. The systematic review was guided by a systematic review protocol based on the POT strategy (population, outcome and type of study) adapted for use in this research. Mendeley was a resource used to organize and manage references and exclude duplicates of studies selected for review. In this review, we present the potential bioactive compounds concentrated in little-known fruit species from the Amazon and their benefits. Consuming fruits that are rich in notable constituents such as carotenoids is important for the prevention of chronic non-communicable diseases through anti-inflammatory and anticoagulant properties, as well as antivirals, immunomodulators and antioxidants agents that directly affect the immune response.

Exploring the association between a standardized extract of pequi peels (Caryocar brasiliense Cambess) and blue light as a photodynamic therapy for treating superficial wounds

Natural products derived from plants can be used as photosensitizers for antimicrobial photodynamic therapy (aPDT) combining key therapeutic strategies for tissue repair while controlling microorganisms' growth. We investigated a standardized extract of pequi peels (Caryocar brasiliense Cambess) as a brownish natural photosensitizer for aPDT using blue light. Three concentrations of the pequi extract (PE; 10, 30, or 90 μg/mL) were tested solely or associated with blue laser (445 nm, 100 mW, 138 J/cm2, 6 J, 60 s). In vitro, we quantified reactive oxygen species (ROS), assessed skin keratinocytes (HaCat) viability and migration, and aPDT antimicrobial activity on Streptococcus or Staphylococcus strains. In vivo, we assessed wound closure for the most active concentration disclosed by the in vitro assay (30 μg/mL). Upon aPDT treatments, ROS were significantly increased in cell monolayers regardless of PE concentration. PE at low doses stimulates epithelial cells. Although PE stimulated cellular migration, aPDT was moderately cytotoxic to skin keratinocytes, particularly at the highest concentration. The antimicrobial activity was observed for PE at the lowest concentration (10 μg/mL) and mostly at PE 10 μg/mL and 30 μg/mL when used as aPDT photosensitizers. aPDT with PE 30 μg/mL presents antimicrobial activity without compromising the initial phases of skin repair.

Melon peel flour: utilization as a functional ingredient in bakery products

Food by-products are a major concern with a direct impact on the economy, society, and environment. The valorisation of these by-products could be an advantageous approach to face the increase in food waste since it can compromise environmental health and food sustainability. On the other hand, this valorisation would allow the development of new food products with health benefits for the population. Cucumis melo L. is a highly consumed fruit all over the world since it has excellent sensory and nutritional qualities, being also a good source of bioactive compounds. However, its peel and seeds are usually discarded. The aim of this study was to evaluate the potential of melon peel flour as a functional ingredient for innovative food products. For that, two different formulations containing melon peel flour were developed (a biscuit and a muffin) by replacing a conventional flour (wheat flour) in different percentages (50% and 100%, respectively). The nutritional composition, total phenolic content, and antioxidant potential of the developed products were studied, showing a high content of fibre, high levels of phenolic compounds and good sensory acceptability. These results show that it is possible to enrich different foods with melon peel flour in order to improve their nutritional properties, contributing to improving public health, simultaneously valorising a usually rejected by-product, reducing food waste and the environmental impact.

Preserving nutrient content in red cabbage juice powder via foam-mat hybrid microwave drying: Application in fortified functional pancakes

Red cabbage, a highly nutritious cool-season cruciferous vegetable, is rich in anthocyanins; however, the instability of anthocyanins during processing and storage poses challenges. This study aimed to optimize the foam-mat drying process of red cabbage juice (RCJ) with a high anthocyanin content using a hybrid microwave hot air-drying system (MW-HAD) as a dehydration method compared to conventional techniques (HAD) using response surface methodology (RSM). Additionally, the produced red cabbage juice powder (RCJP) was used to enrich the pancake formulation. The developed model exhibited a high degree of reliability with optimal conditions and was determined for microwave power, temperature, foaming agent carboxymethylcellulose (CMC), and egg white protein (EWP) as 360 W, 60°C, 0.3%, and 1.2%, respectively. Moisture content (%) was decreased from 93.47 to 8.62 at optimum process conditions. In comparison to the control (60°C), foam mat drying with the MW-HAD hybrid system reduced the drying time (DT) by more than 90.9% due to the higher drying rate, while many physicochemical properties, especially total anthocyanin content (TAC), were better preserved. Utilization of RCJP in the production of anthocyanin-rich functional pancakes resulted in enhanced nutritional qualities compared to control pancakes with increased protein (35.07%), total phenolic (75.8%), dietary fiber (82.9%), and anthocyanin content (100%). In conclusion, MW-HAD demonstrates significant potential as a promising drying method to reduce the DT and preserve the physicochemical properties of RCJP. Furthermore, the application of the optimized RCJP in anthocyanin-rich functional pancakes highlights improved nutritional qualities, making a substantial contribution to the advancement of functional foods.

Prebiotic Activity of Pequi (Caryocar brasiliense Camb.) Shell on Lactobacillus and Bifidobacterium Strains: A Medicinal Food Ingredient

Pequi is a native and popular fruit in Cerrado biome. The internal yellow-orange mesocarp is the edible fraction of the fruit, but its shell (peel and external mesocarp), which comprises 80% of the fruit, is not used by the agro-industry during fruit processing. There is a growing interest in the reduction of food loss and waste because of environmental, economic, and social impacts. So this study evaluated the chemical composition, antioxidant capacity, and in vitro prebiotic activity of pequi shell flour. Pequi shell flour was obtained from the lyophilization and milling of pequi shell. The content of dietary fibers, oligosaccharides, sugars, organic acids, total phenolics and tannins, polyphenol profile, and antioxidant capacity was determined in pequi shell flour. In addition, its prebiotic activity was evaluated on growth and metabolism of probiotics Lactobacillus and Bifidobacterium strains. Pequi shell flour has a high content of dietary fibers (47.92 g/100 g), soluble fibers (18.65 g/100 g), raffinose (2.39 g/100 g), and phenolic compounds (14,062.40 mg gallic acid equivalents/100 g). For the first time, the polyphenols epigallocatechin gallate, epicatechin, and procyanidin B2 were identified in this by-product. Pequi shell flour promoted greater growth of Lacticaseibacillus casei L-26 (at 24-48 h) and Bifidobacterium animalis subsp. lactis BB-12, as well as higher prebiotic activity scores than fructooligosaccharides (standard prebiotic). Pequi shell flour is rich in prebiotic compounds and has a high antioxidant and prebiotic potential. The promising results encourage its use as an ingredient with antioxidant and potential prebiotic properties to elaborate new functional foods and nutraceuticals.

Cytotoxic and Phytotoxic Activities of Native Brazilian Forest Gabiroba (Campomanesia xanthocarpa Berg.), Fruits, and Flour against Shrimp (Artemia salina L.) and Lettuce (Lactuca sativa L.)

Gabiroba, a native fruit in Brazil's Atlantic Forest region, has significant nutritional and therapeutic properties. However, due to its seasonality, consumption by the population is limited. Thus, the development of gabiroba byproducts would add significant value to the food and therapeutic industries. Therefore, it is essential to study and support the lack of toxicity of gabiroba fruit extracts. In the present study, physicochemical analyses of fresh fruits (GF) and dehydrated whole gabiroba flour (WGF) and preliminary toxicity analyses of WGF were performed. The toxicity results showed a microcrustacean LC50 of >1000 mg/mL when exposed to WGF extracts at various concentrations (10-1000 μg/mL; p = 0.062) using the Artemia salina method, with no evidence observed of proliferative activity or toxic metabolic compounds in the WGF extract. The phytotoxicity of WGF using Lactuca sativa L. allowed germination and root growth at various concentrations of WGF extract, with the lowest (100 μg/mL) and highest (1000 μg/mL) concentrations exhibiting 98.3% and 100% seed germination, respectively. In conclusion, these results indicate that the WGF preparation preserved the nutritional and antioxidant potential of gabiroba fruits and that WGF is safe for use as a raw material in the food industry and for therapeutic purposes.

Fermentation of araticum, baru, and pequi by-products by probiotic strains: effects on microorganisms, short-chain fatty acids, and bioactive compounds

Fruit by-products, due to their unique chemical composition containing dietary fibers and bioactive compounds, may favor the growth of probiotic strains. This study evaluated the fermentation of araticum, baru, and pequi by-products using Lactobacillus acidophilus (La-5, LA3, and NCFM) and Bifidobacterium animalis subsp. lactis (Bb-12) probiotic strains. We assessed probiotic viability, short-chain fatty acid levels, and bioactive compound levels after 48 h of fermentation. Araticum and pequi by-products led to counts higher than 6 log CFU/mL after 48-h fermentation for all Lactobacillus strains, but only the araticum by-product supported the growth of the Bb-12 strain. Fermentation of araticum by-product resulted in greater amounts of acetate (39.97 mM for LA3 and 39.08 mM for NCFM) and propionate (0.20 mM for NCFM), while baru by-product showed greater amounts of butyrate (0.20 mM for La-5 and Bb-12). Fermentation of araticum and baru by-products resulted in an increase in bioactive compounds, with the latter showing total phenolic compounds and antioxidant activity from 1.4 to 1.7 and from 1.3 to 3.1 times higher, respectively, than the negative control treatment. Araticum by-product exhibited a higher potential for prebiotic effects, and fermentation by the tested probiotic strains is essential to increase bioactive compound levels.

Physical, chemical and sensory implications of pequi (Caryocar brasiliense Camb.) sweet bread made with flour, pulp and fruit by-product

This study aimed to develop and evaluate bread with the use of pulp and flours of pequi, in partial replacement of water and wheat flour, to develop a bakery product with good technological, nutritional and sensorial qualities. The pequi husk and pulp flours were obtained by means of a thermal pre-treatment, oven drying and standardization of the dry material. Whereas, the bread formulation was defined through the baker's formulation. Besides, the dehydration process caused significant changes (p<0.05) in the L* value and chromaticity (C*), mainly of the flours (husk and pequi pulp), such changes are due to non-enzymatic oxidative processes and pigment degradation, especially carotenoids. The effect of the substitution of ingredients (wheat flour and water) by husk and pulp flours and pequi pulp contributed to the increase in lipid, crude fiber, nitrogen-free extract and energy value content. However, the substitution promoted changes in the attributes of color and textural properties, such as increased hardness, chewiness and cohesiveness. Nevertheless, all formulations showed good sensory acceptance and thus, pequi sweet breads can be implemented in school meals for contributing and meeting the nutritional recommendations established by the School Feeding Brazilian Program (PNAE).

Development and Characterization of Yellow Passion Fruit Peel Flour (Passiflora edulis f. flavicarpa)

In this study, the peels of the yellow passion fruit (Passiflora edulis f. flavicarpa) were used to develop a flour that was evaluated in terms of its physicochemical, microscopic, colorimetric, and granulometric characteristics, its total phenolic compound and carotenoid contents, and its antioxidant capacity. Fourier Transform Infrared (FTIR) spectroscopy measurements were employed to investigate the constituent functional groups, compounds' chemical profiles were assessed by Paper Spray Mass Spectrometry (PS-MS), and the compound's chemical profiles were evaluated by Ultra-Performance Liquid Chromatography (UPLC). This flour presented a light color, heterogeneous granulometry, high carbohydrate, carotenoid, and total phenolic compound contents with high antioxidant capacity. Scanning Electron Microscopy (SEM) showed a particulate flour, which is supposed to contribute to its compactness. FTIR demonstrated the presence of functional groups corresponding to cellulose, hemicellulose, and lignin, constituents of insoluble dietary fiber. The PS-MS analysis suggested the presence of 22 substances, covering diverse component classes such as organic, fatty, and phenolic acids, flavonoids, sugars, quinones, phenylpropanoid glycerides terpenes, and amino acids. This research demonstrated the potential of using Passion Fruit Peel Flour (PFPF) as an ingredient for food products. The advantages of using PFPF comprise the reduction of agro-industrial waste, contribution to the development of a sustainable food system, and increment of food products' functional profile. Moreover, its high content of several bioactive compounds can benefit consumers' health.

Potential Challenges of the Extraction of Carotenoids and Fatty Acids from Pequi (Caryocar brasiliense) Oil

Pequi is a natural source of bioactive compounds with wide versatility for fresh or processed fruit consumption, but it is still little explored economically. Functional foods are the subject of diverse scientific research since, in addition to being nourishing, they contain bioactive compounds capable of promoting several benefits to the human body. Pequi is a fruit species native to the Brazilian Cerrado, which is rich in oil and has components with a high nutritional value, such as unsaturated fatty acids (omega-3, omega-6, EPA, and DHA), antioxidants (carotenoids and phenolic compounds), and vitamins. Therefore, the present narrative review aims to compile and critically evaluate the methods used to extract oil from the pulp and almonds of pequi and describes the carotenoid separation from the oil because carotenoids are natural pigments of great interest in the pharmaceutical and food industries. It is emphasized that the main challenges linked to bioactive compound extraction are their susceptibility to degradation in the processing and storage stages of pequi and its derived products.

Changes in the Fruit Quality, Phenolic Compounds, and Antioxidant Potential of Red-Fleshed Kiwifruit during Postharvest Ripening

Kiwifruit is very popular for its unique flavor and nutritional value, and for its potential health benefits, which are closely related to its richness in a variety of natural antioxidant substances, in which polyphenolics play a non-negligible role. This study investigated changes in the fruit quality, phenolic compounds, and antioxidant potential of Chinese red-fleshed kiwifruit “Hongshi No. 2” during postharvest ripening at room temperature (20 ± 1 °C). Results showed that the weight loss rate slowly increased, the firmness rapidly decreased, and the soluble solid concentration gradually increased during the postharvest ripening of red-flesh kiwifruit. In addition, the total phenolic (TPC), total flavonoid (TFC), and total proanthocyanidin (TPAC) contents gradually increased during postharvest ripening. The most abundant phenolic compounds in kiwifruit throughout postharvest ripening were catechin (CC), proanthocyanidin B1 (PB1), and proanthocyanidin B2 (PB2). Furthermore, the methanolic extracts of red-flesh kiwifruit exhibited remarkable antioxidant activities throughout postharvest ripening stages. Indeed, some phenolic compounds showed good correlations with antioxidant activities; for instance, chlorogenic acid (CHL) showed a significantly positive correlation with ferric reducing antioxidant power (FRAP), and isoquercitrin (IS) showed a significantly negative correlation with DPPH free radical scavenging ability. The findings from this study are beneficial to better understanding the quality profile of red-flesh kiwifruit “Hongshi No. 2” during postharvest ripening.

Nutritional composition and minerals bioaccessibility of commercial fruit flours

Commercial fruit flours were evaluated concerning: (i) the nutritional composition (proximate composition, total phenolic content, and minerals content), (ii) their contribution to estimated mineral daily intake, (iii) the bioaccessibility of essential minerals using the in vitro INFOGEST digestion method and (iv) the influence of their chemical composition on minerals bioaccessibility. The 20 samples analysed presented high variability concerning the content of dietary fibre (7.5 to 69.7 g/100 g), carbohydrates (4.1 to 74.9 g/100 g), protein (2.9 to 12.9 g/100 g), ash (1.0 to 7.0 g/100 g), lipids (1.0 to 8.1 g/100 g) and total phenolic content (2.9 to 41.0 mg GAE/g. The mineral content of fruit flours provides a great contribution to the daily mineral requirements (especially Mg, Fe, Mn and Cu) with a daily intake of 30 g and very low contribution to the daily requirements of Na (0–3%). Low bioaccessibility was observed for Ca (18.0%) and Fe (28.9%), while Mg was the most bioaccessible mineral (81.5%). Though, the bioaccessible fraction of Mg showed negative correlation with total dietary fibre content (r = − 0.77) and lipids (r = − 0.46).

Antioxidant effect of blueberry flour on the digestibility and storage of Bologna-type mortadella

The aim of the study was to add blueberry flour (BF) to Bologna-type mortadella as a natural antioxidant and to evaluate its activity during in vitro digestion and refrigerated storage. Five treatments of mortadella were prepared: without antioxidant, with sodium erythorbate and with the addition of three levels of BF: 0.05 %, 0.075 % and 0.1 %. Twenty-three phenolic compounds were quantified in blueberry fruits and twenty-eight in BF, with prevalence of chlorogenic acid. The presence of BF did not affect the proximal composition of the mortadella, but it had a small effect on pH, hardness (texture profile) and instrumental color, as well as reduced lipid oxidation during refrigerated storage (2-8 °C) for 90 days. During in vitro digestion, the addition of BF increased the content of total phenolic compounds and the antioxidant activity of mortadella (p < 0.05), among all simulated stages. At a concentration of 0.05 %, BF can be used as a synthetic antioxidant substitute in Bologna-type mortadella, enhancing the use of blueberry fruits in the form of flour and enriching the product with natural antioxidants.

Microencapsulation by Spray Drying and Antioxidant Activity of Phenolic Compounds from Tucuma Coproduct (Astrocaryum vulgare Mart.) Almonds

The industrial processing of fruits in the Amazon region, such as tucuma, generates a large amount of coproducts with great nutritional potential. In this work, phenolic compounds from tucuma coproduct almonds were extracted and microencapsulated by spray drying using maltodextrin as the encapsulating agent and verified its antioxidant activity. Phenolic compounds were determined by UV spectroscopy and identified by Ultraefficiency Liquid Chromatography. Antioxidant activity was measured by ABTS and DPPH assay. Thermogravimetric techniques, infrared spectroscopy, scanning electron microscopy, moisture content and water activity were applied to characterize the microparticle. The crude extract and microparticle had total polyphenols of 135.1 mg/g ± 0.078 and 130.5 mg/g ± 0.024, respectively. Caffeic and gallic acids were identified. The crude extract and the microparticle showed good antioxidant activity by ABTS and DPPH assay, justified by the presence of the phenolic compounds found. The microparticle showed spherical and heterogeneous structures and good encapsulation efficiency from the spray drying process using maltodextrin. The results show that the extract of the tucuma almond coproduct can be used as a phenolic compound-rich source and microencapsulated with possible application for functional food production.

Potential Uses of Spent Coffee Grounds in the Food Industry

Current estimates place the amount of spent coffee grounds annually generated worldwide in the 6 million ton figure, with the sources of spent coffee grounds being classified as domestic (i.e., household), commercial (i.e., coffee houses, cafeterias and restaurants), and industrial (i.e., soluble and instant coffee industries). The majority of the produced spent coffee grounds are currently being inappropriately destined for landfills or to a form of energy recovery (e.g., incineration) as a refuse-derived fuel. The disposal of spent coffee in landfills allows for its anaerobic degradation with consequent generation and emission of aggressive greenhouse gases such as methane and CO₂, and energy recovery processes must be considered an end-of-life stage in the lifecycle of spent coffee grounds, as a way of delaying CO₂ emissions and of avoiding emissions of toxic organic volatile compounds generated during combustion of this type of waste. Aside from these environmental issues, an aspect that should be considered is the inappropriate disposal of a product (SCG) that presents unique thermo-mechanical properties and textural characteristics and that is rich in a diversity of classes of compounds, such as polysaccharides, proteins, phenolics, lipids and alkaloids, which could be recovered and used in a diversity of applications, including food-related ones. Therefore, researchers worldwide are invested in studying a variety of possible applications for spent coffee grounds and products thereof, including (but not limited to) biofuels, catalysts, cosmetics, composite materials, feed and food ingredients. Hence, the aim of this essay was to present a comprehensive review of the recent literature on the proposals for utilization of spent coffee grounds in food-related applications, with focus on chemical composition of spent coffee, recovery of bioactive compounds, use as food ingredients and as components in the manufacture of composite materials that can be used in food applications, such as packaging.

Physicochemical and bioactive properties of avocado (Persea americana Mill. cv. Lorena)

Chemical compounds are of great importance in the food, cosmetic and pharmaceutical industries. Nutritional components, the presence of secondary metabolites with antioxidant and antimicrobial activity, and physicochemical properties of pulp, seed and peel of Lorena avocado cultivars were studied. Antioxidant activity was evaluated by ABTS, DPPH and lipid peroxidation in pulp, seed and peel. 26 extracts was evaluated. The results confirmed that the fruit parts stabilize free radicals and inhibit lipid oxidation processes, with the highest values in seed and peel, due to their content of flavonoids, o-diphenols and phenols. The results of phytochemical screening, antioxidant capacity and antimicrobial activity, showed significant bioprospective advantage for the presence of flavonoids, condensed tannins and total phenols in the seed, peel and pulp of Lorena avocado cultivars. Avocado fruits are rich in bioactive compounds that can be used in functional food applications.

Bioacessibilidade in vitro de carotenoides e compostos fenólicos e capacidade antioxidante de farinhas do fruto pequi (Caryocar brasiliense Camb.)

Resumo Este trabalho objetivou avaliar a bioacessibilidade in vitro de α-caroteno, β-caroteno, licopeno e de compostos fenólicos, e a capacidade antioxidante em farinhas de amêndoa, polpa e casca do fruto pequi. Além disso, inter-relacionar estes resultados com a atividade de água, acidez e parâmetros de cor, por meio da análise de componentes principais. Os frutos foram coletados no estado de Mato Grosso, sendo higienizados, descascados, despolpados e retiradas as amêndoas. A quantificação das concentrações totais e bioacessíveis dos carotenoides e compostos fenólicos e a capacidade antioxidante foram feitas por espectrofotometria UV-Visível. Os ensaios de bioacessibilidade in vitro foram feitos por meio de três etapas: digestão salivar, gástrica e intestinal. As maiores concentrações de α-caroteno (63,81 µg/g), β-caroteno (59,83 µg/g) e licopeno (40,66 µg/g) foram obtidas para farinha da polpa do pequi. Porém, as maiores porcentagens de bioacessibilidade de α-caroteno (59,69%), β-caroteno (96,14%) e licopeno (44,13%) foram encontradas na farinha da amêndoa. Os teores de compostos fenólicos totais foram: 210,50, 402,21 e 9475,69 mg GAE/100g, para as farinhas de amêndoa, polpa e casca, respectivamente, sendo a maior porcentagem de bioacessibilidade (86,68%) encontrada na farinha da polpa. A farinha da casca do pequi apresentou maior capacidade antioxidante (EC50) 45,71 g/g de DPPH. Os maiores resultados de L* (42,19), a* (4,17), b* (8,39) e acidez titulável (17,83 mL NaOH/100 g) foram verificados na farinha da polpa e o menor pH (3,34), na farinha da casca. A análise de componentes principais indicou que o pH e a acidez titulável podem influenciar na bioacessibilidade de compostos fenólicos e carotenoides, e na capacidade antioxidante. Os resultados sugerem que as farinhas do pequi apresentam compostos bioativos bioacessíveis e boa capacidade antioxidante, e podem ser uma alternativa tecnológica no enriquecimento de produtos alimentícios.

Nutritional potential of Vasconcellea quercifolia A. St.-Hil. green fruit flour

Abstract Non-conventional food plants have a variety of bioactive compounds with nutritional value. Vasconcellea quercifolia A. St.-Hil., belonging to the Caricaceae family, is a dietary alternative with excellent nutritional composition. This study aimed at characterizing the nutritional composition of mountain papaya (V. quercifolia) green fruit flour, in order to incorporate it in a functional food. For that purpose, the flour was characterized regarding its macro and micronutrients, anti-nutritional factors, pH, water activity, and color. This flour showed contents of carbohydrate of 22.31%; protein of 9.65%; dietary fiber of 32.80%; lipids of 14.95%, 63.56% of which are unsaturated fatty acids, especially oleic acid; and ash of 9.10%, with higher concentrations for potassium, calcium and magnesium. Therefore, V. quercifolia flour had good nutritional characteristics and might be used as supplementary food.

Pantanal’s fish native meatballs has the nutritional values increased with the use of pequi in its recipe

The study aimed to evaluate whether the addition of pequi increases the nutritional value of meatballs made with piranha and pacu fillets. Piranhas were obtained from the colony of fishermen; pacu with the fish farmer and the pequis were collected in nature. Fish were filleted and triturated, and the resulting masses were used to prepare 4 types of meatballs: piranha fillet with 2.0% pequi pulp, piranha fillet without pequi pulp, pacu fillet with with 2.0% pequi pulp, and pacu fillet without pequi pulp. After preparation, acceptance, purchase intention and frequency of consumption were evaluated with untrained tasters. Chemical composition parameters evaluated were crude protein, lipids, ash, moisture, carotenoids and antioxidant activity. Results of acceptability for all formulations were similar. The chemical composition of piranha meatballs presented differences (p < 0.05) for lipids and carotenoids. Pacu meatballs showed no difference (p > 0.05) for moisture, carotenoids, and antioxidant activity. The addition of pequi did not alter the organoleptic characteristics, however increased the nutritional values, therefore, it can add value to the product to be marketed and be more nutritionally attractive to the consumer.

Chemical Characterization of Coffee Husks, a By-Product of Coffea arabica Production

Coffee husks are a major by-product of coffee production and are currently being underutilized. The aim of this work was to chemically characterize coffee husks to allow for an adequate evaluation of their potential for valorization. Blanched and non-blanched coffee husks were characterized for extractable and non-extractable phenolics, caffeine, trigonelline content, and for their polysaccharide and proximal composition. The total, soluble and insoluble fiber contents were determined, together with the husks’ technological properties. Antioxidant activity and bioaccessibility of phenolic compounds of coffee husks were evaluated. Two types of husk were studied: one comprised mostly of outer skin and pulp (CH1); and other comprised mostly of parchment (CH2). Blanching had positive effects on non-extractable phenolics, chlorogenic acid and on the bioaccessibility of phenolics, promoting small reductions in extractable phenolics, protocathecuic acid, caffeine and trigonelline contents. Blanched CH1 presented more appropriate properties than CH2 for potential applications in food. It also presented better antioxidant, hydration, and oil holding properties than those of other agri-food by-products. Tentatively identified polysaccharides included galactomannans, arabinogalactans type II, pectin and cellulose.

Chemical Characterization and Bioaccessibility Assessment of Bioactive Compounds from Umbu (Spondias tuberosa A.) Fruit Peel and Pulp Flours

Umbu, a common fruit from the northeastern region of Brazil, contains many bioactive compounds not yet exploited. Thus, this study evaluated the potential of pulps and peels of mature and semi-mature umbu as a source of bioactive compounds. Trigonelline contents ranged from 1.75 to 6.14 mg/100 g, values higher than those of many vegetables described in the literature, such as corn and barley. The contents of extractable and non-extractable phenolic compounds were also higher than those of other vegetables. Bioaccessibility of total extractable phenolics, flavonoids, and tannins was determined (15.67–37.73%, 31.87–39.10% and 18.81–114.27%, respectively). The constituent polysaccharides of the pulp and peel were tentatively chemically characterized as arabinoxylans, arabinogalactans, rhamnoarabinogalactans, xyloglucans, and pectin of the rhamnogalacturonan type. The technological potential of peel flours was evaluated. The maturation advancement showed no significant changes in the technological properties of the flours, except for color and water solubility index. Results indicated excellent prospects for future research on umbu pulps and peels as potential sources of natural bioactive compounds.

Bound Polyphenols from Insoluble Dietary Fiber of Defatted Rice Bran by Solid-State Fermentation with Trichoderma viride: Profile, Activity, and Release Mechanism

This study is aimed at exploring the release of bound polyphenols (BP) from insoluble dietary fiber (IDF) and its mechanism by solid-state fermentation (SSF) via Trichoderma viride. The results indicated that BP released by SSF (5.55 mg GAE/g DW) was significantly higher than by alkaline hydrolysis. In addition, 39 polyphenols and catabolites were detected, and the related biotransformation pathways were speculated. Quantitative analysis showed that SSF released more ferulic acid, p-coumaric acid, and organic acids, which led to advances in antioxidant, α-amylase, and α-glucosidase inhibitory activities. Furthermore, structural characteristics (scanning electron microscopy, X-ray diffraction, thermos gravimetric analysis, and Fourier transform infrared spectroscopy) and dynamic changes of carbohydrate-hydrolyzing enzymes indicated that the destruction of hemicellulose and the secretion of xylanase were vital for releasing BP. Overall, this study demonstrated that SSF was beneficial to release BP from IDF, which could provide insight into utilizing agricultural byproducts in a more natural and economical way.

Unripe Papaya By-Product: From Food Wastes to Functional Ingredients in Pancakes

Papaya is one of the most economic and valuable fruits in tropical countries. However, the fruit processing industries generate a high volume of unripe papaya waste and by-products. To reduce this waste, unripe papaya powder (UPP) was manufactured and incorporated into pancake formulation. The results showed that a particle size of UPP was 140.8 ± 2.1 µm, which contained polyphenolic compounds, dietary fiber and demonstrated ferric reducing antioxidant power (FRAP). Compared with wheat flour, UPP had higher values of water absorption index, water solubility index and swelling index and lower level of amylose. In the cholesterol-reducing effect, UPP decreased the formation of cholesterol micellization and bound bile acids. Interestingly, incorporation of 5-20% UPP into pancakes could decrease the glucose release with a concomitant increase in the percentage of undigestible starch. The hardness and chewiness of pancake was increased with a higher amount of UPP (10-20%). The results suggest that UPP from fruit processing waste can be regarded as a promising functional ingredient to incorporate with pancakes.

Physicochemical Characterization, Stability and Cytotoxicity of a Blue Dye Obtained from Genipap Fruit (Genipa americana L.)

Research background

The current commercial scenario indicates an increase in the demand for natural dyes. Compared to synthetic dyes, natural ones have the advantage of being sustainable, making them of great interest for the food and cosmetic industries. The development of new natural dyes is necessary, as well as the carrying out of complementary research regarding the existing ones.

Experimental approach

The present study aims to characterize the physicochemical and biological characteristics of the dye obtained from dehydrated endocarp of the genipap (Genipa americana) fruit, as well as perform the relevant stability and cytotoxicity tests. The chemical characterization was performed by HPLC-MS/MS analyses. The stability studies were carried out by spectrophotometry and cytotoxicity assays using cell culture and fluorometric methods.

Results and conclusions

After dehydration and milling of the fruit endocarp, water was added to the obtained powder (in the ratio 4:1) to extract the dye. Five compounds were elucidated using HPLC-MS/MS and confirmed the presence of the geniposide as its main compound. With the X-ray diffraction and electron microscopy analysis, we characterised the obtained powder as being amorphous and of porous structure with a variable size. The thermogravimetric analysis indicated a maximum loss of 61% mass after exposure to a temperature range from 240 to 760 °C. The obtained blue dye was stable in the absence of light, at room temperature and had neutral pH. In the cytotoxicity assay, (95.0±1.3) % of viable human fibroblasts were observed after exposure to this dye. The genipap fruit can be a viable alternative to produce a natural blue dye, since it is easy to obtain and has very low toxicity in food, pharmaceutical or cosmetic products.

Novelty and scientific contribution

This study demonstrates for the first time the physicochemical and biological properties of a natural blue dye from G. americana fruit.

Profile of bioactive compounds in pequi (Caryocar brasilense Camb.) peel flours

The bioactive compounds of pequi peel flours were characterized. Flavonoid contents ranged from 19.67 to 87.61 mg/100 g, high in comparison to many vegetables described in the literature. Gallic acid (11.52-418.67 mg/100 g), gallate ethyl (2026.75 - 5205.90 mg/100 g), ellagic acid (509.47 - 1630.66 mg/100 g), lutein (0.17-1.36 mg/100 g), β-carotene (0.82 - 1.49 mg/100 g), and β-cryptoxanthin (0.07 - 0.11 mg/100 g) were identified by HPLC, contributing to a greater valorization of the pequi peel flours. Phytochemical tests indicated the presence of hydrolyzable tannins and saponins. The detection of these compounds makes the product commercially attractive, in addition to generating value for an agro-industrial residue. The results obtained in this study confirm the multifunctional potential of pequi peel flour as a functional ingredient.

Bioguided chemical characterization of pequi (Caryocar brasiliense) fruit peels towards an anti-diabetic activity

Pequi fruit peels are an underexploited source of polyphenols. The anti-diabetic potential of an extract and fractions from the peels were evaluated in a panel of assays. The extract and fractions thereof inhibited the release of cytokines involved in insulin resistance - TNF, IL-1β, and CCL2 - by lipopolysaccharide-stimulated THP-1 cells. The ethyl acetate fraction inhibited in vitro α-glucosidase (pIC₅₀ = 4.8 ± 0.1), an enzyme involved in the metabolization of starch and disaccharides to glucose, whereas a fraction enriched in tannins (16C) induced a more potent α-glucosidase inhibition (pIC₅₀ = 5.3 ± 0.1). In the starch tolerance test in mice, fraction 16C reduced blood glucose level (181 ± 10 mg/dL) in comparison to the vehicle-treated group (238 ± 11 mg/dL). UPLC-DAD-ESI-MS/MS analyses disclosed phenolic acids and tannins as constituents, including corilagin and geraniin. These results highlight the potential of pequi fruit peels for developing functional foods to manage type-2 diabetes.

Safety and bioactive potential of nanoparticles containing Cantaloupe melon (Cucumis melo L.) carotenoids in an experimental model of chronic inflammation

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Carotenoids present anti-inflammatory effects in healthy and overweight adults.

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Nanotechnology can enhance carotenoid's bioactive potential.

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Nanoparticles loaded with carotenoids from Cantaloupe melon were used in obese rats.

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Animals receiving the nanoparticles showed no signs of toxicity.

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Animals treated with nanoparticles had organs better aspect compared to untreated.

The safety and bioactive potential of crude carotenoid extract from Cantaloupe melon nanoencapsulated in porcine gelatin (EPG) were evaluated in a chronic inflammatory experimental model. Animals were fed a high glycemic index and high glycemic load (HGLI) diet for 17 weeks and treated for ten days with 1) HGLI diet, 2) standard diet, 3) HGLI diet + crude carotenoid extract (CE) (12.5 mg/kg), and 4) HGLI diet + EPG (50 mg/kg). General toxicity signals were investigated, considering body weight, food intake, hematological, biochemical parameters, relative weight, morphology, and histopathology of organs. The biochemical parameters indicated the low toxicity of EPG. Acute hepatitis was observed in animals' livers, but CE and EPG groups presented improved tissue appearance. Chronic enteritis was observed in animals, with villi and intestinal glands preservation in the EPG group. The results suggest the safety and the bioactive effect of EPG, possibly related to its anti-inflammatory potential.