Quality and antioxidant properties of breads enriched with dry onion (Allium cepa L.) skin

Quinoa greens as a novel plant food: a review of its nutritional composition, functional activities, and food applications

Quinoa (Chenopodium quinoa Willd) is widely regarded as a versatile pseudo-cereal native to the Andes Mountains in South America. It has gained global recognition as a superfood due to its rich nutritional profile. While quinoa grains are well-known, there is an undiscovered potential in quinoa greens, such as sprouts, leaves, and microgreens. These verdant parts of quinoa are rich in a diverse array of essential nutrients and bioactive compounds, including proteins, amino acids, bioactive proteins, peptides, polyphenols, and flavonoids. They have powerful antioxidant properties, combat cancer, and help prevent diabetes. Quinoa greens offer comparable or even superior benefits when compared to other sprouts and leafy greens, yet they have not gained widespread recognition. Limited research exists on the nutritional composition and biological activities of quinoa greens, underscoring the necessity for thorough systematic reviews in this field. This review paper aims to highlight the nutritional value, bioactivity, and health potential of quinoa greens, as well as explore their possibilities within the food sector. The goal is to generate interest within the research community and promote further exploration and wider utilization of quinoa greens in diets. This focus may lead to new opportunities for enhancing health and well-being through innovative dietary approaches.

Diversity of the Morphometric and Biochemical Traits of Allium cepa L. Varieties

Several Allium cepa L. varieties, representing a versatile set of vegetables widely utilized by consumers, are appreciated for their bioactive properties, including antimicrobial, anticarcinogenic, and antioxidant capacities. The aim of this study is to compare the morphometric characteristics and biochemical profiles of four cultivars of A. cepa, two of them represented by the perennial Sicilian landrace "Cipudda agghiarola" (Allium × proliferum (Moench) Schrader), widely known as the Egyptian walking onion (WO), and by the landrace "Cipudduzza" belonging to the variety known as aggregatum (ON), which were compared with two commercial cultivars of A. cepa var. cepa (onion), Stoccarda (OS) and Rossa Carmen (OR). The experimental trial was conducted in Catania (Sicily), following organic growing practices. The randomized complete block experimental design was adopted with one experimental factor, the genotype (GE) effect. The harvested plants were characterized for their main morphometric parameters, according to the International Plant Genetic Resources (IGPR) descriptors. The biochemical activity was assessed by analyzing the total phenolic content (TPC) and the total flavonoid content (TFC). The antioxidant capacity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). The sugar profile (total sugars, sucrose, glucose, fructose, and fructooligosaccharides-FOS) and the volatile compounds by headspace-gas chromatography/mass spectrometry (HS-GC/MS) were also determined. The OR bulb exhibited the highest TPC (16.3 mg GAE/g d.w., p < 0.01) and TFC (8.5 mg QE/g d.w., p < 0.01), with the highest antioxidant capacity measured by the FRAP (27.1 µmol TE/g d.w., p < 0.01) and DPPH assays (46.2 µmol TE/g d.w., p < 0.01). The ON bulb showed the highest ORAC value (209 µmol TE/g d.w., p < 0.01). Generally, the bulbs were richer in sugars (584 mg/g d.w., p < 0.01) than the leaf blade (239 mg/g d.w., p < 0.01), except for OR. Significant interaction between the genotype and plant organ was noted in the volatile compound profiles (p < 0.05) except for total ketones and carboxylic acids, where higher content was observed in the leaf blade compared to the bulb, regardless of the genotype. These findings highlight WO's potential for use in ready-to-eat products, enhancing its market value.

Effect of ficin-hydrolyzed wheat gluten on bread quality and in vitro antioxidant activity before and after simulated gastrointestinal digestion

This study aimed to investigate the effect of adding ficin-hydrolyzed wheat gluten at different levels (0%, 1%, 2%, 4%) on bread quality, and in vitro antioxidant activity before and after simulated gastrointestinal digestion. Our findings revealed that the incorporation of the generated wheat gluten hydrolysates (WGH) up to 4 g per 100 g flour positively affected the technological and physical-chemical characterizations of breads, including dough rheological properties, color, specific volume, and moisture. The texture profile analysis indicated reductions in hardness, springiness, and chewiness of the breads, and confirmed anti-staling properties during storage. The enriched breads received satisfactory scores from the sensory panel and were perceived as less stale after a 4-day period of storage. The aroma score of the 4% WGH bread was significantly higher than other treatments. Regarding taste, the 4% WGH bread scored the lowest, but the obtained value was not statistically significant. The enriched breads exhibited DPPH, ABTS radical scavenging, and Fe2+ chelation abilities that increased in response to higher levels of hydrolysate incorporation, and these antioxidant activities were enhanced after simulated gastrointestinal digestion. Our findings confirm that it is possible to apply ficin-generated WGH to enhance physicochemical, nutritional, and biological quality of bread.

Development and quality evaluation of polyphenols enriched black carrot (Daucus carota L.) powder incorporated bread

Black carrot is a prominent source of polyphenols and the cheapest source of anthocyanins in India. In this study, an attempt has been made to examine the feasibility of black carrot powder as an ingredient in bread. Black carrot bread was prepared by incorporating different concentrations of black carrot powder (BCP) at 2.5, 5.0, 7.5 and 10 %. The developed bread samples were analyzed for physical and textural quality, proximate composition, bioactive compounds, antioxidant properties, sensory characteristics, mineral content and storage quality. The results revealed that loaf volume and specific volume decreased (1995-1254 mL, 5.25-3.28 mL/g) with the incorporation of BCP into bread. Textural analysis revealed that the addition of BCP led to increased hardness in the bread (0.110-12 0.151 N), whereas the resilience (43.64-35.10 %), cohesion and springiness (89.930-13 82.146 %) decreased significantly. The content of bioactive compounds such as total phenols, anthocyanins (29.63-112.68 mg/100 g) and flavonoids increased to exceptionally high levels in BCP-incorporated bread and showed high antioxidant activity. Incorporation of BCP up to 7.5 % showed the most acceptable sensory analysis score (7.85) with a significant increase in dietary fiber (40 %) and total mineral content (50 %), which revealed that black carrot powder could be used up to 7.5 % as an ingredient into bread with high acceptability. The present study revealed significant enhancement in bioactive compounds and mineral content of bread after the incorporation of black carrot powder, which supports its immense potential in preventing hunger and oxidative stress-induced disorders in developing countries.

Plant-Based Antioxidants in Gluten-Free Bread Production: Sources, Technological and Sensory Aspects, Enhancing Strategies and Constraints

The recognized contribution of antioxidant compounds to overall health maintenance and spotted deficiencies in celiac patients' diets has driven more intensive research regarding antioxidant compounds' inclusion in gluten-free bread (GFB) production during the last decade. The presented review gathered information that provided insights into plant-based antioxidant sources which are applicable in GFB production through the resulting changes in the technological, sensory, and nutritional quality of the resulting antioxidant-enriched GFB. The influence of the bread-making process on the antioxidant compounds' content alteration and applied methods for their quantification in GFB matrices were also discussed, together with strategies for enhancing the antioxidant compounds' content, their bioaccessibility, and their bioavailability, highlighting the existing contradictions and constraints. The addition of plant-based antioxidant compounds generally improved the antioxidant content and activity of GFB, without a profound detrimental effect on its technological quality and sensory acceptability, and with the extent of the improvement being dependent on the source richness and the amount added. The determination of a pertinent amount and source of plant-based antioxidant material that will result in the production of GFB with desirable nutritional, sensory, and technological quality, as well as biological activity, remains a challenge to be combated by elucidation of the potential mechanism of action and by the standardization of quantification methods for antioxidant compounds.

Agro-industrial by-products as ruminant feed: Nutritive value and in vitro rumen fermentation evaluation

In recent years, agricultural by-products have generated increasing interest as ruminant feed. In a completely randomized design with five experimental treatments, this in vitro study investigated the nutritional value of citrus pulp and onion peel as alternative feed for ruminants and their effects on rumen fermentation, digestibility, and gas production. The first group was the control (50% grass hay/50% concentrate mixture). The other four treatments represented citrus pulp and onion peel at inclusion levels of 10 and 20%, replacing the expensive, high-quality feed ingredients such as the concentrate mixture. The chemical composition showed that citrus pulp is an energy-rich material that could be included up to 20% to replace part of the concentrate in a mixed diet without any adverse impacts on rumen fermentation parameters. The onion peels were rich in fiber and minerals. Their inclusion in the diet of over 10% had detrimental effects on rumen fermentation. The inclusion of either citrus pulp or onion peel in the diet did not have the potential to reduce enteric methane production. In conclusion, citrus pulp showed promising results as a new feed for ruminants. It was effective when included in up to 20% of a ruminant diet, replacing the concentrate mixture.

Walnut Male Flowers (Juglans regia L.) as a Functional Addition to Wheat Bread

The aim of this study is to assess the effect of adding dried and ground walnut male flowers to wheat flour on selected physicochemical and antioxidant properties of the obtained wheat bread. The control sample was bread without the addition of walnut male flowers. In the tests, the addition of flowers was used in the amounts of 0.5%, 1.0%, 1.5%, 2.0% and 2.5% of the weight of the flour used in the control sample. Bread dough was prepared according to the direct method with the use of yeast. The parameters of the baking process of the control bread and of the test bread were calculated. The selected parameters determining the quality of the obtained bread, including the loaf volume, the specific volume, the crumb porosity, the crumb texture and the color were measured. The antioxidant potential and total polyphenol content were tested both in the dough and in the bread. The test results were analyzed statistically. It was found that the partial replacement of wheat flour with walnut male flowers resulted in a significant reduction in the loaves' volume and in the darkening of both the color of the dough and the crumb. The value of the L* parameter decreased with the increasing addition of walnut flowers. The lowest values of this parameter were found to be 53.87 (crust) and 39.94 (crumb) in the sample with 2.5% addition. The average volume of the loaves ranged from 565 cm³ (0.5%) to 675 cm³ (control). The use of the additive in the amount of 2.5% caused significant changes in the values of most of the examined parameters of the bread crumb texture. The addition of walnut male flowers to the flour had a significant effect on the antioxidant potential and the total polyphenol content of the tested doughs and breads. In the case of bread, the total polyphenol content value ranged from 96.90 mg GAE/g dw to 208.08 mg GAE/g dw. Similarly, the antioxidant potential increased with increasing walnut male flower supplementation. The antioxidant potential determined by the ABTS and FRAP methods ranged from 1.42 mmol TE/g dw to 2.02 mmol TE/g dw and from 0.08 mmol TE/g dw to 0.33 mmol TE/g dw, respectively. The obtained research results prove the application potential of walnut flowers in the design of food, with beneficial pro-health properties, and are an example of the use of plant by-products in the process of food enrichment.

Red onion skin active ingredients, extraction and biological properties for functional food applications

Onion is an important vegetable in the world and the second most important vegetable crop after tomato.Hence, the onion waste, such as onion skin, is produced in abundance causing environmental problems. Due to its bioactive compounds, especially phenolics and flavonoids, red onion skin can be used through appropriate methods for producing value-added products. These phytochemicals are proven to prevent oxidative stress and broad spectrum of microorganisms beside having diverse beneficial biological properties. Extraction step is the most critical processing in making phytonutrient available. Various approaches including conventional and non-conventional technologies applied for extracting different compounds from red onion wastes was summarized in this study. To evaluate the industrial application potential, the use of natural bioactives derived from red onion skin for elaboration of various food systems has been also investigated.

Novel Approaches in the Valorization of Agricultural Wastes and Their Applications

Worldwide, a huge amount of agricultural food wastes and byproducts containing valuable bioactive compounds are generated, especially throughout the entire supply chain. Minimizing food wastes and byproducts is the first option to avoid environmental problems, and to help the economy and the society. Although many countries implement policies to reduce food wastes and byproducts, and different management methods are available to utilize agricultural food wastes, they are still produced annually. Nanotechnological and biotechnological approaches are recently used as novel and green applications to valorize agricultural food wastes and improve their stability and applicability. In this Review, these approaches are covered in detail with given examples. Another valorization way of consumable food waste is using it for functional food production. This Review focuses on specific examples of functional foods with food waste as an ingredient. In addition, the problems and limitations of waste management and valorization methods are investigated, considering future perspectives.

Development and evaluation of onion bulb descaler for removal and collection of surface dry peel

Onion bulbs contain outer papery dry peel which is rich with industrially important high-value compounds. Removal of dry peel/scale of onion is the common practice during bulb processing, storage and marketing. A conventional manual method of scale removal involves huge labour, drudgery and means of environmental pollution. An onion descaler machine has been therefore developed to mechanize this operation, reduce drudgery and effectively collect the dry scales for industrial use. The operating parameters of the developed machine were optimized for its best performance using RSM. During optimization study, roller speed, roller slope and hopper opening were taken as independent variables. The performance of the machine was evaluated through descaling efficiency and descaling loss. During experimentation, descaling efficiency and descaling loss were obtained in the range of 35.92-98.55% and 0.82-9.07%. The optimum performance of the machine was obtained at 450 rpm roller speed, 2% roller slope and 380 mm of the hopper opening with maximum descaling efficiency (88.29%) and minimum descaling loss (3.65%). The optimization of the onion descaler parameters and their statistical relation provided the necessary information on the combination of material-machine alignment, and design parameters for enhanced descaling efficiency.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-021-05264-5.

Effects of molecular characteristics and microstructure of amaranth particle sizes on dough rheology and wheat bread characteristics

The aim of this research is to investigate the molecular features and microstructure of amaranth flour (AF) fractions and their partial replacement effect of wheat flour (WF) on the chemical composition, dough dynamic rheology, technological and sensory characteristics of bread. The microstructure and molecular characteristics of AF were depending on their particle size (PS). When WF replacement increased and PS decreased the composite flour was richest in protein, lipids, and ash, while the moisture and carbohydrates of these flours decreased. Dynamic rheological behavior revealed significant variations depending on PS and replacement level. Bread volume and firmness increased when more than 15% AF from large PS replaced WF, while medium and small PS at 5–15% replacements was increased the loaf porosity. Chroma values decreased and samples became darker when the replacement level increased. Moreover, replacement of WF with various AF fractions impacted bread sensory characteristics, obtaining better acceptance for large and medium PS up to 10%.

Recent advances in research on Allium plants: functional ingredients, physiological activities, and applications in agricultural and food sciences

Fruits and vegetables (FVs) have long been a major source of nutrients and dietary phytochemicals with outstanding physiological properties that are essential for protecting humans from chronic diseases. Moreover, the growing demand of consumers for nutritious and healthy foods is greatly promoting the increased intake of FVs. Allium (Alliaceae) is a perennial bulb plant genus of the Liliaceae family. They are customarily utilized as vegetable, medicinal, and ornamental plants and have an important role in agriculture, aquaculture, and the pharmaceutical industry. Allium plants produce abundant secondary metabolites, such as organosulfur compounds, flavonoids, phenols, saponins, alkaloids, and polysaccharides. Accordingly, Allium plants possess a variety of nutritional, biological, and health-promoting properties, including antimicrobial, antioxidant, antitumor, immunoregulatory, antidiabetic, and anti-inflammatory effects. This review aims to highlight the advances in the research on the bioactive components, physiological activities and clinical trials, toxicological assessment for safety, and applications of different Allium plants. It also aims to cover the direction of future research on the Allium genus. This review is expected to provide theoretical reference for the comprehensive development and utilization of Allium plants in the fields of functional foods, medicine, and cosmetics.

A review of anti-inflammatory, antioxidant, and immunomodulatory effects of Allium cepa and its main constituents

CONTEXT

Allium cepa L. (Liliaceae), known as onion, is consumed throughout the world. Onion and its derivatives including saponins, aglycones, quercetin, cepaenes, flavonoids, organosulfurs, and phenolic compounds, showed various pharmacological properties and therapeutic effects.

OBJECTIVE

Anti-inflammatory, antioxidant, and immunomodulatory effects of A. cepa and its main constituents, along with the underlying molecular mechanisms are presented.

METHODS

Databases including, Web of Knowledge, Medline/PubMed, Scopus, and Google Scholar were checked for articles published between 1996 and the end of July 2020, using the key-words Allium cepa, quercetin, anti-inflammatory, antioxidant and immunomodulatory.

RESULTS

A. cepa and its constituents mainly quercetin showed anti-inflammatory effects mediated via reduction of total and differential WBC counts, inhibition of chemotaxis of polymorphonuclear leukocytes, COX, and LOX pathways and prevented formation of leukotrienes and thromboxanes, prostaglandin E2 (PGE2) as onVCAM-1, NF-κB, MARK,d STAT-1, JNK, p38 and osteoclastogenesis. A. cepa and its derivatives showed antioxidant effect by decreasing lipid peroxidation, NAD(P)H, MDA, NO, LPO and eNOS but enhancing antioxidants such as SOD, CAT, GSH, GPx, GSPO, TrxR, SDH, GST and GR activities and thiol level. Immunomodulatory effects of the plant and quercetin was also shown by reduction of Th2 cytokines, IL-4, IL-5, and IL-13 as well as IL-6, IL-8, IL-10, IL-1β and TNF-α and IgE levels, but increased CD4 cells, IFN-γ level and IFN-γ/IL4 ratio (Th1/Th2 balance).

CONCLUSIONS

The effect of onion and its constituents on oxidative stress, inflammatory and immune system were shown indicating their therapeutic value in treatment of various diseases associated with oxidative stress, inflammation, and immune-dysregulation.

Changes in Antioxidant Properties and Amounts of Bioactive Compounds during Simulated In Vitro Digestion of Wheat Bread Enriched with Plant Extracts

Cereal preparation can be an excellent source of substances with proven health-promoting properties. Unfortunately, some types of bread, such as white flour bread, are devoid of many valuable nutrients. Therefore, it is necessary to look for ways to increase its density and nutritional value. The aim of the study was to investigate the effect of stabilized plant extracts on the quality of bread, its antioxidant activity and polyphenol content, and to evaluate the stability of bioactive compounds and antioxidant activity during in vitro digestion. The research material was the wheat bread baked with spray dried microcapsules of hawthorn bark, soybeans and onion husks in maltodextrin or inulin carriers. The addition of plant extracts resulted in the presence of phenolic compounds in the wheat bread, and its antioxidant activity significantly increased. There was no significant difference in antioxidant activity between breads containing microcapsules with different carriers. During in vitro digestion, procyanidins and isoflavones in bread were more resistant to the digestive processes than other compounds. The antioxidant activity during simulated digestion was the highest at the stage of gastric digestion, and its value depended on the extract used and the analytical method applied.

Effects of Curculigo pilosa supplementation on antioxidant and antidiabetic activities of yam flour

The practice of using nutritional knowledge to enhance the general health of the populace forms the basis of food fortification. In this study, an antioxidant-rich Curculigo pilosa is substituted (1, 3, 5 and 10%) into yam tuber flour with the aim of improving the antidiabetic and antioxidant properties of the yam tuber flour. Antioxidant property was evaluated by polyphenol contents, ascorbic acid content, reducing effects, scavenging activity and inhibition of linoleic acid peroxidation. Antidiabetic activity was assessed by inhibition of α- amylase and α- glucosidase enzymes. The antioxidant property was significantly (p < 0.05) enhanced; also, the ability of the sample to inhibit the activity of α- amylase and α- glucosidase enzymes were significantly (p < 0.05) enhanced by supplementation with Curculigo pilosa. The profiling of the samples by High Performance Liquid Chromatography revealed some proven antioxidant and antidiabetic agents which were enhanced in supplemented yam flour. It can be concluded from the results obtained in this study that Curculigo pilosa powder could be a promising functional ingredient for yam flour in the management of diabetes and other oxidant-related diseases.

Micronized Oat Husk: Particle Size Distribution, Phenolic Acid Profile and Antioxidant Properties

Oat husk (OH; hull) is a by-product generated from oat processing and is rich in insoluble fibre and phenolic compounds. The aim of this work was to study the particle size distribution, antioxidant activity, and phenolic profile of micronized OH. For this purpose, the hull was first sterilized using superheated steam and was then ground using an impact classifier mill. The particle size distribution (PSD) of the ground husk was determined using the laser diffraction method and the parameters characterizing the PSD of the ground husk, and its antioxidant activity were calculated. In addition, UPLC-MS/MS analysis of phenolic acids was also performed. Micronization of the sterilized husk effectively decreased the size of the particles, and with the increasing speed of the rotor and classifier, the median size of the particles (d50) decreased from 63.8 to 16.7 µm. The following phenolic acids were identified in OH: ferulic, caffeic, p-hydroxybenzoic, vanillic, syringic, and synapic acid. Ferulic acid constituted about 95% of total phenolic acids. The antioxidant activity of the obtained extracts increased as the particle size of the micronized husk decreased. The highest half maximal inhibitory concentration (EC50 index) was found for chelating power, and the lowest was found in the case of radical scavenging activity against DPPH.

Hemp (Cannabis sativa L.) Flour-Based Wheat Bread as Fortified Bakery Product

Hemp flour from Dacia Secuieni and Zenit varieties was added to bread in different proportions (5%, 10%, 15% and 20%) to improve its nutritional properties. The purpose of this paper was to present the advanced nutritional characteristics of these bread samples. The selected varieties of hemp, accepted for human consumption, met the requirements for the maximum accepted level of THC in seeds. The protein content of new products increased from 8.76 to 11.48%, lipids increased from 0.59 to 5.41%, mineral content from 1.33 to 1.62%, and fiber content from 1.17 to 5.84%. Elasticity and porosity decreased from 95.51 to 80% and 78.65 to 72.24%, respectively. K, Mg, Ca, P, Mn and Fe are the main mineral substances in bread with addition of hemp flour from the Dacia Secuieni and Zenit varieties. The total amount of unsaturated fatty acids in the bread samples with hemp flour ranged from 67.93 g/100 g and 69.82 g/100 g. Eight amino acids were identified, of which three were essential (lysine, phenylalanine, histidine). Lysine, the deficient amino acid in wheat bread, increased from 0.003 to 0.101 g/100 g. Sucrose and fructose decreased with the addition of hemp flour, and glucose has not been identified. The amount of yeasts and molds decreased in the first 3 days of storage. Regarding the textural profile, the best results were obtained for the samples with 5% addition. In conclusion, bread with the addition of hemp flour has been shown to have superior nutritional properties to wheat bread.

The Oleaster (Elaeagnus angustifolia): A Comprehensive Review on Its Composition, Ethnobotanical and Prebiotic Values>

BACKGROUND

Oleaster or Elaeagnus angustifolia is a deciduous plant from Elaegnacea family and is well-known for its remedial applications.

OBJECTIVE

This paper presents a comprehensive review of the potential application of Oleaster's flour incorporated in some food products. Emphasis is given to the physicochemical, biochemical, and functional properties of Oleaster's flour.

METHODS

A comprehensive search was carried out to find publications on Oleaster's flour and its application as a prebiotic. The results of the related studies were extracted and summarized in this paper.

RESULTS

Oleaster's flour as a prebiotic ingredient enhances antioxidants, polyphenols, fiber, flavonoids, Sterols, carbohydrates, and protein content of food products.

CONCLUSION

Further advanced investigations on Oleaster and its functional ingredients revealed that these are efficacious and can be applied as a substitute source in pharmacological industries for medical applications.

Waste streams in onion production: Bioactive compounds, quercetin and use of antimicrobial and antioxidative properties

Onion production generates abundant waste with high contents of bioactive compounds. These might have several beneficial functional properties for fortification of foods. To understand the variety and potential for further use, we examined various parts of the plants (edible/inedible waste/outer skin of onion), as well as extraction in water/ethanol and by shaking/sonication. Quercetin content and antioxidant capacity were initially determined for extracts of edible and waste parts of red, yellow and white onions, and red shallots. Ethanol extracts of the waste fraction had the highest quercetin content and antioxidant capacity. Except white onion, which contained no quercetin, the dried waste ethanol extracts contained up to 15 mg quercetin g^-1 and had an antioxidant capacity of nearly 40 mg Trolox equivalents g^-1. Furthermore, the dried skin ethanol extract of yellow onion, which is commercially the most available fraction, contained 8 mg quercetin g^-1, with antioxidant capacity of 25 mg Trolox equivalents g^-1 and high antimicrobial activity. Dried yellow onion skin showed good stability for the quercetin content under various storage conditions (4, 25, 37, 40 °C; dark/light; dry/moist air/in water). Bacteria, bacterial spores, yeast and mould counts remained unchanged for dried onion skin over 5 days under storage conditions that can promote food spoilage, indicating exceptional microbial stability. Finally, two different applications are demonstrated for dried yellow onion skin: tablets for home use (tablets as more convenient form of storage and for simple dosing in cooking), and a stabilisation additive (prolonged shelf-life of olive oil). Both represent efficient and straightforward approaches through waste prevention and food fortification.

Nutrient Composition and Antioxidant Performances of Bread-Making Products Enriched with Stinging Nettle (Urtica dioica) Leaves

Stinging nettle (Urtica dioica) is an edible plant, well-known for its nutritional and nutraceutical properties. Stinging nettle leaves are typically rich in fibers, minerals and vitamins, as well as antioxidant compounds, i.e., polyphenols and carotenoids. Due to these reasons, since ancient times stinging nettle has been widely used in Italy as an ingredient in foods and beverages as a therapeutic agent. This work provides an investigation focused on bread enrichment with nettle leaves and the improvement of bread proximate composition in minerals, fibers and antioxidant compounds during product preparation. The comparison between plain and nettle enriched white bread shows a significant increase in fibers and nutrients, i.e., calcium and copper levels. Nettle enrichment also provides an increase in lutein and β-carotene, as well as in total phenols and antioxidant activity. These last two nutritional elements are remarkably high in enriched bread and it has been found that phenolic concentration increases during breadmaking steps, from kneading to primary dough fermentation and from secondary fermentation of shaped loaves to baking.

Antioxidant and the ameliorating effect of Allium cepa (Onion) fortified feed against potassium bromate induced oxidative damage in Wistar rats

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Allium cepa fortified feed protected against oxidative damage by potassium bromate.

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Malondialdehyde (MDA) levels in the hepato-renal declined significantly in rat fed fortified feed.

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Histo-architectural of hepato-renal cells were restored to near normal following the administration of fortified feed.

Allium cepa Linn (Onion) Organosulfuric compounds and phytonutrients have medicinal benefits. The study estimated the antioxidant effect of Allium cepa in fortified feed against oxidative damage caused by potassium bromate. Commercial feed was fortified by substituting 10 %, 20 %, and 30 % of rat's daily ration with the respective portion of pulverized Allium cepa. Potassium bromate was administered orally to the rats in all the groups except rats in the normal control. The rats in the test groups were allowed access to the fortified feed ad libitum. The animals were sacrificed; consequently, the serum, liver, and kidney were obtained for biochemical assay and histological assessment. The percentage composition of some amino acids and some proximate were higher in the fortified feed. Furthermore, Malondialdehyde (MDA) level in the liver, kidney, and serum decreased significantly (P ≤ 0.05) in rats fed with fortified feed compared to administered only Potassium bromate. Similarly, the concentration of total protein increased significantly (P ≤ 0.05) in the liver, kidney, and serum of the animals fed with fortified feed. The hematology result was normal in rats fed with fortified feed. The liver and kidney cell architecture was normal in animals fed with fortified feed. Allium cepa may have conferred protection and amelioration to oxidative damage by potassium bromate in rats.

Enhancing the Nutritional Properties of Bread by Incorporating Mushroom Bioactive Compounds: The Manipulation of the Pre-Dictive Glycaemic Response and the Phenolic Properties

Wheat bread supplemented with mushroom powder from three different species of mushrooms was investigated in terms of starch characteristics (content, gelatinisation, and digestibility) and antioxidant capacities. The decrease in total starch contents, and increase in phenolic contents of the breads, were associated with increased mushroom powder contents. Mushroom inclusion reduced the rate of reducing sugar released over 120 min in an in vitro digestion compared to the control sample, implying a lower area under the curve (AUC) value with the inclusion of mushroom powder and a potentially lower predicted glycaemic response of the bread. Mushroom powder incorporation also enhanced the DPPH radical scavenging assay and oxygen radical absorbance capacity (ORAC) compared to control bread. The action of the addition of different mushroom powders on the bread crust and crumb microstructure properties was also studied. Mushroom powder altered the internal microstructure of the bread crust and crumb by affecting the interactions between starch and the other components of the bread. Overall, this shows that mushroom powder could be added to bread to deliver health benefits to consumers.

Dough rheology, antioxidants, textural, physicochemical characteristics, and sensory quality of pizza base enriched with onion (Allium cepa L.) skin powder

In the present research, wheat flour was replaced with onion skin powder (OSP) in 2%, 3.5%, and 5% concentration along with control to produce different pizza base variants. Prepared pizza doughs and base were investigated for different quality parameters. Rheology revealed that increased concentration of OSP elevated the storage modulus (G') (solid nature) of pizza doughs. Colour measurement of both the doughs and pizza base exhibited lightness in control (L* 86.46 ± 0.39) and darkness in 5% OSP variant (L* 46.43 ± 0.69). Physicochemical investigation showed no significant difference however, a gradual increase was obtained in fiber, water, and oil holding capacity of pizza base. Texture properties showed that the addition of OSP imparted an increased trend of hardness i.e. 5% OSP variant had maximum hardness (14.87 ± 0.20 N). A higher level of total phenols, total flavonoids, and antioxidant activity was obtained in fortified products, which exhibits onion skin as a natural source of antioxidants for functional foods. Sensory evaluation revealed OSP 2% as the most accepted variant in terms of overall acceptability. The storage study of the pizza base revealed that controlled environment was the best-suited atmosphere for a longer shelf-life of pizza base.

Biological activity, phytochemical parameters, and potential bioaccessibility of wheat bread enriched with powder and microcapsules made from Saskatoon berry

The aim of the present study was to determine the impact of Saskatoon powder addition on phytochemical parameters, biological activity, and nutritional value of wheat bread. Supplementation increased phenolics content up to 72% in the bread with 6% powder content. This increase was reflected in the improved antioxidative properties of breads, especially after their supplementation with the microencapsulated additives (an increase by 93% in the bread enriched with 6% of powder covered with maltodextrin). The in vitro digestion released the antioxidative compounds, leading to higher bioaccessibility of the breads enriched with the microencapsulated powders. The highest inhibition of activities of cyclooxygenase 1 and -2, as well as amylase and glucosidase was recorded for the breads enriched with the additive microencapsulated with maltodextrin and inulin. Thus, Saskatoon berry powders, especially the microencapsulated ones, may be used as functional components in designing innovative bakery products.

Effects of processing on onion skin powder added extrudates

It is possible to enhance the functional properties of extruded products with the inclusion of fruit and vegetable by-products. Onion skin, a rich source of quercetin and fiber, is considered as waste in the industry and can be used as an alternative ingredient to improve the nutritional value of the extruded products. Three levels (3, 6, and 9%) of onion skin powder (OSP) were added to wheat flour and compared with control (0% OSP). The effect of the extrusion process on accessible quercetin, total phenolic content, and antioxidant activity of the samples were investigated. In addition, carbohydrate digestibility analyses were conducted for the products. Mass spectrometry (LC-MS/MS) results indicated that increasing the OSP level increased the quercetin content. The process caused the release of the entrapped quercetin from OSP, which was revealed by significantly higher quercetin levels for the extrudates. Some of the quercetin was lost during in vitro digestion process. Increasing the OSP level increased antioxidant activity and total phenolic contents of the samples. Total phenolic contents decreased significantly after the processing, yet antioxidant activities were not affected. The extruded products showed high amounts of rapidly available glucose (69.5 g/100 g). The OSP enhancement did not change the carbohydrate digestibility of products. The results indicated that the extrusion process could increase the level of accessible bioactive ingredients, and the level of functional compound addition can be optimized further.

Red bell pepper (Capsicum annuum L.): Optimization of drying conditions and preparation of functional bread

The aim of this study was to optimize the drying conditions (pretreatments and drying temperatures) of red bell pepper to obtain red bell pepper powder (RBP) with maximum bioactive retention and assess its potential use as a functional ingredient in bread. The RBP pretreated (blanching + dipping in ascorbic and citric acid solution) and dried at 60 °C retained the highest bioactive compounds. Wheat flour blends were prepared with RBP at 0%, 2%, 4%, 6%, 8%, and 10% level of incorporation and among hydration properties, water absorption increased with increasing levels. The prepared breads were assayed for physical, nutritional, bioactive, and sensory characteristics. Bread supplementation with RBP improves its color, mineral, fiber, and bioactive properties. However, the texture of bread becomes hard with the increased level of RBP due to a decrease in specific volume. The significant increment was recorded for bioactive compounds, such as total phenols, antioxidant activity, flavonoids, and carotenoids as the level of powder increased. Bread enriched with 6% RBP showed highest sensory scores (8.45) and index of acceptability (87.83%) as compared to other breads. Thus, RBP acts as a valuable supplement for developing bread with improved nutritional and bioactive constituents. PRACTICAL APPLICATION: This study describes the effect of different pretreatments and drying temperatures for processing of RBP as a functional ingredient in bread, being a staple food around the world. RBP powder is a novel ingredient that improved the nutritional, bioactive, and appearance of bread. Hence, it will be helpful in the utilization of perishable crops like bell pepper and will demonstrate its commercial viability to improve the nutritive value of bakery products.

Effects of edible plant polyphenols on gluten protein functionality and potential applications of polyphenol-gluten interactions

Expanding plant-based protein applications is increasingly popular. Polyphenol interactions with wheat gluten proteins can be exploited to create novel functional foods and food ingredients. Polyphenols are antioxidants, thus generally decrease gluten strength by reducing disulfide cross-linking. Monomeric polyphenols can be used to reduce dough mix time and improve flexibility of the gluten network, including to plasticize gluten films. However, high-molecular-weight polyphenols (tannins) cross-link gluten proteins, thereby increasing protein network density and strength. Tannin-gluten interactions can greatly increase gluten tensile strength in dough matrices, as well as batter viscosity and stability. This could be leveraged to reduce detrimental effects of healthful inclusions, like bran and fiber, to loaf breads and other wheat-based products. Further, the dual functions of tannins as an antioxidant and gluten cross-linker could help restructure gluten proteins and improve the texture of plant-based meat alternatives. Tannin-gluten interactions may also be used to reduce inflammatory effects of gluten experienced by those with gluten allergies and celiac disease. Other potential applications of tannin-gluten interactions include formation of food matrices to reduce starch digestibility; creation of novel biomaterials for edible films or medical second skin type bandages; or targeted distribution of micronutrients in the digestive tract. This review focuses on the effects of polyphenols on wheat gluten functionality and discusses emerging opportunities to employ polyphenol-gluten interactions.

Quality of New Functional Powdered Beverages Enriched with Lyophilized Fruits—Potentially Bioaccessible Antioxidant Properties, Nutritional Value, and Consumer Analysis

This study evaluates nutrients and health-promoting compounds responsible for antioxidant capacity in eight novel formulations based on lyophilized fruit and vegetable powders. The composition contained lyophilized carrot, pumpkin, lentil sprouts, raspberry, strawberry, and apple. The effect of functional additives on the antioxidant, nutritional, and functional characteristics of powdered beverages was determined in the powders and after rehydration followed by in vitro digestion. The antioxidant activity, phenols, vitamin C, and reducing power were significantly higher in the powders enriched with additives having potential functional properties. Furthermore, the analyses indicated that all the powdered formulations may be potential sources of total starch (100–112 mg/100 mL) and proteins (125–139 mg/100 mL). The designed powdered beverages after reconstitution exhibited high antioxidant content, reasonable consumer acceptance, and good in vitro bioaccessibility. The best results of antioxidant capacity were obtained for beverages enriched with raspberry, i.e., 10.4 mg Trolox equivalent (TE)/100 mL and 12.1 mg TE/100 mL rehydrated at 20 °C and 80 °C, respectively. Additionally, color characteristics were used as indicators of the quality of the powdered beverages. This research promotes the reduction of food waste, since whole plant tissues are used, thus allowing maximum exploitation of food raw materials; moreover, drying provides stable shelf life.

Influence of onion skin powder on nutritional and quality attributes of wheat pasta

Onion skin is a waste produced during onion bulb processing. Recent studies have reported that it contains large amounts of bioaccessible and bioavailable compounds thus it can be used to design of novel food products. The objective of the study was an attempt to substitute semolina with onion skin (OS) powder in pasta at 2.5, 5 and 7.5 g/100 g levels. The effects on the chemical composition, antioxidant potential, technological and sensory properties of the fortified pasta samples were evaluated compared with a control sample. Fortification with OS resulted in a significant (P < 0.05) improvement in nutritional properties, which was demonstrated by an increase in the content of dietary fibre, ash, total phenolic compounds, flavonoids content and antioxidant activity (FRAP and DPPH). Cooking loss increased with increasing levels of OS, however, all pasta samples were in the acceptable range (8 g/100 g). Onion skin incorporation decreased optimal cooking time, water solubility index and increase redness (a*), compared to the control sample. Results of sensory evaluation suggest that pasta, in which 2.5% of the flour was replaced by this plant component, showed the highest value of the “overall quality”. Our study indicates that onion skin powder can be a potential alternative for the food industry to provide nutritional enriched pasta.

Possibility to Save Water and Energy by Application of Fresh Vegetables to Produce Supplemented Potato-Based Snack Pellets

The aim of the study was to examine the effect of fresh vegetable addition on processing efficiency, and to ascertain the energy and water consumption during production of potato-based snack pellets. The extrusion-cooking process with a modified single screw extruder was applied at variable screw speeds and amounts of vegetable additives. A mixture of potato flakes, potato grits and starch was used as a basic recipe. The potato composition was supplemented with fresh pulp of onion, leek, kale and carrot in amounts of 2.5–30.0% as replacement of a related amount of potato starch. The water consumption, as well as processing indicators: the production efficiency, the specific mechanical energy (SME), and the total SME requirements during snack pellets processing at the laboratory scale were evaluated. As a result of this work, we found that the amount of applied vegetable additives had little impact on both processing efficiency and SME depending on the screw speeds applied. Moreover, we saw increased processing efficiency with increased screw speed during extrusion. Of particular note, maximum value of processing efficiency was observed if fresh onion was used as an additive at the highest speed screw. Furthermore, the lowest specific mechanical energy consumption was noted for extrudates supplemented with fresh onion addition processed at the lowest screw speed. The most important limiting of water consumption during processing without negative effects on processing efficiency and quality of the final snack pellets was observed if 20% to 30% of fresh vegetables were used in the recipe. We believe that application of fresh vegetable pulp limited the energy requirements by mitigating the drying process of additives.

Effects of celery powder on wheat dough properties and textural, antioxidant and starch digestibility properties of bread

In order to investigate the effects of celery powder (CP) on bread quality, wheat flour was replaced by CP which was produced from two celery varieties ('Jinnan Shiqin' and 'Ventura') at different levels (1, 2, 3 and 5/100 g flour). For both kinds of CPs, Mixolab analysis showed that the water absorption of dough increased with the increase of CP, while the protein network weakening (C2), peak viscosity (C3) and crystallinity of starch (C5-C4) decreased. The specific volume of bread decreased at higher CP level, whereas its crumb hardness and chewiness showed a reverse trend. The addition of CP significantly increased the total phenolics content of bread, and thus caused a significant improvement in antioxidant activities. The addition of CP significantly reduced the content of rapidly digestible starch in bread, while the contents of slowly digestible starch and resistant starch were increased. Additionally, bread prepared with a higher CP content showed a lower predicted glycaemic index. Based on the results of sensory analysis, bread incorporated with 2 g/100 g flour for 'Jinnan Shiqin' or 1 g/100 g flour for 'Ventura' didn't show significant effect on its overall acceptability. The present study indicated that addition of CP could be an effective way to produce a bread with higher antioxidant activity and lower starch digestibility.

Mixolab behavior, quality attributes and antioxidant capacity of breads incorporated with Agaricus bisporus

At present, some breads rich in edible mushrooms are more popular to meet the needs of functional bread products. In this study, different proportions of Agaricus bisporus powder (0, 2, 4, 6, 8%) were added into wheat flour to prepare bread, and their Mixolab behavior, bread quality and antioxidant capacity were studied. The results showed that the addition of Agaricus bisporus powder diluted the gluten in the flour, destroyed the dough matrix, which changed the water absorption of dough, the gelatinization and retrogradation of starch on the Mixolab. Meanwhile, the results of specific volume, texture and color measurement showed that addition of Agaricus bisporus powder reduced the specific volume of bread, deteriorated the texture and darkened the crumbs. In addition, the higher proportion of Agaricus bisporus powder, the higher total phenolics content and antioxidant ability of compound bread. However, sensory analysis showed that the overall acceptability of breads was relatively high after adding a small amount of Agaricus bisporus powder. Our results showed that breads containing about 4% Agaricus bisporus powder had higher antioxidant capacity and better sensory acceptability.

Onion skin extract as a protective agent against oxidative stress in Saccharomyces cerevisiae induced by cadmium

Onion skin extract is a source of bioactive compounds demonstrating a high antioxidant activity. The purpose of this research was to investigate the effect of onion skin extract at the level of oxidative stress markers in Saccharomyces cerevisiae exposed to cadmium. The generation of reactive oxygen species (ROS), antioxidant enzymes activity, total content of glutathione, and the level of lipid peroxidation in yeast cells were determined. Research showed that onion skin extract protected the yeast cells from the occurrence of oxidative stress induced by cadmium. Cells treated with onion skin extract and cadmium were characterized by lower generation of ROS, antioxidant enzymes activity, lipid peroxidation, and higher level of glutathione content than cells treated with cadmium only. However, the protective effect was dependent on the onion skin extract concentration in yeast medium. PRACTICAL APPLICATIONS: The presented studies are of comprehensive character regarding antioxidant properties of the onion skin extract, using Saccharomyces cerevisiae as a model organism. The research results give the opportunity to conduct further research on the use of onion skin extract in functional food or dietary supplements production, as a cellular protector against negative consequence of oxidative stress. It should also be mentioned that the major research material was onion skin which is a troublesome waste material for onion producers. Consequently, the study result will, to a certain extent provide an opportunity to increase interest in the problem of rational use of the waste material, according to a sustainable development idea.

Impact of Interactions between Ferulic and Chlorogenic Acids on Enzymatic and Non-Enzymatic Lipids Oxidation: An Example of Bread Enriched with Green Coffee Flour

This study investigated the activity, mode of inhibition, and interactions between lipoxygenase (LOX) inhibitors and compounds able to inhibit lipids oxidation (LPO) derived from green coffee beans (GCBs), wholemeal wheat flour (WF), and bread enriched with GCB, in comparison with pure chemical standards of the main active components—ferulic (FA) and chlorogenic acids (CGA). Both GCB and WF contain potentially bioaccessible and bioavailable LPO inhibitors acting synergistically. Both FA and CGA presented nearly additive interaction. Potentially bioaccessible LOX inhibitors from GCB and WF acted synergistically, whereas moderate antagonism was found for potentially bioavailable compounds. The activity of CGA and FA was quite similar (EC50 = 18.56 and 22.36 g DW/ml, respectively) and synergistic action between these components was found. The LPO activity of functional breads was positively correlated with the percentage of GCB (R2 = 0.98). Ferulic acid and CGA acted as competitive LOX inhibitors, whereas potentially bioaccessible compounds from bread enriched with GCB demonstrated an uncompetitive mode of action. Green coffee beans, WF, and the proposed functional product could be helpful in dietary therapy and prevention of so-called lifestyle disorders related with the lipid metabolism. Moreover, this paper highlights the need to study the interactions between the active ingredients of newly designed functional products.