Phenolic Acid Content and Antioxidant Properties of Extruded Corn Snacks Enriched with Kale

Fresh Chokeberry (Aronia melanocarpa) Fruits as Valuable Additive in Extruded Snack Pellets: Selected Nutritional and Physiochemical Properties

In this paper, the nutritional value and (selected) physiochemical properties of extruded snack pellets enriched with fresh chokeberry (Aronia melanocarpa) fruits were analyzed from the perspective of being a new product for the functional food sector. The purpose of this study was to determine the effect of the addition of fresh chokeberry and variation in content and screw speed on extruded snack pellet basic compositions, fatty acid profiles, antioxidant activity, as well as water absorption and solubility indexes, fat absorption and color profiles. The obtained results revealed a significant increase in antioxidant activity for all samples (above 90% of free radical scavenging) in comparison to potato-based control samples (just over 20% of free radical scavenging). The total phenolic content assay revealed the most valuable results for samples enriched with 30% chokeberry, while Ultra Performance Liquid Chromatography (UPLC) analysis allowed the determination of the most important phenolic acids. Of interest, chokeberry addition decreased the fat absorption index (FAI) after expansion by frying. Moreover, the highest values of crude protein and crude ash were observed in snack pellets supplemented by the application of 30% chokeberry. In such samples, the crude protein content was at the level of 4.75-4.87 g 100 g-1 and crude ash content at 4.88-5.07 g 100 g-1. Moreover, saturated fatty acids (SFA) content was lower in snack pellets with chokeberry addition, and increasing the amount of chokeberry additive from 10% to 30% in extruded snack pellet recipes resulted in more than double an increase in polyunsaturated fatty acids (PUFA) proportion in the total fatty acids.

In search of better snacks: ohmic-heating nixtamalized flour and amaranth addition increase the nutraceutical and nutritional potential of vegetable-enriched tortilla chips

BACKGROUND

Nixtamalized flour snacks such as tortilla chips are widely consumed across the world, but they are nutritionally poor and contribute to obesity and other non-communicable diseases. The production of healthy versions of such snacks, by incorporating vegetables and improving the quality of the flours used in their formulation, could help address these nutritional challenges. This study compared the fortification of baked tortilla chips with vegetable leaf powders (kale and wild amaranth at 0%, 4%, 8%, and 16% w/w) and using two types of nixtamalized flour: traditional (TNF) and with ohmic heating (OHF).

RESULTS

Overall, the use of OHF increased 1.88 times the fibre in enriched and non-enriched snacks with respect to TNF, but the latter had 1.85 times more protein. Addition of 16% of vegetable powders increased protein (kale = 1.4-fold; amaranth = 1.3-fold) and dietary fibre (kale = 1.52-fold; amaranth = 1.7-fold). Amaranth enrichment improved total phenolic content (TPC) and total flavonoid content (TFC) of chips at least 1.2 and 1.63 times, respectively. OHF chips also had higher bound TPC than TNF ones, regardless of vegetable addition. Combinations of OHF with 16% amaranth produced chips 1.74-fold higher in antioxidant capacity than non-enriched ones, due to increased content of phenolics such as ferulic acid.

CONCLUSION

This work showed that tortilla chips made using nixtamalized flour produced with assisted ohmic heating, alone or in combination with wild amaranth leaf powder, could be used in the production of healthy maize snacks to enhance their prospective antioxidant activity and nutritional value. © 2023 Society of Chemical Industry.

The Effect of Fresh Kale (Brassica oleracea var. sabellica) Addition and Processing Conditions on Selected Biological, Physical, and Chemical Properties of Extruded Snack Pellets

The purpose of this study was to determine the effect of the addition of fresh kale and processing conditions on extruded pellet antioxidant activity and selected physicochemical properties. The results of the applied DPPH, FRAP, and TPC methods indicated that, for both 60 and 100 rpm screw speeds, snack pellet antioxidant activity and phenolic content were strongly linked to the fresh kale content, and these properties increased with the addition of this plant. The amount of fresh kale and the applied processing variables (extruder screw speed and the moisture content of the raw material blends) were also found to significantly affect the water absorption index, water solubility index, fat absorption index, fatty acid profile, and basic chemical composition of the obtained extrudates. The sample with the highest phenolic content (72.8 μg GAE/g d.w.), the most advantageous chemical composition (protein, ash, fat, carbohydrates, and fiber content), and high antioxidant properties was produced at a fresh kale content of 30%, a 36% moisture content, and a 100 rpm screw speed. The following phenolic acids were identified in this sample: protocatechuic, 4-OH-benzoic, vanillic, syringic, salicylic, caffeic, coumaric, ferulic, and sinapic. Sinapic acid was the prevailing phenolic acid.

Effect of the Production Parameters and In Vitro Digestion on the Content of Polyphenolic Compounds, Phenolic Acids, and Antiradical Properties of Innovative Snacks Enriched with Wild Garlic (Allium ursinum L.) Leaves

A new type of corn snack has been created containing additions of wild garlic (Allium ursinum L.). This medicinal and dietary plant has a long tradition of use in folk medicine. However, studies on wild garlic composition and activity are fairly recent and scarce. This research aimed to investigate the influence of the screw speed and A. ursinum amounts on the antiradical properties as well as the content of polyphenolic compounds and individual phenolic acids of innovative snacks enriched with wild garlic leaves. The highest radical scavenging activity and content of polyphenols and phenolic acids were found in the snacks enriched with 4% wild garlic produced using screw speed 120 rpm. The obtained findings demonstrated that snacks enriched with wild garlic are a rich source of polyphenolic compounds. Since the concentration of such compounds is affected by many factors, e.g., plant material, presence of other compounds, and digestion, the second aim of this study was to determine radical scavenging activity, the content of polyphenols, and individual phenolic acids of snacks after in vitro simulated gastrointestinal digestion. Using an in vitro two-stage model, authors noted a significant difference between the concentration of polyphenolic compounds and the polyphenol content of the plant material before digestion.

Preliminary studies on the effect of simulated digestion on the antioxidant activity of monoterpenes

One of several possible ways of predicting substance bioactivity under in vivo conditions is through simulated studies based on conditions comparable to those within the organism. Having regards to pH and digestive enzymes, such an approach is through simulated digestion. Simulated studies allow gaining an understanding of physiological conditions and a prediction of compound behavior. The presented studies are based on simulated digestion (SD) to which selected monoterpenes (γ-terpinene, α-terpinene, α-phellandrene, carvone, menthone, isopulegol, α-pinene, β-pinene, terpinene-4-ol, linalool, eucalyptol, p-cymene, citral, citronellal) have been subjected. The procedure included changes pH (2.0 and 8.5) and digestive enzymes (pepsine in gastric stage and pancreatin in duodenal stage) to better understand what goes on within the gastro-intestinal tract. The changes were observed for gastric and duodenal stages, as well as for two phases: oil and water. Obtained results revealed both positive and negative influence of gastrointestinal conditions on monoterpenes antioxidant activity. However, positive impact prevailed (γ-terpinene, citral, eucalyptol, isopulegol, α-pinene). The differentiation in activity can be explained by solubility in oil/water phases and the biotransformation of studied compounds.

Changes in Phenolics during Cooking Extrusion: A Review

In this paper, significant attention is paid to the retention of phenolics in extrudates and their health effects. Due to the large number of recent articles devoted to total phenolic content (TPC) of input mixtures and extrudates, the technological changes are only presented for basic raw materials and the originating extrudates, and only the composites identified has having the highest amounts of TPC are referred to. The paper is also devoted to the changes in individual phenolics during extrusion (phenolic acids, flavonoids, flavonols, proanthocyanidins, flavanones, flavones, isoflavons, and 3-deoxyanthocyanidins). These changes are related to the choice or raw materials, the configuration of the extruder, and the setting the technological parameters. The results found in this study, presented in the form of tables, also indicate whether a single-screw or twin-screw extruder was used for the experiments. To design an extrusion process, other physico-chemical changes in the input material must also be taken into account, such as gelatinization of starch; denaturation of protein and formation of starch, lipids, and protein complexes; formation of soluble dietary fiber; destruction of antinutritional factors and contaminating microorganisms; and lipid oxidation reduction. The chemical changes also include starch depolymerization, the Maillard reaction, and decomposition of vitamins.

trans-Cinnamic acid, but not p-coumaric acid or methyl cinnamate, induces fibroblast migration through PKA- and p38-MAPK signalling pathways

AIM

Hydroxycinnamic acids their derivatives have various pharmacological properties. The hydroxycinnamic acid derivatives, methyl cinnamate, trans-cinnamic, and p-coumaric acids have been the object of study in the treatment of skin wounds. However, it is unclear whether these derivatives exert a direct beneficial effect on fibroblast function. In this study, we evaluated the effects of methyl cinnamate, trans-cinnamic, and p-coumaric acids on fibroblast migration in vitro.

MATERIALS AND METHODS

NIH 3T3 and L929 fibroblast cell lines were exposed to each drug at several concentrations and the effect on cell viability, cell cycle, and extracellular matrix production were assessed by MTT assay, flow cytometry, and immunofluorescence staining, respectively. The effect on cell migration was examined using scratch assay.

RESULTS

The results showed that hydroxycinnamic acid derivatives not affect cell viability, but increase fibroblast migration in the in vitro scratch-wound healing assay. They also induced an increase in S and G2/M phases accompanied by a decrease in the G0/G1 phase of the cell cycle. The cell proliferation inhibitor mitomycin C abolished the effect induced by p-coumaric acid and methyl cinnamate, indicating that only the trans-cinnamic acid stimulated migration. A transwell migration assay confirmed that trans-cinnamic acid-treated fibroblasts exhibited increased migration compared with untreated cells. trans-Cinnamic acid-induced fibroblast migration was decreased by PKA inhibitor and p38-MAPK inhibitor but not by JNK inhibitor. Additionally, trans-cinnamic acid-treated fibroblasts showed an increase in the production of laminin and collagen type I.

CONCLUSION

Our study showed that trans-cinnamic acid improves fibroblast migration and modulates extracellular matrix synthesis, indicating its potential for accelerating the healing process.

The Epigenetic Link between Polyphenols, Aging and Age-Related Diseases

Aging is a complex process mainly categorized by a decline in tissue, cells and organ function and an increased risk of mortality. Recent studies have provided evidence that suggests a strong association between epigenetic mechanisms throughout an organism’s lifespan and age-related disease progression. Epigenetics is considered an evolving field and regulates the genetic code at several levels. Among these are DNA changes, which include modifications to DNA methylation state, histone changes, which include modifications of methylation, acetylation, ubiquitination and phosphorylation of histones, and non-coding RNA changes. As a result, these epigenetic modifications are vital targets for potential therapeutic interventions against age-related deterioration and disease progression. Dietary polyphenols play a key role in modulating these modifications thereby delaying aging and extending longevity. In this review, we summarize recent advancements linking epigenetics, polyphenols and aging as well as critical findings related to the various dietary polyphenols in different fruits and vegetables. In addition, we cover studies that relate polyphenols and their epigenetic effects to various aging-related diseases such as cardiovascular diseases, neurodegenerative diseases, autoimmune disorders, diabetes, osteoporosis and cancer.

Phenolic acids from vegetables: A review on processing stability and health benefits

Phenolic acids are the most prominent group of bioactive compounds present in various plant sources. Hydroxybenzoic acids and hydroxycinnamic acids, the aromatic secondary metabolites imparting typical organoleptic characteristics to food are the major phenolic acids, and they are linked to several health benefits. Fruit and beverage crops being the richer sources of phenolic acids have been studied in depth, but phenolic acids from vegetables are largely overlooked. Though lesser in quantity in many vegetables, there is a need to explore the health benefits of the phenolic acids present in them. In this review, the importance of vegetables as a significant source of phenolic acids is emphasized. Vegetables being easily accessible throughout the year and consumed in larger quantities compared to fruits in our daily diet will probably contribute to significant health benefits. Since vegetables are often processed before consumption, the changes in phenolic acids as influenced by processing methods are highlighted. Best processing methods, pre-treatments and storage conditions for higher retention of phenolic acids have been highlighted to minimize their losses. The phenolic acids in vegetables and their health benefits have been cluster mapped, which may facilitate further research for nutraceutical development for specific health concerns. The processing stability of phenolic acids coupled with higher consumption indicates that they may be a potential source of phenolic acids in the diet. It is expected that the popularization of vegetables as a source of phenolic acids in daily diet will help in ameliorating the adverse effect of some of the lifestyle diseases.

Side Streams of Broccoli Leaves: A Climate Smart and Healthy Food Ingredient

Human consumption of fruits and vegetables are generally below recommended levels. Waste from the production, e.g., of un-used parts such as broccoli leaves and stem when producing broccoli florets for food, is a sustainability issue. In this study, broccoli leaves were analyzed for the content of various dietary fibre and phenolics, applying the Uppsala method and HPLC analyses, respectively. The results showed that broccoli leaves had comparable levels of dietary fibre (26%-32% of dry weight (DW)) and phenolic compounds (6.3-15.2 mg/g DW) to many other food and vegetables considered valuable in the human diet from a health perspective. A significant positive correlation was found among soluble dietary fibre and phenolic acids indicating possible bindings between these components. Seasonal variations affected mainly the content of conjugated phenolics, and the content of insoluble dietary fibre. This study verified the importance of the use of broccoli production side streams (leaves) as they may contribute with health promoting components to the human diet and also socio-economic and environmental benefits to the bioeconomic development in the society.

Transcriptome sequencing and identification of key callus browning-related genes from petiole callus of tree peony (Paeonia suffruticosa cv. Kao) cultured on media with three browning inhibitors

Tree peony (Paeonia suffruticosa Andrews) has ornamental, oil, and medicinal values, and demand in the markets for uniform tree peony seedlings is increasing. Micropropagation could quickly propagate uniform seedlings. However, the heavy browning phenomenon hinders large-scale development of uniform tree peony seedlings. In this paper, we measured the total phenolic compounds content, and sequenced the transcriptomes of tree peony 'Kao' petiole calluses cultured on media with three browning antagonist treatments and fresh petioles to identify the key genes involved in callus browning. Polyvinylpyrrolidone (PVP) treatment can reduce production of phenolic compounds and promote callus regeneration. A total of 218,957 unigenes were obtained from fresh petiole and three kinds of browning petiole calluses by transcriptome sequencing. The average sequence length of unigenes was 446 bp with an N50 of 493 bp. Functional annotation analysis revealed that 43,428, 45,357, 31,194, 30,019, and 21,357 unigenes were annotated using the NCBI-NR database, Swiss-Prot, KOG, GO, and KEGG, respectively. In total, 33 differentially expressed genes (DEGs) were identified as potentially associated with callus browning. Among these DEGs, 12 genes were predicted to participate in phenolic compounds biosynthesis, three genes were predicted to be involved in phenolic compounds oxidation, and six genes were predicted to participate in callus regeneration. Moreover, six transcription factors were observed to be differentially expressed in the fresh petiole and three treated petioles in tree peony. This study comprehensively identifies browning-related gene resources and will possibly help in deciphering the molecular mechanisms of callus browning of tree peony in the future.

Glycerol as Alternative Co-Solvent for Water Extraction of Polyphenols from Carménère Pomace: Hot Pressurized Liquid Extraction and Computational Chemistry Calculations

Glycerol is a co-solvent for water extraction that has been shown to be highly effective for obtaining polyphenol extracts under atmospheric conditions. However, its efficacy under subcritical conditions has not yet been studied. We assessed different water-glycerol mixtures (15%, 32.5%, and 50%) in a hot pressurized liquid extraction system (HPLE: 10 MPa) at 90 °C, 120 °C, and 150 °C to obtain extracts of low molecular weight polyphenols from Carménère grape pomace. Under the same extraction conditions, glycerol as a co-solvent achieved significantly higher yields in polyphenols than ethanol. Optimal extraction conditions were 150 °C, with 32.5% glycerol for flavonols and 50% for flavanols, stilbenes, and phenolic acids. Considering gallic acid as a model molecule, computational chemistry calculations were applied to explain some unusual extraction outcomes. Furthermore, glycerol, methanol, ethanol, and ethylene glycol were studied to establish an incipient structure-property relationship. The high extraction yields of gallic acid obtained with water and glycerol solvent mixtures can be explained not only by the additional hydrogen bonds between glycerol and gallic acid as compared with the other alcohols, but also because the third hydroxyl group allows the formation of a three-centered hydrogen bond, which intensifies the strongest glycerol and gallic acid hydrogen bond. The above occurs both in neutral and deprotonated gallic acid. Consequently, glycerol confers to the extraction solvent a higher solvation energy of polyphenols than ethanol.

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.