A comparative study between natural and synthetic antioxidants: Evaluation of their performance after incorporation into biscuits

Currently, the food industry is focused in replacing the use of synthetic by natural antioxidants. The present study focused on the use of fennel and chamomile extracts, rich in phenolic compounds, as natural antioxidants in biscuits and compared their performance with a synthetic antioxidant widely used, the butylated hydroxyl anisole (BHA). The complete nutritional profile, free sugars, fatty acids and antioxidant activity were determined immediately after baking and also after 15, 30, 45 and 60 days of storage. The results showed that the incorporation of natural and synthetic additives did not cause significant changes in colour or in nutritional value of biscuits when compared with control samples. Both natural and synthetic additives conferred similar antioxidant activity to the biscuits. Therefore, natural additives are a more convenient solution for consumers who prefer foods “free” from synthetic additives. Additionally, natural additives were obtained by aqueous extraction, an environment friendly and safe process.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER for CIMO (UID/AGR/00690/2013) and LSRE (Project UID/EQU/50020/2013) financial support, and C. Caleja (SFRH/BD/93007/ 2013) and L. Barros (SFRH/BPD/ 107855/2015) grants. The authors also thank Ms Clarinda Paixão, from Américo Duarte Paixão Lda, Portugal, for providing the plant samples.info:eu-repo/semantics/publishedVersio

The role of chamomile phenolic compounds in the development of dairy functional foods

There is a growing interest for healthier foods either by consumers or by industrial sectors [1]. Bioactive phytochemicals, such as phenolic compounds (PC), have been used in the preparation of nutraceuticals and functional foods [2]. In the present work, the antioxidant and antimicrobial properties of plant extracts rich in PC were evaluated. Matricaria recutita L. (chamomile) extracts were prepared following a decoction procedure and displayed 2, 2-diphenyl-l-picrylhydrazyl scavenging activity (EC5o = 335 ± 3 Mg/mL), reducing power (238 ± 38 pg/mL), p-carotene bleaching inhibition (297 ± 27 pg/mL) and lipid peroxidation inhibition (72 ± 2 pg/mL). The bactéria Staphylococcus aureus (MIC=35 pg/mL), Baaï/us cereus (MIC=100 pg/mL) and Salmonella typhimurium (MIC=100 MS/mL), as also the fungi Penicillium funiculosum (MIC=200 MS/mL), Aspergillus versicolor (MIC=400 pg/mL) and Trichoderma viride (MIC=400 pg/mL), were susceptible to the action of chamomile phenolic extracts. Their chemical characterization, performed by HPLC-DAD-ESI/MS, revealed the presence of nine flavonoids (mainly luteolin-0-glucuronide) and ten phenolic acids (mainly di-caffeoyl-2, 7-anhydro- 3-deoxy-2-octulopyranosonic acid). Due to the observed bioactive properties, chamomile phenolic extracts were used to functionalize yogurts. This functionalization did not cause significant changes in the yoghurt pH and nutritional value, but improved antioxidant properties when compared with control samples. The obtained results support the use of PC extracts in the development of novel dairy foods.The authors are grateful to e Foundation for Science and Technology (FCT, Portugal) and FEDER under Pmgramme PT2020 for financiai support to CIMO (UID/AGR/0069/2013), REQUIMTE (UID/QUI/50006/2013 - POCI/01/0145/ FERDER/007265), C. Caleja (SFRH/BD/93007/2013) and L Banos (SFRH/BPD/107855/2015) grants.N/

Nova formulação de iogurtes com extratos aquosos de funcho e camomila na substituição de aditivos químicos

Existe por parte dos consumidores uma tendência crescente na escolha de alimentos designados por mais saudáveis em que a presença em aditivos sintéticos é reduzida ou até mesmo ausente. Para melhorar a aparência e/ou propriedades dos alimentos a indústria recorre ao uso de aditivos sintéticos [1], no entanto, alguns autores têm apresentado alguma relação entre o consumo excessivo de alguns desses aditivos com efeitos adversos para a saúde do consumidor [2]. Para contornar esta problemática e ir ao encontro das expectativas dos consumidores, têm sido considerados os extratos naturais obtidos a partir de plantas como excelentes ingredientes naturais para a indústria alimentar como alternativas aos aditivos sintéticos [3]. Este trabalho teve como objetivo comparar os efeitos de antioxidantes naturais (extratos aquosos de Foeniculum vulgare Mill., funcho, e Matricaria recutita L., camomila, obtidos por decocção) com um aditivo sintético (sorbato de potássio, E202) utilizado em iogurtes. Neste trabalho, as amostras de Foeniculum vulgare Mill. (funcho) e Matricaria recutita L. (camomila) foram submetidas a uma extração por decocção. A sua caracterização química foi feita por HPLC-DAD-ESI/MS. As propriedades antioxidantes foram avaliadas através de diferentes ensaios in vitro (efeito captador de radicais livres, poder redutor e inibição da peroxidação lipídica), tal como as propriedades antimicrobianas (contra bactérias e fungos). A incorporação dos extratos foi feita em iogurtes e desta forma, foram preparados quatro grupos de amostras: iogurtes controlo (sem adição de qualquer aditivo), iogurtes com decocção de funcho, iogurtes com decocção de camomila e iogurtes com E202. As amostras foram avaliadas quanto à cor, pH e ao seu valor nutricional e potencial antioxidante. O estudo foi feito no tempo zero e após sete e catorze dias de armazenamento a 4ºC. Tal como podemos observar na Figura 1, a incorporação dos aditivos quer naturais quer sintéticos, não provocou alteração no aspeto visual quando comparado com a amostra controlo sem aditivos (A). Os resultados demonstram ainda que a introdução dos aditivos não provocou alterações significativas no pH e no valor nutricional dos iogurtes quando comparados com o controlo (Tabela 1). No entanto, esta incorporação conferiu propriedades antioxidantes aos iogurtes principalmente, pela adição do extrato de camomila (Figura 2). Estes resultados permitem-nos concluir que os extratos aquosos de funcho e camomila ricos em compostos fenólicos [4,5] podem representar uma alternativa aos conservantes sintéticos melhorando desta forma as propriedades funcionais dos iogurtes sem, no entanto, provocar alterações no perfil nutricional dos mesmos

Fortification of yogurts with different antioxidant preservatives: a comparative study between natural and synthetic additives

Consumers demand more and more so-called "natural" products and, therefore, the aim of this work was to compare the effects of natural versus synthetic antioxidant preservatives in yogurts. Matricaria recutita L. (chamomile) and Foeniculum vulgare Mill. (fennel) decoctions were tested as natural additives, while potassium sorbate (E202) was used as a synthetic additive. The fortification of yogurts with natural and synthetic antioxidants did not cause significant changes in the yoghurt pH and nutritional value, in comparison with control samples (yogurt without any additive). However, the fortified yogurts showed higher antioxidant activity, mainly the yogurts with natural additives (and among these, the ones with chamomile decoction). Overall, it can be concluded that plant decoctions can be used to develop novel yogurts, by replacing synthetic preservatives and improving the antioxidant properties of the final product, without changing the nutritional profile.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for C. Caleja (SFRH/BD/93007/ 2013) and L. Barros (SFRH/BPD/107855/2015) grants. The authors also thank Ms Clarinda Paixão, from Américo Duarte Paixão Lda, Portugal, for providing the plant samples

Variation in organic acids content in Tuberaria lignosa extracts induced by ionizing radiation and extraction procedures

Organic acids are important nutritional phytochemicals and some of them have biological activity, and thus a significant impact on human health. Additionally, they also act as precursors of phenolics and flavour compounds [1]. Tuberaria lignosa (Sweet) Samp. is one of the most quoted medicinal plants in several regions of the Iberian Peninsula, used to treat various diseases and ailments [2]. It was previously highlighted by our research group as a source of bioactive compounds [3], but its content in organic acids was still unknown. As biomolecules can be degraded by improper processing treatments or even extraction methods [3], this work aims to find variations in organic acids content in T. lignosa extracts induced by both ionizing radiation and extraction procedures. Dried T. lignosa samples, obtained in a Northeastern Portuguese region, were exposed to 0 (control), 1, 5 and 10 kGy of γ-rays in a 60Co experimental chamber, and then extracted by water infusion and decoction. The organic acids were analysed by ultrafast liquid chromatography coupled to a photodiode array detector (UFLC-PDA). Oxalic, quinic, malic, shikimic and succinic acids were quantified in all the extracts, being shikimic acid the most abundant. In infusion preparations, irradiated samples exhibited lower contents than the non-irradiated control (except for oxalic acid in the sample irradiated with 10 kGy). On the other hand, in decoctions, only oxalic acid was negatively affected by the irradiation treatment; while the other organic acids values remained unchanged or were improved. But, despite the negative effect of irradiation on samples extracted by infusion, the total organic acids content remained higher in these samples than in those extracted by decoction. Thus, infusion is preferable over decoction to extract organic acids from irradiated T. lignosa.FCT for financial support to CIMO (PEst-OE/AGR/UI0690/2011), J. Pinela grant (SFRH/BD/92994/2013) and L. Barros contrac

Using gamma irradiation to attenuate the effects caused by drying or freezing in Macrolepiota procera organic acids and phenolic compounds

Macrolepiota procera (Scop.) Singer, commonly parasol mushroom, is an appreciated wild edible species. Due to its very perishable nature, M. procera must be processed to extend its shelf life. The chemical changes caused by common processing types should be avoided to maintain the wholesomeness of organoleptic features. Irradiation might be used as a preservation methodology due to its safety, cost effectiveness and ability to ensure hygienic and sensory quality. Furthermore, when combined with other preservation technologies, irradiation exhibits an attenuating effect over the chemical changes caused by some of those treatments per se. Herein, the effects of irradiation of M. procera processed samples (frozen, dried and fresh) were evaluated considering changes in organic acid and phenolic compound profiles. Detected contents of phenolic were much lower than those of organic acids. Differences caused by processing type, specifically the lower levels of total organic acids and phenolic acids in dried and frozen samples, were larger than those observed for stronger irradiation doses, which did not cause remarkable changes, except for a slightly lower content of phenolic acids in non-irradiated samples. This larger effect was statistically confirmed in the performed linear discriminant analysis. Besides its slighter influence, irradiation showed potential usefulness to be used as complementary preservation technology since it attenuated the lowering effects of dehydration and freeze treatment over specific organic acid contents.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support of research centres CIMO (PEst-OE/AGR/UI0690/2011) and REQUIMTE (PEst-C/EQB/LA0006/2011). Â. Fernandes, A.L. Antonio and J.C.M. Barreira thank FCT, POPH-QREN and FSE for their grants (SFRH/BD/76019/2011, SFRH/PROTEC/67398/2010 and SFRH/BPD/72802/2010, respectively). L. Barros thanks FCT for her researcher contract under “Programa Compromisso com Ciência-2008

Quality control of gamma irradiated dwarf mallow (Malva neglecta Wallr.) based on color, organic acids, total phenolics and antioxidant parameters

This study addresses the effects of gamma irradiation (1, 5 and 8 kGy) on color, organic acids, total phenolics, total flavonoids, and antioxidant activity of dwarf mallow (Malva neglecta Wallr.). Organic acids were analyzed by ultra fast liquid chromatography (UFLC) coupled to a photodiode array (PDA) detector. Total phenolics and flavonoids were measured by the Folin-Ciocalteu and aluminium chloride colorimetric methods, respectively. The antioxidant activity was evaluated based on the DPPH(•) scavenging activity, reducing power, β-carotene bleaching inhibition and thiobarbituric acid reactive substances (TBARS) formation inhibition. Analyses were performed in the non-irradiated and irradiated plant material, as well as in decoctions obtained from the same samples. The total amounts of organic acids and phenolics recorded in decocted extracts were always higher than those found in the plant material or hydromethanolic extracts, respectively. The DPPH(•) scavenging activity and reducing power were also higher in decocted extracts. The assayed irradiation doses affected differently the organic acids profile. The levels of total phenolics and flavonoids were lower in the hydromethanolic extracts prepared from samples irradiated at 1 kGy (dose that induced color changes) and in decocted extracts prepared from those irradiated at 8 kGy. The last samples also showed a lower antioxidant activity. In turn, irradiation at 5 kGy favored the amounts of total phenolics and flavonoids. Overall, this study contributes to the understanding of the effects of irradiation in indicators of dwarf mallow quality, and highlighted the decoctions for its antioxidant properties.The authors are grateful to PRODER research project nº 53514, AROMAP, for financial support of the work and to the Foundation for Science and Technology (FCT, Portugal) for financial support to CIMO (PEst-OE/AGR/UI0690/2014), REQUIMTE (UID/QUI/50006/2013), C2TN (RECI/AAG-TEC/0400/2012), J. Pinela (SFRH/BD/92994/2013) and L. Barros (SFRH/BPD/107855/2015)

Effects of different processing technologies on chemical and antioxidant parameters of Macrolepiota procera wild mushroom

Mushrooms are very perishable foods, demanding for processing technologies that retain chemical and nutritional characteristics of fresh forms. In this work, the influence of freezing, drying and gamma irradiation on chemical parameters and antioxidant potential of Macrolepiota procera was assessed through one-way ANOVA complemented with principal component analysis. Proximate composition was evaluated by AOAC procedures, while fatty acids, tocopherols and free sugars were determined using chromatographic techniques. Antioxidant activity was measured using in vitro assays. M. procera samples have low energetic values, with moisture and carbohydrates as major nutrients. Linoleic, palmitic and oleic acids were the major fatty acids; δ-tocopherol was the prevalent isoform in fresh, frozen and irradiated samples, while β-tocopherol predominated in dried samples. Trehalose was the most abundant sugar in fresh and irradiated samples, whereas mannitol predominated in frozen and dried samples. Dried samples gave higher DPPH scavenging activity and β-carotene bleaching inhibition; freeze and irradiated samples showed higher reducing power and TBARS formation inhibition, respectively. Overall, freezing and drying caused significant differences in chemical parameters. On the other hand, gamma irradiation revealed the highest capacity to retain chemical profile of fresh samples, which highlights its potential to be explored and validated as an alternative conservation methodology.Foundation for Science and Technology (FCT, Portugal) for financial support of research centres CIMO (PEst-OE/AGR/UI0690/2011) and REQUIMTE (PEst-C/EQB/LA0006/2011). Â. Fernandes, L. Barros, J.C.M. Barreira and A.L. Antonio thank FCT, POPH-QREN and FSE for their grants (SFRH/BD/76019/2011, SFRH/BPD/4609/2008, SFRH/BPD/72802/2010 and SFRH/PROTEC/67398/2010, respectively)

Electron-beam irradiation as an alternative to preserve nutritional, chemical and antioxidant properties of dried plants during extended storage periods

According to current market demands, there is an increasing need for improved conservation methodologies. In addition to an extension in shelf-life, food products should preserve their compositional integrity and bioactive properties throughout storage time. Irradiation technology has been progressively considered as a feasible conservation technology. Electron-beam irradiation, in particular, might be predominantly suitable to be applied in food products with reduced thickness, such as aromatic and medicinal plants. In this study, the effects of e-beam irradiation on chemical, nutritional and antioxidants parameters of different plant species were evaluated. To assess the potential of this technology over extended periods, plant samples were stored for the first time up to a maximum of 18 months. Despite some heterogeneity among the effects produced in each plant species, electron-beam treatment attenuated the reduction of individual compounds (primarily, free sugars, organic acids, tocopherols and polyunsaturated fatty acids) verified in non-irradiated samples, showing its potential as an alternative conservation technology.The authors are grateful to the Ministry of Agriculture, Portugal, (Project PRODER/FEADER/EU no 53514, AROMAP), for financial support of the work and E. Pereira grant, and to Foundation for Science and Technology (FCT, Portugal) and FEDER for financial support to CIMO (UID/AGR/00690/2013), J.C.M. Barreira (BPD/72802/2010) and L. Barros (SFRH/BPD/107855/2015) grants. Prof. A. Chmielewski, General Director of the Institute of Nuclear Chemistry and Technology, Warsaw, Poland, for allowing e-beam irradiations. The authors are also grateful to “MaisErvas - Aromáticas e Medicinais” for providing the plant material.info:eu-repo/semantics/publishedVersio

Postharvest quality changes in fresh-cut watercress stored under conventional and inert gas-enriched modified atmosphere packaging

The effect of modified atmosphere packaging (MAP) on the postharvest quality of fresh-cut watercress (Nasturtium officinale R. Br.) stored at 4 ºC for 7 d was studied. A portion of watercress was immediately analyzed (non-stored control) and the remaining fresh material was stored packaged under atmospheres enriched with N2, Ar, air, or vacuum. The analyzed parameters included colour, total soluble solids, pH, macronutrients, the individual profiles of sugars, organic acids, tocopherols and fatty acids, and total phenolics and flavonoids. Furthermore, four in vitro assays were performed to evaluate the antioxidant activity. After assessing the effect on individual quality parameters, it was possible to conclude that air was the less efficient atmosphere in preserving quality attributes of the non-stored control samples during cold storage. In turn, Ar-enriched MAP was the most suitable choice to preserve the overall postharvest quality. The present study also highlighted the nutritional and antioxidant properties of watercress, as well as the interest of its inclusion in human diets.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to CIMO (PEst-OE/AGR/UI0690/2014), REQUIMTE (UID/QUI/50006/2013), J. Pinela (SFRH/BD/92994/2013), J.C.M. Barreira (SFRH/BPD/72802/2010) and L. Barros (“Compromisso para a Ciência 2008” contract)