1,721,110 research outputs found
Influence of some packaging materials and of natural tocopherols on the sensory properties of breakfast cereals
No full textThe combined effect of natural antioxidants and packaging materials on the quality decay of breakfast cereals during storage was evaluated. Corn flakes were produced on industrial scale, using different packages and adding natural tocopherols to the ingredients, and stored for 1 year. The samples were then submitted to sensory analysis and HS-solid phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS) analysis. The packaging had a significant influence on the sensory profile of the aged product: metallized polypropylene gave the highest levels of oxidation compounds and sensory defects. The sensory profile was improved using polypropylene and especially high-density polyethylene. Natural tocopherols reduced the sensory decay of the flakes and the oxidative evolution of the volatile profile. They gave the most remarkable improvement in polypropylene (either metallized or not) packs. Polypropylene showed a barrier effect on the scalping of volatiles outside of the pack. This led to higher levels of oxidation volatiles and faster rates of the further oxidative processes involving the volatiles. © The Author(s) 2013
Faba greens, globe Artichoke’s offshoots, crenate broomrape and summer squash greens: Unconventional vegetables of Puglia (Southern Italy) with good quality traits
No full textGlobe artichoke (Cynara cardunculus L. subsp. [L.] scolymus Hayek), summer squash (Cucurbita pepo L.) and faba bean (Vicia faba L.) are widely cultivated for their immature inflorescences, fruits and seeds, respectively. Nevertheless, in some areas of Puglia (Southern Italy), other organs of these species are traditionally used as vegetables, instead of being considered as by-products. Offshoots (so-called cardoni or carducci) of globe artichoke, produced during the vegetative growing cycle and removed by common cultural procedures, are used like to the cultivated cardoons (C. cardunculus L. var. altilis DC). The stems, petioles, flowers and smaller leaves of summer squash are used as greens (so-called cime di zucchini), like other leafy vegetables such as chicory (Cichorium intybus L.) and Swiss chard (Beta vulgaris L.). Also the plant apex of faba bean, about 5-10 cm long, obtained from the green pruning, are used as greens (so-called cime di fava) like spinach leaves. Moreover, crenate broomrape (Orobanche crenata Forssk.), a root parasite plant that produces devastating effects on many crops (mostly legumes), is used like asparagus (Asparagus officinalis L.) to prepare several traditional dishes. In this study ethnobotanical surveys and quality assessment of these unconventional vegetables were performed. For their content of fiber, offshoots of globe artichokes can be considered a useful food to bowel. Summer squash greens could be recommended as a vegetable to use especially in the case of hypoglycemic diets considering both content and composition of their carbohydrates. For their low content of nitrate, faba greens could be recommended as a substitute of nitrate-rich leafy vegetables. Crenate broomrape shows a high antioxidant activity and may be considered as a very nutritious agri-food product. Overall, the results of the present study indicate that offshoots of globe artichoke, summer squash greens, faba greens and crenate broomrape have good potential as novel foods, being nutritious and refined products. Their exploitation aiming to the obtainment of labeled and/or new potential ready-to-eat retail products could satisfy the demand for local functional foods
An effort to improve the shelf life of breakfast cereals using natural mixed tocopherols
No full textAn experimental investigation was carried out with the aim of appraising the effects of natural tocopherols on lipid oxidation in extruded breakfast cereals. Corn flakes produced on an industrial scale, with and without added tocopherols and stored in commercial packing under shelf conditions, were compared using sensory evaluation and analyses of volatile compounds and triacylglycerol polymerization products. The sensory evaluation showed the effectiveness of tocopherols in limiting the development of off-flavour during storage. The analysis of the volatile compounds, focused on the secondary products of the lipid oxidation, showed that the antioxidant activity of tocopherols limited the evolution of the headspace towards a more intense oxidation, notably the further oxidation of hexanal into hexanoic acid (that reached 32% and 15% in the flakes, respectively, without and with added tocopherols, after 360 days). The percentage of hexanoic acid in the headspace positively correlated with almost all the descriptors of the defect considered for the sensory evaluation. The analysis of the triacylglycerol polymerization products confirmed the inhibiting action of tocopherols on lipid oxidative degradation. © 2007 Elsevier Ltd. All rights reserved
An “Omics” Approach for Lipid Oxidation in Foods: The Case of Free Fatty Acids in Bulk Purified Olive Oil
No full textMonitoring or preventing oxidation processes in foods, particularly heterogeneous systems or highly oxidizable lipids, has become a primary issue. Traditional approaches often fail in pursuing this aim. At the same time, the prediction in laboratory of the efficacy of antioxidant molecules and technologies often fails when challenging reality. A change in the traditional paradigm used to conceive oxidation processes and their monitoring could be a key. In the present work, an “omics” approach is suggested for the evaluation of oxidation in food lipids and of the role played by minor compounds. This holistic and comprehensive, hypothesis-generating approach is applied to a typical research case: highly-purified olive oil added with increasing amounts of purified free fatty acids (FFA). A comprehensive profile (“oxidome”) of oxidation products is outlined during the accelerated oxidation. The pathways considered are FFA and triacyglycerol oxidation, triacyglycerol polymerization, volatile compounds formation as well as their further oxidation. FFA affectes the overall balance of the oxidation pathways and consequently causes a drift in the evolution of the pattern of oxidation products. The balance between accelerating activity of FFA toward triacylglycerol oxidation and their high susceptibility to undergo oxidation turnes out to be dose-dependent and time-related, and shiftes the resulting oxidation profile of the oil. The omics approach to oxidation products profiling provides new insight into oxidation processes. “Oxidomics” could be helpful to deepen the insight into unresolved issues of oxidation, going beyond the usual single- or few-marker approach. Practical Applications: This research suggests a new paradigm for approaching food lipid oxidation. Unresolved practical issues regarding food spoilage and shelf-life, waste reduction, keeping of healthy properties are increasing along the increasing formulation of complex and dispersed systems, use of healthy highly unsaturated fatty acids and bioactive antioxidants, attention paid by consumers and industries to nutritional, sensory, health properties of foods. The new paradigm suggests going beyond the usually adopted single- or few-marker approach and to consider the pattern of oxidation reactions and products as a whole, in order to better describe and predict its changes and the effects of external factors as well as added molecules. “Oxidomics” is a new paradigm for lipid oxidation, with a holistic approach to the system and evaluating a pattern of oxidation products and its changes
Effect of added natural tocopherols on the sensory characteristics of corn flakes during storage
No full textIn order to investigate on the appearance and evolution of sensory defects due to lipid oxidation during the storage of breakfast cereals, and on the possibility to slow down such phenomena, corn flakes added with natural tocopherols have been compared with a control without added antioxidants. The sensory evaluation and the statistic analysis of the data (ANOVA and PCA) have underlined that during the storage of the cereals sensory defects appeared, both nasal and retronasal, due to the lipid oxidation, defined as stale, rancid and pungent. The flakes without added tocopherols presented significantly more intense off-flavors than those perceived in the flakes with added antioxidants, which showed sensory profiles comparable to those shown by control in preceding storage phases
Production trials to improve the nutritional quality of biscuits and to enrich them with natural anthocyanins
No full textThe aim of the work was to improve the nutritional quality of biscuits and to enrich them with anthocyanins. The steps were (i) evaluation of various raw materials as sources of anthocyanins and optimization of anthocyanin extraction procedure; (ii) conduction of six biscuit-production trials by using anthocyanins extracted from the selected source, at different enrichment levels and with progressively less fat and sugar; and (iii) conduction of a paired-preference test to compare the best anthocyanin-enriched biscuits to control plain biscuits. Grape marc extract was selected for biscuit making. Also, the use of durum wheat semolina and extra virgin olive oil was proposed. A fat level as low as 100 g/kg was achieved, with a notable decrease of saturated fatty acids. Total anthocyanins accounted for 10361073 g/kg. The color of biscuits was characterized by more intense redness and minor lightness compared to the control, and acceptability was adequate, as assessed by 103 consumers
Packaging and antioxidants: Two synergic approaches to improve the shelf-life of breakfast cereals
No full textIn previous investigations natural antioxidants were proven to be effective in slowing down oxidative processes in breakfast cereals and limiting, as a consequence, the onset of off-flavours during storage. The list of the ingredients, on the other hand, is one of the aspects that can be taken in consideration in order to preserve the product properties during its shelf-life: the choice of a suitable packaging, in fact, should be considered with the same attention, since the extreme market segmentation lead to many different packaging solutions. The present work was aimed to investigate on the behaviour of natural antioxidants in breakfast cereals stored for 180 days in different commercial packages: a double-layer coextruded polypropylene bag and a high density polyethylene bag combined with a cardboard box. Qualitative descriptive sensory analysis was performed on these products. The results obtained showed interesting interactions between antioxidant and packaging: the polyethylene packaging sensibly improved the sensory properties of the product, acting in synergy with the employed antioxidants
Vacuum-packaging of ripened sausages: Assessment of the sensorial and chemical characteristics and of the lipid fraction degradation
No full textIn order to determine the influence of vacuum-packaging on the sensorial characteristics and on the degradation of the sausages’ lipid fraction, vacuum-packaged ripened sausages were stored for forty days and compared with the same sausages before the packaging at the end of their ripening period. As regards the sensory properties, vacuum-packaged sausages showed, after the storage period, significantly lower mean scores of red intensity (p < 0.01), global flavour (p < 0.05) and ripened flavour (p < 0.001), thus indicating a minor overall appreciation by the panellists, while no significant differences were found in relation to the descriptors that are considered defects for this category of products. Moreover, the obtained data showed a significant increase of the oxidative and hydrolytic degradation during the storage in vacuum packaging
Preliminary study on the pro-oxidant activity of polar triglyceride oligopolymers in edible oils
No full textThe pro-oxidant activity played by oxidised lipids in edible oils has already been reported in literature. However, it is still unknown whether all the classes of compounds due to oxidation and polimerisation, present in the oxidised fraction of a fat, have an equivalent pro-oxidant activity or if this activity is mainly performed by some of them. The aim of this research was that of evaluating the pro-oxidant effect of one of these classes, always present in refined oils, represented by the oligopolymers of oxidised triglycerides. Silica gel column chromatography was used to obtain the polar compounds (PC) from a thermo-oxidised oil, while preparative gel permeation chromatography of PC was carried out for separating and collecting the oligopolymers of oxidised triglycerides. A purified oil (not containing products of oxidation and hydrolytic degradation as well as free of pigments and substances having antioxidant activity) was prepared in laboratory with the aim to evaluate the pro-oxidant effect without interferences. The addition to the purified oil of variable percentages of polar triglyceride oligopolymers, in a range comprised between 0.25 and 1.0 %, fully evidenced the pro-oxidant activity of this class of compounds
Everything Should Be as Simple as It Can Be. But Not Simpler. Does Food Lipid Oxidation Require an Omics Approach?
No full textLipid oxidation remains a major challenge for the food industry and for researchers. Current methods and knowledge often fail to adequately represent what is consistently observed in real systems. Practical experience strongly suggests the need for new paradigms to fully comprehend lipid oxidation. This viewpoint article aims to mention some critical aspects of current approaches in evaluating lipid oxidation in food systems, and to search for new epistemological and therefore experimental approaches by adopting an interdisciplinary perspective. Herein, suggestions are formulated for a holistic perspective by combining elements ranging from philology to community ecology and systems biology. Lipids undergoing oxidation are compared to ecological communities and living systems, to be considered as a whole, whose patterns change with space and time. As omics is an inductive, hypothesis-generating, circular approach, involving multiparametric analysis, data integration/fusion, and multivariate statistical analysis (both supervised and unsupervised), it could thus provide a useful contribution to better understanding of oxidation and antioxidation processes, enabling laboratory results to be matched with what is observed in real complex foods. Practical applications: There is still a large gap between the wealth of natural compounds with antioxidant activity and the availability of natural products able to prevent rancidity in food products. Moreover, healthy, highly unsaturated fatty acids still require appropriate methods to monitor oxidative spoilage. Dispersed systems and multidomain foods pose new daily challenges regarding oxidation assessment and control. These are critical issues in the food industry, indicating the need to identify a new approach to lipid oxidation in food systems, and this viewpoint article is a contribution to the ongoing debate. A new epistemological paradigm for lipid oxidation in food systems. It consists of the reiteration of hypothesis-generating studies (oxidomics), requiring multiparametric, comprehensive profiling of the oxidation patterns (oxidome) and their changes. The outcome is a progressive improvement in the knowledge of complex systems and the selection of appropriate predisposition, prognostic and diagnostic marker patterns for the oxidation process
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