Front-face fluorescence spectroscopy and chemometrics for quality control of cold-pressed rapeseed oil during storage

The aim of this study was to test the usability of fluorescence spectroscopy to evaluate the stability of cold-pressed rapeseed oil during storage. Freshly-pressed rapeseed oil was stored in colorless and green glass bottles exposed to light, and in darkness for a period of 6 months. The quality deterioration of oils was evaluated on the basis of several chemical parameters (peroxide value, acid value, K232 and K270, polar compounds, tocopherols, carotenoids, pheophytins, oxygen concentration) and fluorescence. Parallel factor analysis (PARAFAC) of oil excitation-emission matrices revealed the presence of four fluorophores that showed different evolution throughout the storage period. The fluorescence study provided direct information about tocopherol and pheophytin degradation and revealed formation of a new fluorescent product. Principal component analysis (PCA) performed on analytical and fluorescence data showed that oxidation was more advanced in samples exposed to light due to the photo-induced processes; only a very minor effect of the bottle color was observed. Multiple linear regression (MLR) and partial least squares regression (PLSR) on the PARAFAC scores revealed a quantitative relationship between fluorescence and some of the chemical parameters.Funding Agency Ministry of Science and Higher Education, Poland NN312428239 Poznan University of Economics and Businessinfo:eu-repo/semantics/publishedVersio

Faba Greens, Globe Artichoke’s Offshoots, Crenate Broomrape and Summer Squash Greens: Unconventional Vegetables of Puglia (Southern Italy) With Good Quality Traits

Globe 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

Everything Should Be as Simple as It Can Be. But Not Simpler. Does Food Lipid Oxidation Require an Omics Approach?

Lipid 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

An “Omics” Approach for Lipid Oxidation in Foods: The Case of Free Fatty Acids in Bulk Purified Olive Oil

Monitoring 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

Fat replacement in shortbread cookies using an emulsion filled gel based on inulin and extra virgin olive oil

The European Food Safety Agency recommends low intakes of saturated fatty acids. This study evaluated the replacement of 50% and 100% of butter in shortbread cookies with an emulsion filled gel (EFG) based on inulin and extra virgin olive oil (EVOO), and investigated its impact on product characteristics (volatile profile, fracture behaviour and crumb pore size, sensory properties). Cookies containing both 50% and 100% EFG had thinner pore walls than the control cookies, without EFG. The total substitution of butter with EFG gave products with higher number of small-sized pores and lower level of fracture stress, with poorer sensory properties than control cookies. The replacement of 50% of the butter fraction of shortbread with EFG based on inulin and EVOO did not substantially affect cookie microstructure, compared to control. Cookies with 50% butter replacement showed comparable fracture properties, and were well accepted by consumers, resulting a product with potentially healthier properties (19% less total fat, 39% less saturated fats) respect to control cooki

Bioactive Compounds from Vine Shoots, Grape Stalks, and Wine Lees: Their Potential Use in Agro-Food Chains

The winemaking sector is one of the most productive worldwide, and thus it also generates large amounts of by-products with high environmental impacts. Furthermore, global market trends and government regulations promote industrial alternatives based on sustainable production processes. As a result, several studies have focused their attention on the reuse of grape by-products in the agro-food chain. Vine shoots, grape stalks, and wine lees, although produced to a lesser extent than grape pomace, have increasingly been receiving attention for their applications in the food sector, since they are a good source of functional and bioactive compounds. In this framework, our review highlights the promising results obtained by exploiting the antioxidant and/or antimicrobial activity of vine shoots, grape stalks, and wine lees or their extracts to replace the most common oenological additives and to assay the activity against food pathogens. Further, innovative functional foods and sustainable food packaging have been formulated by taking advantage of polyphenols and fiber, as well as plant bio-stimulants, in order to obtain grapes and wines with high quality characteristics. Overall, these by-products showed the potential to be recycled into the food chain as functional additives for different products and applications, supporting the sustainability of the winemaking sector

Effect of the type of oil on the evolution of volatile compounds of taralli during storage

Baking process leads to a huge quantity of newly formed volatile compounds, which play a major role in developing the flavor of the final product. The aim of this work was to investigate on the evolution of the volatile profile of taralli as a function of both the kind of oil used in the dough and the storage time. The volatile compounds from the taralli were extracted by headspace solid-phase microextraction and analyzed by gas-chromatography/mass spectrometry (GC/MS). Forty-four volatile compounds were identified in taralli, most of which produced by thermically induced reactions occurring during baking process, such as volatiles deriving from Maillard reaction and/or sugar degradation and lipid oxidation. The results obtained demonstrated the essential role played by the type of oil on the formation and on the release of volatile compounds. The volatile compounds significantly increased during storage and their individual levels were in most cases significantly lower in taralli made with extra virgin olive oil than in those made with refined oils. Finally, the taralli made with extra virgin olive oil, compared with those prepared with other vegetable oils, showed to be more resistant to oxidation, probably due to the presence of natural antioxidants

Il profilo aromatico dei taralli

Un’indagine sperimentale è stata effettuata su taralli preparati con olio di oliva allo scopo di caratterizzarne il profilo aromatico durante la conservazione sia attraverso la tecnica analitica della microestrazione in fase solida (Solid-Phase MicroExtraction), sia attraverso la valutazione sensoriale eseguita da un panel addestrato. I risultati complessivamente ottenuti hanno evidenziato che l’analisi SPME/GCMS dei composti volatili risultava utile a valutare le caratteristiche sensoriali dei taralli nel corso della conservazione. In particolare, l’ossidazione della frazione lipidica causava un peggioramento complessivo della qualità dell’alimento e ne pregiudicava la conservazione

Use of olive leaf extract to reduce lipid oxidation of baked snacks

Olive leaves are a waste of the olive oil processing industry and represent a good source of phenolic compounds. The aim of this work was to assess the influence of olive leaf extract (OLE) on lipid oxidation of baked snacks, like breadsticks, made with wheat flour, extra virgin olive oil (EVO), white wine, and salt. Two EVOs having different peroxide value and antioxidant profile (total phenol content, tocopherols, carotenoids, and antioxidant activity) were considered. The snacks were subjected to oven test or stored in the usual conditions of retailer shelves. The obtained data highlighted that EVO plays a key role both for the quality and for the shelf-life of baked snacks and the use of OLE is recommended especially when baked snacks are produced with low quality EVO which therefore does not have a good content of natural antioxidants. The OLE addition significantly reduced the forced oxidative degradation during oven test, as evidenced by a decrease of 27% in oxidation-related volatile compounds and of 42% in triacylglycerol oligopolymers compared to control snacks (CTR) without OLE. Moreover, OLE effectively acted also in normal storage conditions, improving sensory data, induction times, antioxidant activity, and volatile compounds compared to CTR (i.e. hexanal 165.49 vs 38.31 μg g−1in OLE-added). The amount of oxidation-related volatile compounds showed an opposite trend with the quality level of oil used