Feasibility of excitation-emission fluorescence spectroscopy in tandem with chemometrics for quantitation of trans-resveratrol in vine-shoot ethanolic extracts.

BACKGROUND: trans-Resveratrol (TR) is a well-known phytochemical compound with important biological properties. It can be recovered from agri-food by-products or wastes, such as vine shoots. Once recovered, its concentration should be measured, possibly in a green, non-destructive, and efficient manner. With these premises, this work aimed to explore the feasibility of excitation-emission fluorescence spectroscopy combined with chemometrics for the analysis of TR in raw extracts obtained from vine shoots. A total of 75 extracts were produced and analyzed by ultra-performance liquid chromatography method with diode array detection (UPLC-DAD) and spectrofluorimetry. Then, the feasibility of two calibration strategies for TR quantitation was assessed - a parallel factor analysis (PARAFAC)-based calibration and the N-way partial least squares (NPLS) regression. RESULTS: The extracts showed variable TR content, the excitation/emission maxima of which were at around 305/390 nm, respectively. The best PARAFAC-based calibration allowed a root mean square error of prediction (RMSEP) of 22.57 mg L-1 , and a relative prediction deviation (RPD) of 2.91 to be obtained but a large number of PARAFAC components should be considered to improve the predictions. The results of the NPLS regression were slightly better, with a RMSEP of 19.47 mg L-1 , and an RPD of 3.33 in the best case. CONCLUSION: Fluorescence could be an alternative analytical technique to measure TR in complex samples. Chemometric tools allowed the identification of the TR signal in the fluorescence landscapes, which could be further used for its non-destructive quantitation. The need for a more accurate criterion for optimal PARAFAC complexity emerged. © 2024 Society of Chemical Industry.

Dry-fractionated protein concentrate as egg replacer in sponge cake: how the rheological properties of the batters affect the physical and structural quality of the products.

BACKGROUND: Egg replacement is a notable food trend for academics and industry. Dry-fractionated protein concentrates (DFp) are minimally processed and sustainable ingredients. DFp from chickpea, red lentil and mung bean, prepared as aqueous dispersions at 20-40% (w/w), were used to replace egg in sponge cakes. To understand the effect of DFp on the physicochemical features of sponge cakes, the batter rheological properties (i.e., flow behavior, frequency-dependent and temperature-dependent behaviors) were investigated. RESULTS: Frequency sweep revealed a higher storage modulus (G') than loss modulus (G″), indicating predominantly elastic-like behavior, dependent on the frequency. Increasing DFp content, especially at 40%, resulted in firmer batters, indicated by elevated apparent viscosity. During temperature sweep, G' increased starting from 80 °C in all DFp-based batters, indicating protein and starch conformational changes. Higher DFp content better simulated the egg behavior, affecting specific volume and thickness variation after baking but resulting in harder cakes. Crumb structure was similar to the control, highlighting that DFp can emulate the egg behavior in cake preparation. Protein content in cakes containing 30% DFp was similar to the control. However, the addition of DFp caused an increase in phytic acid. Sensory analysis of sponge cakes revealed differences in crust color, sweetness and legume flavor, with minimal effect on astringency. Chickpea and lentil DFp are suggested as preferred alternatives because of their to milder sensory impact. CONCLUSION: Overall, eggs in cake formulation can be substituted by plant-based protein produced by dry fractionation. However, further research is essential to evaluate the nutritional characteristics. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Successful Applications of NIR Spectroscopy and NIR Imaging in the Food Processing Chain.

Forty years ago, Near InfraRed (NIR) was considered a sleeping technique among the spectroscopic ones [...].

Physical-Chemical and Nutritional Characterization of Somali Laxoox Flatbread and Comparison with Yemeni Lahoh Flatbread.

The physical-chemical and nutritional characteristics of Somali laxoox and Yemeni lahoh flatbreads have not been studied to date, nor have their possible similarities been investigated. Fieldwork was carried out in Somaliland (northwest Somalia), at nine different households, to collect Somali and Yemeni flatbreads. The nutritional characteristics (12.47-15.94 g/100 g proteins, 2.47-4.11 g/100 g lipids) and the total phenolic compounds (5.02-7.11 mg gallic acid equivalents/g on dry matter) were influenced by the natural variability of manual food preparation, as well as variability in the recipes used. All the breads had a porous structure. Cell density varied from 22.4 to 57.4 cells/cm2 in the Somali flatbreads, reaching 145 cells/cm2 in the Yemeni flatbreads. Higher amounts of refined flour increased the pale color of the breads. The principal component analysis highlighted differences between Yemeni and Somali flatbreads, pointing out a certain variability within the latter, with two samples forming a separate subgroup.

Developing a Clean Labelled Snack Bar Rich in Protein and Fibre with Dry-Fractionated Defatted Durum Wheat Cake.

The shift towards a vegetarian, vegan, or flexitarian diet has increased the demand for vegetable protein and plant-based foods. The defatted cake generated during the extraction of lipids from durum wheat (Triticum turgidum L. var. durum) milling by-products is a protein and fibre-containing waste, which could be upcycled as a food ingredient. This study aimed to exploit the dry-fractionated fine fraction of defatted durum wheat cake (DFFF) to formulate a vegan, clean labelled, cereal-based snack bar. The design of experiments (DoEs) for mixtures was applied to formulate a final product with optimal textural and sensorial properties, which contained 10% DFFF, 30% glucose syrup, and a 60% mix of puffed/rolled cereals. The DFFF-enriched snack bar was harder compared to the control without DFFF (cutting stress = 1.2 and 0.52 N/mm2, and fracture stress = 12.9 and 9.8 N/mm2 in the DFFF-enriched and control snack bar, respectively), due to a densifying effect of DFFF, and showed a more intense yellow hue due to the yellow-brownish colour of DFFF. Another difference was in the caramel flavour, which was more intense in the DFFF-enriched snack bar. The nutritional claims "low fat" and "source of fibre" were applicable to the DFFF-enriched snack bar according to EC Reg. 1924/06.

Application of Agri-Food By-Products in Cheesemaking.

Agri-food companies produce large quantities of plant by-products that in many instances contain functional bioactive compounds. This review summarizes the main applications of agro-industrial by-products in cheesemaking, considering their bioactivities and functional properties. Polyphenol-rich by-products increase antioxidant and antimicrobial activity in cheeses, positively impacting their shelf life. Contrasting results have been obtained regarding the color and sensory properties of enriched cheeses depending on the selected by-products and on the technology adopted for the extract preparation. Furthermore, functional compounds in cheeses perform a prebiotic function and their bioavailability improves human health. Overall, the use of agri-food by-products in cheese formulation can offer benefits for agri-food chain sustainability and consumer health.

Screening of Acrylamide Content in Commercial Plant-Based Protein Ingredients from Different Technologies.

The demand of plant-based protein ingredients (PBPIs) in the food sector has strongly increased over recent years. These ingredients are produced under a wide range of technological processes that impact their final characteristics. This work aimed to evaluate acrylamide contamination in a range of PBPIs produced with different technologies and classified into four categories i.e., flours, dry-fractionated proteins, wet-extracted proteins, and texturized vegetable proteins. The results highlighted a remarkable variability in the acrylamide contamination in all the classes under investigation, with the flours showing the lowest mean acrylamide content (280 µg kg-1) compared with the wet-extracted proteins that showed the highest (451 µg kg-1). These differences could likely be associated with the different processing technologies used to obtain the protein ingredients. These findings suggest the need to monitor acrylamide formation during the processing of PBPIs and, consequently, to study mitigation strategies when necessary.

Impact of Milk Thermization on the Quality Characteristics of P.D.O. "Canestrato Pugliese" Ovine Hard Cheese.

The use of raw milk is compulsory in the manufacturing process of most of the European protected designation of origin (PDO) cheeses but, for ovine products, it is often responsible for faulty productions. Since pasteurization is hardly compatible with the PDO concept, a milder treatment (thermization) is allowed in some cases. An investigation was undertaken to assess the effect of thermization on the overall quality of Canestrato Pugliese, a PDO ovine hard cheese of Southern Italy that can be manufactured exclusively from raw milk. Three types of cheese were produced using raw, mild-thermized and high-thermized milk inoculated with a thermophilic commercial starter. The results demonstrated that the heat treatment did not cause remarkable differences in the gross composition, but the microbiological profiles had some differences despite the use of the selected starter. The raw milk cheese contained higher levels (0.5-1 log units) of mesophilic lactobacilli, total viables, total coliforms and enterococci with respect to the thermized counterparts, with the high-thermized cheese showing the lowest levels; these microbiological differences fitted well with the higher content and the different High Performance Liquid Chromatography (HPLC) pattern of soluble nitrogen. The sensory analysis revealed that the thermized cheeses lost some typical sensory characteristics, probably as a consequence of the reduced indigenous microbiota populations. It was concluded that milk thermization could be applied to Canestrato Pugliese manufacturing only together with the development and use of an autochthonous starter.

Almond okara as a valuable ingredient in biscuit preparation.

BACKGROUND: The okara is the water-insoluble residue derived from the production of plant-based beverages, including almond milk. Information on almond okara is scarce, with no scientific references. In the present study, the almond okara was characterized and used to replace wheat flour at 15%, 25% and 35% for biscuit preparation. RESULTS: The contents of protein, lipid and dietary fiber of almond okara were 140.08, 421.16 and 407.90 g kg-1 dry matter, respectively. The lipid fraction of almond okara showed contents of triacylglycerol oligopolymers and oxidized triacylglycerols of 0.12 and 5.14 g kg-1 , respectively, which were significantly lower than the levels observed in the sunflower oil used in the formulation of biscuits. Consequently, the biscuits containing okara showed a content of triacylglycerol oligopolymers lower than that of control biscuits. The texture analysis revealed that the addition of the okara at 25% and 35% caused a significant increase in biscuit hardness and a reduction of the brittleness, compared to the control. The sensory evaluation confirmed these data, highlighting the slight impact of the almond okara on the almond odor, taste and flavor attributes. CONCLUSION: Almond okara is a valuable by-product that can be easily used as an ingredient for biscuit preparation, exploiting its fiber, protein and lipid content to improve the nutritional value of food, with a limited impact on the sensory properties. © 2022 Society of Chemical Industry.

TXRF spectral information enhanced by multivariate analysis: A new strategy for food fingerprint.

The increased costumers' request of safe and high-quality food products makes food traceability a priority for frauds identification and quality certification. Elemental profiling is one of the strategies used for food traceability, and TXRF spectroscopy is widely used in food analysis even if its potentialities have not been fully investigated. In this work, a new method for food traceability using directly TXRF spectra coupled with multivariate analyses, was tested. Twenty-four different beans' genotypes (Phaseolus vulgaris L.) grown onto two different sites have been studied. After the development of the method for beans' analysis, TXRF spectra were collected and processed with PCA combined with SNV and GLSW filter obtaining a perfect clustering of the seeds according to their geographical origin. Finally, using PLS-DA, beans were correctly classified demonstrating that TXRF spectra can be successfully used as fingerprint for food/seed traceability and that elemental quantification procedure is not necessary to this aim.

The Use of Durum Wheat Oil in the Preparation of Focaccia: Effects on the Oxidative Stability and Physical and Sensorial Properties.

Durum wheat oil is an innovative oil that could be considered the "second life" of durum wheat milling by-products. In this study, we proposed the use of this oil in the reformulation of a traditional Italian greased flat bread, namely focaccia, whose typical sensorial features are due to the presence of relevant amounts of oil in its formulation. The chemical, physical, and sensorial features of focaccia with durum wheat oil (DWO) were compared with those of focaccia prepared with olive oil (OO) and sunflower oil (SO). The results showed the prevalence of polyunsaturated fatty acids in DWO, followed by SO. DWO was more resistant to oxidation than SO (induction time 86.2 and 66.3 min, respectively), due to its higher content of tocotrienols (1020 and 70.2 mg/kg in DWO and SO, respectively), but was less resistant than OO, richer in monounsaturated fatty acids, and contained phenolic compounds. The volatile oxidation markers, namely hexanal and nonanal, were less prevalent in OO and DWO than in SO. Texture and color were positively influenced by the use of durum wheat oil, allowing the nutritional improvement of this flat bread in a sustainable and circular manner.

Optimization of formulation and physicochemical, nutritional and sensory evaluation of vegan chickpea-based salad dressings.

The formulation of a vegan salad dressing supplemented with chickpea flour (VC-SD) was optimized by D-optimal mixture design, evaluating the effect of chickpea flour, water and oil on the textural properties of the product. The linear models showed the best fitting and predictive ability, as highlighted by high R2 adj and Q2. The Cox-effects of the textural parameters were significant for water and chickpea flour contents, but not for oil. Sensory evaluation indicated that all the VC-SD were characterized by the predominance of pungent/acid odor notes, whereas sourness was the most perceived fundamental taste, together with a sensation of a grainy texture in mouth due to flour particles. Overall, the product can be consumed by vegans and vegetarians because produced without animal-derived ingredients, and is in synergy with the healthful characteristics of Mediterranean diet, in which pulses and extra-virgin olive oil play beneficial roles. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05288-x.

Characterization and Effect of Refining on the Oil Extracted from Durum Wheat By-Products.

Durum wheat is one of the most important cereal grains worldwide, used mostly for pasta making and bakery products. The by-products derived for the milling process, although very abundant, have only limited use. The aim of this work was to characterize the oils extracted from the by-products of debranning (DP) and milling processes (MP) of durum wheat and to follow the changes due to the refining process on the minor components. The results showed that DP had significantly higher oil content than MP, but it was characterized by a significantly lower amount of tocols. Polyunsaturated fatty acids content was similar (around 62% of total fatty acids). Consequently, a mixture of DP/MP (60/40 w/w) was chosen as a basis for further studies concerning the refining process. During refining, carotenoids almost disappeared while tocols were reduced by 24% on average. Free fatty acids, peroxide value, and oxidized triacylglycerols were significantly reduced by refining, while triacylglycerol oligopolymers were significantly higher than the crude oil. Durum wheat oil had an outstanding content of phytosterols and policosanols. Overall, the edible oil obtained from durum wheat after refining could be considered a good source of phytochemicals and could represent a valuable strategy to valorize the by-products from durum wheat mills.

Vine Shoots as a Source of Trans-Resveratrol and ε-Viniferin: A Study of 23 Italian Varieties.

Stilbenes are a family of phenolic secondary metabolites that are known for their important roles in plant protection and human health. Numerous studies show that vine shoots, one of the most abundant winery wastes, could be used as a source of bioactive compounds such as stilbenes. The predominant stilbenoids in vine shoots are trans-resveratrol (Rsv) and ε-viniferin (Vf), whose content varies depending on numerous intrinsic and extrinsic factors. The present work investigates the influence of pre-treatment and variety on stilbene concentration in vine shoots. Vine shoots of the Primitivo and Negroamaro varieties were submitted to four different trials before stilbene extraction (untreated, dried at 50 °C for 24 h, dried at 70 °C for 15 min, and dried at 80 °C for 10 min). The results showed that the heat pre-treatments had a slight impact on the total phenol and stilbene content. In contrast, the variety variable had a stronger impact on stilbene concentration, ranging from 2700 to 6400 mg kg-1 DW for untreated vine shoots of 23 Italian varieties. In all vine shoots, the most abundant stilbene compound was Rsv and the highest content was found in vine shoots of the Nero di Troia (5298.1 mg kg-1 DW) and Negroamaro (5249.4 mg kg-1 DW) varieties.

Bioactive Potential of Minor Italian Olive Genotypes from Apulia, Sardinia and Abruzzo.

This research focuses on the exploration, recovery and valorization of some minor Italian olive cultivars, about which little information is currently available. Autochthonous and unexplored germplasm has the potential to face unforeseen changes and thus to improve the sustainability of the whole olive system. A pattern of nine minor genotypes cultivated in three Italian regions has been molecularly fingerprinted with 12 nuclear microsatellites (SSRs), that were able to unequivocally identify all genotypes. Moreover, some of the principal phenolic compounds were determined and quantified in monovarietal oils and the expression levels of related genes were also investigated at different fruit developmental stages. Genotypes differed to the greatest extent in the content of oleacein (3,4-DHPEA-EDA) and total phenols. Thereby, minor local genotypes, characterized by stable production and resilience in a low-input agro-system, can provide a remarkable contribution to the improvement of the Italian olive production chain and can become very profitable from a socio-economic point of view.

Near Infrared Spectroscopy as a Green Technology for the Quality Prediction of Intact Olives.

Poorly emphasized aspects for a sustainable olive oil system are chemical analysis replacement and quality design of the final product. In this context, near infrared spectroscopy (NIRS) can play a pivotal role. Thus, this study aims at comparing performances of different NIRS systems for the prediction of moisture, oil content, soluble solids, total phenolic content, and antioxidant activity of intact olive drupes. The results obtained by a Fourier transform (FT)-NIR spectrometer, equipped with both an integrating sphere and a fiber optic probe, and a Vis/NIR handheld device are discussed. Almost all the partial least squares regression models were encouraging in predicting the quality parameters (0.64 < R2pred < 0.84), with small and comparable biases (p > 0.05). The pair-wise comparison between the standard deviations demonstrated that the FT-NIR models were always similar except for moisture (p < 0.05), whereas a slightly lower performance of the Vis/NIR models was assessed. Summarizing, while on-line or in-line applications of the FT-NIR optical probe should be promoted in oil mills in order to quickly classify the drupes for a better quality design of the olive oil, the portable and cheaper Vis/NIR device could be useful for preliminary quality evaluation of olive drupes directly in the field.

Background, Applications and Issues of the Experimental Designs for Mixture in the Food Sector.

BACKGROUND: Mixtures play a key role in Food Science and Technology. For studying them, rational approaches should be used. In detail, the experimental designs for mixtures are useful tools for studying the effects of ingredients/components in formulations. RESULTS: Food Science and Technology is the fourth category among the total records considered in this review. The applications span from food formulation to the composition of modified atmosphere, shelf-life improvement and bioactives extraction. However, the majority of the studies regards few products and ingredients. Simplex-lattice and simplex-centroid designs are the most common used, although some optimal designs, such as the D-optimal, have also interesting applications. Finally, some issues are highlighted, which basically regard the interpretation of the models coefficients and the lack of model validation. CONCLUSION: In the last decade, mixture designs have been fairly used in the field of Food Science and Technology. Modeling the response(s) allows researchers to achieve a global knowledge of the system under study within the defined experimental domain. However, the majority of application has regarded limited classes of products, and thus an increase in the spectrum of applications is desired.

Antinutritional factors, mineral composition and functional properties of dry fractionated flours as influenced by the type of pulse.

Coarse (CF) and Fine (FF) fractions were obtained by dry fractionation (air classification) of raw micronized flour (RM) of kabuli chickpea, green pea, yellow and red lentil. Pea showed the highest phytate content in RM and CF. Stachyose was the main oligosaccharide in lentils, exceeding 50 mg g-1, whereas raffinose (39.9 mg g-1) was abundant in chickpea. Antinutritional factors were significantly enriched in FF, whereas decreased in CF. Total-reflection X-ray fluorescence identified potassium as the main macronutrient in pulses. Ca was highly variable, ranging from 0.92 to 0.28 g kg-1 in pea and yellow lentil, respectively. A significant shift of minerals was observed in FF, but despite the highest phytate content, phytate:Zn ratio of lentils was lower than RM, indicating that Zn was enriched more than phytates. Yellow lentil and pea FF showed a protein content higher than 55 g 100g-1. Dry fractionation significantly affected the physicochemical properties, indicating different potential use of fractions.

The Potential of Apulian Olive Biodiversity: The Case of Oliva Rossa Virgin Olive Oil.

In this study, the drupes and virgin olive oils extracted from the Oliva Rossa landrace are characterized. Oliva Rossa is an old landrace part of the autochthonous Apulian olive germplasm for which only few data have been reported till now. During the study, the maturity patterns of the drupes had been followed. Four samplings per year were planned, one every 14 days starting from the middle of October. The pigmentation index, the oil content and the total phenolic content of the drupes were measured. Simultaneously, virgin olive oils were extracted at the lab scale and analyzed for the fatty acid composition, the basic quality parameters and the content of minor compounds. The pigmentation pattern of the drupes was different among the years and, despite this trend, at the third sampling time the stage of maximum oil accumulation was always over. The extracted virgin olive oils had a medium to high level of oleic acid. With colder temperatures, a higher level of monounsaturated fatty acids, oleic/linoleic ratio and antioxidants was observed. The phenolic profile was dominated by 3,4-DPHEA-EDA and p-HPEA-EDA while the volatile profile by (E)-2-hexenal and 3-ethyl-1,5-octadiene.

Supercritical CO2 Extraction of Phytocompounds from Olive Pomace Subjected to Different Drying Methods.

Olive pomace is a semisolid by-product of olive oil production and represents a valuable source of functional phytocompounds. The valorization of agro-food chain by-products represents a key factor in reducing production costs, providing benefits related to their reuse. On this ground, we herein investigate extraction methods with supercritical carbon dioxide (SC-CO2) of functional phytocompounds from olive pomace samples subjected to two different drying methods, i.e., freeze drying and hot-air drying. Olive pomace was produced using the two most common industrial olive oil production processes, one based on the two-phase (2P) decanter and one based on the three-phase (3P) decanter. Our results show that freeze drying more efficiently preserves phytocompounds such as α-tocopherol, carotenoids, chlorophylls, and polyphenols, whereas hot-air drying does not compromise the ß-sitosterol content and the extraction of squalene is not dependent on the drying method used. Moreover, higher amounts of α-tocopherol and polyphenols were extracted from 2P olive pomace, while ß-sitosterol, chlorophylls, and carotenoids were more concentrated in 3P olive pomace. Finally, tocopherol and pigment/polyphenol fractions exerted antioxidant activity in vitro and in accelerated oxidative conditions. These results highlight the potential of olive pomace to be upcycled by extracting from it, with green methods, functional phytocompounds for reuse in food and pharmaceutical industries.