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In order to give insight into β-carotene degradation mechanism during the storage of dried orange-fleshed sweet potato, and particularly into the role of isomers and norisoprenoids formation, multi-response kinetic modelling was applied. Determination of degradation compounds were carried out by HPLD-DAD and SPME-GC-MS as a function of time between 10 and 40 °C and at four water activities from 0.13 to 0.76. Kinetic modelling was developed assuming first-order reactions and by using mass balance. Eight compounds, namely, two isomers (9- cis- and 13- cis-β-carotene), two β-carotene epoxides (β-carotene 5,6 and 5,8 epoxide) and four volatile compounds (β-cyclocitral, β-ionone, 5,6-epoxy-β-ionone and dihydroactinidiolide), were integrated into two theoretical reaction schemes. The different models were discriminated according to goodness of fit to experimental data. This work showed that: (1) the formation of cis-isomers from β-carotene preceded oxidation, (2) β-cyclocitral arose directly from β-carotene scission while the other norisoprenoids resulted from β-carotene epoxide degradation, (3) cis-isomers were high reactive compounds. Temperature had a major influence on reaction rates k while water activities only impacted k at values under 0.51. Therefore, multi-response modelling is not only a tool to predict β-carotene degradation but a interesting way to select the appropriate degradation scheme based on the different options presented in literature. [ABSTRACT FROM AUTHOR]

Introduction. Detarium senegalense J.F. Gmel is a forest tree found in Senegal whose fruits are locally called ditax in Wolof. It is eaten fresh but it is widely used as nectar, which is one of the most popular beverages in Senegal. However, the chemical characterization of ditax pulp remains incomplete. This paper describes the volatile compounds of ditax to assess its organoleptic qualities. Materials and methods. Free volatile compounds of fresh ditax pulp were isolated by solvent-assisted flavor evaporation and analysis by GC-MS. Results and discussion. Among the 53 compounds tentatively identified, 49 are reported for the first time in this fruit. In total, 17 aldehydes, 11 aliphatic alcohols, 1 terpene alcohol, 7 free fatty acids, 3 unsaturated hydrocarbons, 1 terpene hydrocarbon, 7 sesquiterpene hydrocarbons, 1 phenol, 2 ketones, 2 esters and 1 organic acid compound were tentatively identified in ditax fresh pulp. The main volatiles identified in fresh ditax pulp were trans, cis-2,6-nonadienal (2.47 mg×kg–1), cis-2-heptenal (1.93 mg×kg–1), trans-a-bergamotene (1.11 mg×kg–1), bicyclo [2,2,0] hexane-1-carboxaldehyde (0.80 mg×kg–1), butyl octadecanoate (0.55 mg×kg–1) and trans-2-nonenal (0.47 mg×kg–1 fresh pulp). Conclusion. Among the volatile compounds identified, aldehyde compounds were widely predominant. To assess the aromatic qualities of ditax pulp, the primary impact aromas should be determined by identifying the aroma-active compounds by GC-olfactometry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Neither pasteurization nor high pressure treatments altered carotenoid content. • UHPH led to the concentrate with the highest bioavailable carotenoid content (BCC) • Carotenoid uptake is linked to micelle size and degree of methylation of pectins. • CFM/UHPH combination multiplied BCC in the concentrate by up to 6 compared to the juice. High-pressure treatments combined with crossflow microfiltration were used to obtain citrus concentrates enriched in carotenoids. The aim of this study was to investigate the effect of this process combination on carotenoid bioaccessibility and uptake by intestinal Caco-2 cells. Two high-pressure processes, high hydrostatic pressure treatment (HHP) and ultra-high-pressure homogenization (UHPH) were compared to conventional pasteurization. Processing effects on carotenoid content and bioaccessibility, on physicochemical and structural characteristics of the product, on methylation degree of pectins and micelle size after in vitro digestion were assessed. UHPH at 400 MPa drastically enhanced carotenoid bioaccessibility compared to HHP and pasteurization. Moreover, carotenoid uptake by Caco-2 cells was significantly improved by UHPH underlining the importance of the micelle size after in vitro digestion and the degree of methylation of pectins in this uptake. Finally, the in vitro bioavailable carotenoid content of different concentrates was evaluated, taking into account carotenoid content, bioaccessibility and uptake. Combining crossflow microfiltration with UHPH increased by 4–6 fold the bioavailable carotenoid content in the final product. The process led to a concentrate of high nutritional quality compared to the original juice, raw or pasteurized concentrates. [ABSTRACT FROM AUTHOR]

Introduction The effect of temperature on the stability of three purified anthocyanin sources in a soft drink (pH 3, 10 °Brix) stored at (4, 20, 30 and 50) °C for 60 days was investigated. Materials and methods. Anthocyanins from Andean blackberries (Rubus glaucus Benth.), açai (Euterpe oleracea Mart.) and black carrot (Daucus carota L.) were purified and concentrated on a laboratory scale by adsorption to a styrene divinylbenzene copolymer. Two classical empirical approaches (Arrhenius and Ball models) were used to describe the thermal degradation kinetic of these three anthocyanins. Results. No degradation was detected during the refrigerated storage (4 °C). At all temperatures, the degradation rate constant (k) for black carrot anthocyanins was less than those in açai and blackberry (0.42 × 10-2, 0.77 × 10-2 and 1.08 × 10-2).d-1 respectively, at 30 °C). Anthocyanins in black carrot degraded less rapidly than those in açai and Andean blackberry. The activation energy (Ea) for degradation of black carrot anthocyanins was (63.2 ± 4.3) kJ.mol-1, and (66.3 ± 2.7) kJ.mol-1 and (91.2 ± 0.4) kJ.mol-1 for açai and blackberry anthocyanins, respectively, at 20–50 °C. These higher Ea of blackberry anthocyanins as compared with those of black carrot and açai imply that a small temperature increase is sufficient to degrade them more rapidly. Conclusion. Our results clearly showed that anthocyanins from black carrot have a good stability during thermal storage (4 °C to 50 °C) with regard to blackberry and açai anthocyanins. Acylation of black carrot anthocyanins probably explains their greater stability. Acylated anthocyanins have shown to be promising alternatives to the use of synthetic dyes in drink systems [ABSTRACT FROM PUBLISHER]

The açai juice is an Amazonian product that has been exported to various countries around the world. Its main characteristic is the presence of antioxidant compounds especially anthocyanins. Nanofiltration is a membrane separation process that has the ability to separate compounds of low molar weight. Açai juice clarified by microfiltration was used as feed to evaluate nanofiltration membranes of different manufacturers regarding the permeate flux and the retention of anthocyanins. All the evaluated membranes were efficient in retaining the anthocyanins from the açai juice. NF 270 membrane, a composite membrane composed by a polyamide top layer and a polysulphone microporous support, presented the highest water permeability before and after the nanofiltration of açai juice. In addition, this membrane also presented the highest value of permeate flux in the nanofiltration process of açai juice as well as the anthocyanins retention above 99%. The effect of fouling for this membrane was approximately 28%. The observed results showed the potential of nanofiltration on the recovery of anthocyanins from açai fruit. [ABSTRACT FROM AUTHOR]

The lactoperoxidase system (LPS) was evaluated for the prevention of postharvest diseases caused by Xanthomonas campestris, Botryodiplodia theobromae, and Colletotrichum gloeosporioides in 'Keitt' and 'Kent' mangoes. The LPS treatment significantly reduced the disease development on both cultivars after storage at 12°C for 2 weeks, which was followed by a ripening at 25°C. The LPS treatment did not alter the sensory quality of mango fruits (color, firmness, titrable acidity, and total soluble solids) when compared to untreated fruits. The LPS thus presents good potential alternative to the chemical fungicides traditionally used to improve the shelf life of mangoes. [ABSTRACT FROM AUTHOR]

The antibacterial activity of the lactoperoxidase system (LPS) on the growth of Xanthomonas campestris, the causal agent of bacterial black spot in mangoes. Botryodiplodia theobromae, the causal agent of stem-end rot disease in mangoes, and Colletotrichum gloeosporioides, the causal agent of anthracnose disease in mangoes, was determined during culture at 30°C and at several pH values (4.5, 5.5. and 6.5). When the results of using the LPS were compared with those from control cultures without the LPS reagents, the growth of the three microorganisms was totally inhibited in all of the conditions tested. Viability tests enumerating cultivable cells of X. campestris showed that the LPS had a bactericidal effect, whatever the pH value. This effect is faster at pH 5.5, corroborating the results reported in the literature (optimal pH for the LPS efficiency). Further, we proved that hydrogen peroxide alone had little inhibition effect on the growth of the microorganisms studied. This compound is essentially used to convert thiocyanate into hypothiocyanate during the lactoperoxidase reaction. The potential of the LPS for the postharvest treatment of the fruits for controlling microbial diseases was thus demonstrated. Nevertheless, further studies are needed on fresh fruits before envisaging any application. [ABSTRACT FROM AUTHOR]

Crossflow microfiltration was implemented to enrich a clementine/pink grapefruit juice in carotenoids, flavonoids and pectins modulating its sugar content thanks to an added diafiltration step. Using tubular ceramic membrane with pore diameter of 0.2 μm at 30–40 °C, a crossflow velocity of 5 m‧s−1 and a transmembrane pressure of 2.6 bar, the impact of the process was assessed focusing on bioactive compounds and physical characteristics of the concentrates. With permeate flux above 30 kg‧h−1‧m−2, the process resulted in an increase of 8–10 times in the content of provitamin A carotenoids (33 mg‧kg−1 in the final products), lycopene (43 mg‧kg−1), hesperidin (3.2 g‧kg−1) and pectin (5.5 g‧kg−1) giving a unique and interesting composition profile. Moreover, diafiltration divided the sugar content by 3. This can be relevant for the product to be recommended as part of a reduced sugar diet for diabetic people. By modelling the retention of bioactive compounds, we showed that it was possible to modulate sugar, flavonoids, carotenoids and pectin contents in the concentrate that could be a key issue for the biological activity of this potential functional citrus-based food. • Modulation of citrus bioactive compounds through crossflow microfiltration. • A citrus-based food enriched 8-fold in carotenoids, flavonoids and pectins. • Diafitration allowed to divide by 3 sugar content of the citrus-based food. • Modelling useful to find operating conditions, for a targeted composition profile. [ABSTRACT FROM AUTHOR]

The design of food processing plants that are plug-and-play, reconfigurable, modular, mobile and containerised is a complex task. The "Methodology for the integrated, multi-scale and multi-objective design of systems" can be used to design such systems. This was developed and the various tasks that make it up presented in a previous article by Savoure et al. (2023) (references to be specified). The aim of this study is to assess the potential of this methodology to design a mobile fruit and vegetable processing unit. Firstly, a design support tool was developed to (i) simulate the behaviour and estimate the performances of design solutions, (ii) convert their performances into desirability indices using the decision maker's preferences and (iii) search for the design solution(s) that best satisfy the decision maker's design objectives. The results were then visualised and analysed to ensure that the resulting design solution was a satisfying, feasible and coherent trade-off. This analysis also helped to understand (i) which design variables, models and assumptions drove the design decision the most and (ii) which final products, design objectives, performance indicators and preference models influenced the optimisation process the most. In particular, it showed that one of the products (okra puree) limited the performance of the design solution. Finally, this work increased the level of understanding of the design problem and challenged the preferences of the decision maker. [ABSTRACT FROM AUTHOR]

The design of batch food processing plants is complex which requires the use of advanced simulation and optimisation methods. This paper presents how existing methods for multi-scale design and multi-objective optimisation can be combined together while carrying out the integrative design of these complex systems. To implement the Methodology for the Integrated, Multi-scale and Multi-Objective Design of Systems (MIMMODS), 8 tasks must be completed. The goal of the first 6 tasks is to build a design support tool that (i) simulates the behaviour of the processing plant and estimates its performance at different functional levels and whatever design variables it is made up of, (ii) takes into account the preferences of the decision-maker to convert the performances of a design solution into desirability indices and (iii) searches for the design solution(s) that best satisfies the design objectives and the preferences of the decision-maker. When the design support tool is functioning, the results have to be visualised and analysed in order to validate whether the resulting design solution is satisfactory, realistic, feasible and consistent or whether a new iteration of the methodology needs to be conducted to refine the design support tool. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate an eco-friendly process based on microfiltration with a diafiltration stage in order to concentrate and purify the main carotenoids and flavonoids in citrus juices. Pilot plant scale trial parameters were: tubular ceramic membranes with 0.2 μm pore diameter, 40 °C and 3 bar of transmembrane pressure. Different operating conditions were tested varying volumetric reduction ratio (VRR) from 2.5 to 10 and diavolume (DV) up to 1.7. Permeate flux ranged from 20 to 100 L h − 1 m − 2 according to the VRR. The concentration was multiplied by 5 to 10 for carotenoids and hesperidin but only by 2 to 3 for narirutin. Diafiltration increased the purity of carotenoids and hesperidin from 8 to 20 times. A model was validated for prediction of the concentration and purification factors vs. VRR and DV and the retentions were 100%, 97% and 63% for carotenoids, hesperidin and narirutin. [ABSTRACT FROM AUTHOR]

An innovative process combining roasting and tempering was proposed to promote puffing and mechanical dehulling of jicaro seeds. Roasting was performed at three temperatures (120 °C, 140 °C, and 160 °C) and for six residence times (80–180 s). A previous seed tempering was performed at 15% moisture content for 24 h, by spraying the seeds with an amount of water calculated to reach the final moisture content of 15%. The following parameters were monitored as a function of time to optimize the roasting operation: percentage of open seeds, whiteness of cotyledons, and content of two volatile compounds, 2,5-dimethylpyrazine and ethyl-2-methylbutyrate which are considered as the key jicaro note. The optimal roasting was achieved at 160 °C for 150 s with 90% open seeds. The optimal mechanical dehulling was achieved after tempering the roasted seed at 10% moisture content with a yield of 75%. The lightness evolution followed a zero-order kinetic with an activation energy of 103 kJ mol −1 . Ethyl-2-methylbutyrate and 2,5-dimethylpyrazine increased with the temperature and period of roasting. [ABSTRACT FROM AUTHOR]

Highlights: [•] Camu–camu juice was pre-concentrated by reverse osmosis (RO) up to 285gkg−1. [•] Osmotic pressure was the main factor affecting the permeate flux during RO. [•] The juice was further concentrated by osmotic evaporation (OE). [•] OE resulted in a juice with 530gkg−1 of soluble solids. [•] Bioactive compounds of camu–camu juice were concentrated up to 7times. [Copyright &y& Elsevier]

Abstract: The effect of water activity on anthocyanin degradation and non-enzymatic browning (NEB) indices was determined in a blackberry juice system heated to high temperature. Blackberry juice samples mixed with quartz sand at three different water activities (a w of 0.34, 0.76 and 0.95) and having the same concentration of anthocyanins (51±4mg100g−1 WB) were heated in a hermetically sealed reactor under non-isothermal conditions (100 to 140°C). Reaction kinetics were well-represented by first-order reaction models. A non-isothermal method was used for the identification of kinetic parameters, and the confidence interval for each parameter was determined via Monte-Carlo simulations. The estimated parameters revealed an increase in the anthocyanin degradation reaction rate constant (k ref ) from 0.9 to 3.5×10−3 s−1 as the water activity decreased from 0.99 to 0.34. The corresponding activation energies (E a ) for anthocyanins and NEB index were modified to a lesser extent by variations in water activity. Hence, the reduction of water activity had a negative effect on anthocyanin stability at high temperatures. [Copyright &y& Elsevier]

The high acidity of passion fruit limits its addition in food preparation. In order to easy the uses of this juice to formulate high aroma and flavour products, its citric acid content must be decreased. Various methods such as calcium salts precipitation, ion-exchange resins and electrodialysis with homopolar and bipolar membranes were investigated to increase the pH of a clarified passion fruit juice from 2.9 to 4.0. Each deacidification process was compared in terms of characteristics of deacidified juices such as concentration of inorganic and organic ions, colour and flavour. The deacidification by precipitation using CaCO3 was not recommended because of CO2 release. The ion-exchange process gave a poor quality juice in terms of organoleptic characteristics. Electrodialysis with homopolar membranes induced an increase in the sodium concentration. Precipitation with Ca(OH)2 and electrodialysis with bipolar membrane were the most suitable processes in terms of sensorial properties of juices treated. The physico-chemical analyses showed an increase in the calcium concentration with the use of Ca(OH)2 that could cause some precipitation problems in the final product. Inorganic anions were eliminated together with citrate by using electrodialysis and resins. Nevertheless, electrodialysis with bipolar membranes presented great advantages: it was a continuous process without reagent addition moreover allowing the production of a valuable solution of citric acid. [Copyright &y& Elsevier]

This work focused on an eco-friendly process to concentrate carotenoids from a citrus juice formulated with clementine and pink grapefruit. It is based on crossflow microfiltration associated with enzymatic liquefaction, diafiltration and pasteurization. The aim was to evaluate the impact of the main operating conditions on the process performance and on the nutritional quality of the final concentrate taking into account the bioaccessibility of β-carotene, β-cryptoxanthin and lycopene. First, the best enzyme/pressure/membrane combination was chosen in order to maximize permeate flux during microfiltration (>100 kg.h−1.m−2 at 2.6 bar with tubular inorganic membranes). Second thanks to a Plackett-Burman experimental design applied to the whole process, we showed the enzymatic dose was the most impacting parameter on carotenoid bioaccessibility and it decreased it. An optimal dose of enzyme had to be defined in order to obtain a good compromise between the process performance and the nutritional quality of the citrus concentrate. • Process combining enzyme liquefaction, microfiltration, diafiltration, pasteurization. • The most influential step on carotenoid bioaccessibility was the enzyme treatment. • Low enzymatic dose ensured high process performance without reducing bioaccessibility. • No correlation between particle size, viscosity and carotenoid bioaccessibility. • In optimal conditions, the whole process multiplied the bioaccessible carotenoid content by 4.8. [ABSTRACT FROM AUTHOR]

Summary: Slices (1.5 mm thick) of green papaya were impregnated through osmotic dehydration with a blackberry juice–sucrose solution to produce an intermediate moisture product. The effect of processing temperature (T) and sucrose‐added molality (msucrose) on mass transfer during the operation was assessed, using a response surface methodology (RSM). The RSM was used to model water loss, sugar and anthocyanin gain during the process. Increasing sucrose molality resulted in increasing water loss and sugar gain, but decreasing anthocyanin gain. Water transfer therefore limits anthocyanin impregnation, but not sucrose incorporation. Afterwards, the impact of heat treatment at high temperatures was analysed, using numerical simulation. The conditions of the combined process, designed to achieve an anthocyanin‐rich final product, are low sucrose‐added molalities (sucrose molality < 1 mol kg–1) and high processing temperatures (T > 50 ºC) for osmotic dehydration, coupled with high‐temperature, short‐time (HTST) heat treatments for product stabilisation. [ABSTRACT FROM AUTHOR]

In this study, coffee pulp was used as carbon source in solid-state fermentation to produce a phenol-rich extract for industrial applications. Fermentations were carried out at laboratory (0.4kg), semi-pilot (12kg) and pilot (90kg) scales in presence of 2.5 g kg-1 yeast strains and with three different coffee pulp materials. The extract stability was investigated using different stabilizing agents: SO2, ascorbic and acetic acids. Then, a study was conducted to determine the effect of ultrasound treatment on extraction yields. Results showed that higher concentrations of chlorogenic acids were obtained with fermentation without ultrasound treatment and by adding sulfite at 0.5 wt% at 8 h of fermentation. Despite of variations in coffee pulp composition, the process was validated at semi-pilot and pilot scales, providing an extract 400% richer in chlorogenic acids (600 mgkg of coffee pulp) and with lower sugar amounts to separate during the downstream processing. [ABSTRACT FROM AUTHOR]

Abstract An integrated process coupling crossflow micro and ultra or nanofiltration was applied to separate the betacyanins in cactus pear juice (30 °C). Four microfiltration ceramic membranes (0.1–0.2 μm, 1.8–3.3 bar) and 4 ultra/nanofiltration organic membranes (0.2–4.0 kDa, 5–30 bar) were tested. Microfiltration was a first step to remove insoluble solids with low retention of soluble solids. By coupling with enzymatic liquefaction, permeate flux Jp was increased by 2 and the retention of betacyanins was limited. Ultra/nanofiltration was then used for solute separation. Retentions of solutes could be modulated by varying membrane/pressure combinations that favor rather the concentration of all the solutes or rather the purification of the betacyanins with respect to the total dry matter. Retention of individual betacyanins could be a little different which also made possible fractionation. Simulations using simple models allowed to evaluate the interest of the process for concentrating, purifying and fractionating betacyanins with a possible diafiltration step. Industrial relevance Betacyanins are natural colorants that can be obtained from cactus pear juice, a crop of increasing interest for its agricultural potential in Sahelian regions. The aim of this study was to evaluate a new integrated process based on membrane separation allowing to concentrate or separate betacyanins from other solutes at low temperature and with a limited environmental impact. This process associates a first step to clarify the cactus pear juice by microfiltration after enzymatic liquefaction and a second step to concentrate or purify betacyanins by ultra or nanofiltration. By choosing different membrane/transmembrane pressure combinations in the 2nd step, solute retentions could be modulated in order to favor rather the concentration of all solutes or rather the separation of betacyanins from total soluble solids or even rather the fractionation of betacyanins themselves. Highlights • Coupling micro and ultra/nanofiltration to separate betacyanins in cactus pear juice • Microfiltration with enzymatic liquefaction for clarifying with low solute retention • Ultra/nanofiltration for concentrating or purifying betacyanins • Separation pattern modulated thanks to different membrane/pressure combinations [ABSTRACT FROM AUTHOR]

The purpose of this study was to screen for the first time, Pinus halepensis seeds for their antinutritional factors (ANFs) and to reduce them through processing. Results of ANF screening showed that Aleppo pine seeds contained negligible amounts of tannins, saponins and alkaloids, and no amylase and trypsin inhibitory activities. However, they contained significant amounts of phytates and oxalates with values of 2.63 ± 0.21% and 1.07 ± 0.09% respectively. A dehulling operation to remove the adhering coat was implemented which contributed to a reduction of 25% of phytates and 46% of oxalates. Soaking seeds were studied and optimized using a Box Behnken experimental design, varying soaking time, temperature, and pH. The desirability study allowed the determination of optimal conditions of 10.6 h soaking time, 57.6 °C soaking temperature and 5.54 pH that decreased oxalate and phytate content by 72% and 61% respectively. Production of a plant-based beverage with these optimal process conditions markedly reduced the antinutrient content while maintaining expected dry matter, color, stability and pH. • First study of ANFs in Aleppo pine seeds. • The ANFs present are oxalates and phytates. • Dehulling eliminates almost half of these ANFs. • Soaking is an effective process for removing ANFs. • Treatment of seeds has no negative impact on its beverage. [ABSTRACT FROM AUTHOR]

Highlights • UV–VIS spectral evolution during storage of Hibiscus Sabdariffa calyces extract. • MCR-ALS done on fractionated and whole extract spectra. • Spectral discrimination of different polyphenols and condensed products. • Recovering of concentration profiles during storage. Abstract This study aims to monitor composition changes in an anthocyanin-rich beverage during storage by the means of UV–VIS measurements associated with a multi-curve resolution procedure. Hibiscus sabdariffa extract was stored at 37 °C for 50 days and UV–VIS spectra were measured on the extract and the fractions of the extract every 5 days. MCR was carried out in two steps, first with the fraction and then the extract spectra. The results enabled the main polyphenols initially present to be identified, anthocyanins and chlorogenic acid, but also found the nature of the main degradation products: the polymers from anthocyanin condensation and scission products. In addition, comparison with HPLC analysis results showed that the MCR procedure recovered the correct shapes of the concentration profiles particularly of anthocyanin and polymer kinetics during storage. This work gives perspective for the use of a rapid and efficient technique to monitor pigment-rich beverage processing or storage. [ABSTRACT FROM AUTHOR]

Effect of oxygen, polyphenols and metals was studied on degradation of delphinidin and cyanidin 3- O -sambubioside of Hibiscus sabdariffa L. Experiments were conducted on aqueous extracts degassed or not, an isolated polyphenolic fraction and extract-like model media, allowing the impact of the different constituents to be decoupled. All solutions were stored for 2 months at 37 °C. Anthocyanin and their degradation compounds were regularly HPLC-DAD-analyzed. Oxygen concentration did not impact the anthocyanin degradation rate. Degradation rate of delphinidin 3- O -sambubioside increased 6-fold when mixed with iron from 1 to 13 mg.kg −1 but decreased with chlorogenic and gallic acids. Degradation rate of cyanidin 3- O -sambubioside was not affected by polyphenols but increased by 3-fold with increasing iron concentration with a concomitant yield decrease of scission product, protocatechuic acid. Two pathways of degradation of anthocyanins were identified: a major metal-catalyzed oxidation followed by condensation and a minor scission which represents about 10% of degraded anthocyanins. [ABSTRACT FROM AUTHOR]

Degradation parameters of two main anthocyanins from roselle extract ( Hibiscus sabdariffa L.) stored at different temperatures (4–37 °C) over 60 days were determined. Anthocyanins and some of their degradation products were monitored and quantified using HPLC–MS and DAD. Degradation of anthocyanins followed first-order kinetics and reaction rate constants (k values), which were obtained by non-linear regression, showed that the degradation rate of delphinidin 3-O-sambubioside was higher than that of cyanidin 3-O-sambubioside with k values of 9.2·10 −7 s −1 and 8.4·10 −7 s −1 at 37 °C respectively. The temperature dependence of the rate of anthocyanin degradation was modeled by the Arrhenius equation. Degradation of delphinidin 3-O-sambubioside (Ea = 90 kJ mol −1 ) tended to be significantly more sensitive to an increase in temperature than cyanidin 3-O-sambubioside (Ea = 80 kJ mol −1 ). Degradation of these anthocyanins formed scission products (gallic and protocatechuic acids respectively) and was accompanied by an increase in polymeric color index. [ABSTRACT FROM AUTHOR]

The concentration of thermosensitive bioactive compounds remains an important challenge. A gentle integrated process including enzymatic maceration, crossflow microfiltration, diafiltration and centrifugation was applied to watermelon juice to obtain a natural extract enriched with lycopene. Microfiltration was performed using ceramic membranes with different pore diameters (0.2 to 1.4 μm), transmembrane pressures (50 to 200 kPa) and temperatures (50 °C and 60 °C). Using the best operating conditions during microfiltration, the permeate flux was close to 110 L·h − 1 ·m − 2 , and the lycopene concentration increased 11-fold in the retentate. Diafiltration allowed for the purification of lycopene up to 25-fold. Centrifugation enhanced the lycopene concentration up to 4-fold. cis -Isomerization remained low and similar to that of raw juice. This integrated process obtained a natural extract of lycopene that was 41 times more concentrated and 34 times purer than the initial juice, yielding an extract with up to 2% all- trans -lycopene on a dry basis. [ABSTRACT FROM AUTHOR]

Despite the several advantages of microfiltration, applications of this separation technique in fruit juice industries have been challenged by its low economical productivity due to membrane fouling. Although several studies aimed to identify operating conditions (e.g. juice pretreatment, crossflow filtration mode, etc.) to achieve acceptable performances, only few studies focused on the fouling propensity of fruit juices and on the identification of their foulant compounds. The aim of this work was to evaluate the fouling behavior of two orange juices and focused on the identification of relevant size-classes of foulant particles. Lab-scale filtration tests were carried out in conjunction with juice size-fractionation with the aim of quantifying the resistance to filtration of the juices. Based on a resistance-in-series approach, size-cartographies of foulant particles that are juice and membrane-specific were built. These cartographies were provided for two mineral membranes M 1.2 and M 0.2 with different average pore diameters (1.2 and 0.2 μm). M 1.2 results showed that the fouling is mainly external for both juices and due to particles larger than 2 µm. In contrast, results concerning M 0.2 filtration tests showed that four different size-classes of fruit juices compounds are involved in different fouling mechanisms. Moreover, the hydraulic reversibility of the fouling mechanisms was evaluated through the impact of shear rate on the measured resistances. It was seen that the fouling was mainly reversible when M 1.2 was used for both juices filtration while it was not the case when juices were filtered with M 0.2 . This information would be interesting to choose the appropriate strategy in order to enhance the microfiltration of these juices at large scale. Moreover, the proposed size-cartography strategy would greatly satisfy the industrial demand for practical tool to identify the different size-classes of compounds governing the overall membrane fouling. [ABSTRACT FROM AUTHOR]

A better comprehension of the interactions between suspended solids is necessary to optimize the performance and reduce energy requirement during different operations in fruit juice processing (thermal treatment, sedimentation, centrifugation, filtration, spray drying, etc.). In this context, the aim of this study was to propose a rheological approach to get more insight into the energy of cohesion of orange juice suspended solids (SS). The specific energy of cohesion of suspended solids was obtained from rheological measurements in dynamic mode carried out on orange juices fractions with different suspended solids concentrations and size-classes. Results showed that the specific energy of cohesion increased as the SS content increased, independently of the particles size. However, the solid-like behavior of the juice was enhanced by the presence of large particles. The results obtained show that particles network strength and the viscoelastic behavior of juice result of complex interactions between all juice particles. Even if it was demonstrated that these complex interactions depend on the size of the particles, they might depend also on the physicochemical nature of these latter. The knowledge, for the studied fruit juices, of the evolution of their viscoelastic behavior as function of the SS content might be useful to control and optimize the different operations of their transformation chain. [ABSTRACT FROM AUTHOR]

This study was carried out to assess, for the first time, the effect of ohmic heating on the carotenoid profile of two citrus fruit juices: grapefruit and blood orange. Two heat treatments were designed to obtain pasteurization values of 50 and 150 min (Tref = 70 °C and z-value = 10 °C) with ohmic heating as compared to conventional heating. The results showed that xanthophyll losses could reach 70% for epoxyxanthophylls ( cis -violaxanthin and cis -antheraxanthin) and 40% for hydroxyxanthophylls (β-cryptoxanthin, lutein, and zeaxanthin) with conventional heating, but losses were under 30% and 20%, respectively, with ohmic heating. Carotene species (lycopene and β-carotene) were stable regardless of the treatment. No negative non-thermal effects of ohmic heating were shown on carotenoids. Loss simulations of the studied carotenoids showed that the high temperatures reached with ohmic heating during pasteurization could substantially increase the organoleptic and nutritional quality of acid carotenoid-rich juices. Industrial relevance Citrus are the top fruit crops in terms of world trade. This craze for them -particularly orange and grapefruit- is notably due to their high content in organoleptic and nutritional compounds of interest and among them carotenoids. About 50% of the Citrus production is processed in juice. From the growing variety of products, minimal processed juices now have a significant market share. This work assessed for the first time the effect of ohmic heating, a thermal method for stabilizing juices while minimizing the impact on the juice quality, on the carotenoid profiles of blood orange and grapefruit juice. Pasteurization with ohmic heating was proven to be a very good alternative for protecting carotenoids and especially xanthophylls compared to conventional heating. These results will help in designing ohmic heating process parameters for optimizing the overall quality of carotenoid-rich fruit juices. [ABSTRACT FROM AUTHOR]

Cross-flow microfiltration has replaced conventional fining methods for clarifying fruit juices, resulting in the combination of clarification and preservation in one single continuous operation. However the performance of this process is limited by the fouling mechanism during the filtration operation, related to the fruit juice fouling propensity. The aim of this work was to study the possibility of predicting the fruit juices filterability, according to some of their intrinsic characteristics. Therefore, 9 different commercial orange juices were chemically and physicochemically characterized (17 characterization parameters) and laboratory scale filtration tests, in an agitated and pressurized filtration module, were carried out at constant transmembrane pressure (1.5 bar). Fruit juices filterability was evaluated from the permeate flux evolution during the filtration operation. Partial Least Squares (PLS) method was particularly used for the analysis of relationship between the fruit juices filterability and the juice studied characteristics. PLS was initially performed using the whole set of predictor variables. The aim of this first analysis was to highlight the most important juice characteristics among the 17 studied ones; a simplified PLS model was performed using model-wise method and PLS–VIP method as important variable selection procedure. It was possible to predict satisfactorily ( R 2 > 0.9) fruit juices filterability according to only 5 physicochemical characteristics, reflecting the different phases of the studied juices (dry matter, total soluble solids, pH, conductivity, and surface area average diameter). [ABSTRACT FROM AUTHOR]

Highlights: [•] Wild fruit Dialium guineense is consumed in many parts of sub-Saharan Africa. [•] Dialium guineense fruit is a good source of iron, magnesium and copper. [•] 100g sun-dried ripe pulp can cover RDAs for manganese, copper and iron. [•] Contains all essential amino acids. [•] Could be used as ingredient to reduce micronutrient deficiencies. [Copyright &y& Elsevier]

Highlights: [•] Separation of ellagitannins by ultrafiltration (UF) was tested in blackberry juice. [•] Six organic plate and frame membranes (1–150kDa) were used from 0.5 to 3MPa. [•] Retention was 100% for ellagitannins and depended on pressure for anthocyanins. [•] Modeling confirmed interest in UF to purify ellagitannins through diafiltration. [Copyright &y& Elsevier]

Abstract: Solid–liquid extraction of anthocyanins from calyces of Hibiscus sabdariffa L. was studied to evaluate the influence of the operating parameters. Solid-to-solvent ratio and particle size had the main impact on anthocyanin extraction efficiency. Maximum yield of anthocyanins (88%) was obtained at 25°C with the highest solid-to-solvent ratio (1/25). The decrease in the particle size of the calyces from 2cm to 150μm drastically reduced the extraction time. The increase of temperature reduced the extraction time by increasing the diffusion coefficient (3.9×10−11–1.35×10−10 m2 s−1 between 25 and 90°C) but did not modify the extraction yield. A simple extraction model that integrated anthocyanin thermo-degradation kinetic was proposed. A good agreement between the predicted results of the models and experimental data was demonstrated. From a solid-to-solvent ratio of 1/5, an extraction yield of 63% and an anthocyanin concentration of 0.3gL−1 could be obtained in less than 10min. [Copyright &y& Elsevier]

Abstract: Ten nanofiltration flat-sheet membranes and eight tight ultrafiltration membranes with nominal MWCOs ranging from 0.2 to 150kDa were tested to concentrate anthocyanin extract from roselle. A pilot system was used, which featured a membrane cell with an effective area of 0.0155m2. Permeate fluxes were recorded for transmembrane pressures between 0.5 and 3.0MPa, while keeping all other operating conditions constant (volumetric reduction ratio 1, 35°C). Retention values of total soluble solids, acidity and anthocyanins increased with transmembrane pressure. With similar permeate fluxes at average transmembrane pressure, retention of anthocyanins is significantly higher for nanofiltration membranes than for ultrafiltration membranes. A membrane was then selected for an industrial trial on the basis of its flux, retention of compounds of interest and energy consumption per liter of permeate. The trial using a 2.5-m2 filtration surface, could concentrate roselle extract from 4 to 25g total soluble solids per 100g, with 100% retention of anthocyanins. No significant damages were observed when comparing concentrate quality with the initial roselle extract. [Copyright &y& Elsevier]

Abstract: In this study, roselle extract was cold sterilized by crossflow microfiltration. At laboratory scale the optimal operating conditions at volumetric reduction ratio (VRR) 1 cannot be generalized when VRR is greater than 1. Indeed, at VRR 1 the optimal transmembrane pressure was 2.5bar with a permeate flux of 185Lh−1 m−2, while at VRR 20 optimal pressure was 3.7bar with a permeate flux of 95Lh−1 m−2. A simple model that allowed to represent the effect of VRR and transmembrane pressure on the permeate flux was adjusted with the experiments done at laboratory scale. This model used to predict the permeate flux using a semi-industrial pilot scale equipment gave a good match between the experimental and calculated performances. Permeate was collected aseptically and stored at 4, 20 and 37°C for 90days. A roselle extract storage at 4 and 20°C was appropriate for consumption after a 3month shelf life. [Copyright &y& Elsevier]