Lycopene and β-Carotene Extraction from Tomato Processing Waste Using Supercritical CO2

Optimization of the Parameters Influencing the Antioxidant Activity and Concentration of Carotenoids Extracted from Pumpkin Peel Using a Central Composite Design

It has been discovered that the peel of a pumpkin (Cucurbita maxima), regarded as a waste product of pumpkin processing, has significant amounts of carotenoids and other antioxidants. This study aims to identify the most effective extraction parameters for an ultrasonic-assisted extraction method to extract the total carotenoids (TCs) and assess the antioxidant activity (AA) of pumpkin peel. To determine the effects of the extraction time, temperature, and material-to-solvent ratio on the recovery of TCs and AA, a response surface methodology utilizing the central composite design (CCD) was used. The extraction temperature (6.25-98.75 °C), extraction duration (13.98-128.98 min), and solvent ratio (0.23-50.23 mL) were the variables studied in the coded form of the experimental plan. The carotenoid concentration varied from 0.53 to 1.06 mg/g DW, while the AA varied from 0.34 to 7.28 µM TE/g DW. The findings indicated that the optimal extraction parameters were an 80 °C temperature, a 10 mL solvent ratio, and a 100 min extraction time. The study confirmed that the optimum extraction conditions resulted in an experimental TC yield of 0.97 mg/g DW and an AA of 7.25 µM TE/g DW. Overall, it should be emphasized that the extraction process can be enhanced by setting the operating factors to maximize the model responses.

Influence of particle size in supercritical carbon dioxide extraction of roselle (Hibiscus sabdariffa) on bioactive compound recovery, extraction rate, diffusivity, and solubility

The purpose of this work was to establish the best particle size for recovering high yields of total phenolic compounds (TPC), total anthocyanin compounds(TAC) and total flavonoid compounds (TFC) from roselle (Hibiscus sabdariffa) by applying supercritical carbon dioxide (ScCO₂). The extraction rate, diffusivity and solubility of yield in ScCO₂ were also studied and calculated utilizing models. Pressure (10 and 30 MPa), temperature (40 and 60 °C), and particle size (250 µm < dp < 355 µm, 355 µm < dp < 425 µm and 425 µm < dp < 500 µm) were employed as variables in this experiment. The greatest recovery was 11.96% yield, 7.16 mg/100 g TAC, 42.93 mg/100 g TPC and 239.36 mg/100 g TFC under the conditions of 30 MPA, 40 °C and 250 µm < dp < 355 µm, respectively. The extraction rate of supercritical carbon dioxide in roselle extraction ranged from 5.19 E-03 to 1.35 E-03 mg/s fitted using the Esquivel model. The diffusivity coefficient of ScCO₂ ranged from 2.17E-12 to 3.72E-11 mg/s², as fitted by a single sphere model. The greatest solubility of global yield, TAC, TPC and TFC in ScCO₂ was 1.50 g/L, 0.3 mg/L, 1.69 mg/L and 9.97 mg/L, respectively, with a particle size of 250 µm < dp < 355 µm. The smaller particle size of roselle provides the maximum bioactive compound recovery and solubility. Furthermore, the diffusivity and extraction of ScCO₂ are increased by decreasing the particle size. Therefore, a smaller particle size is appropriate for roselle extraction by ScCO₂ based on the experimental and modelling data.

Waste and by-products as sources of lycopene, phytoene, and phytofluene - Integrative review with bibliometric analysis

Food loss and waste are severe social, economic, and environmental issues. An example is the incorrect handling of waste or by-products used to obtain bioactive compounds, such as carotenoids. This review aimed to present a comprehensive overview of research on lycopene, phytoene, and phytofluene obtained from waste and by-products. In this study, an integrative literature approach was coupled with bibliometric analysis to provide a broad perspective of the topic. PRISMA guidelines were used to search studies in the Web of Science database systematically. Articles were included if (1) employed waste or by-products to obtain lycopene, phytoene, and phytofluene or (2) performed applications of the carotenoids previously extracted from waste sources. Two hundred and four articles were included in the study, and the prevalent theme was research on the recovery of lycopene from tomato processing. However, the scarcity of studies on colorless carotenoids (phytoene and phytofluene) was evidenced, although these are generally associated with lycopene. Different technologies were used to extract lycopene from plant matrices, with a clear current trend toward choosing environmentally friendly alternatives. Microbial production of carotenoids from various wastes is a highly competitive alternative to conventional processes. The results described here can guide future forays into the subject, especially regarding research on phytoene and phytofluene, potential and untapped sources of carotenoids from waste and by-products, and in choosing more efficient, safe, and environmentally sustainable extraction protocols.

Current Technologies and Uses for Fruit and Vegetable Wastes in a Sustainable System: A Review

The fruit and vegetable industry produces millions of tons of residues, which can cause large economic losses. Fruit and vegetable wastes and by-products contain a large number of bioactive substances with functional ingredients that have antioxidant, antibacterial, and other properties. Current technologies can utilize fruit and vegetable waste and by-products as ingredients, food bioactive compounds, and biofuels. Traditional and commercial utilization in the food industry includes such technologies as microwave-assisted extraction (MAE), supercritical fluid extraction (SFE), ultrasonic-assisted extraction (UAE), and high hydrostatic pressure technique (HHP). Biorefinery methods for converting fruit and vegetable wastes into biofuels, such as anaerobic digestion (AD), fermentation, incineration, pyrolysis and gasification, and hydrothermal carbonization, are described. This study provides strategies for the processing of fruit and vegetable wastes using eco-friendly technologies and lays a foundation for the utilization of fruit and vegetable loss/waste and by-products in a sustainable system.

High-temperature Supercritical CO2 Extraction of Lycopene from Tomato Powder for Enhancing Z-Isomerization and Recovery of Lycopene

This study aimed to investigate the effect of extraction conditions (temperature, pressure, and entrainer content) on the total Z-isomer ratio and recovery of lycopene in the extracts obtained after supercritical CO₂ (SC-CO₂) extraction of lycopene from tomato powder, with a particular focus on high-temperature conditions (≥ 80°C). The results showed that high-temperature SC-CO₂ extraction promoted the thermal isomerization of lycopene in a temperature-dependent manner up to 120℃. For example, when lycopene extraction was carried out at 80, 100, 120, and 140°C and a pressure of 30 MPa with an entrainer, ethanol, for 180 min, the total Z-isomer ratios obtained were 25.0, 57.2, 67.2, and 67.0%, respectively. The entrainer content also affected the Z-isomer ratio of lycopene, but the pressure had little effect. Interestingly, when SC-CO₂ extraction was performed under high-temperature conditions (≥ 100°C), the extraction efficiency of lycopene was dramatically improved, e.g., when lycopene was extracted at 80, 100, 120, and 140°C under the same other conditions as above, the recovery rates of lycopene were 4.6, 28.5, 79.9, 84.8%, respectively. In general, SC-CO₂ extraction of fat-soluble components is performed at temperatures in the range of 40-80°C because the SC-CO₂ density decreases with increasing temperature, and thus, their solubility (extraction efficiency) decreases. However, our results showed that the lycopene recovery increased in a temperature-dependent manner, which might be due to the solubility enhancement associated with thermal Z-isomerization of lycopene (i.e., lycopene Z-isomers have greater solubility than the naturally occurring all-E-isomer). The high-temperature SC-CO₂ extraction of lycopene from tomato materials not only enhances the Z-isomer ratio of lycopene in the resulting extracts but also improves lycopene recovery. This new finding will greatly contribute to the value addition and cost reduction of natural lycopene sources obtained by SC-CO₂ extraction.

Influence of Ripening Stage on Quality Parameters of Five Traditional Tomato Varieties Grown under Organic Conditions

Consumers demand traditional, tasty tomatoes in contrast to new hybrid cultivars that have poor sensory characteristics. Some physicochemical parameters (total soluble solids, pH, titratable acidity, color and firmness), functional properties (vitamin C, lycopene, β-carotene and total antioxidant activity) and sensory characteristics of five traditional tomato varieties (T1-T5) in three ripening stages, grown under organic conditions, were evaluated. These were compared to the commercial hybrid ‘Baghera’, grown in the same conditions. Firmness of all varieties declined and the color parameters L* and H* decreased, whereas a* and a*/b* increased progressively with ripening. Lycopene also increased with ripening in all varieties, with the highest content being 132.64 mg kg−1 fw for T4. All traditional tomato varieties were richer in lycopene than commercial ones in the two last ripening stages. Vitamin C content ranged widely between 27.33 and 267.27 mg kg−1 fw. Among the traditional varieties, T2 (BGV003524) stood out due to its highest total soluble solids and vitamin C contents, total antioxidant activity, and H* and a*/b*; this variety was also the most appreciated by panelists. These traditional varieties could be an alternative to commercial cultivars, as they have good quality characteristics and can satisfy consumer demand for organic produce.

Bioactivity and Bioaccessibility of Bioactive Compounds in Gastrointestinal Digestion of Tomato Bagasse Extracts

A nutrient-rich diet is a key to improving the chemical signals, such as antioxidants, which modulate pathogens’ resistance in the gut and prevent diseases. A current industrial problem is the generation of undervalued by-products, such as tomato bagasse, which are rich in bioactive compounds and of commercial interest (carotenoids and phenolic compounds). This work analyzed the effect of gastrointestinal digestion on the bioactivity and bioaccessibility of carotenoids and phenolic compounds from tomato bagasse extracts. Thus, the extraction by ohmic heating (OH) technology was compared with conventional (organic solvents). The results showed that the main phenolic compounds identified by UPLC-qTOF-MS were p-coumaric acid, naringenin, and luteolin. A higher recovery index for total phenolic compounds throughout the gastrointestinal digestion was observed for OH while for carotenoids, a strong reduction after stomach conditions was observed for both extracts. Furthermore, colon-available fraction exhibited a prebiotic effect upon different Bifidobacterium and Lactobacillus, but a strain-dependent and more accentuated effect on OH. Thus, the extraction technology highly influenced bioaccessibility, with OH demonstrating a positive impact on the recovery of bioactive compounds and related health benefits, such as antioxidant, anti-hypertensive, prebiotic, and anti-inflammatory properties. Of these properties, the last is demonstrated here for the first time.

High-Pressure Technologies for the Recovery of Bioactive Molecules from Agro-Industrial Waste

Large amounts of food waste are produced each year. These residues require appropriate management to reduce their environmental impact and, at the same time, economic loss. However, this waste is still rich in compounds (e.g., colorants, antioxidants, polyphenols, fatty acids, vitamins, and proteins) that can find potential applications in food, pharmaceutical, and cosmetic industries. Conventional extraction techniques suffer some drawbacks when applied to the exploitation of food residues, including large amounts of polluting solvents, increased time of extraction, possible degradation of the active molecules during extraction, low yields, and reduced extraction selectivity. For these reasons, advanced extraction techniques have emerged in order to obtain efficient residue exploitation using more sustainable processes. In particular, performing extraction under high-pressure conditions, such as supercritical fluids and pressurized liquid extraction, offers several advantages for the extraction of bioactive molecules. These include the reduced use of toxic solvents, reduced extraction time, high selectivity, and the possibility of being applied in combination in a cascade of progressive extractions. In this review, an overview of high-pressure extraction techniques related to the recovery of high added value compounds from waste generated in food industries is presented and a critical discussion of the advantages and disadvantages of each process is reported. Furthermore, the possibility of combined multi-stage extractions, as well as economic and environmental aspects, are discussed in order to provide a complete overview of the topic.

Challenges and solutions of extracting value-added ingredients from fruit and vegetable by-products: a review

Every year, huge amounts of fruit and vegetable by-products in the food processing factories are produced. These by-products have great potential to be used for different targets especially the extraction of value-added ingredients. The target of this study is to review the challenges of extraction of value-added ingredients from fruit and vegetable by-products on the industrial scale and to describe current trends in solving these problems. In addition, some strategies such as multi-component extraction as well as application of fermentation before or after the extraction process, and production of biofuel, organic fertilizers, animal feeds, etc. on final residues after extraction of value-added ingredients are discussed in this review paper. In fact, simultaneous extraction of different value-added ingredients from fruit and vegetable by-products can increase the extraction efficiency and reduce the cost of value-added ingredients as well as the final volume of these by-products. After extraction of value-added ingredients, the residues can be used to produce biofuels, or they can be used to produce organic fertilizers, animal feeds, etc. Therefore, the application of several appropriate strategies to treat the fruit and vegetable by-products can increase their application, protect the environment, and improve the food economy.

Recovery of Carotenoids from Tomato Pomace Using a Hydrofluorocarbon Solvent in Sub-Critical Conditions

The enrichment of oils with nutraceutical bioactive phytomolecules allows the achievement of functional oil-based products of great interest in the food, pharmaceutical, and cosmetic fields. Carotenoids, such as lycopene and β-carotene, are available at a high concentration in tomatoes and tomato waste products, as peels, seeds, and pulp; their recovery is recently attracting growing interest and economic importance in the food industry, and also in consideration of the huge amount of industrial waste produced. The aim of this work is to study the production of an oil functionalized with carotenoids from tomato peels. The extractions were carried out using an innovative process based on the use of commercial Norflurane as solvent in subcritical conditions. Extraction trials were performed on dried tomato peels, with the addition of tomato seeds or wheat germ flour as sources of oily co-solvents, capable of also preserving the biological characteristics of the carotenoids extracted. Although lycopene solubility in Norflurane is quite low, the solvent recirculation and regeneration were allowed to reach a concentration in the oily extracts of approximately 0.3 mg/goil after 2 h of the process. The enrichment in β-carotene was more pronounced, and concentrations of 0.733 mg/goil and 0.952 mg/goil were observed in wheat germ and tomato seed oils, respectively. The results obtained in this study were compared with those obtained by traditional and supercritical CO2 extraction methods.

Valorization of Tomato Residues by Supercritical Fluid Extraction

Tomato processing leads to the production of considerable amounts of residues, mainly in the form of tomato skins, seeds and vascular tissues, which still contain bioactive molecules of interest for food, pharmaceutical and nutraceutical industries. These include carotenoids, such as lycopene and β-carotene, tocopherols and sitosterols, among others. Supercritical fluid extraction is well positioned for the valorization of tomato residues prior to disposal, because it remains an environmentally safe extraction process, especially when using carbon dioxide as the solvent. In this article, we provide an extensive literature overview of the research on the supercritical fluid extraction of tomato residues. We start by identifying the most relevant extractables present in tomatoes (e.g., lycopene) and their main bioactivities. Then, the main aspects affecting the extraction performance are covered, starting with the differences between tomato matrixes (e.g., seeds, skins and pulp) and possible pretreatments to enhance extraction (e.g., milling, drying and enzymatic digestion). Finally, the effects of extraction conditions, such as pressure, temperature, cosolvent, flow rate and time, are discussed.

Value-Added Metabolites from Agricultural Waste and Application of Green Extraction Techniques

The agricultural sector generates approximately 1300 million tonnes of waste annually, where up to 50% comprising of raw material are discarded without treatment. Economic development and rising living standards have increased the quantity and complexity of waste generated resulting in environmental, health and economic issues. This calls for a greener waste management system such as valorization or recovery of waste into products. For successful implementation, social acceptance is an essential component with involvement of all local stakeholders including community to learn and understand the process and objective of the implementation. The agricultural waste product manufacturing industry is expected to increase with the growing demand for organic food. Thus, proper livestock and crop waste management is vital for environmental protection. It will be essential to successfully convert waste into a sustainable product that is reusable and circulated in the system in line with the green concept of circular economy. This review identifies the commercially produced crops by-product that have been considered for valorization and implemented green extraction for recovery. We highlight the importance of social acceptance and the economic value to agricultural waste recycling. Successful implementation of these technologies will overcome current waste management problems, reduce environmental impacts of landfills, and sustainability issue for farm owners.

Extraction of Carotenoids from Pumpkin Peel and Pulp: Comparison between Innovative Green Extraction Technologies (Ultrasonic and Microwave-Assisted Extractions Using Corn Oil)

Natural pigments improve aesthetic value as well as antioxidant potential of a food product. This study was designed to determine the effects of green extraction techniques on carotenoids, polyphenols and antioxidant activities of pulp and peel of two varieties of pumpkin (Cucurbita maxima). Innovative green extractions (IGE; Ultrasound and Microwave-Assisted Extractions) synergised with corn oil (used as green solvent) were compared with conventional extraction (CE; hexane/isopropyl alcohol; 60:40, v/v). Results showed total carotenoids to be almost double on employing IGE (PM2-UAE-peel = 38.03 ± 4.21; PM4-UAE-peel = 33.78 ± 1.76 µg/g) when compared to conventional extraction (PM2-CE-peel = 19.21 ± 4.39; PM4-CE-peel = 16.21 ± 2.52 µg/g). Polyphenolic contents ranged between 510.69 ± 5.50 and 588.68 ± 7.26 mg GAE/100 g of extract in IGE, compared with conventional extracts (269.50 ± 2.17 to 318.46 ± 6.60 mg GAE/100 g) and percent inhibition of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) ranging between 88.32 ± 1.51 and 93.53 ± 0.30% in IGE when compared with conventional extraction (50.61 ± 1.44 to 57.79 ± 2.09%). Further, oxidative stability of carotenoids extracts from IGE (protection factor = 1.59 ± 0.01 to 1.81 ± 0.05) were found to be significantly higher (p < 0.05) than conventional extracts. Based on results, this study supports the use of innovative green extraction techniques to obtain bioactive pigments like carotenoids. It is anticipated that results generated will find potential applications in food, pharmaceutical and cosmetic industries.

A comprehensive review on carotenoids in foods and feeds: status quo, applications, patents, and research needs

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.

Artificial neural network model in predicting the quality of fresh tomato genotypes

Sensory analysis is the best mean to precisely describe the eating quality of fresh foods. However, it is expensive and time-consuming method which cannot be used for measuring quality properties in real time. The aim of this paper was to contribute to the study of the relationship between sensory and instrumental data, and to define a proper model for predicting sensory properties of fresh tomato through the determination of the physicochemical properties. Principal Component Analysis (PCA) was applied to the experimental data to characterize and differentiate among the observed genotypes, explaining 73.52% of the total variance, using the first three principal components. Artificial neural network (ANN) model was used for the prediction of sensory properties based on the results obtained by basic chemical and instrumental determinations. The developed ANN model predicts the sensory properties with high adequacy, with the overall coefficient of determination of 0.859.

A new type of tomato puree with high content of bioactive compounds from 100% whole fruit

In this work, a new type of tomato puree was obtained from the whole fruit including seeds and skins without any waste. Currently, the food industry aims to develop products that both bring benefits to consumer health and are ecosustainable. Several efforts in fact have been carried out to revalue tomato by-products, such as seeds and skins, for human use. The physicochemical properties of the whole tomato puree immediately after production and after 6 months of storage were investigated and compared to the properties of a traditional tomato puree. Two tomato varieties were used in this study: Villa Literno and Piccadilly. pH, dry weight, water activity, titratable acidity, reducing sugars, soluble solid, lycopene, polyphenol, and volatile organic compound contents were evaluated. Tomato puree obtained from whole fruits mainly showed higher lycopene (90 to 150 mg/kg), flavonoid (39 to 41 mg/kg), and aldehyde (in particular hexanal) contents and a greater stability over time compared to those of the traditional puree. The proposed process allowed to obtain a tomato puree with a higher content of bioactive compounds, producing no waste. PRACTICAL APPLICATION: In this study, we proposed a new type of tomato puree made from the whole fruit. The whole tomato puree is richer in phenolic compounds and volatile organic compounds than the traditional puree that is made by removing skins and seeds. It can be an interesting product for the food industries because it is a source of bioactive compounds and reduces to zero the amount of waste.

Tomato as Potential Source of Natural Additives for Meat Industry. A Review

Tomato industry produces huge amounts of by-products that represent an environmental and economic problem. However, these by-products contain multiple bioactive compounds, which would make them a renewable source for obtaining natural antioxidants and colourants (carotenoids). This is in line with the preferences of the current consumer who demands more natural and healthy products. However, the lipophilic character of carotenoids means that their extraction must be carried out using toxic organic solvents. To overcome environmental and health problems of organic solvents, the application of supercritical fluid extraction (SFE) for the extraction of lipophilic compounds such as lycopene was used successfully, achieving yields similar to those obtained with conventional techniques. Nonetheless, the extraction conditions must be carefully selected, to obtain high yields and at the same time maintain a high antioxidant capacity. On the other hand, the use of tomato and tomato extracts as natural additives in meat products are reduced in comparison with other natural antioxidant/colourant extracts. However, different researches conclude that the use of tomato improved nutritional quality, reduced lipid oxidation and increased stability during the shelf-life period of meat products, while retaining or increasing sensory properties and overall acceptability, which converts tomato by-products into a promising source of natural additives.

Natural Dyes and Their Derivatives Integrated into Organic Solar Cells

Natural photosynthetic systems contain several dyes such as carotenoids or chlorophylls which are adequately arranged to produce efficient photoinduced charge separation and electron transfer. Several research groups have attempted integrating these natural dyes and photosynthetic systems into functional organic solar cells (OSCs) producing power conversion efficiencies (PCEs) up to 0.99%. The studies presented in this short review emphasize that functionalization of natural dyes can considerably improve their PCEs. For instance, chlorophyll derivatives can yield PCEs up to 2.1%, and copolymers produced with isoindigo as an electron-deficient unit generate high PCEs up to 8%, respectively, when combined with fullerene C70 based electron acceptors in the OSC active layers. An alternative approach for natural dye integration into OSC architectures is to place these light-harvesting antennas at the interface between the active layer and the charge collection layers in these low-cost photovoltaic devices. This strategy produces large PCE increases up to 35% with respect to OSCs prepared without the interlayer. When light-harvesting systems are combined with silver nanoprisms as interlayers, additional localized surface plasmon resonance effects result in high-performance OSCs that integrate natural photosynthetic systems and demonstrate a PCE over the milestone value of 10%.

Effect of solvent addition sequence on lycopene extraction efficiency from membrane neutralized caustic peeled tomato waste

Lycopene is a high value nutraceutical and its isolation from waste streams is often desirable to maximize profits. This research investigated solvent addition order and composition on lycopene extraction efficiency from a commercial tomato waste stream (pH 12.5, solids ∼5%) that was neutralized using membrane filtration. Constant volume dilution (CVD) was used to desalinate the caustic salt to neutralize the waste. Acetone, ethanol and hexane were used as direct or blended additions. Extraction efficiency was defined as the amount of lycopene extracted divided by the total lycopene in the sample. The CVD operation reduced the active alkali of the waste from 0.66 to <0.01M and the moisture content of the pulp increased from 93% to 97% (wet basis), showing the removal of caustic salts from the waste. Extraction efficiency varied from 32.5% to 94.5%. This study demonstrates a lab scale feasibility to extract lycopene efficiently from tomato processing byproducts.

Bread enriched in lycopene and other bioactive compounds by addition of dry tomato waste

The tomato processing industry generates high amounts of waste, mainly tomato skins and seeds, which create environmental problems. These residues are attractive sources of valuable bioactive components and pigments. A relatively simple recovery technology could consist of production of powders to be directly incorporated into foods. Tomato waste coming from a Romanian tomato processing unit were analyzed for the content of several bioactive compounds like ascorbic acid, β-carotene, lycopene, total phenolics, mineral and trace elements. In addition, its antioxidant capacity was assayed. Results revealed that tomato waste (skins and seeds) could be successfully utilized as functional ingredient for the formulation of antioxidant rich functional foods. Dry tomato processing waste were used to supplement wheat flour at 6 and 10 % levels (w/w flour basis) and the effects on the bread's physicochemical, baking and sensorial characteristics were studied. The following changes were observed: increase in moisture content, titratable acidity and bread crumb elasticity, reduction in specific volume and bread crumb porosity. The addition of dry tomato waste at 6 % resulted in bread with good sensory characteristics and overall acceptability but as the amount of dry tomato waste increased to 10 %, bread was less acceptable.

Ultrasound assisted extraction of lycopene from tomato processing wastes

Tomato paste processing wastes, an important by-product of the paste industry, is rich in potentially health-promoting compounds such as lycopene. In this study, extraction yield of lycopene from tomato paste processing wastes by application of ultrasound assisted extraction (UAE) was compared with conventional organic solvent extraction (COSE) method. BHT (butylated hydroxytoluene) 0.05 % (w/v) added hexane:acetone:ethanol (2:1:1) mixture was used as solvent. Three different solvent solid ratios; 50:1, 35:1 and 20:1, (v/w) were used in both COSE and UAE. COSE experiments were performed at 20 °C, 40 °C and 60 °C for 10, 20, 30 and 40 min. 50, 65 and 90 W of ultrasonic power were applied in UAE for 1, 2, 5, 10, 15, 20 and 30 min. Lycopene contents of the samples were determined by spectrophotometric method. The effects of different factors, including the temperature, solvent solid ratio and ultrasonic power on lycopene yield were investigated. It was determined that the most efficient application for COSE was extracting samples by 50:1 solvent solid ratio at 60 °C for 40 min run, for UAE, 35:1 (v/w) solvent solid ratio, 90 W ultrasonic power for 30 min run. It was showed that UAE of lycopene requires less time, lower temperature and lower solvent than COSE.

High impact biowastes from South European agro-industries as feedstock for second-generation biorefineries

Availability of bio-based chemicals, materials and energy at reasonable cost will be one of the forthcoming issues for the EU economy. In particular, the development of technologies making use of alternative resources to fossil fuels is encouraged by the current European research and innovation strategy to face the societal challenge of natural resource scarcity, fossil resource dependence and sustainable economic growth. In this respect, second- generation biorefineries, i.e. biorefineries fed with biowastes, appear to be good candidates to substitute and replace the present downstream processing scheme. Contrary to first-generation biorefineries, which make use of dedicated crops or primary cultivations to achieve such a goal, the former employ agricultural, industrial, zootechnical, fishery and forestry biowastes as the main feedstock. This leaves aside any ethical and social issue generated by first-generation approaches, and concomitantly prevents environmental and economical issues associated with the disposal of the aforementioned leftovers. Unfortunately, to date, a comprehensive and updated mapping of the availability and potential use of bioresources for second-generation biorefineries in Europe is missing. This is a lack that severely limits R&D and industrial applications in the sector. On the other hand, attempts at valorizing the most diverse biowastes dates back to the nineteenth century and plenty of information in the literature on their sustainable exploitation is available. However, the large majority of these investigations have been focused on single fractions of biowastes or single steps of biowaste processing, preventing considerations on an integrated and modular (cascade) approach for the whole valorization of organic leftovers. This review aims at addressing these issues by gathering recent data on (a) some of the main high-impact biowastes located in Europe and in particular in its Southern part, and (b) the bio-based chemicals, materials and fuels that can be produced from such residues. In particular, we focused on those key compounds referred to as "chemical platforms", which have been indicated as fundamental to generate the large majority of the industrially relevant goods to date.