Tomato By-products Research Articles

Processing tomato by-products re-use, secondary raw material for tomato product with new functionality

Processing tomato by-products re-use, secondary raw material for tomato product with new functionality

Responses of laying hens to the simultaneous dietary supplementation with flaxseed and dried tomato by-products

Apple (AP), blueberry (BP), red raspberry (RP), and cranberry pomace (CP), were evaluated for their physicochemical and functional properties and bioactive compounds (i.e. dietary fibers and phenolics) as potential functional food ingredients. Bound phenolics in AP, BP, and CP could be liberated through simulated gastrointestinal digestion (SGD). Among all tested fruit pomace (FP), RP contained the highest total phenolic content based on both chemical extraction and SGD. AP contained the highest soluble dietary fiber obtained from AOAC method and SGD, while it presented the lowest insoluble dietary fiber in comparison with BP, RP, and CP. Total dietary fiber content of RP and CP from SGD was significantly (P < 0.05) higher than that from AOAC method. AP exhibited a high water-holding capacity (9.27 g water/g dry weight (DW)) and swelling ability (6.51 mL/g DW), while BP and CP showed high oil-adsorption capacity (1.96 g oil/g DW and 1.97 g oil/g DW, respectively). The differences in the functional properties of the tested FP could be due to their distinguished fiber compositions and structures. This study demonstrated the potential of using FP as fiber-rich and antioxidant functional ingredient that can be selectively utilized in various food applications.

Phenolic composition of tomato varieties and an industrial tomato by-product: free, conjugated and bound phenolics and antioxidant activity

The aim of this study was to isolate, identify and quantify soluble free phenolics, conjugated acid-hydrolysable phenolics (AHP) and alkaline-hydrolysable phenolics, and bound phenolics (BP) fractions from two tomato varieties (saladette and grape) and an industrial tomato by-product, as well as, to determine their antioxidant capacity. Phenolic composition was determined using Folin-Ciocalteu's method and HPLC-DAD. AHP were predominant in grape and saladette tomato extracts (91.47 ± 17.28mg gallic acid equivalents (GAE) per g dry extract (DE) and 57.41 ± 8.80mg GAE per g DE, respectively), while BP form was predominant in tomato by-product (51.30 ± 10.91 GAE per g DE). AHP extract of grape tomato presented the highest antioxidant capacity by DPPH assay (252.35 ± 42.55 μmol trolox equiv (TE) per g DE). In the case of ORAC assay, AHP fractions from both grape (1005.19 ± 138.52μmol TE per g DE) and saladette tomatoes (804.16 ± 131.45μmol TE per g DE), and BP fraction from by-product (852.40 ± 71.46μmol TE per g DE) showed the highest ORAC values. Caffeic acid was the most abundant phenolic acid and it was found mainly in its conjugated forms. Naringenin was the most abundant flavonoid and it was mainly detected in bound form. Our analysis allowed a better characterization of phenolic compounds in whole tomato and by-product, remarking the importance of the fractionation. The valorization of the industrial tomato by-product, through the use of its different fractions of phenolic antioxidant compounds, could generate additional income to the tomato industry and reduce the waste disposal problem.

Influence of Tomato Powder as Dietary Supplementation on Some Physiological, Biochemical and Histological Parameters in New Zealand White Growing Rabbits

Tomato and tomato-by products contain some phytochemicals that may have health benefits and are important sources of many nutrients. Therefore, this study aimed to investigate the effect of two different concentrations (1 and 2%) of tomato powder (TP) in diet of New Zealand white growing rabbits on some physiological, biochemical and histological parameters. Thirty unsexed New Zealand white growing rabbits (42 days old) were randomly assigned into 3 groups (10 rabbits each). The first group served as control (no additives). The second and the third groups were fed diets containing 1 and 2% tomato powder (TP), respectively, for 8 weeks. Results revealed that, no significant differences were observed in the absolute weights of some organs (kidney and thymus) and serum electrolyte concentrations (Ca, P, K, Na) between TP treated groups and control. Dietary 1 and 2% TP supplementation induced alterations in serum biochemical parameters. Serum albumin (g/dl), A/G ratio urea, uric acid and creatinine concentrations were significantly (p < 0.05) decreased by TP administration (1 and 2%), whereas globulin concentration (g/dl) was significantly (p < 0.05) increased compared to control group. Furthermore, no histopathological alterations were recorded in liver and kidney of TP treated groups. In conclusion, TP can be safely used in New Zealand white growing rabbits diet as natural growth enhancer.

Agro-industrial tomato by-products and extraction of functional food ingredients

Agro-industrial tomato by-products and extraction of functional food ingredients

Peptidomic analysis of antioxidant and ACE-inhibitory peptides obtained from tomato waste proteins fermented using Bacillus subtilis

In this study, tomato seeds were obtained as by-products and submitted to fermentation with the proteolytic strain Bacillus subtilis A14h. The resulting peptide mixture was fractionated and purified through different chromatographic steps. Fractions were assayed for antioxidant and angiotensin converting enzyme (ACE)-inhibitory activities and peptides were identified by using nano-liquid chromatography coupled to mass spectrometry in tandem (nLC-MS/MS). Most of the identified peptides were smaller than 1000 Da and had different aromatic and hydrophobic amino acid residues. Their sequences were novel but some of them showed active domains previously reported in other bioactive peptides. The hexapeptide DGVVYY showed an IC50 value of 2 µM in angiotensin-I converting enzyme (ACE-I) inhibitory activity, whereas the pentapeptide GQVPP displayed a 97% of DPPH activity at 0.4 mM. The results revealed that B. subtilis fermentation of tomato by-products could be a good strategy for obtaining added-value peptides that might be used as an ingredient in functional foods and nutraceuticals.

Consumer acceptance and willingness to pay for a fresh fish-burger: A choice experiment

This study investigates consumers’ acceptance and willingness to pay for a fish burger produced with fresh Ombrina fish, tomato by-product and enriched with extra-virgin olive oil. The analysis is based on a hypothetical choice experiment study on participants’ preferences that was conducted in a lab on a random sample of consumers in Italy. The results show a positive attitude towards the burger that contain tomato by-product. Participants are, in fact, willing to pay up to 0.57 euro and 0.37 euro extra for the “Environment” and “Health” attributes, respectively. It also appears that psychometric variables in association with socio-demographic, cognitive and attitudinal factors play a role in consumers’ purchase decisions.At sensory level, 43% of participants chose the burger that contains tomato peel flour, attributing an average value of 6.75 to Burger B and 8.03 to burger C according to a scale 1 to 10.

Obtaining enriched fried tomato sauce using tomato byproducts

The industrial processing of tomato concentrate produces roughly 4% of byproducts, in the form of skins and seeds, which is typically collected by specialist companies for the production of animal feed, or subjected to chemical extraction processes to obtain lycopene compounds. The health benefits of lycopene have been well documented in terms of antioxidant properties and dietary fiber. The objective of this study was the repurposing of these byproducts from the industrial tomato industry through the creation of new tomato sauces with the addition of an intermediary food product (IFP), in the form of a food texturizer, while also improving dietary fiber and lycopene content. For this purpose, a series of trials was undertaken with the aim of producing fried tomato to which the IFPs had been added as a partial or total replacement for starch as a texturizing agent. After sensorial trials, it was determined that the most suitable IFPs for the replacement of starch were IFPs using a HOT tomato concentrate with 5 and 10% fresh skins and seeds, and IFPs prepared from a mixture of fresh juice, seeds and skins in ratios of 20 and 30%, which were subsequently concentrated. All of the fried tomato sauces that were produced were deemed to be acceptable to the sensorial tasting panels. For this reason, the use of IFPs obtained from tomato byproducts and subsequently reused for the production of sauces can be considered as an ingredient that acts as an effective texturizing agent, improving both dietary fiber and lycopene values.

A Simplified Method to Estimate Sc-CO2 Extraction of Bioactive Compounds from Different Matrices: Chili Pepper vs. Tomato By-Products

In the last few decades, the search for bioactive compounds or “target molecules” from natural sources or their by-products has become the most important application of the supercritical fluid extraction (SFE) process. In this context, the present research had two main objectives: (i) to verify the effectiveness of a two-step SFE process (namely, a preliminary Sc-CO2 extraction of carotenoids followed by the recovery of polyphenols by ethanol coupled with Sc-CO2) in order to obtain bioactive extracts from two widespread different matrices (chili pepper and tomato by-products), and (ii) to test the validity of the mathematical model proposed to describe the kinetics of SFE of carotenoids from different matrices, the knowledge of which is required also for the definition of the role played in the extraction process by the characteristics of the sample matrix. On the basis of the results obtained, it was possible to introduce a simplified kinetic model that was able to describe the time evolution of the extraction of bioactive compounds (mainly carotenoids and phenols) from different substrates. In particular, while both chili pepper and tomato were confirmed to be good sources of bioactive antioxidant compounds, the extraction process from chili pepper was faster than from tomato under identical operating conditions.

The cis-lycopene isomers composition in supercritical CO2 extracted tomato by-products

The use of concentrated carotenoid extracts from red-ripe tomato by-products in traditional foods can improve the functional properties of the product while increasing the efficiency of industrial red-ripe tomatoes processing. In red tomatoes, lycopene is almost exclusively found in the all-trans-form, but during processing lycopene can undergo isomerisation to cis-lycopene isomers. The cis-lycopene isomers offer potentially better health benefits than the trans-lycopene isomers. The objectives of this study were to optimize supercritical carbon dioxide (SC-CO2) extraction parameters for the isolation of the non-polar tomato by-product fraction (oleoresin) and cis-lycopene isomers by using a central composite rotatable design (CCD) model with response surface methodology (RSM). SC-CO2 using CCD and RSM was used for the first time for the isolation of cis-lycopene isomers from tomato by-products. The best results in terms of oleoresin yield were obtained at a temperature of 73.9 °C, a pressure of 53.7 MPa and a time of 155 min, whereas the optimal extraction process parameters of cis-lycopene isomers are a 52 °C temperature, a 55 MPa pressure and a 180 min extraction time. The optimized conditions of SC-CO2 allows to obtain high yields of lycopene rich extracts (oleoresins) comprising higher percentage of cis-lycopene isomers (∼62% of total lycopene).

Functional pasta with tomato by-product as a source of antioxidant compounds and dietary fibre

Tomato peels are abundant by-products of tomato processing and therefore represent a cost of disposal and an impact on the environment. For this reason, the aim of the present study was to valorise tomato peels to enrich pasta, being these ingredients still rich in antioxidants like carotenoids that are well-known to protect against degenerative diseases. To the aim of the work, in the first step, tomato peel flour was added to wholemeal flour in different amounts until the overall quality of cooked pasta reached its acceptability threshold (tomato peel flour at 15% w/w of semolina weight). Even though the pasta enriched with tomato peels showed high levels of carotenoids and dietary fibre, lower sensory scores for elasticity, odour, and firmness were recorded than in the control. Therefore, the second step was aimed to improve the sensory quality of the 15% enriched spaghetti by means of proper addition of hydrocolloids. Final results confirmed the ability of the structuring agents to enhance adhesiveness and bulkiness of pasta, without compromising other physical and chemical properties.

Biorefinery cascade processing for creating added value on tomato industrial by-products from Tunisia.

BackgroundIn today’s consumer perception of industrial processes and food production, aspects like food quality, human health, environmental safety, and energy security have become the keywords. Therefore, much effort has been extended toward adding value to biowastes of agri-food industries through biorefinery processing approaches. This study focused, for the first time, on the valorization of tomato by-products of a Tunisian industry for the recovery of value-added compounds using biorefinery cascade processing.ResultsThe process integrated supercritical CO2 extraction of carotenoids within the oil fractions from tomato seeds (TS) and tomato peels (TP), followed by a batch isolation of protein from the residues. The remaining lignocellulosic matter from both fractions was then submitted to a liquid hot water (LHW) hydrolysis. Supercritical CO2 experiments extracted 5.79% oleoresin, 410.53 mg lycopene/kg, and 31.38 mg β-carotene/kg from TP and 26.29% oil, 27.84 mg lycopene/kg, and 5.25 mg β-carotene/kg from TS, on dry weights. Protein extraction yields, nearing 30% of the initial protein contents equal to 13.28% in TP and 39.26% in TS, revealed that TP and TS are a rich source of essential amino acids. LHW treatment run at 120–200 °C, 50 bar for 30 min showed that a temperature of 160 °C was the most convenient for cellulose and hemicellulose hydrolysis from TP and TS, while keeping the degradation products low.ConclusionsResults indicated that tomato by-products are not only a green source of lycopene-rich oleoresin and tomato seed oil (TSO) and of protein with good nutritional quality but also a source of lignocellulosic matter with potential for bioethanol production. This study would provide an important reference for the concept and the feasibility of the cascade fractionation of valuable compounds from tomato industrial by-products.Graphical abstractSchema of biorefinery cascade processing of tomato industrial by-products toward isolation of valuable fractions.

Optimisation of the recovery of carotenoids from tomato processing wastes: application on textile dyeing and assessment of its antioxidant activity

The present study has been focused on the extraction of natural pigments from tomato industry waste. At first, different solvents and solvents mixture were compared to determine which one is the best for extracting carotenoids compounds from tomato by-products. A mixture of hexane and acetone gave the highest carotenoids extraction yield among the others examined. The extraction conditions were optimised using a five-level–five-factor central composite design. Under optimal conditions, solvent solid ratio 90, hexane percentage in the solvent mixture 60, extraction duration 50, number of extractions 4 and extraction temperature 35 °C, the yield of carotenoids was 80.7 μg/g. The coloured extract of tomato by-products was applied on textile fabrics to investigate the dyeing characteristics and antioxidant activities. The results indicate that extract can be applied on textile fabrics (wool, silk and polyamide) to produce coloured clothing with acceptable antioxidant properties.

Tunisian tomato by-products, as a potential source of natural bioactive compounds

Consumption of tomato and tomato products is positively related to the reduction in cardiovascular disease and several types of cancer, thanks to the presence of natural compounds, such as antioxidants. Peels and seeds fractions of tomato, collected after industrial processing in Tunisian industries, were analysed for nutritional and antioxidants composition in perspective of its utilisation. Proximate composition, fatty acids profile, carotenoids, such as lycopene and beta-carotene, polyphenols contents, demonstrated the good potential of these residual products as a source of natural compounds, useful for food and nutraceuticals applications.

Effect of Tomato Pomace Extracts on the Shelf-Life of Modified Atmosphere-Packaged Lamb Meat

Tomato production is one of the main industries in Spain and a large amount of by-products, tomato pomace (TP) is generated every year. TP is a promising source of compounds with nutritional, antioxidant and antimicrobial potential. The aim of this work was to study the in vitro antioxidant potential of extracts obtained from TP by using either ethyl acetate (EA) or ethanol (E) solvents, and to evaluate the effect of the addition of extracts by spreading on lamb longissimus thoracis surface in order to improve shelf-life. EA and E extracts showed a similar in vitro antioxidant activity which is in good relation with similar lycopene, phenol and β-carotene contents found in those extracts. Redness (a*) decrease during storage was less intense in meat longissimus thoracis with added extracts (P 0.05) in meat stored during 7 days. Microbial counts were not either affected (P > 0.05). Practical Appliactions This manuscript deals with the antioxidant and antimicrobial potential of tomato pomace by-products and specifically, their extracts. Tomato concentrate by-products are produced in a great amount, and most of them are underused as animal feed. The value of these by-products could be increased as used as potential antimicrobial and/or antioxidant agents in foods. A number of works have applied different parts of tomato by-products, such as the seed, the peel, or both, in certain food products. However, as far as we are concerned there is no scientific literature dealing with obtaining extracts from tomato pomace and adding them to meat or meat products. In this research we obtained the extracts by solvent extraction, studied their composition and in vitro potential and added them to meat in order to extend its shelf-life.

Impact of tomato lycopene on the chemical and physical properties for beef burger, which was preserved by cooling for 3 weeks.

Each of concentrated extract of tomato by-products with addition ratio 0.1, 0.2, 0.3 and 0.4%, signed as T1, T2, T3 and T4, respectively and crude tomato by-products with addition ratio 3, 4.5, 6 and 7.5%, respectively, signed as T5, T6, T7 and T8, respectively as additives in beef burger manufacture. Results of sensory evaluation of manufactured samples did detect any significantly differences between them in studies characters whereas T8 was the highest in color, treatments T1 and T8 showed its strike in flavor and the juiciness character was relevant in treatments T2 and T8. Tenderness was high for temperature T2 and T8, general acceptance in treatments T2, T7 and T8 and odor was not affected by treatments. Study of chemical and physical characters of manufacture burger through storing times which is ranged between 0-3 weeks confirmed in that samples T5-T8 maintained hydrogen number not more than 6.12 comparing samples T0 , T1, T2 , T3 and T4 which in their hydrogen numbers was increase to higher than 7.28 in the first week from storage. Water holding capacity (WHC) in samples T1, T4 and improved by 7.44% as compared with control sample (T0) which lost 12.56%. From WHC. The WHC in samples T5-T8 increased with adding percent of crude by-products and reached 7.67%. Also, the results showed that free fat acids (FFA) increased in control sample (T0) more than in other samples that increased in its peroxide value discriminately but less share; the most stable sample peroxide value was the treatment T8 that included the highest proportion of by-products 7.5%. Results of peroxide value and thiobarbituric acid value insured free fat acids tests. Whereas all samples showed stability in peroxide value and thiobarbituric acid with special superiority of samples T6, T7 and T8. For lycopene and concentration test all samples maintained saved at concentrations of lycopene and which increased with addition value. According to this, T8 had higher concentration 20.760 mg. g-1 than control sample (T0) which reached 1.285 mg. g-1 of lycopene.

Recovery and Isomerization of Carotenoids from Tomato Processing By-products

Industrial tomato processing by-products are intended mainly for animal feed or fertilizer, though they can be used for the recovery of valuable constituents. Carotenoids constitute an important component of these by-products, well credited with important health-promoting functions. This study examined the effect of several organic solvents (hexane, ethanol, acetone, ethyl acetate, ethyl lactate and their mixtures), and extraction temperature on the recovery and isomerization of carotenoids from tomato processing by-products. Another area under investigation was the stability of carotenoids, as affected by drying and storage conditions of tomato by-products. HPLC–DAD analysis was applied for the efficient separation and analysis of the carotenoids and their cis-isomers. The highest extraction yield was obtained with ethyl lactate (203.6 μg/g dry by-product) followed by hexane–ethyl acetate mixture with a considerably lower yield (36.1 μg/g dry by-product). The identified carotenoids in all solvent extracts followed the order: lycopene ≫ β-carotene > lutein, in their predominant trans-configuration. Among the identified isomers, 5-cis lycopene and 15-cis-β-carotene were the most abundant in all extracts. The increase of extraction temperature increased the total lycopene concentration in all extracts, whereas cis-isomers remained lower than 8 % in most solvents. A steadily high percentage of cis-isomer (≈30 %) was observed in ethyl lactate extracts, independent of temperature. Conversely, the increase of extraction temperature induced a reduction in total β-carotene and total lutein concentration in all solvents, while cis-isomers were not detected. Drying or even cold storage of the raw material led to decreased yields, and affected lycopene isomerization with a considerable increase of cis-isomers.

Utilization of By-product from Tomato Processing Industry for the Development of New Product

Extrusion cooking is recognized as a smart technology for food processors. It is a low cost, high temperature, short-time process. In this the starchy ingredients are input to create a puffed snack. However it contains multiple parameters that need to be rigorously controlled to develop an optimal process. Present study investigated the blends of corn flour, rice flour and tomato pomace (peel and seed), processed in a co-rotating twin-screw extruder and examined the effect of incorporation of tomato byproduct derivatives on final extruded product quality of the ready -to-eat expanded product. Furthermore, the physio-chemical properties, post cooking quality were analyzed for the extruded product. As tomato pomace, corn and rice flour are naturally gluten free, the extruded product would appeal to people who suffer from gluten intolerances, allergies and celiac disease. Dried and milled tomato peel and seed at levels of 0 - 30% and 0 - 5%, respectively were added to the formulation mix. D-optimal mixture design was chosen, which generated 17 combinations; within these combinations, the control formulation existed. The formulations were processed in a twin-screw extruder with a combination of parameters including: solid feed rate kept constant, water feed adjusted to 14%, screw speed of 300 rpm - 350 rpm and process temperatures 30°C to 140°C. It was observed that the addition of tomato pomace significantly increased the crude fiber content and level of protein content in the final product. The expansion ratio, hardness, colour, and overall acceptability varied significantly with respect to tomato pomace addition. Sensory test panel indicated that tomato pomace extrudate could be incorporated into ready-to-eat expanded products up to the level of 30% and it was acceptable. Optimization using D-optimal mixture design suggested that the best formulation extruded product with high desirability was the one consisting of 40% corn flour, 30% rice flour, 25% tomato peel and 5% tomato seed. The results suggest that tomato pomace can be extruded with corn and rice flour into an acceptable and highly nutritious fiber enriched snack food.

Olive oil enriched in lycopene from tomato by-product through a co-milling process

The aim of this investigation was to produce an olive oil (OO) naturally enriched with antioxidants, recovering carotenoids, in particular lycopene, using an industrial by-product of tomato seeds and skin. For this purpose, a technological process in a low-scale industrial plant to co-mill olives and tomato by-product in de-frosted or freeze-dried forms was applied and studied with respect to control samples. Preliminary results obtained from two different experiments were carried out by 40 kg of cultivar Correggiolo olives and 60 kg of olive blends from different cultivars. In both the experiments, the co-milling showed significant enrichment in carotenoids, especially in lycopene (mean values of 5.4 and 7.2 mg/kg oil from defrosted and freeze-dried by-products, respectively). The experimental results demonstrated the possibility to obtain a new functional food naturally enriched in antioxidant compounds, which might be marketed as “OO dressing enriched in lycopene” or “condiment produced using olives and tomato by-product”.

Mitigation strategies in the agro-food sector: The anaerobic digestion of tomato purée by-products. An Italian case study

Tomato processing involves a significant production of residues, mainly constituted by discarded tomatoes, skins, seeds and pulp. Often, these residues are not valorized and represent an added cost for manufacturing companies because of disposal processes, with environmental issues due to the difficult management. The exploitation of these residual materials results complex as their availability is mainly concentrated in few months. A possible solution is the production of biogas employed in a Combine Heat and Power engine for energy production, in line with the 2020 targets of European Union in terms of promotion of energy from renewable resources and greenhouse gas emission reduction. The tomato by-product utilization for energy production as a strategy to reduce the environmental load of tomato purée was evaluated by means of Life Cycle Assessment. Two scenarios were considered: Baseline Scenario — tomato by-products are sent back to the tomato fields as organic fertilizers; Alternative Scenario — tomato by-products are employed in a nearby biogas plant for energy production. Methane production of tomato by-products was assessed by means of specific laboratory tests. The comparison between the two scenarios highlighted reductions for all the impact categories with the Alternative Scenario. The most important reductions are related to particulate matter (−5.3%), climate change (−6.4%) and ozone depletion (−13.4%). Although small, the reduction of the environmental impact cannot be neglected; for example for climate change, the anaerobic digestion of by-products allows a saving of GHG emissions that, over the whole year, is equal to 1.567tons of CO2 eq.The results of this study could be up-scaled to the food industries with high heat demand producing considerable amounts of fermentable by-products employable as feedstock for biogas production.