Tomato Processing Industry Research Articles

Recent advances in the utilization of industrial byproducts and wastes generated at different stages of tomato processing: Status report

There has been an increasing focus on addressing the generation of byproducts and waste from food industries, intending to reduce carbon footprint, and improve the circular economy. Post-harvest processing of tomatoes generates byproducts and waste at various stages of industrial processing. Pomace (seed, peel, and pomace liquid) of processed tomato which constitutes valuable compounds for various commercial purposes. Generated waste from tomato processing is used for extraction of the carotenoids, preparation of the adsorption material and also as animal feed. The generated byproduct/waste has the scope to be utilized for different food (such as seed oil, lycopene as a natural colorant and as a good antioxidant compound for food product development and its stability) and non-food purposes such as dried byproduct/waste as adsorption material for removal of synthetic dyes and heavy metals from the aqueous waste, etc. This review aims to address the byproducts generated at different stages of unit operation during the processing of tomato since these byproducts have different matrix compositions at various stages of processing, and also summarizes the recent advancement in their utilization. Novelty impact statement This review provides the insight on byproducts generated in tomato processing industry at different stages and their use for food and non-food purposes. For the first time pomace liquid produced in tomato industrial processing has been discussed for its possible application.

Tomato skin drying

The aim of this work was to study the convective drying of tomato skin as by-product of tomato processing industry and the influence of this operation on the lycopene content extracted with Moringa oleifera oil. The effect of combining of air temperatures (40, 55 and 70 °C) and air velocities (1, 2 and 3 m/s) on the drying kinetics of tomato skin were studied. Diffusional and empirical models were fitted to the experimental data. The effect of the drying conditions on the lycopene content was determined from its extraction in moringa oil. Temperature and air velocity combination had a significantly (p > 0.05) influence on the drying kinetic. This combination can promote a reduction on the lycopene content. Drying process was satisfactory described by diffusional and empirical models and their coefficients were reported for the material investigated. A threshold range of air velocity with influence on the external resistance to the moisture transfer was detected.

Prediction of Soluble Solids and Lycopene Content of Processing Tomato Cultivars by Vis-NIR Spectroscopy.

Tomato-based products are significant components of vegetable consumption. The processing tomato industry is unquestionably in need of a rapid definition method for measuring soluble solids content (SSC) and lycopene content. The objective was to find the best chemometric method for the estimation of SSC and lycopene content from visible and near-infrared (Vis-NIR) absorbance and reflectance data so that they could be determined without the use of chemicals in the process. A total of 326 Vis-NIR absorbance and reflectance spectra and reference measurements were available to calibrate and validate prediction models. The obtained spectra can be manipulated using different preprocessing methods and multivariate data analysis techniques to develop prediction models for these two main quality attributes of tomato fruits. Eight different method combinations were compared in homogenized and intact fruit samples. For SSC prediction, the results showed that the best root mean squared error of cross-validation (RMSECV) originated from raw absorbance (0.58) data and with multiplicative scatter correction (MSC) (0.59) of intact fruit in Vis-NIR, and first derivatives of reflectance (R2 = 0.41) for homogenate in the short-wave infrared (SWIR) region. The best predictive ability for lycopene content of homogenate in the SWIR range (R2 = 0.47; RMSECV = 17.95 mg kg–1) was slightly lower than that of Vis-NIR (R2 = 0.68; 15.07 mg kg–1). This study reports the suitability of two Vis-NIR spectrometers, absorbance/reflectance spectra, preprocessing methods, and partial least square (PLS) regression to predict SSC and lycopene content of intact tomato fruit and its homogenate.

Enhancing the bioaccessibility of lycopene from tomato processing byproducts via supercritical carbon dioxide extraction

Tomato peel and seed from tomato processing industry are treated as waste; however, they contain lycopene, a high-value bioactive compound. In this study, lycopene was extracted from tomato peel and seed using supercritical carbon dioxide (SC–CO2) and hexane, and the bioaccessibilities of lycopene in the SC-CO2- and hexane-extracted oleoresins were investigated for the first time. The (Z)-lycopene content of the SC-CO2-extracted oleoresin (69%) was higher than that of hexane-extracted oleoresin (45%). Separation of the insoluble fraction from the oleoresins increased the (Z)-lycopene contents of the SC-CO2- and hexane-extracted oil fractions to 80% and 49%, respectively. The bioaccessibility of total-lycopene in the oleoresins was increased by 3.3-fold via SC-CO2 extraction, which was attributed to higher (Z)-lycopene content, and small-sized uniform distribution of lycopene in the oleoresin. SC-CO2 extraction is not only a green method for extraction of bioactive compounds, but also has the potential to improve health benefits of bioactive compounds.

Up-cycling tomato pomace by thermochemical liquefaction – A response surface methodology assessment

Tomato pomace is a waste from the tomato processing industry, for which there are few solutions to upcycle it. The tomato pomace thermochemical liquefaction was modelated using response surface methodology, combined with central composite face-centred (CCF), obtaining a model with a high adjusted R-squared (0.97) and a very good p-value (less than 0.001). The liquefaction process was conducted for 1–5 h at temperatures ranging from 100 to 160 °C. The process was supported by an acid catalyst, p-toluene sulfonic acid, with concentrations from 0.5 to 3% w/w. The model suggested that the highest conversions are reached at 160 °C, for a catalyst concentration from 2.5% to 3%, and for processes lasting more than 3 h. The bio-oil obtained was characterized by FTIR-ATR, elemental analysis, thermogravimetric analysis, and the higher heating value was computed. The bio-oil’ HHV was estimated at 32.32 MJ/kg, 1.42 times higher than that of tomato pomace. The study indicates that thermochemical liquefaction can be a process to value the tomato pomace, turning it into bio-fuel or value-added chemicals.

Improving nutritional quality of unripe tomato through fermentation by a consortium of yeast and lactic acid bacteria.

Portugal is one of the main producers of industrial tomato and tomato paste, an important intermediate ingredient used in many added-value foods. The tomato processing industry rigorously selects the fruits by colour during mechanical harvest, picking only completely ripe fruits to produce high quality tomato paste. The latest available data shows that about 1.12 × 108 kg yr-1 of non-red/not-ripe tomatoes are left in the field, representing a major side product/field residue with great impact on the environment and for tomato producers. The aim of the work was to use fermentation by a consortium of yeast and lactic acid bacteria to improve the nutritional quality of unripe tomato paste. A consortium of Lactobacillus plantarum, Leuconostoc mesenteroides and Kluyveromyces marxianus was selected, producing an acidic paste with olive-like flavours after 4 days of fermentation. Nutritional characterization revealed a significant improvement (P< 0.05) in the content of ascorbic acid and antioxidant potential. In addition, ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) analysis showed that the fermented green tomato paste content in glycoalkaloid α-tomatine represents no hazard to the consumer. Therefore, the obtained fermented green tomato paste can be further used to produce new food products, such as salad dressings and sauces. © 2021 Society of Chemical Industry.

Recent Advances in Recovery of Lycopene from Tomato Waste: A Potent Antioxidant with Endless Benefits.

Growing attention to environmental protection leads food industries to adopt a model of “circular economy” applying safe and sustainable technologies to recover, recycle and valorize by-products. Therefore, by-products become raw material for other industries. Tomato processing industry produces significant amounts of by-products, consisting of skins and seeds. Tomato skin is very rich in lycopene, and from its seeds, high nutritional oil can be extracted. Alternative use of the two fractions not only could cut disposal costs but also allow one to extract bioactive compounds and an oil with a high nutritional value. This review focused on the recent advance in extraction of lycopene, whose beneficial effects on health are widely recognized.

Drying of tomatoes and tomato processing waste: a critical review of the quality aspects

Tomatoes are a valuable highly perishable agricultural product that are dried on a large scale for extending shelf life. The drying of both tomatoes and tomato processing waste can yield valuable products. The dried forms serve as raw material for different commercial products, as an ingredient for functional foods. It is also used all over the world for direct consumption. However, the production of dried forms with quality attributes equivalent to those of fresh tomatoes such as the nutrient content, appearance, flavor, texture, reconstitution properties etc. are major challenges. This paper provides an overview of the diverse drying techniques employed along with the effects of pretreatment to produce dried tomatoes, powders, and various by-products of tomato processing industries. A comparison is provided with regard to the quality of dried tomato products obtained by different drying techniques for lycopene content, ascorbic acid, β-carotene, total phenolic content, flavonoids, antioxidant activity, rehydration ratio, color change, texture, and flavor.

Supply Chain Analysis of Raw and Value-added Products of Tomatoes in Telangana

Tomato (Solanum lycopersicum L.) is one of the most widely consumed vegetable crops and the second-largest cultivated vegetable crop in the world after potato. Tomato is one of the most important protective foods because of its special nutritive value. Tomatoes grown in the country are consumed fresh in raw or cooked form or processed into tomato paste, juice, sauce, ketchup, soup and, pickles. Less than one percent of India’s tomato production is processed. On the other hand, the demand in India for processed tomato products has been growing at an annual rate of about 30 per cent over the last few years. India is the World's largest producer of many fruits and vegetables but there still exists a huge gap between per capita demand and supply due to enormous wastage during post-harvest storage, handling, and the absence of an optimum supply chain. The price fluctuations in tomatoes are very high and often farmers are forced to sell at prices that will not cover even the labor cost of picking the tomatoes. A well-developed tomato processing industry will reduce wastages as well as secure better prices for tomatoes. The present study entitled “Supply chain analysis of raw and value-added products of tomatoes in Telangana” was intended to assess supply chain analysis for raw and processed tomato products along with the constraints faced by each stake holder in the supply chain. Vikarabad district was purposively selected for the study, two mandals four villages each were selected from each village, data was collected from 10 farmers. Hence the total data was collected from 80 farmers. The data was also collected from commission agents, wholesalers/ traders, and retailers. From the tomato processing firms operating in around Hyderabad, three firms were selected to collect data regarding their products and marketing supply chain. The collected data was analyzed.&#x0D; The results of the study identified three channels of raw tomato marketing, namely: channel-I Farmer- Commission Agent-Trader-Retailer-consumer, Channel-II Famer – Commission agent - Retailer-consumer and Channel-III Farmer- Retailer-consumer. Two channels of processed tomato products were identified, namely: Channel-I, Manufacturing unit- wholesalers-consumers and Channel-II, Manufacturing unit- consumers.&#x0D; The producer share in the consumer rupee was highest in the Channel -III because of lesser number intermediaries. The marketing efficiency is highest for the channel – III fallowed by channel – II and channel -I. In case of processed industries are mostly preferring channel -II. The major constraints to the farmers identified were high price fluctuations, high cost of fertilizers and pesticides. The major constraints to the intermediaries identified were high price fluctuations and transportation costs and problems. The major problems identified were lack of quality raw materials suitable for processing, and price fluctuations of raw materials for the processing units, while the major problems faced by wholesalers identified were timely availability and quality related issues.

Identification of tomatoes with early decay using visible and near infrared hyperspectral imaging and image‐spectrum merging technique

AbstractEffective detection of tomatoes with early decay still remains one of the major problems in the post‐harvest processing. The feasibility of using visible and near infrared (Vis–NIR) hyperspectral reflectance imaging coupled with image‐spectrum merging processing and analysis technology to detect early decay on tomatoes was observed. Mean normalization method was used to correct the uneven illumination caused by the large curvature change and the reflective characteristics of tomato surface. Principal component (PC) clustering analysis of spectra was used to find the optimal PC that was then used to distinguish sound and decayed tissues of tomatoes. Based on the selected PC, three characteristic wavelengths images at 596, 666, and 858 nm were obtained and the new combination image was calculated. The pseudo‐color image processing and RGB (red, green, and blue) transformation were applied to enhance the contrast between decayed and sound regions on the combined image. G component of RGB image and the corrected single‐wavelength image at 666 nm were used for segmentation of the decayed region and stem‐end on tomatoes, respectively. All samples including 120 decayed and 120 sound tomatoes were used to assess performance of the proposed algorithm. The classification results indicated that 100% of the decayed fruit and 97.5% of sound fruit were accurately identified by proposed algorithm. This study demonstrated that Vis–NIR hyperspectral imaging coupled with image‐spectrum merging processing technology could be a potential approach for detection of tomatoes with early decay.Practical applicationsDecay will not only affect the quality of tomato products, but also cause serious food safety problems. Detection of decayed tomatoes has become an universal attentive and urgent solving question for tomato processing industry. Currently, there was no effective and rapid technology to classify between decayed and sound tomatoes. In this study, a novel method was developed and the decayed tomatoes were successful identified using only three characteristic wavelengths images. This study can provide a useful reference for development of fast multispectral imaging system for decayed tomato detection in practical on‐line grading applications.

Selection of industrial tomatoes using TD-NMR data and computational classification methods

Tomato processing chain has a world economic relevance for the food industry and the agribusiness, providing ready-to-eat products and raw material for other production chains. The product quality is depending on control of some fruit attributes, such as color, soluble solids content (SSC), and defects. The aim of this study was to develop accurate and nondestructive classification models according to the tomato maturation stage, SSC, and presence of defects using Time-Domain Nuclear Magnetic Resonance (TD-NMR) associated with computational classification methods. Each class showed different decay times. Green tomatoes showed a shorter decay signal than red tomatoes, mainly due to the relaxation signal being related to the water mobility in different vegetable tissue compartments. Classification models resulted in great accuracy performances, the best accuracy for each classification were: maturity index: 97% (SVM); SSC: 100% (SVM and kNN); presence of defects: 90% (PLS-DA). These results show that CPMG decays associated with computational methods can be used in the tomato processing industry to classify tomato samples. These classification models showed the potential of TD-NMR technique in a high-throughput screening application before the processing.

Evaluation of the Bioactive Compounds Found in Tomato Seed Oil and Tomato Peels Influenced by Industrial Heat Treatments.

The circular economy action plan involves principles related to food waste reduction and integration of recovered nutrients to the market. In this context, the present study aims to highlight the valuable bioactive components found in tomato processing by-products (carotenoids, phenolic compounds and fatty acids) influenced by industrial pre-treatments, particularly cold break (CB) process at 65–75 °C and hot break (HB) process at 85–95 °C. The fatty acid profile of the tomato seed oil was examined by gas chromatography coupled to mass spectrometry (GC-MS), individual carotenoid and phenolic compositions were determined by high performance liquid chromatography (HPLC) and the viscoelastic properties were evaluated by rheological measurements. The physicochemical properties revealed appropriate characteristics of the tomato seed oil to fit the standards of generally accepted edible oils, for both CB and HB derived samples, however, significant qualitative and quantitative differences were detected in their phenolic composition and carotenoids content. Lycopene (37.43 ± 1.01 mg/100 mL) was a major carotenoid in the examined samples, linoleic acid was the main fatty acid (61.73%) detected in the tomato seed oil and syringic acid appeared to be one of two major phenolic acids detected in the samples of CB process. Our findings extend the boundaries of tomato processing industry by validating that tomato seed oil is a bioactive rich edible oil with additional health benefits, which can be integrated in functional food products.

Extraction, Purification and Characterization of Lycopene from Tomato (Cv Vijeta) Processing Industry Waste

Aim: The present study focused on extraction of lycopene from tomato processing industry waste, its purification and characterization by different methods. Lycopene is major carotenoid found in tomato.&#x0D; Methodology: Different tomato parts like whole tomato, tomato peel and waste generated druing processing were also screened for lycopene content. The extracted lycopene was purified by crystallization method. The purified lycopene was characterized by the different methods live UV- spectroscopy, HPLC, FT-IR and NMR.&#x0D; Results: Among the different parts of tomato the peel (377.19±1.13 µg/g) contain highest amount of lycopene than industrial waste (175.15±1.09 µg/g) and whole tomato (82.82±0.79). The crystallization method significantly purify the lycopene content which was clearly resulted in UV-spectroscopy, HPLC, FT-IR and NMR results.&#x0D; Conclusion: This will be beneficial to the industry for purification and characterization of lycopene from tomato processing industry waste.

Optimization of pretreatment and enzymatic hydrolysis conditions of tomato pomace for production of alcohols and esters by Kluyveromyces marxianus

Tomato pomace (TP) is generated as a natural by product in a significant amount in the tomato processing industry, and it is a good source of lignocelluloses to produce some high-value products from fermentable sugars (FS). The present study was performed to produce FS by using either ultrasound-assisted dilute acid (UADA) or heat-treated dilute acid (HTDA) pretreatments of TP followed by enzymatic hydrolysis (EH). When HTDA and UADA were compared in terms of FS (g/L) concentration, HTDA pretreatment generally produced more FS content than UADA. The optimum conditions for HTDA pretreatment were the application of 2.5% H2SO4, 10% (w/v) solution of TP, and heating at 121 °C for 6 min, which yielded 31 g/L FS concentration. Beside the optimized conditions for EH of HTDA, pretreated TP required 1.5% of enzyme concentration and 6 h of hydrolysis time. In conclusion, the most abundant volatile organic compounds (VOCs) produced by K. marxianus in final tomato pomace hydrolysate (TPH) were isoamyl alcohol, phenyl ethyl alcohol, ethyl acetate and phenyl ethyl acetate in a 5-L bioreactor. Nine descriptive sensory terms were developed to characterize fermented TPH. The rose and sweet floral aromas were defined as aroma characteristics for TPH fermented by K. marxianus.

Effect of different tomato pomace compost as organic fertilizer in sweet maize crop

ABSTRACT Pomace from tomato paste is produced in great amounts after tomato processing industries in Greece. The aim of this study is to evaluate tomato pomace as fertilizer in sweet maize cultivation. Two-year experiments were set up in West Greece under organic cultivations. The experiments followed a randomized complete block design, with four treatments, with which were different fertilizer applications (control, Tomato pomace, Tomato pomace & inorganic fertilizer (NPK), Tomato pomace & manure) in three replications. The root density, root surface, and symbiotic of arbuscular mycorrhizal fungi (AMF) were statistically affected by fertilization for both years, and the combination of Tomato pomace (Tp) and manure gave the highest values. Organic carbon (C) was significantly affected by year and fertilization, as well as the total nitrogen (N) was significantly affected by fertilization. Soil porosity under tomato pomace and mix of tomato pomace and inorganic fertilizer do not show statistically significant differences. The highest values for plant growth and leaf area index were under the combination of tomato pomace and manure. The yield was statistically affected by fertilization and year. Therefore, tomato mixtures with manure as well as compost had the most positive results in almost all parameters of the studies.

Application of an innovative water-assisted ultraviolet C light technology for the inactivation of microorganisms in tomato processing industries

We aimed to study the efficacy of a water-assisted UVC light device (WUVC) as an innovative clean technology for the disinfection of fresh sound tomatoes and processing wash water and water turbidity was evaluated as a critical parameter. First, wash waters with different turbidities (from 0.4 to 828 NTU) were inoculated with Listeria innocua and treated in the WUVC device at different dosages. Secondly, fresh tomatoes, inoculated with L. innocua and non-inoculated ones, were treated using the WUVC device containing wash water of different turbidities for different times. The reduction of L. innocua populations on wash water and on the surface of tomato was influenced by turbidity; lower reduction values were observed at higher turbidities. Washing tomatoes with tap water with UVC lamps off (control treatment, TW) decreased L. innocua population on the surface of tomatoes but did not eliminate those bacteria that went into the water. Contrarily, when UVC lights were on, L. innocua population in wash water after treatment significantly decreased, those in clean water being the lowest populations. Reductions of native microbiota on the clean water treated with the highest UV-C radiation dose were lower than those obtained when tomatoes were artificially inoculated. We demonstrated that high reductions of L. innocua population on fresh tomatoes could be achieved using the WUVC system but some drawbacks related to the increase of turbidity should be solved for its implementation in real conditions.

PROCESS INTENSIFICATION OF TOMATO RESIDUES DRYING BY MICROWAVE HEATING: EXPERIMENTS AND SIMULATION

Drying of wet wastes from tomato processing industry was investigated as a critical step prior to their valorization to energy and/or to value-added chemicals. Microwave drying (MWD) was considered because of its advantages over conventional drying. A lab-scale MW oven equipped with automatic temperature control allowed operating at “constant temperature” rather than at “constant magnetron power”, as occurred in past research. MWD tests were performed in batch mode at three temperatures (50, 60 and 70 °C) and the results were compared with those from hot air drying (HAD) experiments. Based on experimental data, an empirical kinetic equation was developed for the microwave drying of tomato wastes as a function of moisture content and temperature. The rate equation was incorporated into a lumped-parameter mathematical model for a steady-state MWD process, which in turn was embedded in an Aspen PlusTM flowsheet used for the gross sizing of a continuous microwave belt dryer.Compared with HAD, MWD allows reducing the drying time up to one order of magnitude (i.e., from 320 to 100 min at 50 °C and from 190 to 60 min at 70 °C), but implies an investment cost one order of magnitude larger (i.e., from about 0.2 to 0.9 M€).

Tomato waste extract (Lycopersicon esculentum) as a natural antioxidant in soybean oil under heating

The tomato processing industry generates a large amount of waste, usually composed of peels and seeds. It is known that the tomato is rich in bioactive compounds, mainly carotenoids (lycopene and ?-carotene), however, studies on the functionality of its residues are scarce. Thus, these residues are discarded without the knowledge of possible antioxidant potential. The objective of this work was to determine the stability of bioactive in soybean oil added to the extract of agroindustrial tomato waste under heating. The extract obtained with ethyl alcohol at the ratio of 1: 5 (w/v) was initially analyzed for total phenolic compounds, lycopene, ?-carotene, and antioxidant activity using the DPPH and ?- carotene / linoleic acid. Subsequently, the extract and the synthetic antioxidants, butylhydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ) were applied in soybean oil, and the treatments subjected to heating in Rancimat (180oC/5 h). The thermoxidated samples were analyzed for the composition of tocopherols by high-performance liquid chromatography (HPLC), phytosterols, and fatty acid profile by gas chromatography (GC). The extract of agro-industrial tomato residues showed moderate results concerning its antioxidant activity, 68% by the DPPH method, and 26.2% of auto-oxidation of the ?-carotene / linoleic acid system. The synthetic antioxidant TBHQ had a greater protective effect on soybean oil when compared to the control, providing greater retention of phytosterols (85%) and tocopherols (93%). Tomato extract can be used as a natural antioxidant in industrialized oils, but with less effectiveness than the antioxidant TBHQ.

Variation in secondary metabolites in a unique set of tomato accessions collected in Turkey

In this study, 50 tomato landraces grown in Turkey were investigated in terms of their secondary metabolite profiles. Each accession was planted in 2016 and 2017 in 3 replicates in an open field. In this study, color, pH and brix of the fruit samples were measured and an unbiased LCMS-based metabolomics approach was applied. Based on Principal Components Analysis (PCA) and Hierarchical Cluster Analysis (HCA) of the relative abundance levels of >250 metabolites, it could be concluded that fruit size was the most influential to the biochemical composition, rather than the geographical origin of accessions. Results indicated substantial biodiversity in various metabolites generally regarded as key to fruit quality aspects, including sugars; phenolic compounds like phenylpropanoids and flavonoids; alkaloids and glycosides of flavour-related volatile compounds. The phytochemical data provides insight into which Turkish accessions might be most promising as starting materials for the tomato processing and breeding industries.

Effects of Tomato Pomace Composts on Yield and Quality of Processing Tomato (Lycopersicon esculentum Mill.)

Organic farming encourages the use of organic waste materials as substitutes for chemical fertilizers. Tomato pomace presents an alternative to inorganic fertilizer. A field experiment was carried out to evaluate the influence of tomato pomace composts and nitrogen fertilization on agronomic and quality parameters of the processing tomato. The experiment was laid out in a randomized complete block design with three replications and five fertilization treatments (untreated, nitrogen fertilizer, tomato pomace with biocyclic humus soil, tomato pomace with manure and tomato pomace with plant residues). The results showed that the highest average fruit weight and fruit yield (163.4 t/ha) were found in plots subjected to nitrogen fertilization, while the highest total soluble solids content (4.29 °Brix), and L* and a* colour parameters, important quality parameters to processing tomato industry, were obtained through the application of tomato pomace mixed with biocyclic humus soil making organic tomatoes suitable for processing tomato industry.