Tsvetko Prokopov

Prof. Tsvetko Prokopov

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 September 2019 in Molecules
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VPVenelina Popova
Venelina Popova
TITanya Ivanova
Tanya Ivanova
TPTsvetko Prokopov
Tsvetko Prokopov
MNMilena Nikolova
Milena Nikolova
ASAlbena Stoyanova
Albena Stoyanova
Valtcho ZheljazkovValtcho Zheljazkov
Valtcho Zheljazkov
Tobacco (Nicotiana tabacum L.) aroma is an important attribute of tobacco quality and is influenced by a variety of minor chemical components, including carotenoid degradation products. The objectives of this work were to determine the content of the most important fragrance-shaping carotenoid degradation products in the essential oils (EOs) of the three types of Bulgarian tobacco—Oriental (OR), flue-cured Virginia (FCV), and Burley (BU)—and to compare them with other aromatic products from tobacco. The content of total carotenoids and β-carotene was highest in BU tobacco (22.23 and 20.34 mg/100 g DW, respectively), followed by OR (13.60 and 12.09 mg/100 g DW in variety “Plovdiv 7” (Pd7); 6.27 and 5.45 mg/100 g DW in “Krumovgrad” (Kr), and FCV (5.93 and 3.73 mg/100 g DW). EOs were obtained by hydrodistillation in an acidified medium, and the main aroma-impact compounds from carotenoid degradation (identified by GC-MS) were as follows: FCV-α-ionone (0.61 mg/100 g DW), dihydro-β-ionone (0.96 mg/100 g DW), β-damascenone (1.26 mg/100 g DW); BU-α-ionone (0.73 mg/100 g DW), dihydro-β-ionone (1.19 mg/100 g DW), β-damascenone (1.35 mg/100 g DW); OR(Kr)-α-ionone (0.20 mg/100 g DW), β-ionone (1.08 mg/100 g DW), dihydro-β-ionone (1.34 mg/100 g DW), β-damascenone (0.36 mg/100 g DW); OR(Pd7)-α-ionone (1.43 mg/100 g DW), dihydro-β-ionone (1.73 mg/100 g DW), β-damascenone (1.23 mg/100 g DW). Ionone and its derivatives were not identified in the aroma extraction products concrete, resinoid, or absolute. The results suggest that temperature, pH of the medium, process duration, and possibly other unknown factors affect carotenoid transformation. The study provides insight into the composition of tobacco EOs and may be of interest to the fragrance industry.

7 January 2020 in British Food Journal
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Journal Article
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STSilviya Atanasova Topleva
Silviya Atanasova Topleva
TPTsvetko Prokopov
Tsvetko Prokopov
Purpose: The ecological footprint of the food industry and the requirements of the bio-based economy result in the need for deepening the concept of corporate sustainability. CSR provokes the implementation of eco-innovation with high value added. A main source of value added and sustainability is the integrated implementation of ecodesign practices . The purpose of this paper is to systemize an integrated model for the product ecodesign implementation, which combines not only the industrial and process ecodesign but also the overall organizational and socio-economic context of SMEs in food industry, reflected in CSR and value added for stakeholders.Design/methodology/approach: The methodology for implementation of business model for sustainability of the SMEs in the food industry through ecodesign is based on vertical and horizontal integration of well-known self-relevant environmental, social and economic tools such as corporate social responsibility, life-cycle assessment, MET matrix, ecolabelling and stakeholder approach for production and marketing of high-value-added eco-products.Findings: This study proposes an algorithm for implementation of an integrated business model for SMEs sustainability in the food industry, focusing on high-value-added delivery for stakeholders, based on corporate social responsibility, functional innovation and eco-efficiency. The ecodesign based on CSR business practice in food industry allows simultaneous optimization of environmental aspects and cost structure of products in conditions of improved quality and functionality. Thus, ecodesign contributes to the diversification not only of the company’s product portfolio, but also to opening of new marketplaces and the implementation of new market strategies by increasing the value added.Practical implications: The research identifies actions, which SMEs in food industry can follow to achieve ecological redesign of their business and production processes that simultaneously enhance product functionality and resource efficiency.Originality/value: The academic and the social value of the research is the focus on ecodesign and its implementation in SMEs in the food industry as a tool for creation of multidimensional high value added for stakeholders in bio-based economy.

1 October 2015 in International Agrophysics
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TPTsvetko Prokopov
Tsvetko Prokopov
Zhivka GoranovaZhivka Goranova
Zhivka Goranova
MBMarianna Baeva
Marianna Baeva
ASAnton Slavov
Anton Slavov
CGCharis M. Galanakis
Charis M. Galanakis
The main objective of this study was to develop high fibre cakes utilizing and valorising cabbage by-products - cabbage outer leaves. Cabbage outer leaves were dried and milled in order to produce cabbage leaf powder. The cabbage leaf powder was added at 0, 10, 20% into sponge cake. All of the samples were subjected to physicochemical analysis and sensory evaluation. Methods of descriptive sensory analysis were used for a comparative analysis of the sponge cakes with cabbage leaf powder and the cake without cabbage leaf powder. Addition of cabbage leaf powder in sponge cakes significantly affected the cake volume and textural properties. Springiness of cakes with cabbage leaf powder and crumb tenderness were lower, while the structure was stable at high loads, as expressed by lower shrinkage in comparison with the control cake. The nutritional value of the sponge cakes with cabbage leaf powder was lower than the control cake. The cells cakes modified by cabbage leaf powder were smaller and almost equal, uniformly distributed in the crumb, and at the same time had thicker walls. The cakes with addition of cabbage leaf powder showed the springiness and their crumb tenderness were lower, while their structure was stable at high loads. Control cake showed higher water-absorbing capacity compared to the cakes with 10 and 20% cabbage leaf powder.

20 October 2018 in Journal of Food Science and Technology
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TPTsvetko Prokopov
Tsvetko Prokopov
VCValentina Chonova
Valentina Chonova
ASAnton Slavov
Anton Slavov
TDTzvetelin Dessev
Tzvetelin Dessev
NDNikolay Dimitrov
Nikolay Dimitrov
Nadezhda PetkovaNadezhda Petkova
Nadezhda Petkova

1 March 2017 in Acta Alimentaria
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Journal Article
Closed access
TPTsvetko Prokopov
Tsvetko Prokopov
MNM. Nikolova
M. Nikolova
GDG. Dobrev
G. Dobrev
DTD. Taneva
D. Taneva
Enzyme-assisted extraction of carotenoids from tomato peels of the Bulgarian cultivar “Stela”, one of the most widely used cultivars by the canning industry, was examined in this study. The carotenoid content in raw tomato peels was established by HPLC analysis. A two-step protocol was followed: the tomato peels were first treated with enzymes and then extracted by the use of acetone as a solvent for 30 min at 20±1 °C and solid/liquid ratio of 1:30. The total carotenoid, lycopene, and β-carotene extraction yields were increased by the use of pectinase, cellulase, endo-xylanase, and proteinase enzymes in comparison with the non-enzyme-treated samples. The increase in the extraction yield was affected by the enzymes used, the enzyme concentration, the pretreatment time and temperature. Maximum total carotenoid (55.15 mg/100 g d.w.), β-carotene (35.85 mg/100 g d.w.), and lycopene (15.44 mg/100 g d.w.) extraction yields were obtained in peels pretreated with mixed cellulase (100 U g−1) and endo-xylanase (400 U g−1) for 4 h at 50 °C. Carotenoid recovery by mixed cellulolytic and hemi-cellulolytic enzyme pretreatment of tomato peels is a good approach, which can be used for waste utilization.

1 June 2018 in Acta Alimentaria
Verified
Journal Article
Open access
TPTsvetko Prokopov
Tsvetko Prokopov
ASAnton Slavov
Anton Slavov
Nadezhda PetkovaNadezhda Petkova
Nadezhda Petkova
VYV. Yanakieva
V. Yanakieva
BBB. Bozadzhiev
B. Bozadzhiev
DTD. Taneva
D. Taneva
The development of food products that contain value-added dietary fibre beside different classes of phytochemicals is of great interest nowadays. The present research aimed to evaluate the powder obtained from onion processing waste (OPW) for its potential use as a value-added by-product in food sector. Data on chemical and microbiological characterization of onion processing waste powder (OPWP) were obtained. The dietary fibre content and antioxidant activity were also determined. The results showed that the OPWP was a low-calorie natural source of insoluble fibres (60.52±0.13 g/100 g dw), total phenols (41.04±1.22 mg GAE/g dw), and total flavonoids (20.44±1.22 mg QE/g dw). Moreover, the OPWP could be considered as an important source of total fructans (9.04±0.28 g/100 g dw), fructooligosaccharides (2.76 g/100 g dw), and inulin (2.41±0.18 g/100 g dw). In conclusion, this OPWP could be used as a value-added and healthy food ingredient.