Potravinarstvo Slovak Journal of Food Sciences

https://potravinarstvo.com/journal1/index.php/potravinarstvo/issue/feed Potravinarstvo Slovak Journal of Food Sciences 2022-01-04T12:55:59+00:00 doc. Ing. Peter Zajác, PhD. editor@potravinarstvo.com Open Journal Systems Welcome to administration panel https://potravinarstvo.com/journal1/index.php/potravinarstvo/article/view/1715 Polyphenol components and antioxidant activity of Thymus spp. 2022-01-04T12:55:59+00:00 Olena Vergun olenavergun8003@gmail.com Liudmyla Svidenko svid65@ukr.net Olga Grygorieva olgrygorieva@gmail.com Vladimíra Horčinová Sedláčková vladimira.sedlackova@uniag.sk Katarína Fatrcová Šramková katarina.sramkova@gmail.com Eva Ivanišová eva.ivanisova@uniag.sk Ján Brindza Jan.Brindza@uniag.sk

This scientific work was aimed to evaluate the antioxidant potential of aromatic plants of Thymus spp. in the East of Ukraine. These plants are known as medicinal and food around the world. All antioxidant parameters were investigated spectrophotometrically: total content of polyphenols (TPC), the total content of phenolic acids (TPAC), the total content of flavonoids (TFC), molybdenum reducing power of extracts (MRP), and antioxidant activity by DPPH method (DPPH). Investigation of ethanolic extracts demonstrated that TPC varied from 57.89 to 123.67 mg/g gallic acid equivalent (GAE) DW for Th. pulegioides, from 61.43 to 168.18 mg GAE/g for Th. serpyllum, and from 47.36 to 115.67 mg GAE/g for Th. vulgaris. TPAC ranged from 27.36 to 50.22 mg/g caffeic acid equivalent (CAE) DW for Th. pulegioides, from 28.58 to 59.62 mg CAE/g for Th. serpyllum, and from 22.95 to 53.82 mg CAE/g for Th. vulgaris. TFC was determined in a range from 29.88 to 61.23 mg/g quercetin equivalent (QE) DW for Th. pulegioides, from 36.0 to 82.43 mg QE/g for Th. serpyllum, and from 24.59 to 55.41 mg QE/g for Th. vulgaris. MRP was detected in the range of 94.65 – 204.76 mg/g Trolox equivalent (TE) DW for Th. pulegioides, 96.06 – 219.0 mg TE/g for Th. serpyllum, and 87.56 – 215.43 mg TE/g for Th. vulgaris. The antioxidant activity of extracts by the DPPH method was 6.34 – 9.23 mg TE/g for Th. pulegioides, 8.11 – 9.21 mg TE/g for Th. serpyllum, and 4.97 – 9.53 mg TE/g for Th. vulgaris. It was established that polyphenol accumulation depended on the growth stage and species. For all species was found a strong correlation between TPC and TFC (r = 0.938, 0.908, and 0.854). Investigated Thymus spp. are a valuable source of antioxidants that can be used in pharmacological studies and the food industry.

2022-01-01T00:00:00+00:00 Copyright (c) 2021 Potravinarstvo Slovak Journal of Food Sciences https://potravinarstvo.com/journal1/index.php/potravinarstvo/article/view/1711 The intensification of dehydration process of pectin-containing raw materials 2022-01-04T12:55:56+00:00 Igor Palamarchuk vibroprocessing@gmail.com Oksana Zozulyak ksuxazoz1980@gmail.com Mikhailo Mushtruk mixej.1984@ukr.net Ievgenii Petrychenko 22102210g@ukr.net Nataliia Slobodyanyuk slob2210@ukr.net Оlexander Domin domin31@gmail.com Sergiy Udodov kiypivo@gmail.com Olena Semenova tata_t@2008ukr.net Inna Karpovych inkarp@ukr.net Roksolana Blishch roksolanaalex1976@gmail.com

The process of intensifying dehydration of pectin-containing raw materials by using centrifugation with simultaneous application of low-frequency oscillations to the working container creates an electroosmotic effect in unilateral diffusion to improve the filtration process. It is established that to reduce the technological resistance in the presented methods; it is necessary to create a fluidized bed of products due to the oscillating motion of the working capacity. An experimental vibration unit has been developed to determine the rational parameters of the vibrocentric moisture removal process using the electroosmotic effect. It is proved that the complex of the designed equipment provides consecutive carrying out of three-stage vibration filtration-convective drying of high-moisture production by an alternation of action of a stream of the heat carrier, an electromagnetic field, low-frequency fluctuations. According to the research results, the dependences of the kinetics of the moisture diffusion process on the electric field strength are obtained; frequency of electric current and duty cycle of pulses, which allowed to optimize the process parameters according to the criteria of minimizing energy consumption. It was found that the processing time to achieve the desired humidity with the application of vibration, filtration, and electroosmotic effect was twice less than for filtration drying in a fixed bed. In combination with the noted physical and mechanical factors, the proposed technology improves the technical and economic parameters of the studied process.