## 2 Materials and Methods
### Methods  
Samples preparation for analytical and microbiological tests: sprout samples were weighed (20.0 \(\pm\) 0.01 g) into sterile plastic containers with a screw cap, then treated with solutions (10.0 \(\pm\) 0.01 mL) of individual organic acids by spraying them, and then the excess fluids were drained. The samples were stored in containers in a sterile cooler (temperature 4 \({}^{\circ}\)C, relative humidity 85%). After the end of the storage period, analytical and microbiological tests were performed. Microbiological analysis: The microbiological analysis of sprouts was carried out in accordance with the PN-EN ISO 4833-1:2013-12 standard [42], which was used to determine the total number of microbial colonies at 30 \({}^{\circ}\)C, time of analysis: 3 days. The number of yeasts and molds was determined in accordance with the PN-ISO 21527-2: 2009 standard [43] at 25 \({}^{\circ}\)C, time of analysis: 5 days. Extraction of bioactive ingredients: 5.0 g of fresh red cabbage sprouts were scaled (with 0.001g accuracy) (AS 220/X, Radway, Radom, Poland) into a plastic, falcone tubes with a screw top (50.0 mL capacity) and 30.0 mL of the water-methanol mixture in the volume of 30:70 was added. It was shaken in a vortex shaker (Wizard Advanced IR Vortex Mixer, VELP Scientific Srl, Usmate, Italy) for 60 s. After that, the samples were incubated in a shaking incubator in 60 \({}^{\circ}\)C (IKA KS 4000i Control, IKA Ltd., Warsaw, Poland) for 2 h. Then the samples were shaken anew in a vortex for 60 s to receive a thorough mixture, centrifuged in a refrigerated centrifuge (MPW-380 R, MPW Med. Instruments, Warsaw, Poland) for 15 min (4 \({}^{\circ}\)C, 10.000 rpm) and finally the obtained supernatant was collected and used for the determination of the antioxidant capacity and the total content of polyphenols. The same procedure was used to obtain extracts in red cabbage. Determination of antioxidant properties: Antioxidant activity of red cabbage sprouts extracts were determined by using ABTS** (2,2'-azino-bis (3-ethylbenzothazoline-6-sulphonic) acid) (Sigma-Aldrich, Poznar, Poland) radical cation assay according to modified [PERSON] et al. (1999) method [44]. The principle of the method is based on the measurement of the ability to deactivate synthetic ABTS** cation species by antioxidant compounds contained in the tested material. A certain quantity of the tested extracts' solution (determined by a designated dilution scheme) was drawn into 10 mL glass test tubes. After that, 3.0 mL of radical cations ABTS** in PBS (Phosphate Buffer Solution, Sigma-Aldrich, Poznar, Poland) solution were added. The absorbance measurements were made after exactly 6 min of incubation the samples in about 20 \({}^{\circ}\)C. The absorbance were measured at the wave length of \(\lambda\) = 734 nm, with the use of spectrophotometer (UV/Vis UV-6100A, Metash Instruments Co., Ltd., Shanghai, China). The results were calculated based on the calibration curve (y = \(-\)5.6017x + 0.7134, R\({}^{2}\) = 0.9998) for Trolox (Sigma-Aldrich, Poznar, Poland) and represented as uM TEAC (Trolox Equivalent Antioxidant Capacity) per 1g of fresh weight (f. w.) red cabbage sprouts. The same procedure was used to determine the antioxidant properties in red cabbage. Determination of the content of polyphenic compounds: Total polyphenols content in red cabbage sprouts were measured by the reaction between polyphenol compounds with Folin-Ciocalteu and sodium carbonate (Sigma-Aldrich, Poznar, Poland) reagents using a modified method of [PERSON] (1965) [45]. The method is based on the reduction of molybdenum (VI) to molybdenum (V) contained in the Foli-Ciocalteu reagent by polyphenol-like compounds present in the tested samples in an alkaline environment of sodium carbonate. A defined amount of red cabbage sprouts extracts, based on the dilution scheme, were collected into 50 mL graduated flasks, then 2.5 mL of Folin-Ciocalteu reagent and 5.0 mL of 20% sodium carbonate solution were added and made up to the mark with distilled water.