Changes of vitamin C content in celery and parsley herb after processing

Humans and other primates have lost the ability to synthesize vitamin C and therefore the only source is diet. Vitamin C or ascorbic acid has labile nature, it is removed or destroyed in specific degree immediately after harvest, but storage and post - harvest processing also contribute to its degradation. The aim of work was to determine the vitamin C content in the herb of selected celery and parsley varieties in dependence on chosen postharvest processing and to compare it with fresh herb. There were chosen five bulb forms varieties of celery (Apium graveolens) - Makara, Ilonaa, Hegy Köi, Talar and Diamant. In case of parsley (Petroselinum crispum) there were evaluated one variety of curly parsley, one variety of herb parsley - Petra, and five varieties of root parsley - Lenka, Eagle, Ginate D´Italia, Titana and Arat. Every variety was harvested in three terms, followed by vitamin C content estimation in fresh herb, after drying and after freezing. The content of vitamin C was estimated by HPLC method by the help of liquid chromatograph with UV detector. There was found the significant difference in content of vitamin C in parsley as well as in celery when comparing the fresh herb with herbs after post - harvest processes - drying (by air circulation in laboratory hall) and freezing. After processing of herbs in both observed species the vitamin C content decreased, in case of freezing it was about 65% (celery) and 61% (parsley), after drying about 86% (celery) and 82% (parsley) in comparison with fresh herb. The effect of processing played more important role in influencing of vitamin C content than variety in case of both selected species. For using of celery and parsley not only as culinary herb, but as a notable source of ascorbic acid it is the most important fresh herb intake

Impact of nutrition on the quality and quantity of cauliflower florets

Cauliflower (Brassica oleracea var botrytis) as a member of the family Brassicaceae belongs to worldwide popular vegetable with using in all kinds of cuisine. The aim of the work was to find out the effects of nutrition and fertilization (in dependence on the amount of nitrogen) on the yield of florets as well as on selected qualitative characteristics - vitamin C, nitrate and sulforaphane content. Analyses were done by the help of liquid chromatograph (HPLC) with UV detector for separation. The trial was led in Nitra, Slovakia, in 2014 - 2015. Cauliflower variety CHARLOT F1 was selected for testing. Four variants have been examined in the trial: control (without application of fertilizers), N150S80 (application of nitrogen and sulphur at the supply level N: S = 150:80 kg.ha-1), N200S80 and N250S80. Application of nitrogen led to significant increasing of the yields of primary cauliflower florets in case of the dose 200 and 250 kg N.ha-1 (increasing about 87% and 134% compared to control). Applied nitrogen nutrition caused significant nitrates increasing in monitored cauliflower florets in order of the variants: 1 (control) <2 (N = 150 kg.ha-1) <3 (N = 200 kg.ha-1) <4 (N = 250 kg.ha-1), but the highest dosage of nitrates is still under the permissible standard according to Food codex of Slovak republic (700 mg.kg-1 of FM). The influence of differentiated nutrition on sulforaphane content was statistically confirmed in case of the 4th variant in comparison to control, where the decrease about 40% was noticed. Influence of nitrogen fertilizing according to used methodology on vitamin C (AA) content was not statistically confirmed. The nutrient concentration in the curds and stalks of cauliflower varied insignificantly with levels of nitrogen applied

Quantitative and qualitative parameters in Acorn squash cultivar in the conditions of the Slovak Republic

The species Cucurbita pepo includes several types of squashes; in Slovak Republic, well-known and oftenly grown squash types are patisson, zucchini, spaghetti squash, oil pumpkin etc. Several interesting squash types of Cucurbita pepo are grown abroad, including Acorn squash which is well-known mainly in USA. The aim of this study was to evaluate the important quantitative (yield per hectare, average fruit weight) and qualitative (total carotenoids, ascorbic acid, antioxidant activity, total soluble solids) yield parameters of Acorn squash fruits in comparison with patisson which is typical squash type of Cucurbita pepo in Slovak Republic. The field trial was realised in Košice-Šaca in 2016. Within experiment, four cultivars of Acorn type pumpkin were tested (Thelma Sanders; Jet Set; Table Gold; Cream of The Crop). The patisson 'Orfeus' was used as a comparative cultivar for evaluation of individual parameters of Acorn type pumpkin cultivars. Matured pumpkin fruits were harvested on the 7th September 2016. From aspect of yield quantity, Acorn cultivars are appeared as very interesting squash type with good yield potential for growing. The highest yield of squash fruits was found in the cultivar 'Cream of The Crop' (17.8 t.ha-1). In mentioned Acorn cultivar, the yield was higher about 87.4% compared to the tested patisson cultivar 'Orfeus' (9.5 t.ha-1). On the contrary, the average weight of squash fruits was reached in patisson cultivar 'Orfeus' (780.7 g). The qualitative parameters of fruits were expressively influenced by squash cultivar. The content of total carotenoids, ascorbic acid and total soluble solids was markedly higher in all Acorn cultivars, compared to the patisson cultivar 'Orfeus'. The highest content of total carotenoids (26.74 mg.kg-1 fresh weight) and ascorbic acid (238.79 mg.kg-1 f. w.) was found in the squash cultivar 'Table Gold'. The highest content of total soluble solids was determined in the cultivar 'Jet Set' (3.8 °Brix). On the contrary, the highest antioxidant activity (DPPH) was found in the patisson cultivar 'Orfeus' (10.80 %). On the basis of obtained results, it is possible to state that Acorn cultivars are very interesting squash type with promising yield potential for possible growing in conditions of Slovak Republic. In addition, Acorn squashes were expressed by higher content of several nutritional parameters compared to the typical squash type - patisson. Thus, these squashes could be an interesting vegetable for human nutrition

Evaluation of quantitative and qualitative characteristics of selected celery (Apium graveolens var. Dulce) varieties in the context of juices production

Celery, Apium graveolens var. Dulce (Mill.) is a biennial plant, lesser used in Slovakia in comparison with celeriac, but with increasing popularity because of its very health beneficial properties. The aim of the study was to evaluate quantitative (yields) and qualitative (chlorophyll a and b, soluble solids) parameters in selected patioles of celery in the context of raw juice production in a small-plot field experiment. Six varieties of celery (var. Dulce) were planted - ´Helios´, ´Red Soup´, ´Malachit´, ´Verde Pascal´, ´Golden Self- Blanching´ and ´Celebrity´. The harvest was carried out twice a season in terms of August and September. The chlorophyll a and chlorophyll b were determined spectrophotometrically, Total soluble solids were estimated by the help of refractometer. The lowest values in yields reached ´Malachit´variety, the highest ´Red Soup´ variety. In the evaluation of both harvests the ´Celebrity´ and ´Golden S.´ varieties showed the lowest chlorophyll content. The total soluble solid content reached values ranging from 5.00 to 8.77 °BRIX, in the following order: ´Celebrity´ <´Helios´ <´Golden S.´ < ´Red Soup´ <´Verde Pascal´. The term of harvest had significant influence on chlorophyll a and b. The effect wasn´t confirmed on yields and soluble solids according to used statistical analyse. There were mainly other kind of characteristics followed in previous scientific studies about celery (var. Dulce), such a flavonoids, vitamins, minerals, fibre,  the essential oils and phenolic acids, etc. Processing to juices or smoothies allow consuming of other antioxidant - chlorophyll

Vplyv odrody na vybrané kvantitatívne a kvalitatívne parameter batátov (Ipomoea batatas L.) pestovaných v Slovenskej republike

The sweet potato (Ipomoea batatas L.) is less-known vegetable species in Slovak Republic. It is known for sweet taste and various possibilities of use in gastronomy. In this study, the effect of cultivar on the important quantitative (yield of marketable tubers per plant, average weight of marketable tubers, yield of marketable tubers per hectare, share of marketable tubers) and qualitative (antioxidant activity, polyphenol content) parameters of sweet potatoes grown in Slovak Republic was tested. The highest yield (1964.16 g/plant; 54.56 t/ha) and average weight (446.18 g) of marketable tubers (> 150 g) were found in white sweet potato cultivar \u27Višnjica white\u27. The highest ratio of marketable tubers was found in orange cultivar \u27Beauregard\u27 (87.17%). The purple cultivar \u27Višnjica purple\u27 was characterized by significantly lower values of all quantitative parameters of sweet potatoes. On the contrary, the highest antioxidant activity (61.07% DPPH; DPPH: 2,2-Diphenyl-1-picrylhydrazyl) and polyphenol content (4506.90 mg/kg dry weight) were found just in purple cultivar \u27Višnjica purple\u27. The significantly higher values of both parameters, compared to other cultivars, are caused by abundance of anthocyanins. Results of this study revealed that sweet potato is expressed by good yield potential, together with its quality, in conditions of Slovak republic, or Middle Europe in generally.Povojník batátový (Ipomoea batatas L.) je menej známym druhom zeleniny v Slovenskej republike. Batáty sa vyznačujú sladkou chuťou a ich využitie v gastronómii je rôzne. V rámci štúdie bol sledovaný vplyv odrody na významné kvantitatívne (úroda predajných hľúz z rastliny, priemerná hmotnosť predajných hľúz, úroda predajných hľúz hektára, podiel predajných hľúz) a kvalitatívne (antioxidačná aktivita, celkový obsah polyfenolov) parametre batátov pestovaných v Slovenskej republike. Najvyššia úroda (1964,16 g/rastlina; 54,56 t/ha) a priemerná hmotnosť (446,18 g) predajných hľúz (> 150 g) boli zistené u bielej odrody batátov \u27Višnjica biela\u27. Najvyšší podiel predajných hľúz bol dosiahnutý u oranžovej odrody \u27Beauregard\u27 (87,17%). Fialová odroda \u27Višnjica fialová\u27 bola sa vyznačovala výrazne nižšími hodnotami u všetkých sledovaných parametrov. Na druhej strane, najvyššia hodnota antioxidačnej aktivity (61,07% DPPH; DPPH: 2,2-Diphenyl-1 picrylhydrazyl) a obsah polyfenolov (4506,90 mg/kg suchej hmoty) boli zistené práve u uvedenej fialovej odrody \u27Višnjica fialová\u27. Výrazne vyššie hodnoty oboch parametrov, v porovnaní s ostatnými odrodami, sú zapríčinené prítomnosťou antokyanínov v hľuzách batátov. Výsledky štúdie odhalili, že batáty sa v podmienkach Slovenskej republiky, resp. strednej Európy, vyznačujú dobrým úrodovým potenciálom a kvalitou dopestovaných hľúz

Total polyphenol content and antioxidant capacity changes in dependence on chosen garden pea varieties

The green pea is ranged between the crops with high antioxidant potential. This potential is connected with phytochemical components mainly with polyphenols. All these bioactive chemicals have disease - fighting properties. In real human diet there is no usually possibility of fresh garden pea consumption during the whole year. The total polyphenol content is significantly changed among other things by processing methods. Focus on variety, bio-fortification and other specific agricultural inputs, could be the right method of total polyphenol contents and total antioxidant capacity increasing. The main objective of the present work was to consider the changes of total polyphenols content in dependence on variety and to evaluate an antioxidant potential six garden pea varieties arranged by the ripening point of view. Variety “Exzeleus” belongs to very early type, ́Premium ́ is early maturing,”Flavora” is middle ripening variety and the last three varieties “Utrio”, “Jumbo” and “Ambassador” are middle late types of varieties. Every variety was grown in four replications, i.e. on 24 m2 total plot in Botanical garden of Slovak University of Agriculture in Nitra during 2013. Total polyphenols were determined by the Lachmans method and expressed as mg of gallic acid equivalent per kg fresh mater. Total antioxidant capacity was measured by the Brand - Williams method using a compound DPPH (2.2-diphenyl-1-pikrylhydrazyl)). The highest value was reached in case of variety “Jumbo” 1179.995±28.081 mg/kg, the lowest value in case of “Premium” 674.505 ±26.541 mg/kg. When evaluating an antioxidant capacity in chosen varieties of garden pea, the interval estimated by our trail ranged from 0.523 ±0.206% (“Exzeleus”) to 6.844 ±0.591% (“Flavora”) Following the both observed parameters, TPC and TAC, variety “Flavora” (as a member of middle ripening varieties) seems to be the most optimal from the human nutrition point of view. The various varieties had significant influence on TPC and TAC according to used statistical analyzes. Within the all observed varieties, when they were arranged by ripening, there was estimated significant difference only in case of garden pea varieties early – middle late. Other couples didn’t show any statistical important differences in total polyphenol content

The influence of selenium on selected heavy metals cumulation in Oyster mushroom fruiting bodies

Food safety is a very frequent topic. The article deals with the problems of fortification of the most grown mushroom in Slovakia, and the 3rd most grown mushroom in the world, Pleurotus ostreatus. Due to the high environmental pollution of soils and air, there is a risk of the production of dangerous fruiting bodies with high heavy metals content. It is known that these substances can promote serious health effects on human body, such as bone weakness or kidney damages (cadmium) and negative process of cognitive developing (lead). The experiment was focused on biofortification with selenium to reduce the accumulation of selected heavy metals (lead, cadmium) in oyster mushroom, grown with intensive cultivation under artificial conditions. This work confirms that the application of sodium selenate to the growing substrate with straw as the main component can reduce the accumulation of cadmium (by 22.45%) and lead (by 64.81%). Research by various authors reported the ability of the oyster mushroom to embed selenium from the substrate into the fruiting bodies. Based on the results of the experiments, we propose to fortify the growing substrate for the production of oyster mushroom by selenium. This way we produce a food with a high antioxidant potential

The evaluation of selected qualitative parameters of sweet potato (Ipomoea batatas L.) in dependence on its cultivar

The sweet potato (Ipomoea batatas L.) is relatively known vegetable species, but it is grown only on small area in the Middle European region. Its cultivars are characterized by different colour of tuber flesh which can be white, beige, yellow, orange and purple. The aim of this study was to determine and compare selected qualitative parameters of tubers (total carotenoids, vitamin C and total soluble solids) among orange, white and purple sweet potato cultivars. The field experiments were established at Slovak University of Agriculture in Nitra in 2016 and 2017. Sweet potatoes were grown by hillock system with using of black non-woven textile for soil mulching. The tuber harvest was realised on the 6th October 2016 and 13rd September 2017. The highest content of total carotenoids was found in orange sweet potato cultivars (78.47 - 122.89 mg.kg-1 fresh weight) and its values were multiple-fold higher in comparison with purple (4.22 mg.kg-1 f. w.) and white (10.71 mg.kg-1 f. w.) cultivars. Orange cultivars were also richer source of vitamin C (246.31 - 325.99 mg.kg-1 f. w.) compared to white (179.66 mg.kg-1 f. w.) and purple (187.75 mg.kg-1 f. w.) cultivars of sweet potatoes. The total soluble solids, expressing mainly sugar content, was higher in purple (10.13 °BRIX) cultivar of sweet potatoes, followed by cultivars with orange (8.52 - 9.72 °BRIX) and white (5.57 °BRIX) tuber flesh. Obtained results showed the significant effect of cultivar, characterized by different tuber flesh colour, on the composition and contribution of sweet potatoes for human health.

Less-known Leaf Vegetables Grown in Slovak Republic Conditions: New Sources of Antioxidants

The goal of this study was to determine the content of bioactive substances (chlorophyll, carotenoids, vitamin C) in less-known leafy vegetable species, such as Chinese mustard (Brassica juncea (L.) Czern. Et Coss.), mibuna (Brassica rapa ssp. japonica Makino) and mizuna (Brassica rapa ssp. nipposinica (Bailey) Hanelt). Within study, two cultivars of Chinese mustard were tested, concretely cv. Ruby Streaks (purple leaves) and cv. Spicy Green (green leaves). The field experiment was realised on the land of Slovak University of Agriculture in Nitra in 2014 and 2015. The highest content of chlorophyll a and chlorophyll b, as the biologically most active chlorophyll types, was found in mibuna leaves. The Chinese mustard cv. Ruby Streaks was shown as the richest source of total carotenoids. The highest vitamin C content was found in leaves of Chinese mustard cv. Spicy Green. Compared to the typical leafy species like spinach, all tested less-known vegetable species were indicated as the comparable sources of chlorophyll. The content of other tested substances, such as carotenoids and vitamin C, was even higher than results presented in studies of several authors with spinach

Qualitative and quantitative characteristics of Serbian tomato varieties grown in conditions of Slovak republic

The aim of submitted article was to estimate qualitative and quantitative characteristic of Serbian tomato varieties grown in conditions of Slovak republic and to compare the results with control tomato variety and evaluate their potential for the Slovak market. There were included 6 Serbian tomato varieties: &acute;Fantom VFCTm F1&acute;, &acute;Marathon ASVF F1&acute;, &acute;Honey Heart VF F1&acute;, &acute;Uragan SVF F1&acute;, &acute;Kazanova F1 VF&acute;, &acute;Dinka F1&acute; and &acute;Tornado F1&acute; in control variant, which is wide spread in Slovak tomato production. As qualitative characteristic for every variety total yields (in kg) per every plant, total number of harvested fruits (in pieces for each plant) and average weight of one fruit in kg were evaluated. In Department of vegetable growing laboratory qualitative characteristics in case of all chosen tomato varieties were estimated (included firmness of fruits, total carotenoids estimation, ascorbic acid estimation). Serbian varieties reached lower total yields per plant. From the &acute;fruit weight&acute; point of view they created more or less homogenous group of bigger and heavier fruits in comparison with &acute;Tornado F1&acute; and statistically significant homogenous group when focusing on total number of fruits per plant in comparison with &acute;Tornado F1&acute; variety. Differences between control variant and chosen Serbian varieties were even more considerable in case of qualitative characteristics, where &acute;Tornado F1&acute; reached the lowest values in case of all observed characteristics - firmness of fruits, total carotenoids and ascorbic acid content. According to increasing importance of antioxidants in human diet, all tested Serbian varieties appeared to be very interesting for Slovak consumers from following both qualitative and quantitative characteristics.<!--[endif] --