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The effect of the preparation method on the physical and chemical characteristics of propolis tinctures
163-168Views:278The effect of the preparation method was examined with regards to the physical and chemical characteristics of the propolis tincture, namely the extraction time and the ethanol content of the extraction solvent to the dry matter, polyphenol, flavonoid, phosphorus, calcium and copper concentration, respectively. The dry matter, the polyphenol and the flavonoid content were the lowest in the water extract of the propolis; however, significant increase was noticed depending on the extraction time. Significantly higher concentrations were found in 50 V/V% tinctures. The highest dry matter and flavonoid contents were analysed in 100 V/V% tinctures, whereas highest polyphenol content was found in 80 V/V% tinctures. However, the differences were not significant in several cases between latter tinctures. Moreover, the increase was not determined in some cases depending on the extraction time. Phosphorus and calcium concentrations were decreased depending on the increasing ethanol content, whereas copper concentration was increased up to 80 V/V%. Higher increase was found in the case of 0 and 50 V/V% extracts than in 80 and 100 V/V% tinctures. Moreover, in latter cases, no significant differences were found on several occasions, depending on the extraction time. There was no connection between the flavonoids and the calcium as well as the phosphorus content, whereas flavonoids may be made complex with copper. However, the amount of the possible complex was negligible.
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Tendencies of various brewery operation parameters
69-74Views:188Beer is a very popular beverage which is the result of complex processes. Its quality and parameters are the outcomes of transformation of components from raw material. We tried to find out during our research how the parameters – the total polyphenol content, the colour and the total sugar content – of our self-brewed beers change during the brewing.
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Correlation between cultivation methods and quality in some vegetable species
313-317Views:150Quality parameters of 5 table root varieties were tested on 3 sowing dates with different cultivation methods: open field on 15 April and 9 July 2010 and under plastic tents on 19 August. The highest red pigment content (betanin) was measured in the varieties Akela and Mona Lisa (~ 80 mg 100 g-1) of the second (July) crop. This crop is in general use in Hungary. In comparison, in the late sown varieties (August, under plastics) a further pigment increase (10–20 mg 100 g-1) was observed in the same varieties as related to the earlier sowing dates. Yellow pigments (vulgaxanthins) showed similar trends. Roots of the late sowing date (with harvest in December) contained the highest vulgaxanthin values (103.3–124.18 mg kg-1).
Varieties reacted differently to temperature changes during the production period and thus to sugar accumulation. In the second crop (July) higher water soluble solids content was measured on the average of varieties (10.12%) in comparison to the April sowing (7.76%). Beetroots of the spring sowing are recommended for fresh market while the second (July) crop with autumn harvest can satisfy industry requirements. Late sowing under unheated plastic tents supply us with fresh beetroot in late autumn and early winter and prolong the usability of plastic tents.
Six lettuce species/subspecies were tested in the open field and under plastic tents in 3 repetitions for nitrate nitrogen, vitamin-C, polyphenol (gallus acid equivalent – mg GAE 100 g-1) and mineral element (Ca, K, Mg, Na) contents. Our measurements showed lower nitrate nitrogen values under plastic than in the open field (89.10± 8.13 and 127.06±14.29 mg kg-1) on the average of genotypes. Lettuce grown in the field had higher vitamin-C content (1.4 mg%) which is nearly 50% more than in plants under plastic. The highest polyphenol content was found in samples from the field with a conspicuous value of 804.17±56.47 mg GAE 100 g-1 in Piros cikória. Samples grown under plastic were richer in mineral elements (Ca, K, Mg, Na) which can be explained by the higher nutrient content of the soil. In this environment superior Mg content was observed in Edivia (4616.33±
311.21 mg kg-1).Besides the well- known headed lettuce, Piros cikória (Red chicory),the red leaved Lollo Rossa and Tölgylevel (Oak leaf lettuce) should be
mentioned which well deserve further testing in order to supply us with nourishing, healthy food. -
Leaf and root evaluation of bioactive compounds of different beetroot varieties
135-139Views:220The importance of beetroot lies in the numerous health benefits, attributed to its wide-ranging array of minerals, vitamins and bioactive compounds which play a key role in the human diet. Generally, beetroot is consumed for its root, however, its leaves also contain a good amount of bioactive compounds. The experiment was carried out with four beetroot varieties in order to compare the amount of bioactive compounds in the root and the leaf. The analyzed data were total dry matter content, total polyphenol, flavonoid and vitamin C.Results have shown that roots contain the highest amount of bioactive compounds. Nevertheless, leaves can be also considered a significant source. Therefore, consumption of the young leaves is highly recommended due to their availability after thinning or at maturity stage (60 days after the germination). Of the examined varieties, ‘Libero’ demonstrated the highest total polyphenol, flavonoid and vitamin C values, although it was found to be statistically insignificant. -
Changing of antioxidant and sugar contents of self brewed beers during the brewing steps
161-166Views:221Beer is a valuable beverage, its composition is influenced by raw materials and technology. We tried to determine how the technological steps influence the antioxidant content, the colur value, and the carbohydrate content, and how fruit syrups influence the antioxidant content and the colour value.
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Differences in content of beet root and beet root juice, and it’s suitable to develop functional foods from animal sources
53-57Views:352In Western medicine is beginning to increasingly focus on the key role of healthy nutrition and lifestyle in preventing certain diseases. Therefore, it is important to emphasize the importance of primary prevention in our country, and to promote it; not only the health care team work, but broaden the recommended foods, which have benefit for human health as well.
Polyphenols are antioxidants, which are easily consumable with diet, however, food processing can influence the level of them.
In our study, nutritional assessment was made of raw beet root and a juice, made from this beet root. We investigated in which special diet referenced to eat this foods and whether this is suitable to develop functional foods from animal sources as a row material.
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The effect of sous-vide cooking on the antioxidant properties of oyster mushroom (Pleurotus ostreatus L.)
177-184Views:165Oyster mushrooms (Pleurotus ostreatus L.) are renowned for their antioxidant, antimicrobial, and prebiotic properties. This study explores the antioxidant characteristics, activity, and β-glucan content in freeze-dried mushroom samples, investigating the influence of sous-vide cooking. Uncooked freeze-dried P. ostreatus and three pre-cooked freeze-dried samples (70, 80, 90 °C through 4 hours) were analysed for Total Polyphenol Content (TPC), Total Flavonoid Content (TFC), Radical Scavenging (DPPH), Ferric Reducing Antioxidant Power (FRAP), and β-glucans content via HPLC and Total Dietary Fiber (TDF) via enzymatic gravimetric method. Results indicate that uncooked mushroom powder exhibited superior antioxidant capabilities compared to cooked samples. The sous-vide cooked (80 °C) mushrooms displayed the highest total phenolic and flavonoid content. Moreover, pre-cooked (70 °C) mushroom powder demonstrated the highest β-glucan content, significantly surpassing the uncooked control sample. Notably, pre-cooked groups (80, 90 °C) demonstrated significantly higher TDF levels compared to uncooked sample. This research offers valuable insights into the potential use of mushrooms as high-antioxidant, antimicrobial, and prebiotic food or feed supplements, with broad implications across various fields.
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Development of the antioxidant indexes (FRAP, TFC, TPC) of scabbing resistant apple varieties in storage
89-94Views:155One of the most important groups of bioactive substances in apples are antioxidants, which have a health-preserving effect. The amount of these compounds varies not only during the ripening of the apple fruit, but also continuously during post-harvest storage. A growing group of health-conscious consumers are looking for apple varieties with a nutritional value that satisfies their needs.
In the scope of our research, we examined 5 apple varieties originating from the Derecske horticultural site of KITE cPlc. in 2016. The plantation was planted to be suitable for intensive apple production. Samples were collected at the time of maturity (August-October) of the given variety. The 5 examined apple varieties (Gaia, Isaaq, Modí, Smeralda and Fujion) are all resistant to apple scab (fungal disease caused by Venturia inaequalis). The 2-month storage experiment was conducted at 16–17 °C, which had an aggressive effect on our stored apples. Total polyphenol (TPC) and flavonoid (TFC) content as well as FRAP values of the apples were measured. Measurements were taken immediately after harvest and after 1 and 2 months of storage. Our results were evaluated by using the IBM SPSS Statistics 20 software. Our aim was to compare the antioxidant results of 5 scab-resistant apple varieties, which change continuously during storage.
The antioxidant content of our apple varieties increased during 2 months storage. The best result was achieved by the Modí apple variety (FRAP: 467.32 mg/100g; TFC: 317.76 mg/100g; TPC: 1771.97 mg/100g). Consumers may want to consume apples stored for a longer period of time if they are to absorb large amounts of antioxidants.