scholarly journals Physico-Chemical Indices, Iso-alpha-Acid, Phenolic Contents and Antioxidant Activity of Commercial Beers

2013 ◽  
Vol 2 (4) ◽  
pp. 107 ◽  
Author(s):  
Antonietta Baiano ◽  
Carmela Terracone

<p>The effects of brewing style on physicochemical indices, iso-a-acids and antioxidant contents of commercial beers were investigated. A great variability was highlighted for all the considered parameters (sugar and alcohol contents, density, pH, titratable acidity, iso-a-acids, phenolic content, antioxidant activity). The beers having the highest iso-a-acids contents were Guinness Special Export Stout (which also showed the highest phenolic content), Chimay Pères Trappistes Triple, and Greene King IPA whereas the lowest values were detected in Cuveè De Ranke, Heineken Premium Quality Lager, and Riedenburger Brauhaus gluten free. The latter also had the lowest phenolic concentration. The antioxidant activity values strictly correlated with the total phenolic content but not with the iso-?-acid amount. The Principal Component Analysis failed in distinguishing beers based on their declared type/styles. This was a predictable result since the beer styles don’t represent a compositional classification but they are rather used to indicate commercial types.</p>

2020 ◽  
Vol 70 (12) ◽  
pp. 4187-4192

Physico-chemical parameters of Romanian sea buckthorn fresh or dried berries, including titratable acidity (2.28±0.06 g malic acid/100 g FM), pH (2.60±0.08), contents of moisture (75.94±2.14 g/100 g FM), ash (2.83±0.11 g/100 g DM), ascorbic acid (1337.6±37.2 mg/100 g FM), oil (3.82±0.16 g/100 g FM), and macro elements, mainly K (11654 mg/kg DM), Mg (668 mg/kg DM), Ca (645 mg/kg DM), Na (401 mg/kg DM), and P (271 mg/kg DM), were evaluated in this paper. The most abundant volatile compounds found in the volatile fraction of berries were isopentyl isovalerate (30.8%), heptanal (11.7%), ethyl hexanoate (10.5%), ethyl isovalerate (8.1%), hexanal (7.5%), and ethyl 2-methylbutyrate (6.3%). Total phenolic content, total flavonoids content, and antioxidant activity (expressed as DPPH free radical scavenging activity by inhibition of DPPH) of extract solutions obtained from dried berries by MAE using ethanol/water mixture as a solvent were estimated at different ratios of solvent volume/vegetal material mass (15-30 mL/g) and ethanol/water (50/50, 60/40, 70/30, and 80/20 v/v). Inhibition of DPPH (22.61-48.60%) was well correlated with total phenolic content (4.42-10.04 mg caffeic acid equivalents/g DM) and total flavonoids content (5.37-11.14 mg quercetin equivalents/g DM). Keywords: Sea buckthorn, ascorbic acid, titratable acidity, oil, volatiles, minerals, total phenols, total flavonoids, antioxidant activity


2008 ◽  
Vol 7 (1) ◽  
Author(s):  
Bimo Budi Santoso

<strong><em>Flavanoid, steroid, and terpenoid contents of 20 Manokwari medicinal plants were analyzed.  The antioxidant activity, total phenolic contents and antitumor activity of 20 Manokwari medicinal plants were also evaluated. The result shows that 83% positif to flavanoid test, 59% positif to terpenoid test and only 25% positif steroid. Antioxidant activity and total phenolic contents evaluated using Ferric Thiocianate (FTC) and Folin-Ciocalteu methods respectively. Antioxidant activity and total phenolic contents of medicinal plants were extracted by the traditional method, boiling in water and also in 80% methanol. Twenty plants evaluated in both exstracts have significantly varies of antioxidant activities and phenolic contents,  A significant and linier correlation coefficient between the antioxidant activity and the total phenolic content was found in both aqueous (R<sup>2</sup>= 0,77) and methanol (R<sup>2</sup> = 0,85). Antitumor activity was tested using cell maurine P-388 and only 2 of medicinal plants are active to inhibit cell maurine P-388. Comparing extraction efficiency of the two methods, the methanol extracted phenolic compounds more efficiently, and antioxidant activity of the extract was higher.</em></strong>


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1579
Author(s):  
Mariam Sardiñas-Valdés ◽  
Hugo Sergio García-Galindo ◽  
Alfonso Juventino Chay-Canul ◽  
José Rodolfo Velázquez-Martínez ◽  
Josafat Alberto Hernández-Becerra ◽  
...  

The influence of nano-emulsified curcumin (NEC) added to the hair sheep milk, prior to cheese-making, on the chemical composition, lipolysis, and proteolysis of manchego-style cheeses were evaluated throughout 80 days of ripening. The addition of NEC to the milk resulted in cheeses with the same moisture content (42.23%), total protein (23.16%), and water activity (0.969) (p > 0.05). However, it increased the fat and ash levels from 26.82% and 3.64% in B 10 ppm to 30.08% and 3.85% in C 10 ppm, respectively, at the end of the ripening (p < 0.05). The total phenolic content and antioxidant activity of experimental cheeses increased during ripening, and the fatty acid groups showed significant changes occurred to a greater extent in the first days of ripening (p < 0.05). The lipolysis increased consistently in all cheeses until day 40 of ripening, to decrease at the end, while proteolysis increased during all ripening time in all samples (p < 0.05); the addition of NEC did not alter the primary proteolysis of manchego-style cheeses, but it modified secondary proteolysis and lipolysis (p < 0.05). Principal component analysis was useful for discriminating cheeses according to their chemical composition and classified into four groups according to their ripening time. This research highlights the potential of CNE to fortify dairy foods to enhance their functionality.


2017 ◽  
Vol 37 (1) ◽  
pp. 7 ◽  
Author(s):  
Aisyah Tri Septiana ◽  
Mohammad Samsi ◽  
Mustaufik Mustaufik

Indonesia traditional beverages such as minuman jahe, kunyit asam, beras kencur, and minuman temulawak are usually made with the addition of spices. They can be served in the form of  liquid or powder. This research was aimed to study the effect of  the beverage type, addition of spices, and the form of product on their antioxidant activity. The type of sugar used in this study was palm sugar juice. Total phenolic contents were measured to  indicate the level of antioxidants. Measurement of antioxidant  activity was conducted by analyzing malonaldehyde from linoleic  acid and capturing capacity of DPPH radical. The results showed  that Indonesian traditional beverage could inhibit the oxidation of linoleic acid and capture free radicals. Free radical capturing  capacity of curcuma beverage greater than other beverages, but  the malonaldehyde (MDA) inhibitor effect was not different. Total phenolic content of curcuma tended to be higher than the other traditional beverages. The addition of spices could raise the level  of total phenolic content in beverages and increase free radical  trapping capacity. Drying the beverages into powder could reduce the levels of total phenolic content and but did not reduce the  antioxidant activity. ABSTRAKMinuman tradisional Indonesia seperti minuman jahe, kunyit  asam, beras kencur, dan minuman temulawak biasanya dibuat  dengan tambahan berbagai rempah. Minuman tersebut dapat  disajikan dalam bentuk cair maupun serbuk. Penelitian ini  bertujuan untuk mengetahui pengaruh jenis minuman,  penambahan rempah tambahan, dan bentuk minuman terhadap aktivitas antioksidan minuman. Jenis gula yang ditambahkan  adalah gula nira. Jenis antioksidan yang diuji adalah total fenolik. Pengukuran aktivitas antioksidan dilakukan dengan uji  penghambatan malonaldehid dan kapasitas penangkapan radikal  DPPH. Hasil penelitian menunjukkan bahwa minuman  tradisional Indonesia dapat menghambat oksidasi asam linoleat dan menangkap radikal bebas. Kapasitas penangkapan radikal  bebas oleh minuman temulawak lebih besar dibandingkan  minuman yang lain tetapi kemampuan penghambatan  malonaldehid (MDA) oleh minumaan tradisional tidak berbeda.  Total fenolik minuman temulawak cenderung lebih besar  dibandingkan minuman tradisional yang lain. Penambahan  rempah-rempah dapat meningkatkan kadar total fenolik  minuman dan meningkatkan kapasitas penangkapan radikal  bebas. Pembuatan minuman serbuk pada penelitian ini dapat  menurunkan kadar total fenolik tetapi tidak menurunkan aktivitas antioksidan.


Author(s):  
Bui Thanh Tung ◽  
Dang Kim Thu ◽  
Nguyen Thi Kim Thu ◽  
Nguyen Thanh Hai

AbstractBackgroundRoscoe has been used in traditional medicine for the treatment of neurological disorder. This study aimed to investigate the phenolic contents, antioxidant, acetylcholinesterase enzyme (AChE) inhibitory activities of different fraction ofMethodsThe roots ofResultsOur data showed that the total phenolic content of EtOAc fraction was highest equivalents to 35.2±1.4 mg quercetin/g of fraction. Our data also demonstrated that EtOAc fraction had the strongest antioxidant activity with ICConclusionsOur results suggest that the EtOAc fraction of


2012 ◽  
Vol 66 (5) ◽  
pp. 723-726 ◽  
Author(s):  
Boris Pejin ◽  
Jelena Bogdanovic-Pristov

A limited number of mosses have ever been studied in regard to antioxidant activity; with only few belonging to the European species. As part of our on-going screening of bryophytes as natural antioxidant resources, a relevant biological activity investigation was conducted on the three moss species, namely Brachythecium rutabulum (Hedw.) Schimp. (Brachytheciaceae), Calliergonella cuspidata (Hedw.) Loeske (Hypnaceae) and Hypnum mammillatum (Brid.) Loeske (Hypnaceae), collected in Germany. The antioxidant activity of corresponding lyophilised aqueous extracts (teas) was evaluated on the basis of their ABTS [2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] cation scavenging activities. The total phenolic contents were determined as well. This study led to the detection of a moderate total phenolic content of the moss B. rutabulum, indicating for the first time its potential in searching for novel antioxidant agents.


Author(s):  
Tuğba Kök Taş ◽  
Erkut İlay ◽  
Ayla Öker

The aim of this study is to determine the quality characteristics of kefir by developing different flavours in order to increase its consumption. Plum (10%) and molasses (7.5%) which are rich in phenolic contents are used to produce kefir in different flavours. Chemical analysis (pH, titratable acidity, dry matter and colour), microbial analysis (total microorganism, Lactobacillus spp, Lactococcus spp. and yeast counts), total antioxidant activity (by ORAC method), total amount of phenolic contents and sensorial properties of all kefir samples were carried out at the 1st, 7th and 14th days of storage. Consequently, the results of pH, titratable acidity and dry matter in the kefir samples were determined to change between the values 4.11-4.39; 0.22-0.30 and 11.9-17.02% respectively, during the storage. In the colour analysis, the redness colour parameter of the kefir sample produced using molasses was determined to be higher compared to the other kefir samples. At the first day of storage, the total antioxidant contents of the control group kefir, plum- added kefir and molasses-added kefir samples were determined as 13.30; 16.80 and 17.35 µmol ml-1; and the total phenolic contents as 945.70; 2535.8 and 2357.6 mg ml-1, respectively. Content of total microorganism in kefir samples varied between 8.91-9.80 log kob ml-1during the storage period. Lactobacillus spp. and Lactococcus spp. contents of kefir produced using molasses were determined to have the highest values with 9.11 and 9.91 log kob ml-1, respectively, at the first day. Yeast content of the plum kefir and the molasses kefir samples including sugar was detected to be higher than that of the controlled kefir sample. According to the results of the sensory analysis, the kefir produced with plum was approved the most by the panelists. As a result of this study, two alternative products with quite high total phenolic content and antioxidant activity were developed for consumers.


2021 ◽  
Vol 12 (3) ◽  
pp. 2889-2904

The production of phytochemicals in plants can be influenced by several factors. This work evaluated the influence of seasonality on phytochemical composition, phenolic content, and antioxidant activity of Neoglaziovia variegata. The leaves were harvested for a year. Phytochemical characterization by thin-layer chromatography indicated the presence of anthocyanins, anthraquinones, anthracene derivatives, flavonoids, tannins, monoterpenes, diterpenes, triterpenes, and steroids in the leaves collected in all months, and coumarins in leaves of 4 of the 12 months of collection. The antioxidant activity, evaluated in vitro, ranged from 33.0 to 86.1% inhibition of DPPH• and from 36.2 to 97.8% inhibition of ABTS•+. The total phenolic content, determined using Folin-Ciocalteu reagent, varied between 21.5 and 65.8 mg GAE/g. Phenolic acids and flavonoids were determined by HPLC-DAD, with higher concentrations of kaempferol (0.47-3.57 mg/g), p-coumaric (0.19-3.59 mg/g) and ellagic (0.26-3.31 mg/g) acids. The Principal Component Analysis (PCA) indicated the separation of the leaf samples according to the season. It was demonstrated the influence of seasonality on the antioxidant activity and phytochemical composition of N. variegata leaves and that this species is rich in secondary metabolites of different classes, with potential applications in several areas, such as pharmaceutical and food.


Author(s):  
Hacer Gurkan ◽  
Osman Seracettin Boran ◽  
Ali Adnan Hayaloglu

Four different types of yoghurt were manufactured using purple basil which was added to milk as water extract or powder forms at levels of 1.0 % and 0.4 % (w/w). Physicochemical and rheological properties, antioxidant capacity, color and total phenolic contents of yoghurt samples were measured during 21 days of storage. None of changes were observed for titratable acidity, pH and hardness parameters of yoghurt samples; however, some changes were observed during storage. The contents for total phenolic compounds and antioxidant activity [2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS+*) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH*) values] were dramatically higher in powder-added yoghurt samples than those of its water extract counterparts, while the lowest total phenolics and ABTS+* were observed in control sample during storage. The values for storage and loss modulus were higher in water extract-added samples than powder-added counterparts. In conclusion, no significant effect of the addition of powder or water extract of basil was observed on gross chemical characteristics of yoghurt, while use of basil powder positively contributed to antioxidant activity and changed the rheological behavior of yoghurt gel.


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