scholarly journals Comparison of Different Drying Methods and Preservatives on the Proximate Composition, Colour and Total Phenolic Content of Dried Ginger.

2020 ◽  
Vol 11 (1S) ◽  
Author(s):  
Nurhidayah Hanim Mohamad ◽  
Asmaliza Abd Ghani ◽  
Nurul Zaizuliana Rois Anwar ◽  
Norzaida Yusof ◽  
Yusof Nurhayati

The present work proposed to compare three different drying methods i.e. sun drying, vacuum oven drying and freeze drying of ginger to determine the proximate composition, colour analysis and total phenolic content. These dried gingers were preserved by using sugar (control), Tualang honey and Kelulut honey. It showed that freeze dried ginger presents the best result for retaining nutrients, colour and total phenolic content compared to other drying methods. For colour analyses, sun dried samples resulted in the lowest value of L* were 50.94, 51.24 and 52.22 for control, Tualang honey and Kelulut honey due to longer drying time and oxygen exposure. Among all preservatives used, Tualang honey produced the best quality of dried ginger as the highest total phenolic content was 26.73 mg gallic acid/g.

2018 ◽  
Vol 46 (2) ◽  
pp. 449-456 ◽  
Author(s):  
Hacer COKLAR ◽  
Mehmet AKBULUT ◽  
Semih KILINC ◽  
Ali YILDIRIM ◽  
Iliasu ALHASSAN

Flowers, leaves and fruits of hawthorn plant are traditionally used for treating diseases like hypertension and atherosclerosis. The medicinal effects of the plant are generally attributed to its phenolic compounds. However, the fruits are perishable materials because of their high content of water, and generally dried and stored to be used outside its season. The main aim of this research was to investigate the effect of different drying methods on phenolic compounds of the hawthorn fruit. Fruits were collected from the wild growing trees in Turkey. De-seeded fruits were dried in freeze-, oven- (60 oC) and microwave pretreated oven drying (microwave application for 5 min at 360 W before drying at 60 oC) methods and analyzed for antioxidant activity, phenolic compounds, total phenolic content and color parameters. Total phenolic content of fresh hawthorn fruits was found as 13.36 mg g-1 DW. Oven- and microwave pretreated oven drying methods had a reductive effect on total phenolic content and antioxidant activity of fruits when compared to freeze drying method. (-)-Epicatechin (994.10 mg kg-1 DW), rutin (765.30 mg kg-1 DW), and procyanidin B2 (553.80 mg kg-1 DW) were the main phenolics of the fruit. Lowest values of these three compounds were observed in oven-dried fruits. Microwave pretreatment oven drying method resulted in browner product. Although the highest phenolic concentration and antioxidant activity were occurred in freeze-dried sample, microwave pretreatment before oven drying could be applied to reduce the time and cost of drying in terms of phenolic compounds and antioxidant activity.


Fermentation ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 301
Author(s):  
Jurgita Kulaitienė ◽  
Nijolė Vaitkevičienė ◽  
Dovilė Levickienė

Yogurt products are consumed by millions of people every day. Consumers’ priority for ready-to-eat yogurt snacks enriched with various plant raw materials have increased each year. Therefore, the aim of this study was to prepare freeze-dried yoghurt bites with the addition of powders of beetroot, mulberry leaves, nettle leaves and rosehip fruit and to investigate these raw materials’ influence on the proximate composition, mineral and total phenolic content. The moisture, protein, fat, carbohydrate and sugar content of the yogurt bites were established using standard methods: mineral composition—using an inductively coupled plasma mass spectrometer (ICP-MS); total phenolic content—by the spectrophotometric method. The results demonstrated that the addition of different raw material powders to the formulation of yogurt bites had no significant influence on carbohydrate, protein and total fat amounts. However, the incorporation of powders of beetroot, mulberry leaves, nettle leaves and rosehip fruit in yogurt bites allowed a significant increase of the amounts of all investigated minerals and total phenolic content of the manufactured bites. Among all investigated yogurt bites, the highest amounts of K, P, Mg, Fe and Zn were determined for yogurt bites enriched with nettle leaves. In conclusion, the enrichment of yogurt bites with freeze-dried plant raw material powders can increase amounts of selected minerals and total phenolic content.


2021 ◽  
Vol 8 (2) ◽  
pp. 108-113
Author(s):  
Syaliza Omar ◽  
Noor Marinah Sahri ◽  
Hafizah Abd. Aziz ◽  
Maimunah Sanny

The effect of temperature at 50°C, 70°C and 100°C for up to 120 min on the content of phenolic compounds and antioxidant activity of Tualang honey and Kelulut honey was studied. Unheated honey samples for both varieties were used as control. The total phenolic content and antioxidant activity were examined using Folin-Ciocalteau and DPPH assays, respectively. Both honeys vary widely in the total phenolic content as well as antioxidant activity upon heating and time of heating. The total phenolic content in both honeys showed fluctuations at all temperatures throughout 120 min. In comparison to controls for both honeys, heating at 100°C for 10 min demonstrated a drop in total phenolic content in Tualang honey (13%) and Kelulut honey (29%), but the antioxidant activity increased 29% and 57% in Tualang and Kelulut honey, respectively. The study generates information on the characteristics of components in both honeys which react differently to heat and time of heating, therefore this will help the honey manufacturers or public to optimize the processing protocols and later to preserve the quality of honey.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 226
Author(s):  
Katarzyna Rybak ◽  
Artur Wiktor ◽  
Dorota Witrowa-Rajchert ◽  
Oleksii Parniakov ◽  
Małgorzata Nowacka

It has been demonstrated previously in the literature that utilization of PEF or a combination of a pulsed electric field (PEF) and ultrasounds (US) can facilitate dehydration processes and improve the quality of dried products even better than the application of thermal methods such as blanching. The aim of the study was to evaluate the quality of red bell pepper subjected to freeze-drying preceded by blanching or PEF or US treatment applied in a single and combined mode. Furthermore, the freeze-drying was preceded by shock freezing or vacuum freezing performed inside the freeze-dryer as a result of pressure drop during the first stage of freeze-drying. All of the analyzed technological variants enhanced the drying kinetics when compared to the intact material. Freeze-dried bell pepper subjected to non-thermal pretreatment exhibited higher vitamin C, total phenolic and carotenoids content than blanched material despite the fact that blanching reduced drying time the most compared to all other analyzed methods.


Fermentation ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 48
Author(s):  
Bing Zhou ◽  
Zhao Jin ◽  
Paul Schwarz ◽  
Yin Li

The phenolic content and antioxidant potential of malting barley are important in brewing. The objective of our study was to investigate the effects of barley genotype, growing environment, and malting conditions on the total phenolic content and antioxidant activities of malting barley grown in North America. Eight barley cultivars grown at three locations over three years were used. For the malting study, a single barley cultivar, separated into different kernel size fractions, was germinated for various periods of time and then processed by kilning or freeze-drying. Total phenolic content (TPC) and some of the antioxidant activities, including DPPH, ABTS, and superoxide anion radical scavenging activities, reducing power, and iron (II) chelating activity, were significantly impacted by the barley genotype, growth environment, and their interactions. The TPC and most antioxidant activities were also influenced by malting conditions and were generally higher in the malted barleys of the thin kernel size fraction, four-day germination, and in samples processed by kilning, when compared to the plumper kernel size fractions, one and two days of germination, and freeze-dried samples, respectively. There were interactions between malting parameters, and stepwise regression analysis was used to suggest the contribution of each parameter to the TPC and antioxidant activities.


2014 ◽  
Vol 4 (2) ◽  
pp. 68 ◽  
Author(s):  
Umesh C. Lohani ◽  
Kasiviswanathan Muthukumarappan

Although extrusion is a promising process to develop ready to eat cereals and snacks, thermal treatment to raw material during extrusion results in degradation of phenolic compounds. Therefore, an approach was made to enhance the total phenolic content (TPC) and antioxidant activity (AA) of apple pomace (AP) prior to extrusion process. In this study, AP powder was naturally fermented (F) for 12 h and then was subjected to ultrasonication (U) at various conditions [25, 37, and 50 µm ultrasonication amplitude (UA) for 1, 2, and 3 min of ultrasonication time (UT)]. AP was then dried in oven (O) and microwave (MW), separately and thus four drying methods, i.e. O<sub>F</sub>-O<sub>U</sub>, O<sub>F</sub>-MW<sub>U</sub>, MW<sub>F</sub>-O<sub>U</sub>, MW<sub>F</sub>-MW<sub>U</sub> were used in combinations. Full factorial design was used for experimental plan and results were analyzed using statistical software. It was observed that drying method significantly affected the TPC and AA of AP powder followed by UA. UT did not have any significant effect on TPC, and AA. Maximum TPC, and AA observed for the AP powder dried in MW after fermentation and ultrasonication (MW<sub>F</sub>-MW<sub>U</sub>) at 50 µm UA for 3 min UT were 372.98 mg GAE/100g DW, and 729.67 µmol TE/100 g DW, respectively. MW<sub>F</sub>-MW<sub>U</sub> drying exhibited a more prominent disrupted and porous structure of AP powder compared with that of O<sub>F</sub>-O<sub>U</sub> drying.


2014 ◽  
Vol 548-549 ◽  
pp. 96-100
Author(s):  
Shareena Fairuz Abdul Manaf ◽  
Nur Shahidah Ab Aziz ◽  
Syawal Abdullah ◽  
Rafeqah Raslan ◽  
Fazlena Hamzah ◽  
...  

Pereskia Bleois commonly used among the local traditional medicine practitioners to prevent or treat cancer by consuming the leaves either raw or taken as a concoction brewed from fresh leaves. However, more research, regulation and standardization are required before herbal medicines can be recommended as effective and safe therapies. The objectives of this study are to obtain the optimum drying parameter and to identify the concentrations of phenolic content expressed as gallic acid equivalents (GAEs) inPereskia bleoleaves. Pareto ANOVA method was used to study the optimum condition and the total phenolic content via F-Test using three samples for variance and three-factor with replication. Taguchi ANOVA was performed using SN ratio with L9 orthogonal array to accommodate the three factor level. The drying time were tested for 3 hours, 4 hours and 5 hours. The result shows that drying time is the significant factor in drying process and followed by drying temperature and solvent volume used. The drying experiments were conducted at operating temperature of 35 °C, 40 °C and 45 °C. While the extraction were conducted at different volume using methanol of 150 ml, 180 ml and 200 ml. The standard curve of total phenolic content was based on the gallic acid compound. The total phenolic content in C2 was at the most suitable for being used as antioxidant for consumption in human body with drying time of 5 hours at 45 °C by using 180 ml of methanol for extraction ofP.bleoleaves.


Author(s):  
Dyke Gita Wirasisya ◽  
Yohanes Juliantoni ◽  
Wahida Hajrin

The aim of this study was to determine a change that occurs in total phenolic content (TPC) and antibacterial activity of ashitaba (Angelica keiskei) after dried using two different methods : sun and oven drying. The effectiveness of the drying methods was evaluated in term of total phenolic content (TPC) by using spectrophotometric assay with Folin-Ciocalteu reagent and antibacterial activity againts Streptococcus mutans by in vitro macrodilution assay. Oven drying at 60oC possessed high TPC (2,98 ± 0,0935 g EAG/100g) compared to sun drying method (1,72 ± 0,0142 g EAG/100g). Simillar pattern was also observed in antibacterial activity. Oven drying have higher antibacterial activity with the MBC (minimal bactericidal concentration) value of 0,5 mg/mL againts Streptococcus mutans. Therefore, sun drying is not suggested for drying method of ashitaba in terms of total phenolic content and antibacterial activity compared with oven drying methods.


2021 ◽  
Vol 913 (1) ◽  
pp. 012042
Author(s):  
N Ardiana ◽  
A S Abidin ◽  
B T K Ilhami ◽  
A L Sunarwidhi ◽  
S Widyastuti ◽  
...  

Abstract Seaweed is one of the marine-biota that is widely known for its uses, one of them is in the food functional. Functional food is a program that promotes a healthy diet so that it can prevent a disease when consuming food. With functional food, daily eating patterns can be maintained and also the content of the food consumed daily has a good effect on the body. It is known that in seaweed, especially brown algae (S. crassifolium), it contains antioxidants and other compounds that are good for the health. In this study, phytochemical content and proximate composition was evaluated in S. crassifolium. Including total flavonoid content and total phenolic content, antioxidant capacity both of DPPH and ABTS assay used three type of solvents such as Ethanol, n-Hexana, and ethyl acetate for comparable the best solvents. Also, proximate analysis to determine the content of moisture content, crude fat content, crude protein content, and carbohydrates content. The results showed that n-Hexana and ethyl acetate solvents were significantly than ethanol. Which mean both of them had highest values of total flavonoid content (TFC), total phenolic content (TPC), and antioxidant activity of DPPH radical scavenging activity and ABTS radical scavenging activity. The results of chemical composition in proximate compounds showed that S. crassifolium was suitable to be candidate of functional food.


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