scholarly journals Lipid yields of algae dried in an enhanced solar chimney

2021 ◽  
Vol 1195 (1) ◽  
pp. 012002
Author(s):  
L O Morris ◽  
C M Chu ◽  
E Suali
Keyword(s):  
Moisture Content ◽  
Biodiesel Production ◽  
Average Moisture Content ◽  
Drying Methods ◽  
Solar Chimney ◽  
Oven Drying ◽  
Sun Drying ◽  
Lipid Yield ◽  
Chlorella Sp ◽  
Low Energy Consumption

Abstract This work focuses on the lipid yield of algae dried using an enhanced solar chimney dryer with the aim towards high quality biodiesel production and low energy consumption. Jaworski’s medium was chosen for the cultivation in this research project as it can provide enough nutrients to green algae of type Chlorella. Sp. Centrifugation is an effective method to harvest the algae from its medium prior to a drying process. In this project, the methods used for drying were oven drying, open-sun drying and an enhanced solar chimney drying. The moisture content was determined where the average moisture content were 82.5% for oven drying method, 81.6% for open sun drying and 82.2% for solar chimney drying. Methods were found to affect differently the algae properties in terms of the lipid yield and mineral content. The lipid yields were 23.7%, for oven drying, 20.6% for open sun drying and 24.4% for enhanced solar chimney drying. While the oven drying was found to be the fastest way to dry the algae, the solar chimney drying proved best in energy saving while producing the same amount or more algae lipid within reasonable drying times.

scholarly journals Changes in Physicochemical Properties and Volatile Compounds of Roselle (Hibiscus sabdariffa L.) Calyx during Different Drying Methods

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6260
Author(s):  
Nurul Hanisah Juhari ◽  
Helle Jakobe Martens ◽  
Mikael Agerlin Petersen
Keyword(s):  
Moisture Content ◽  
Physicochemical Properties ◽  
Volatile Compounds ◽  
Freeze Drying ◽  
Cell Structure ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Oven Drying ◽  
Sun Drying ◽  
Freeze Dried

Fresh roselle are high in moisture and deteriorate easily, which makes drying important for extending shelf-life and increasing availability. This study investigated the influence of different drying methods (oven-drying, freeze-drying, vacuum-drying, and sun-drying) on the quality of roselle calyx expressed as physicochemical properties (moisture content, water activity, soluble solids, color), volatile compounds, and microstructure. Oven-drying and freeze-drying reduced moisture content most while vacuum-drying and sun-drying were not as efficient. All drying methods except sun-drying resulted in water activities low enough to ensure safety and quality. Vacuum-drying had no impact on color of the dry calyx and only small impact on color of water extract of calyx. Drying reduced terpenes, aldehydes, and esters but increased furans. This is expected to reduce fruity, floral, spicy, and green odors and increase caramel-like aroma. Sun-drying produced more ketones, alcohols, and esters. Scanning electron microscopy revealed that freeze-drying preserved the cell structure better, and freeze-dried samples resembled fresh samples most compared to other drying techniques. The study concludes that freeze-drying should be considered as a suitable drying method, especially with respect to preservation of structure.

Effects of Drying Methods on the Biochemical Composition and Organoleptic Properties of Two Freshwater Fish Species (Mormyrus rume and Labeo coubie) of Cross River Obubra, Nigeria

2019 ◽  
Vol 2 (1) ◽  
Keyword(s):  
Moisture Content ◽  
Fish Species ◽  
Nutrition Status ◽  
Drying Methods ◽  
Organoleptic Properties ◽  
Nutrient Quality ◽  
Oven Drying ◽  
Fish Samples ◽  
Fish And Fishery Products ◽  
Mormyrus Rume

Consumers all over the world are increasingly becoming aware of the health and nutrition status of fish and fishery products. There have develop some preference for fish species and even their processing methods. This study aims to investigate the effects of two drying methods (smoking and oven drying) on the biochemical components and organoleptic properties of two less preferred food fishes abundant in the study area. The fish samples Mormyrus rume and Labeo coubie were purchased from fresh landings of fishermen at Ahaha beach. The biochemical assay of the moisture, protein, fat, carbohydrate, ash, calcium (Ca), magnesium (Mg), phosphorus (P), iron (Fe), sodium (Na) and potassium (K) were conducted in the labouratory using standard methods. The proximate composition of raw M. rume was determined as moisture 70.38%, protein 17.43%, carbohydrate 1.13%, fat 5.93% and ash 2.77% while oven dried were 18.78, 63.85, 3.37, 8.73 and 7.58% respectively. All the proximate parameters and gross energy level investigated were higher (p < 0.05) in M. rume except the moisture content of dried samples of L. coubie. The mineral content were in the order Ca < Mg < Fe < Na < P and < K in both species and were higher in M. rume except Na. The drying methods showed increase in the proximate and mineral compositions in the order raw < smoking and < oven drying except moisture content that decreased respectively is both species. Organoleptic properties revealed that dried samples (smoked and oven) were not significantly different (p < 0.05) in taste, flavour, texture and overall acceptance, however while oven dried had better colour (4.33), smoked dried taste (4.63) better. The drying methods shows concentration of the required nutrients in human diets and were also found to be most palatable by the panellist. To improve fish nutrient quality smoke and oven drying should be encourage.

scholarly journals Cherry Tomato Drying: Sun versus Convective Oven

Horticulturae ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 40
Author(s):  
Vincenzo Alfeo ◽  
Diego Planeta ◽  
Salvatore Velotto ◽  
Rosa Palmeri ◽  
Aldo Todaro
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Drying Process ◽  
Drying Time ◽  
Oven Drying ◽  
Sun Drying ◽  
Different Temperatures ◽  
Final Water Content ◽  
Drying Curves ◽  
Drying Conditions

Solar drying and convective oven drying of cherry tomatoes (Solanum lycopersicum) were compared. The changes in the chemical parameters of tomatoes and principal drying parameters were recorded during the drying process. Drying curves were fitted to several mathematical models, and the effects of air temperature during drying were evaluated by multiple regression analyses, comparing to previously reported models. Models for drying conditions indicated a final water content of 30% (semidry products) and 15% (dry products) was achieved, comparing sun-drying and convective oven drying at three different temperatures. After 26–28 h of sun drying, the tomato tissue had reached a moisture content of 15%. However, less drying time, about 10–11 h, was needed when starting with an initial moisture content of 92%. The tomato tissue had high ORAC and polyphenol content values after convective oven drying at 60 °C. The dried tomato samples had a satisfactory taste, color and antioxidant values.

Effect of drying methods on the nutritional content and In- vitro Antioxidant capacity of Chenopodium album L. and Spinacia oleracea L.

2021 ◽  
pp. 4361-4366
Author(s):  
Sonia Singh ◽  
Neetu Agrawal
Keyword(s):  
Spinacia Oleracea ◽  
Chenopodium Album ◽  
Microwave Drying ◽  
Total Phenolic ◽  
Drying Methods ◽  
Drying Method ◽  
Nutrient Quality ◽  
Oven Drying ◽  
Sun Drying ◽  
Hot Air

The herbs, Chenopodium album Linn. and Spinacia oleracea Linn. belongs to Chenopodiaceae family, are the two nutritious and edible green leafy food crops, abundantly found especially in the northern-west region of India. These plants have gained renown popularity, because of their high nutritional content including protein, amino acids, carbohydrate, and even the presence of phenolic components, which ultimately may get affected with drying and storage techniques. Impact of different drying methods (microwave drying at 4 minutes, hot air oven drying at 5 hours and sun drying at 8-10 hours) on nutrient quality and antioxidant property of Chenopodium album Linn. and Spinacia oleracea Linn. leaves were evaluated by using UV spectrophotometritc assay, total phenolic content and DPPH free radical scavenger method. Drying treatments were significantly decreased the moisture, carbohydrate and protein content present in C.album and S. oleracea. Hot air oven drying method produced dried samples of C.album and S. oleracea had significantly similar antioxidant activity when compared with the samples obtained from sun drying method. The dried samples obtained from hot air oven drying technique showed significant presence of total phenolic content in C. album and S. oleracea (6.44±0.12 mg/g, 6.69±0.40 mg/g) whilst the traditional sun drying method produced 8.00±0.02 mg/g and 7.89±0.37 mg/g). It is concluded that microwave drying and hot air oven drying were the methods to preserve appreciable percentage of nutrient components compared to the fresh samples. On other hand, the traditional method produced substantial reduction of nutrient quality. From statistical analysis, hot air oven drying technique was considered as optimum method which showed satisfactory % retention of protein (65.86%) and carbohydrate (85.95%) at 5 hours (shorter time than sun drying time period) along with significant antioxidant activity (34.89 μg/mL and 35.60 μg/mL) similar as obtained from the traditional technique (32.00 μg/mL).

scholarly journals Pengaruh Dua Metode Pengeringan Pada Aktivitas Antibakteri Ashitaba (Angelica keiskei ) Terhadap Streptococcus mutans

2018 ◽  
Vol 4 (1) ◽  
pp. 18-25
Author(s):  
Dyke Gita Wirasisya ◽  
Yohanes Juliantoni ◽  
Wahida Hajrin
Keyword(s):  
Antibacterial Activity ◽  
Streptococcus Mutans ◽  
Total Phenolic Content ◽  
Phenolic Content ◽  
Total Phenolic ◽  
Drying Methods ◽  
Drying Method ◽  
Oven Drying ◽  
Sun Drying ◽  
Angelica Keiskei

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.

scholarly journals Development and performance evaluation of a solar tunnel date dryer in Oman

2012 ◽  
Vol 17 ◽  
pp. 21
Author(s):  
Mohammad Ali Basunia ◽  
Hamid H. Al-Handali ◽  
Mohammed Issa Al-Belushi ◽  
Mohammad Shafiur Rahman ◽  
Osman Maghoub
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Average Moisture Content ◽  
Air Velocity ◽  
Sun Drying ◽  
Tunnel Dryer ◽  
Moisture Content Level ◽  
Collector Region ◽  
And Performance

Taking into consideration the date harvesting and landholding capacities of the marginalized rural farmers in Oman, a 12 meter long and 2 meter wide tunnel was designed and constructed to dry about 180-200 kg of freshly harvested dates per batch. Half of the tunnel base was used as a flat plate air heating solar collector and the other half as a dryer. The drying air was forced from the collector region (South side) to the drying region (North side) of the half circled tunnel where the product is to be dried. The drying temperature could be easily raised by some 5-30 oC above the ambient temperature inside the tunnel at an air velocity of approximately 0.5 m/sec. The test was conducted with 190.2 kg freshly harvested dates with initial moisture content of 32.8% (wet-basis) to analyze the performance of the dryer. The dates were dried to a final average moisture content of 18.6% (wet-basis) within two days (20 hours). The results indicated that the drying was faster in a solar tunnel dryer than the natural open air sun drying. It was possible to reach the moisture content level for safe storage within less than two days (20 hrs) with a solar tunnel dryer and 5-7 days in open air natural sun drying. The improvement in the quality of dates in terms of color and brightness was distinctly recognized. 

scholarly journals Effects of Drying Methods and Onion Bulb Variety on Physicochemical and Functional Properties of Onion Powder

2021 ◽  
pp. 42-54
Author(s):  
Ayéméné Cédrick Ardin Koménan ◽  
Bio Sigui Bruno Bamba ◽  
Joëlle-Annabelle N’gouin ◽  
Marie Stella Hermance Akré ◽  
Yadé Réné Soro
Keyword(s):  
Moisture Content ◽  
Functional Properties ◽  
Water Solubility ◽  
Titratable Acidity ◽  
Drying Methods ◽  
Drying Process ◽  
Sun Drying ◽  
Allium Cepa L ◽  
Shelf Stable ◽  
Functional Components

Onion (Allium cepa L.) is a rich source of constituents that are beneficial to human health. However, the short shelf life of these vegetables are a major cause of postharvest losses during peak harvesting season. Drying is one of the most convenient technologies for shelf stable food products production. This study is aimed at assessing the effects of three drying methods (industrial oven, electric dryer and sun drying) on physicochemical (moisture content, ash content, pH, titratable acidity, total polyphenol contents) and functional properties (water solubility and particle sizes) of onion powders of two onion varieties (white and violet of galmi). From the results obtained, physicochemical and functional components are affected significantly (P<0.05) by drying process but not titratable acidity (to the order of 36 mEq/100g DM). In addition, the moisture content of onion powders were below 13.66±0.115, 14.73±0.115, 14.60±0.305 g/100g WM for industrial oven, electric dryer and sun drying respectively with pH between 3.29 and 5.16. In addition, these powders showed a small particle size (under 400 μm) and high solubility as 93.33±2.3, 72±0.5, 62.66±2.3 g/100 g DM for Electric dryer (ED), Industrial oven (IO) and Sun drying (SD) respectively. Furthermore, polyphenol content was almost different in all the different drying process with values between 721.32 to 962.26 mg GAE/100g DM. Moreover, all properties were varied significantly (P<0.05) between white and violet of galmi powders. The preferred drying method and onion variety were industrial oven and violet of galmi. Finally, these results could be a valorization way to promote an industrialization of onion powders.

scholarly journals The effect of different drying methods on non-volatile and volatile components and immunomodulatory activity of Osmamthus fragrans flowers

2020 ◽  
Author(s):  
Yuexing Chang ◽  
Junjie Lin ◽  
Siqing Pan ◽  
Yanlin Jing ◽  
Ailing Guo ◽  
...  
Keyword(s):  
Microwave Drying ◽  
Chemical Components ◽  
Immunomodulatory Activity ◽  
Volatile Components ◽  
Drying Methods ◽  
Drying Method ◽  
Quick Lime ◽  
Oven Drying ◽  
Sun Drying ◽  
Linalool Oxide

Abstract Background: Osmamthus fragrans (O. fragrans) has high ornamental, edible and medicinal value in China. The components of its flowers have been gradually revealed, but the active ingredients with immunoregulatory activity have been unknown. Also, it needs to be studied that which groups and drying methods can make O. fragrans fowers produce more immunomodulatory activity. This study aimed to investigate the effects of drying methods on non-volatile and volatile components of O. fragrans flowers from three groups, and to further explore if their groups and drying methods had an ovious effect on their immunoregulatory activity.Methods: O. fragrans flowers from three groups such as “Aurantiacus”, “Latifolius” and “Thunbergii” were dried with shade drying, sun drying, quick-lime drying, oven drying and microwave drying method, respectively. The non-volatile components such as salidroside, verbascoside, oleanolic acid and ursolic acid and volatile components such as linalool, linalool oxide, geraniol, α-ionone and β-ionone of O. fragrans flowers above were determined by high-performance liquid chromatography (HPLC) and gas chromatography (GC), respectively. The immunomodulatory activities of chemical components above were investigated by the neutral red uptake assay.Results: There are more non-volatile components and less volatile components in O. fragrans flowers from Aurantiacus group and Latifolius group than Thunbergii group. Microwave drying and oven drying at high temperature were beneficial for the preservation of the bioactive non-volatile components for killing enzyme and protecting glycoside. Other drying methods such as shade drying, sun drying, quick-lime drying and oven drying at low temperature were beneficial to their preservation of the fragrant volatile components. Salidroside, verbascoside, linalool, and linalool oxide had the better immunoregulatory activity than other ingredients. In addition, non-volatile components played a more important role in the contribution to the immunoregulatory activity than the volatile components as the former was almost 1000 times as much as the latter. Conclusions: O. fragrans flowers from Aurantiacus group with microwave drying (high fire) method had the best immunoregulatory activity. The research could provide some evidence in choosing drying method of O. fragrans flowers as food or medicine.

scholarly journals Effect of Drying Methods and Packaging on the Nutritional Values of Onions (Allium cepa L.) Bulbs

2020 ◽  
pp. 47-55
Author(s):  
Elizabeth Toyin Afolabi ◽  
Vadlya Tizhe Tame
Keyword(s):  
Allium Cepa ◽  
Research Work ◽  
The Other ◽  
Drying Methods ◽  
Plastic Container ◽  
Physiochemical Properties ◽  
Oven Drying ◽  
Sun Drying ◽  
Onion Bulbs ◽  
Other Hand

This research work was designed to give an insight on physiochemical properties of Allium cepa. The purpose of this study was to determine the effects of three drying methods on the physiochemical properties of onion bulbs and to determine the effective packaging material on the physiochemical properties of onion. Freshly harvested onion bulbs at a fully matured stage and fully ripe was purchased from a commercial farm at Locco farms from Song LGA of Adamawa State, Nigeria. The experiment consists of six treatments which include oven drying plastic container, oven drying polythene bags, sun drying plastic container, sun drying polythene bags, shade drying plastic container and shade drying polythene bags. The experiment was replicated three (3) times and data was collected on parameters such as color, bulk density, fat, carbohydrate and, fiber. The various drying methods used were capable of preserving the nutrients in A. Cepa without total loss of any nutrient. Shade dried and oven dried samples were found to be more nutritive, on the other hand, oven drying and sun drying were faster in drying than the shade drying method. Oven drying was more cost effective and gave the lowest moisture content in this study, suggesting higher capacity to prevent microbial growth and decay in the dried samples, thus confers a greater increase in shelf-life on the dried samples. On the other hand, plastic container packaging was found to be better in terms of maintaining physical and chemical properties of the dried samples followed, by polythene bags. Further study should be carried out on the factors that affect the storability of onion bulbs in both dried and fresh samples.

scholarly journals The Effect of Sugar Cane Levels and Drying Methods on Chemical and Physical Qualities of Ground Beef “Dendeng”

2018 ◽  
Vol 42 (1) ◽  
Author(s):  
Jamhari Jamhari ◽  
Edi Suryanto ◽  
Sundari Sundari ◽  
Diah Ayu Laksmiwati
Keyword(s):  
Protein Content ◽  
Sugar Cane ◽  
Ph Value ◽  
Ground Beef ◽  
Cane Sugar ◽  
Drying Methods ◽  
Physical Quality ◽  
Oven Drying ◽  
Sun Drying ◽  
Randomized Design

This study was conducted to investigate the effect of sugar cane levels and drying methods on chemical and physical quality of ground beef “dendeng”. The materials were ground beef, cane sugar, and spices consisting of salt, garlic, coriander, and galangal. The treatments were the sugar cane levels, consisting of 20, 30, and 40% (w/w of meat weight), and the drying methods, consisting of oven drying and sun drying. The oven drying was done at 50+20C for 15 hours, while sun drying was done at 40+20C for 6 hours per day for 4 days. The variables were tested on chemical quality (moisture, protein, and fat contents), and physical quality (pH and tenderness). Data were analyzed by analysis of variance of factorial pattern (3x2) of completely randomized design and continued by Duncan's new multiple ranges test. The results showed that there was an interaction between the sugar cane levels and the drying methods on the protein content and tenderness of ground beef “dendeng” (P<0.01). Sugar cane levels had significant effects on protein content and tenderness (P<0.05), but had no significant effect on moisture content, fat content, and pH value of ground beef “dendeng”. The drying methods had no significant effect on all chemical and physical variables of ground beef “dendeng”. In conclusion, there was an interaction between sugar cane levels and drying methods  on the protein content and tenderness of ground beef “dendeng”. The addition of sugar cane at the levels of 40% yielded ground beef “dendeng” with the best tenderness. However, the methods of drying did not affect the chemical and physical qualities of ground beef “dendeng”.

Sign in / Sign up

Export Citation Format

Share Document