scholarly journals Variation in the Physical and Functional Properties of Yam (Dioscorea spp.) Flour Produced by Different Processing Techniques

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1341
Author(s):  
Nurdi Setyawan ◽  
John Solomon Maninang ◽  
Sakae Suzuki ◽  
Yoshiharu Fujii
Keyword(s):  
Functional Properties ◽  
Freeze Drying ◽  
Total Phenolics ◽  
Oven Drying ◽  
Browning Reaction ◽  
Freeze Dried ◽  
Yam Flour ◽  
Phenolics Content ◽  
Dioscorea Bulbifera ◽  
Processing Techniques

Research on the processing of yam (Dioscorea spp.) into flour is aimed at optimizing techniques to obtain a material with high physicochemical and functional properties. The present study investigates the effect of the processing techniques on the levels of inulin, organic acids, total phenolics (TP), antioxidant capacity, and polyphenol oxidase (PPO) and peroxidase (POD) activities, as well as on the physicochemical properties of flour derived from two yam species—Dioscorea esculenta and Dioscorea bulbifera. All tubers were peeled and sliced, then subjected to different processing techniques through blanching, soaking, and drying. The results revealed that freeze-drying appears to be the best technique in achieving the highest whiteness index of yam flour. This coincided well with the low phenolics content and POD activity, which suggests a reduced enzymatic browning reaction in the freeze-dried yam flour. On the other hand, chemical analyses showed that D. esculenta and D. bulbifera flours have the highest levels of inulin (23.0 and 27.8 g/100 g DW, respectively) and succinic acid (7.96 and 7.65 g/100 g DW, respectively) in the samples subjected to direct oven-drying. Oven drying without pretreatment neither blanching nor water steeping maintained antioxidant activity in the flour derived from both D. esculenta and D. bulbifera.

scholarly journals Simulation of the process kinetics and analysis of physicochemical properties in the freeze drying of kale

2018 ◽  
Vol 32 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Dariusz Dziki ◽  
Renata Polak ◽  
Stanisław Rudy ◽  
Andrzej Krzykowski ◽  
Urszula Gawlik-Dziki ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Freeze Drying ◽  
Total Phenolics ◽  
Drying Time ◽  
Browning Index ◽  
Drying Temperature ◽  
Freeze Dried ◽  
Hue Angle ◽  
Phenolics Content ◽  
Kinetics Of

AbstractInvestigations were performed to study the freeze-drying process of kale (Brassica oleraceaL. varacephala). The process of freeze-drying was performed at temperatures of 20, 40, and 60°C for whole pieces of leaves and for pulped leaves. The kinetics of the freeze-drying of both kale leaves and kale pulp were best described by the Page model. The increasing freeze-drying temperature from 20 to 60°C induced an approximately two-fold decrease in the drying time. Freeze-drying significantly increased the value of the lightness, delta Chroma, and browning index of kale, and had little influence on the hue angle. The highest increase in the lightness and delta Chroma was observed for whole leaves freeze-dried at 20°C. An increase in the drying temperature brought about a slight decrease in the lightness, delta Chroma and the total colour difference. Pulping decreased the lightness and hue angle, and increased browning index. Freeze-drying engendered a slight decrease in the total phenolics content and antioxidant activity, in comparison to fresh leaves. The temperature of the process and pulping had little influence on the total phenolics content and antioxidant activity of dried kale, but significantly decreased the contents of chlorophyllaand chlorophyllb.

scholarly journals Effect of Supplementation of Dried Bioflocs Produced by Freeze-Drying and Oven-Drying Methods on Water Quality, Growth Performance and Proximate Composition of Red Hybrid Tilapia

2022 ◽  
Vol 10 (1) ◽  
pp. 61
Author(s):  
Tarq Binalshikh-Abubkr ◽  
Marlia Mohd Hanafiah
Keyword(s):  
Water Quality ◽  
Body Composition ◽  
Growth Performance ◽  
Freeze Drying ◽  
Energy Levels ◽  
Fish Growth ◽  
Drying Methods ◽  
Oven Drying ◽  
Freeze Dried

Supplementation of dried bioflocs for red hybrid tilapia (Oreochromis sp.) was examined during 57 days of feeding trials. Five experimental treatments; T1 (the control; without bioflocs), T2 (4% freeze-dried bioflocs), T3 (16% freeze-dried bioflocs), T4 (4% oven-dried bioflocs), and T5 (16% oven-dried bioflocs) were prepared to examine the water quality, growth performance and body composition of red hybrid tilapia. T2 and T4 treatments resulted in a higher growth rate and survival similar to the control, while T3 and T5 treatments showed the lowest values of growth performance among all treatments. T1 treatment showed the best quality of culture water followed by T2 and T4 treatments, while T3 treatment resulted in poor water quality followed by T5 treatment. Based on these results, the ratios of bioflocs (4% and 16%) had more effect on fish growth and water quality than the drying methods (freeze-drying and oven-drying). The ratio of 4% freeze-dried or oven-dried bioflocs provided higher growth rates and better water quality parameters similar to the control, while the ratio of 16% showed the worst growth performance and water quality in the present study. In addition, body compositions of tilapia fed 4% dried bioflocs showed better nutritional value than tilapia fed 16% dried bioflocs. Protein and energy levels showed an increasing trend with decreasing supplement levels of bioflocs. Moisture content was significantly higher when supplementation of 16% bioflocs was used. Overall, supplementation of 4% freeze-dried or oven-dried bioflocs can be successively included in red hybrid tilapia diets without any effects on growth or body composition and can result in a good quality of culture water for red hybrid tilapia.

scholarly journals Production of Attieke by the Technique of Drying of Cassava Ferment

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Koffi Maïzan Jean-Paul Bouatenin ◽  
Kohi Alfred Kouame ◽  
N’dédé Theodore Djeni ◽  
N’guessan Ghislain Koffi ◽  
Koffi Marcellin Dje
Keyword(s):  
Cote D'ivoire ◽  
Freeze Drying ◽  
Côte D’Ivoire ◽  
Drying Process ◽  
Cote D’Ivoire ◽  
Oven Drying ◽  
Côte D'ivoire ◽  
Large Numbers ◽  
Freeze Dried ◽  
Drying Techniques

The long-term availability of cassava ferment and the production of attieke of healthy and consistent quality are becoming serious problems in Côte d’Ivoire. The overall objective of this work was to assess the effect of several drying techniques on the performance of the traditional cassava ferment with a view to establishing a stabilized ferment for the production of attieke in Côte d’Ivoire. To do this, three drying techniques were used, namely, oven drying, sun drying, and freeze-drying. The end of the drying process is marked by the stabilization of the humidity rate of the ferment. The results obtained during the drying process indicate that the sun-dried ferment contains more GAM (1.2 ± 0.2) × 108 CFU/g than the other dried ferments. The freeze-dried ferment has the highest load of lactic acid bacteria (3 ± 0.2) × 105 CFU/g, while Bacillus was observed in large numbers in the ferment dried at 45°C (7.1 ± 0.6) × 105 CFU/g. The 37°C dried and freeze-dried cassava ferments recorded high yeast loads of (7.6 ± 0.5) × 104 CFU/g and (7 ± 0.4) × 104 CFU/g, respectively. Moulds ((5 ± 0.2) 1 × 102 CFU/g) were only detected in the 37°C dried culture. Moreover, during the fermentation of the cassava dough with the different ferments obtained after drying, a significant acidification occurs in the dough inoculated with the freeze-dried ferment (2.9 ± 0.07%). However, the attieke produced with the freeze-dried ferment and the ferment dried at 37°C was the most appreciated by the panelists. Thus, freeze-drying and oven drying at 37°C are simple alternatives to the use of traditional ferments that can ensure their stability and the conservation of the cassava ferment over a long period of time.

scholarly journals Proximate Analysis of Goat Milk Yogurt Powder Produced by Freeze Drying and Vacuum-Oven Drying and in Comparing with Freeze-Dried Yogurt Powder Prepared with Tualang Honey

2021 ◽  
Vol 12 (1S) ◽  
pp. 101-111
Author(s):  
Siti Norhannani Ahmat Azemi ◽  
Norshafiqah Zainul ◽  
Asmaliza Abd. Ghani ◽  
John Tang Yew Huat
Keyword(s):  
Moisture Content ◽  
Protein Content ◽  
Freeze Drying ◽  
Ph Value ◽  
Goat Milk ◽  
Drying Method ◽  
Vacuum Oven ◽  
Oven Drying ◽  
Freeze Dried ◽  
Tualang Honey

This study was carried out to produce powdered yogurt from goat milk with longer shelf life.Two methods of drying process of yogurt were used which are vacuum-oven drying (VD) and freezedrying (FD). Goat milk yogurt powder prepared with added Tualang honey (TH) was produced by freeze-drying method. In this study, four formulations of yogurt were prepared with the addition of commercial yogurt containingas starter culture.Granulated sugar was added about 8% into the yogurt as control sample. While other three yogurts were prepared with 8% of Tualang honey, 6% of Tualang honey with 2% of sugar and 4% of Tualang honey with 4% of sugar. The proximateanalysis was used in order to identify the proximate composition and pH value of the yogurt. The moisture content of goat milk yogurt, VD goat yogurt powder and FD goat yogurt powder were 79.20%, 8.22% and 9.66% respectively. While, the moisture content for FD goat yogurt powder with addition of 4%, 6% and 8% Tualang honey were 15.12%,15.92% and 13.53% respectively.While the value of ash content for FD goat milk yogurt powder with addition of 4%, 6% and 8% Tualang honey were 0.37%, 0.35% and 0.50% respectively. The total protein content for goat milk yogurt was 4.61% whilein VD goat yogurt powder and FD goat yogurt powder were 15.04% and 15.07% respectively. The value of protein content for FD goat milk yogurt powder with addition of 8% of Tualang honey was 15.38%. The pH value ofgoat milk sample and fresh yogurt goat milk were 6.52 and 3.82. The pH values for fresh yogurt with addition of 4%, 6% and 8% of Tualang honey were 4.64, 4.68 and 4.73.Vacuum-oven drying method and freeze-drying method did not show any significant different in moisture, ash and protein content but showed significant different in pH value.

scholarly journals Effect of Freeze-drying and Oven-drying Methods on Flavonoids Content in two Romanian Grape Varieties

2019 ◽  
Vol 70 (2) ◽  
pp. 491-494
Author(s):  
Lacramioara Oprica ◽  
Radu Gheorghe Antohe ◽  
Andreea Verdes ◽  
Marius Nicusor Grigore
Keyword(s):  
Freeze Drying ◽  
Drying Methods ◽  
Drying Method ◽  
Vacuum Oven ◽  
Oven Drying ◽  
North East ◽  
Freeze Dried ◽  
Red Grape ◽  
Grape Varieties ◽  
Fresh Skin

The aims of this work was to investigate the effect of thermal drying method (vacuum oven drying), and nonthermal drying method (freeze drying) on the flavonoids content in two red grape varieties (Cabernet Sauvignon and Merlot) from different grape components (seed, skin, and pulp) collected from two experimental fields, Bucium and Copou (North East of Romania). In general, the fresh skin of Cabernet and Merlot varieties has the highest flavonoids content followed by those obtained by oven-drying and freeze-drying process. A similar situation was observed in the other component of grape varieties like pulp and seeds meaning in the way that the flavonoid content in oven-dried samples were higher than that in the freeze-dried samples. In addition, from both varieties, Merlot collected from Bucium presented the highest content compared with Cabernet.

scholarly journals Effects of drying methods on the physicochemical properties and antioxidant capacity of Kuini powder

2021 ◽  
Vol 24 ◽  
Author(s):  
Gan Wei Shuen ◽  
Lew Yan Yi ◽  
Thor Sing Ying ◽  
Germaine Chng Yu Von ◽  
Yus Aniza Binti Yusof ◽  
...  
Keyword(s):  
Freeze Drying ◽  
Colour Change ◽  
Carotenoid Content ◽  
Total Phenolic ◽  
Drying Methods ◽  
Vacuum Oven ◽  
Oven Drying ◽  
Convection Oven ◽  
Total Carotenoid Content ◽  
Freeze Dried

Abstract Kuini powders were obtained through spray-drying, freeze-drying, vacuum oven drying and convection oven drying. Colour, water activity (Aw), moisture content, hygroscopicity, wettability, flowability, degree of caking, water solubility index (WSI), total colour change, total phenolic content and total carotenoid content of Kuini powders were determined and compared. Convection oven drying resulted in the highest yield (46.97%), moisture content (4.91%), Aw (0.55) and WSI (74.33%) among all the drying methods. However, convection oven-dried Kuini powder had the lowest hygroscopicity and wettability, which were 18.66% and 12.04 s, respectively. Spray drying resulted in poor hygroscopicity (22.41%), degree of caking (22.16%), wettability (275s), WSI (45.67%) and higher colour change (59.81). Least total colour change (19.05) and higher yellowness (57.31) were observed in freeze-drying. In addition, freeze-dried Kuini powder had the highest total phenolic content (24.76 mg/100 g) and total carotenoid content (1.61 mg/100 g). Drying temperature had a negative and significant correlation with the retention of color pigments and antioxidant content. The physicochemical properties and antioxidant content of freeze-dried Kuini powder were preferred over spray-dried, vacuum oven-dried and convection oven-dried powders. Hence, freeze-drying offers potential application in the food products.

Impact of processing on enzymatic browning and texturization of yellow mealworms

2019 ◽  
Vol 5 (4) ◽  
pp. 267-277 ◽  
Author(s):  
L. Tonneijck-Srpová ◽  
E. Venturini ◽  
K.N.P Humblet-Hua ◽  
M.E. Bruins
Keyword(s):  
High Pressure ◽  
Product Development ◽  
Freeze Drying ◽  
High Pressure Processing ◽  
Enzymatic Browning ◽  
Alternative Protein ◽  
Freeze Dried ◽  
Food Applications ◽  
Inactivation Process ◽  
Processing Techniques

The potential of Tenebrio molitor as an alternative protein source for food applications was investigated by using several conventional (blanching and freeze drying) and non-conventional (high pressure) processing techniques. Some of the challenges in product development are the browning effect of minced mealworms and the texturizing capacity after mincing. Both blanching and high pressure processing at 400 and 500 MPa proved to be effective in inactivating enzymes responsible for browning. However, the inactivation process was accompanied by a significant decrease in texturizing properties of the minced mealworms, especially when blanching was applied. Also when applying pressure, the texture changed from stronger (samples treated at lower pressures) to weaker (samples treated at higher pressures). Minced fresh or freeze dried mealworms provided textures with a reasonable strength and elasticity, but browning still occurred. Nevertheless, this browning could be slowed down by applying air tight packaging to prevent oxidation.

scholarly journals The Effect of Different Drying Methods on Primary and Secondary Metabolites in Korean Mint Flower

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 698
Author(s):  
Chang Ha Park ◽  
Hyeon Ji Yeo ◽  
Chanung Park ◽  
Yong Suk Chung ◽  
Sang Un Park
Keyword(s):  
Amino Acids ◽  
Secondary Metabolites ◽  
High Performance ◽  
Freeze Drying ◽  
Sinapic Acid ◽  
Drying Methods ◽  
Oven Drying ◽  
Primary And Secondary Metabolites ◽  
Freeze Dried ◽  
Β Carotene

Edible flowers have been used in the food and beverage industries because of their high nutritional value, flavor, and scent. For the storage of edible flowers used in these industries, drying is a necessity to store the materials more easily and prevent the damage of metabolites in the flowers. However, drying may affect metabolite retention because drying conditions can differ according to the various methods. In this study, Agastache rugosa flowers were dried using four different methods (oven drying at 25 ± 1 °C, 50 ± 1 °C, 80 ± 1 °C, and freeze drying) and primary and secondary metabolites were analyzed using high-performance liquid chromatography (HPLC) and gas chromatography time-of-flight mass spectrometry (GC-TOF/MS). Freeze-dried flower samples contained higher levels of carotenoids (lutein, 13Z-β-carotene, β-carotene, and 9Z-β-carotene) and phenolics (rosmarinic acid, ferulic acid, and sinapic acid). Contrarily, the 80 °C oven-dried flower samples contained higher levels of most amino acids and flavonoids (including acacetin and tilianin) and at 25 °C and 50 °C contained higher levels of carbohydrates. Therefore, freeze-drying is a suitable method for retaining carotenoids and phenolics. In contrast, oven drying at 50 °C was highly recommended to retain amino acids and flavonoids.

scholarly journals Evaluation of Phytochemical Content As Well As Antioxidant and Free Radical Scavenging Activity of Oven- and Freeze-Dried Hydroponic- and Soil-Grown Kale-Derived Extracts

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 369-369
Author(s):  
Alivia Setka ◽  
Rami Najjar ◽  
Maureen Meister ◽  
Rafaela Feresin
Keyword(s):  
Free Radical ◽  
Antioxidant Capacity ◽  
Freeze Drying ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
The Other ◽  
Glucosinolate Content ◽  
Oven Drying ◽  
Phytochemical Content ◽  
Freeze Dried

Abstract Objectives Hydroponic farming is a sustainable alternative to traditional soil farming. Kale is a powerhouse food rich in nutrients, polyphenols and glucosinolates. Dehydration of kale leaves for extract preparation can be done by freeze- or oven-drying. These methods can significantly affect the phytochemical content and antioxidant capacity of plant food extracts. Thus, we aimed to compare the polyphenolic and glucosinolate content and the antioxidant capacity of hydroponic- vs soil-grown and oven- vs freeze-dried kale extracts. Methods Hydroponic kale was grown in an indoor vertical hydroponic farm while soil kale was purchased from a local grocery store. Kale was then freeze- or oven-dried prior to ethanolic extraction (80%) assisted by an ultrasonic bath followed by purification with chloroform. Total polyphenol (TPC), flavonoid (TFC) and glucosinolate content (TGC) of kale extracts were determined using Folin-Ciocalteu, aluminum chloride, and palladium(II) chloride, respectively. Trolox equivalent antioxidant capacity (TEAC) and free radical scavenging power (FRAP) were used to measure antioxidant capacity and 2,2-diphenyl-1-picrylhydrazyl (DPPH) was used to measure radical scavenging capacity of kale extracts. Results Oven-dried soil-grown kale extract had significantly higher TPC and TGC than freeze-dried soil-grown as well as hydroponic-grown oven- and freeze-dried kale extracts. Soil-grown kale had higher TFC than hydroponic kale extracts; however, the TFC was not significantly different between freeze- and oven-dried kale extracts for soil- or hydroponic-grown kale extracts. Oven-dried soil-grown kale extract had the highest TEAC, which was significantly different than all the other extracts. FRAP and DPPH was significantly higher in freeze-dried soil-grown kale-derived extracts compared to all the other extracts. Conclusions Results indicate that soil-grown kale extracts had the highest TPC, TGC, and antioxidant capacity. In addition, oven-drying led to greater TFC, TGC in kale extracts than freeze-drying while freeze-drying led higher amounts of TPC compared to oven-drying. Further, freeze-dried kale extracts had higher antioxidant capacity than oven-dried. Thus, further studies are needed to examine and compare the antioxidant effects of these forms of kale extract in vivo. Funding Sources Georgia State University Honors College.

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.

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