Effect of drying methods (microwave vacuum, freeze, hot air and sun drying) on physical, chemical and nutritional attributes of five pepper (Capsicum annuum var. annuum
) cultivars

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).

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Impact of Different Drying Techniques on Quality Traits of Ginger (Zingiber officinale Rosc.) Rhizomes

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2021/v11i1230553 ◽

2021 ◽

pp. 30-37

Author(s):

Annu Kumari ◽

Yeluru Mohan Babu ◽

Eggadi Ramesh ◽

Tshering Ongchu Lepcha ◽

Suman Tamang ◽

...

Keyword(s):

Essential Oil ◽

Fiber Content ◽

Microwave Drying ◽

Crude Fiber ◽

Drying Methods ◽

Hot Air Drying ◽

Air Drying ◽

Sun Drying ◽

Crude Fiber Content ◽

Hot Air

Under the present investigation, ginger was produced at the instruction cum research plots of the Department of Plantation Crops and Processing, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal. The experiment was laid out in a factorial CRD. The study was undertaken with four ginger varieties namely Gorubathan, Suprabha, Suruchi and Suravi to evaluate the effect of different drying methods (sun drying, hot air drying at 50OC, 60oC and 70oC and microwave drying on time required for drying to a moisture content of 8 – 10% and to chemical composition (essential oil, oleoresin content and crude fiber content) of the end product. Results shown that Gorubathan variety has the highest essential oil (2.243%) and oleoresin content (14.840%) among the four varieties in this study, highest crude fiber content (5.253%) was observed in Suprabha and highest dry recovery (25.77%) was obtained from Suravi variety. In hot air drying, with increase in temperature essential oil, oleoresin and crude fiber content in dry ginger as well as dry recovery reduced. With high dry recovery (25.77%), essential oil (2.037%) and oleoresin content (13.510%) and moderately low crude fiber content (4.637%), it can be concluded that Suravi variety is best suitable for producing dry ginger. Apart from microwave drying, sun drying can be recommended as better practice, when hygienically conducted, based on essential oil and oleoresin content.

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Evaluation of the functional properties of bael powder using different drying methods

FOOD SCIENCE RESEARCH JOURNAL ◽

10.15740/has/fsrj/11.2/47-55 ◽

2020 ◽

Vol 11 (2) ◽

pp. 47-55

Author(s):

Vipul Chaudhary ◽

Vivak Kumar ◽

B.R. Singh ◽

Jaivir Singh ◽

Neelash Chauhan ◽

...

Keyword(s):

Functional Properties ◽

Value Added ◽

Absorption Capacity ◽

Drying Methods ◽

Sun Drying ◽

Hot Air ◽

Swelling Capacity ◽

Tray Drying ◽

Bael Powder

The study were carried out to evaluate the effect of different varieties of bael (Pant Aparna, Pant Shivani and Pant Urvashi) dried by different method such as open sun drying, tray drying (600C and 700C) and hot air oven drying (600C and 700C) on functional properties of bael powder. The functional properties such as swelling capacity, water absorption capacity, oil absorption capacity, foam capacity, solubility and bulk density were decreased with increase in drying temperature. The result showed that the Variety Pant Aparna at 600C cabinet tray drying and Variety Pant Aparna by open sun drying bael powder had highest functional properties compared to others treated bael powder. Bael powder has good functional properties which enhance the nutritional quality of the value added products.

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Composition Changes in Lycium ruthenicum Fruit Dried by Different Methods

Frontiers in Nutrition ◽

10.3389/fnut.2021.737521 ◽

2021 ◽

Vol 8 ◽

Author(s):

Youyuan Lu ◽

Xiangfeng Kong ◽

Juanhong Zhang ◽

Chao Guo ◽

Zhuo Qu ◽

...

Keyword(s):

Antioxidant Activity ◽

Moisture Content ◽

Shelf Life ◽

Total Phenolic ◽

Drying Methods ◽

Hot Air Drying ◽

Air Drying ◽

Sun Drying ◽

Hot Air ◽

Lycium Ruthenicum

The fruit of Lycium ruthenicum (LRF), known as black wolfberry, is a medicinal and edible fruit. The fresh LRF is perishable and has only about 3 days of shelf life. Drying could prolong the shelf life of LRF. However, it could imply physical changes and chemical modification. This study evaluated the effect of sun drying (SD), hot air drying (HD), and freeze drying (FD) on the appearance characteristics, moisture content, bioactive compounds, amino acid composition, and antioxidant activity of LRF. The results showed that LRF dried by FD was round, expansive, fragile, and maintained the largest amount of appearance traits among the three drying methods. Drying methods had a significant effect on phytochemical content and antioxidant activity of LRF (P < 0.05). Principal component analysis (PCA) showed that procyanidin content (PAC), asparagine (Asn), total phenolic content (TPC), total anthocyanin content (TAC), and moisture content were the main sources of the difference in LRF dried by different methods. The characteristic of LRF in FD was low moisture content, and high TPC, Asn, PAC, and TAC. Sun drying was opposite to FD. Hot air drying was high TPC and low TAC content. The quality of LRF was in the order of FD > HD > SD based on comprehensive evaluation of the phytochemical component content and antioxidant capacity. Additionally, the water temperature and soaking time had different antioxidant activity effect on LRF dried by different methods. These findings will provide useful information for production and utilization of LRF.

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Impact of different drying methods on sensory properties of osmotic dehydrated pineapple slices

Asian Journal of Dairy and Food Research ◽

10.18805/ajdfr.dr-1434 ◽

2019 ◽

Author(s):

Vipul Chaudhary ◽

Vivak Kumar ◽

Sunil . ◽

Balwant Singh ◽

Ratnesh Kumar ◽

...

Keyword(s):

Experimental Study ◽

Sensory Evaluation ◽

Agricultural Products ◽

Drying Methods ◽

Sun Drying ◽

Overall Acceptability ◽

Hot Air ◽

Drying System ◽

Osmotic Treatment ◽

The Right

Drying is an essential process in the preservation of agricultural products. Various drying methods are employed to dry different agricultural products. Each method has its own advantages and limitations. Choosing the right drying system is thus important in the process of drying agricultural products. Drying reduces the possibilities of the contamination by insects and microorganisms so that product is prevented. An experimental study was performed to determine the Sensory Evaluation of pineapple slices subjected to drying in open sun drying, cabinet tray dryer at 50oC, 60oC and 70oC and hot air oven at 50oC, 60oC and 70oC with osmotic treatment indicated that T0 (Control), T1(50oBrix) and T2 (60oBrix). The result obtained showed that a product osmo- treated 60obrix at 50oC tray dried shows the better texture, flavor, color, taste and overall acceptability.

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Effects of Cooking and Processing Methods on Phenolic Contents and Antioxidant and Anti-Proliferative Activities of Broccoli Florets

Antioxidants ◽

10.3390/antiox10050641 ◽

2021 ◽

Vol 10 (5) ◽

pp. 641

Author(s):

Hee Young Kim ◽

Meran Keshawa Ediriweera ◽

Kyung-Hwan Boo ◽

Chang Sook Kim ◽

Somi Kim Cho

Keyword(s):

Antioxidant Activity ◽

High Performance ◽

Radical Scavenging ◽

Steam Treatment ◽

Drying Methods ◽

Processing Methods ◽

Phenolic Contents ◽

Hot Air ◽

Freeze Dried ◽

Mcf 7

We investigated the effects of cooking (steaming and microwaving) and processing (freeze-drying and hot-air-drying) methods on the antioxidant activity of broccoli florets. 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•), and alkyl• free radical scavenging assays were employed to assess anti-oxidant potentials. The cytoprotective effect against oxidative damage induced by H2O2 was studied using hepatocellular carcinoma (HepG2) cells. Anti-proliferative effects were assessed in MCF-7 and MDA-MB-231 breast cancer cells. L-sulforaphane in broccoli extracts was quantified using high-performance liquid chromatography (HPLC). Steam and microwave treatments caused increases in total polyphenol content (TPC), whereas the total flavonoid content (TFC) decreased following steam treatment. A slight increase in TFC was observed in the microwaved samples. Extracts of all broccoli samples showed almost identical radical scavenging and cytoprotective effects. HPLC demonstrated that steamed (3 min)-freeze-dried (F-S3) and microwaved (2 min)-freeze-dried (F-M2) samples exhibited elevated levels of L-sulforaphane. In addition, the F-S3 and F-M2 extracts displayed strong anti-proliferative effects in MCF-7 cells, which correlated with L-sulforaphane content. As we observed no significant decrease in the antioxidant activity of broccoli florets, the cooking and processing methods and conditions studied here are recommended for broccoli.

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Supercritical CO2 Extraction of Phytocompounds from Olive Pomace Subjected to Different Drying Methods

Molecules ◽

10.3390/molecules26030598 ◽

2021 ◽

Vol 26 (3) ◽

pp. 598

Author(s):

Graziana Difonzo ◽

Antonella Aresta ◽

Pietro Cotugno ◽

Roberta Ragni ◽

Giacomo Squeo ◽

...

Keyword(s):

Olive Oil ◽

Freeze Drying ◽

Oil Production ◽

Production Costs ◽

Drying Methods ◽

Olive Pomace ◽

Hot Air Drying ◽

Air Drying ◽

Hot Air ◽

Pharmaceutical Industries

Olive pomace is a semisolid by-product of olive oil production and represents a valuable source of functional phytocompounds. The valorization of agro-food chain by-products represents a key factor in reducing production costs, providing benefits related to their reuse. On this ground, we herein investigate extraction methods with supercritical carbon dioxide (SC-CO2) of functional phytocompounds from olive pomace samples subjected to two different drying methods, i.e., freeze drying and hot-air drying. Olive pomace was produced using the two most common industrial olive oil production processes, one based on the two-phase (2P) decanter and one based on the three-phase (3P) decanter. Our results show that freeze drying more efficiently preserves phytocompounds such as α-tocopherol, carotenoids, chlorophylls, and polyphenols, whereas hot-air drying does not compromise the β-sitosterol content and the extraction of squalene is not dependent on the drying method used. Moreover, higher amounts of α-tocopherol and polyphenols were extracted from 2P olive pomace, while β-sitosterol, chlorophylls, and carotenoids were more concentrated in 3P olive pomace. Finally, tocopherol and pigment/polyphenol fractions exerted antioxidant activity in vitro and in accelerated oxidative conditions. These results highlight the potential of olive pomace to be upcycled by extracting from it, with green methods, functional phytocompounds for reuse in food and pharmaceutical industries.

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Effects of Blanching and Natural Convection Solar Drying on Quality Characteristics of Red Pepper (Capsicum annuum L.)

International Journal of Food Science ◽

10.1155/2017/4656814 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

James Owusu-Kwarteng ◽

Francis K. K. Kori ◽

Fortune Akabanda

Keyword(s):

Natural Convection ◽

Quality Characteristics ◽

Red Pepper ◽

Plain Water ◽

Drying Methods ◽

Solar Drying ◽

Drying Time ◽

Sun Drying ◽

Overall Acceptability ◽

Solar Dryer

The objective of this work was to determine the effects of blanching and two drying methods, open-sun drying and natural convection solar drying, on the quality characteristics of red pepper. A 2 × 3 factorial design with experimental factors as 2 drying methods (open-sun drying and use of solar dryer) and 3 levels of pepper blanching (unblanched, blanched in plain water, and blanched in 2% NaCl) was conducted. Dried pepper samples were analysed for chemical composition, microbial load, and consumer sensory acceptability. Blanching of pepper in 2% NaCl solution followed by drying in a natural convection solar dryer reduced drying time by 15 hours. Similarly, a combination of blanching and drying in the solar dryer improved microbial quality of dried pepper. However, blanching and drying processes resulted in reduction in nutrients such as vitamin C and minerals content of pepper. Blanching followed by drying in natural convection solar dryer had the highest consumer acceptability scores for colour and overall acceptability, while texture and aroma were not significantly (p>0.05) affected by the different treatments. Therefore, natural convection solar dryer can be used to dry pepper with acceptable microbial and sensory qualities, as an alternative to open-sun drying.

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Comparative Study of Hot Air Drying and Microwave Drying for Dewatered Sludge

10.21203/rs.3.rs-178542/v1 ◽

2021 ◽

Author(s):

Wittawat Wulyapash ◽

Awassada Phongphiphat ◽

Sirintornthep Towprayoon

Keyword(s):

Microwave Power ◽

Specific Energy Consumption ◽

Microwave Drying ◽

Drying Methods ◽

Drying Time ◽

Hot Air ◽

Air Temperatures ◽

Dewatered Sludge ◽

Dried Sludge ◽

Seafood Processing

Abstract Large amounts of sludge are generated from wastewater treatment in seafood processing industries. Most of the dewatered sludge in Thailand is not utilized and disposed by landfilling. The dried sludge utilization as refuse-derived fuel (RDF) is an alternative solution due to the gross calorific value (GCV), which is greater than 21.9 MJ/kg. However, the key obstacle is its high moisture content of 87.4% (wet basis). Therefore, drying methods using hot air and microwave techniques were investigated for preparing dried sludge. The effects of hot air temperatures (100-150 °C) and microwave power levels (100-800 W) were compared on drying kinetics, specific energy consumption (SEC), and characteristics of the dried products. The results showed that drying times were decreased by increasing the hot air temperatures. In the same way, the increase in microwave power levels decreased the drying time. The application of microwaves contributed to reducing the drying time by more than 46% compared to the hot air. The reduction of drying times resulted in the saving SEC. The GCV of the dried sludge decreased with the decrease in the volatile matter (VM) due to the high component of VM as 79.5-80.3% (dry ash-free basis). The sludge dried by the microwaves showed a lower GCV than the hot air products. However, dried sludges still had high GCV (≥ 20.8 MJ/kg). Furthermore, the minimal variation of the product characteristics demonstrated that the microwave technique could be applied as an alternative drying method with a rapid process compared to the conventional hot air technique.

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Physicochemical Characteristics of Sun-dried and Roasted Cassava Rice

Jurnal Agritech ◽

10.22146/agritech.37657 ◽

2019 ◽

Vol 39 (4) ◽

pp. 338

Author(s):

Rudiati Evi Masithoh ◽

Maynanda Brigita Chrysta ◽

Sabila Avinda Deviana

Keyword(s):

Chemical Properties ◽

Physicochemical Characteristics ◽

Paddy Rice ◽

Drying Methods ◽

High Demand ◽

Mineral Contents ◽

Carbohydrate Source ◽

Nutritional Values ◽

Physical Chemical ◽

And Chemical Properties

High demand of rice can be minimized by promoting cassava as an alternative carbohydrate source. One method to process cassava to ease consumption and to prolong its shelf-life is by making it into analog rice, namely cassava rice. Two drying methods were studied to obtain the physicochemical information of cassava rice. This research aimed at determining color and chemical properties, i.e. water content, ash, lipid, protein, carbohydrate, starch, amylose, amylopectin, and mineral contents of cassava rice processed by roasting and sun-drying. It also compared physicochemical characteristics of cassava rice and paddy rice to get better understanding of nutritional values of cassava rice. Results showed that physical, chemical, and mineral contents of cassava rice were different from paddy rice. Cassava rice had lower water, protein, Zn and P2O5 contents than paddy rice. Roasted cassava rice was darker than cassava rice. Sun-dried and roasted cassava rice showed no different values in terms of lipid, carbohydrate, starch, amylose, amylopectin, Mg, Zn and P2O5 contents, while other characteristics were similar.

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