Sun-dried Samples Research Articles

Investigation of meso- and microplastics in commercially sold dried pink shrimp in Ekiti State, South West Nigeria

Microplastics (MPs) are a global problem due to their pervasiveness and possible harm to humans and other living organisms. It has been reported that a wide variety of foods, including seafood, contain microplastics. Dried pink shrimp (Penaeus notialis) popularly called ‘dried crayfish’ is a common delicacy in many Nigerian and West African local recipes. To our knowledge, this is the first study to assess the presence of meso- and microplastics in dried shrimp in Nigeria. From a survey of five popular markets in Ekiti State, South West, Nigeria—Shasha, Oja Oba, Agric Olope, Afao (Ikere), and Oja Isale (Ifaki), 15 samples of sun- and smoke-dried pink shrimp were purchased, and their meso- (5–25 mm) and microplastic (1 to < 5 mm) content was examined. Visual inspection showed that mesoplastic particles were present in all the dried shrimp types examined. A 10% KOH solution was used to digest the samples after they had been weighed. The samples were exposed to density floatation in KI solution, followed by filtration, drying, examination under a stereomicroscope, and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrophotometer. The mean concentration of mesoplastics per 10 g of sample was 2.13 ± 0.56 for sun-dried samples and 3.20 ± 0.90 for smoke-dried samples. Microplastics had a mean concentration of 6.47 ± 1.12 in sun-dried samples and 2.87 ± 0.90 particles/10 g in smoke-dried samples. Generally, the sun-dried shrimp showed a higher prevalence of microplastics than the smoke-dried samples. The ATR-FTIR results revealed the dominance of polyethylene, PE (80%) films and fibres, followed by styrene-butadiene rubber, SBR (12%), natural latex rubber, NLR (5%), and polyvinyl alcohol, PVA (2%). Polymer hazard index (PHI) denoted that PE microplastics had a PHI score of 877.8 classifying them in the hazard category IV which is a “danger” risk. The polymers may directly enter the human body when consumed via dried shrimp and cause health implications.Graphical

Chemical composition and carbohydrates of seaweed Sargassum sp. with different drying methods

Sargassum sp., a brown seaweed abundant in Semau Island, East Nusa Tenggara, Indonesia, has potential as an alternative feed source in animal nutrition due to its rich chemical composition. This study aimed to determine Sargassum sp.'s chemical and carbohydrate composition using different drying methods to evaluate its suitability as livestock feed. A Completely Randomized Design (CRD) with three treatments—sun drying, oven drying at 60°C, and air drying—and five replications were employed. Using standard proximate analysis, fresh seaweed samples were dried according to the treatments and analyzed for dry matter, organic matter, crude protein, crude fat, crude fiber, and carbohydrate content. The results showed that the drying method significantly affected (P &lt; 0.05) the dry matter, moisture content, ash content, organic matter, crude protein, and crude fat of Sargassum sp. but had no significant effect (P &gt; 0.05) on crude fiber and carbohydrate content. Air-dried samples exhibited the highest crude protein content (6.38%) compared to sun-dried (4.71%) and oven-dried (4.94%) samples, indicating better preservation of protein at lower temperatures. Crude fat content was highest in sun-dried samples (0.56%) and lowest in air-dried samples (0.24%). Carbohydrate content ranged from 52.83% to 54.00% across all treatments without significant differences. These findings suggest that air drying is the most effective method for retaining the nutritional components of Sargassum sp., enhancing its potential as a valuable ingredient in animal feed formulations. The drying method significantly influences Sargassum sp. seaweed's chemical composition. Air drying preserves key nutritional components, making it the recommended method for processing Sargassum sp. for use in animal nutrition.

Impact of drying techniques on volatile aroma profiles and formation mechanisms of black soybean thua nao

Thua nao, a traditional Thai fermented soybean, offers a unique aroma and nutritional value. However, fresh thua nao cannot be stored for long periods due to its high in water activity (aw). This study examined the effects of various drying methods, including natural sun drying and machine drying methods, namely hot air, microwave vacuum (MIC), and vacuum drying on the qualities of dried black soybean thua nao. Our findings showed that MIC-treated sample showed the lowest aw and highest crude fat and TVB-N contents. Volatile aroma compounds were categorized according to odor description and clustered using principal component analysis (PCA). Drying methods influenced volatile compounds associated with lipid oxidation (green-fatty attribute) and the Maillard reaction (nutty-roasted, sweet, sulfurous, and smoky attributes). PCA results indicated that volatile profiles of the sun-dried sample differed from the others. This research establishes a correlation between sugar and free fatty acid precursors and aroma attributes.

Comparative Evaluation of the Proximate Composition and Amino Acid Profile in Fresh and Traditionally Sun-dried Fish Species, Puntius sophore (Hamilton, 1822) and Amblypharyngodon mola (Hamilton, 1822)

Fish is one of the most widely consumed sources of animal protein in the world. However, they are subjected to countless post-harvest changes, so technologies such as sun-drying are employed to preserve fish for a longer time. Currently, sun-dried fish also have a major place in terms of nutrients alongside fresh fish. The present study has been conducted to determine the proximate composition and amino acid content of fish species namely, Puntius sophore (Puthi), and Amblypharyngodon mola (Moa) in fresh and sun-dried conditions to enunciate the nutritional benefits of consuming sun-dried fishes together with fresh fishes. During the study period, fresh fish samples collected were divided into two batches. In one batch all the analyses were carried out under fresh conditions. In the corresponding batch, all the tests were carried out in sun-dried conditions. Proximate composition and amino acid analysis were carried out as per the guidelines of AOAC (2015). The moisture, crude protein, crude fat, ash, and carbohydrate content of the fresh and sun-dried P. sophore and A. mola revealed significantly higher moisture content in the fresh fish samples than in the sun-dried samples. Significantly higher crude protein, crude fat, ash, and carbohydrate contents were obtained in the sun-dried samples compared to the samples in fresh condition. The Essential Amino Acid (EAA) predominant in fresh and sun-dried samples of both the species were found to be Lysine and Histidine respectively. The predominant Non-essential Amino Acid (NEAA) in fresh and sun-dried samples of both species was Glutamic acid. The analysis of nutritional parameters reveals that sun-dried fish can provide comparable nutrition to fresh fish. This study is therefore designed to promote the consumption of sun-dried fish among a broader segment of society, highlighting its dietary significance.

Effect of different initial processing treatments on commercial characters and chemical components of Fritillaria taipaiensis

To investigate the effects of different initial processing methods on the quality of Fritillaria taipaiensis, this study explored the effects of anti-browning treatment, drying methods, and drying temperatures on the commercial characters, chromaticity values, and alkaloid and nucleoside components of Fritillariae Taipaiensis Bulbus. The results were comprehensively evaluated through correlation analysis(CA), principal component analysis(PCA), and hierarchical clustering analysis(HCA). Compared with those of the direct drying group(WD60), the chromaticity values(ΔE*) of the groups with scraped outer skin( FHB1) and mixed lime powder treatments(FHB2) were significantly reduced, indicating the inhibition of the browning process. The total alkaloid content of the group with mixed raw soil treatment(FHB3) and the FHB2 group showed no significant change, whereas that of the group with 5%Na Cl O solution rinse treatment(FHB4) was the lowest. Compared with air-blast dried(WD50) samples, the ΔE* values of freezedried(FS6) and vacuum-dried(FS5) samples were significantly decreased, with an increase in total alkaloid contents. Conversely,the ΔE* values of shade-dried(FS1) and sun-dried(FS2) samples were significantly increased, with severe browning and low total alkaloid contents. The total alkaloid contents of heat-pump-dried(FS4) samples showed no significant change, and their ΔE* value was significantly decreased, with a light degree of browning and favorable commercial characters. The total alkaloid content of air-blast dried samples initially increased and then decreased within the range of 40-80 ℃, and the highest content was recorded at 70 ℃. The ΔE* values of high-temperature air-blast dried samples(70-80 ℃) were smaller with a light degree of browning, whereas their texture was compact and lacked powder. CA revealed a significant relationship between the uracil content and chromaticity value of the samples(P&lt; 0. 05). The clustering relationships among samples subjected to different treatments were visualized via PCA and HCA. The results showed that FHB2 and air-blast drying(50-60 ℃) were more suitable for large-scale production, and heat pump drying could be a promising direction for future development. This study provides a scientific basis for optimizing the initial processing methods of Fritillaria taipaiensis.

QUALITY ASSESSMENT AND NUTRIENT ANALYSIS OF FREEZE-DRIED GRAPE SEED AND PEEL POWDERS

The study conducted in the year 2023 aimed to develop freeze-dried grape seed and peel powder and evaluate its quality parameters and nutrients. Sun-dried grape seed and peel powder were also developed with a significant focus on comparision with freeze-dried samples, taking into account the economic feasibility and popularity of sun drying as compared to freeze-drying. Grape seed and peel were separated manually. The seed and peel were freeze-dried and stored in a freezer and sun-dried samples were kept in airtight containers. The quality parameters, nutrient composition, and sensory characteristics of both the freeze-dried and sun-dried grape peel and seed powder were examined. Quality parameters assessed included colour, solubility, pH and sensory attributes. Nutrients analysed included ascorbic acid by dye method, iron, phosphorus and carbohydrates by colorimetry. It was observed that freeze-dried grape seed and peel powders retained more colour, while freeze-dried grape peel powder had the highest solubility (67.22%). Both freeze-dried and sun-dried grape seed and peel powder exhibited an acidic pH (3.97,5.25,4.23 and 5.06). Freeze-dried grape peel powder was found to be rich in ascorbic acid (113.49 mg). Sun-dried grape seed and freeze-dried grape peel powders were found to havehigh phosphorus content (123.33 mg) and 108.33 mg, respectively), whereas,sun-dried grape seed featured the highest iron content (25.83 mg). Freeze-dried grape seed and peel powderswere superior to sun-dried powder in quality and nutrients and hence can be used for manufacturing nutraceuticals.

Impact of Technological Processes on the Formation of Furosine, Acrylamide and Furan in Traditional Venezuelan Cocoa.

The present study was conducted to determine and analyse the content of furosine, acrylamide and furan in fermented cocoa beans from the Chuao ("criollo variety") and Barlovento ("trinitario variety") regions of Venezuela, after roasting (in the shell at 110-180 °C for 15-60 min) and alkalisation (with sodium bicarbonate or potassium carbonate, at concentrations of 10-25 g/kg in order to evaluate the impact of these operations. The highest furosine contents (up to 249 mg/100 g of protein) were found in fermented, sun-dried samples, and were higher in the nibs than in the shells. The acrylamide content increased in line with the temperature, to 160 °C in the shells, and to 180 °C in the nibs. At temperatures of up to 140 °C, the acrylamide content was higher in the shells than in the nibs. The furan content increased in line with the temperature and in this case too, was greater in the shells. The content of both furosine and furan decreased with alkalisation, while the presence of acrylamide was irregular and determined by the roasting temperature and the alkalising agent employed. Although the furosine, acrylamide and furan contents varied between the beans from the two regions and the varieties considered (Chuao and Barlovento), these three compounds were correlated to a statistically significant degree.

Isolation of Protein from Prawn Shell to Enhance Athletic Performance

Prawns, also known as shrimp, are not only a popular seafood delicacy but also a powerhouse of protein. They boast impressive nutritional profiles, making them a valuable dietary element for both general health and athletic performance. This study explores the potential of protein from white shrimp (Penaeus vannamei) as a natural supplement for athletes. The study used two drying methods: sun-drying for 48 hours and cabinet-drying at 90°C for 8 hours. Higher protein levels were found in the sun-dried samples, making them a potential candidate for superior athletic protein supplementation. Protein was subsequently isolated from this sample. Protein-fortified chocolate was developed to optimize protein consumption. The study reveals the potential of sun-dried Prawnshell (Protein) as a potent and natural muscle-building supplement, aligning with sustainable practices and athlete nutrition.

Comparison of different drying methods for bergamot peel: Chemical and physicochemical properties.

This study examines the effectiveness of seven drying methods applied to bergamot peels, encompassing hot air, microwave, infrared-assisted microwave, freeze, infrared, sun, and oven drying. All samples exhibited moisture content and water activity levels within the acceptable range for dry foods. All methods effectively transformed the peels into powdered form, yielding comparable results. Each method offers distinct advantages and disadvantages, and the choice of method should be based on the desired properties of the final product. The highest ascorbic acid content was found in freeze-dried and hot air-dried samples (>400mg/100g), whereas sun-dried samples had the lowest (89.58mg/100g). Infrared-dried samples exhibited the highest levels of total phenolics and flavonoids (193.40 and 530.14mg/100g, respectively), attributed to reactions induced by elevated temperatures. The total carotenoids were higher in freeze-dried samples (54.12mg/100g) compared to other drying methods (<27mg/100g). Microwave-dried samples had the highest 5-hydroxymethylfurfural content (73.06mg/100g), and freeze-dried samples had the highest naringin content (1568.70mg/100g). Although infrared drying had good particle density, porosity, and fluidity, freeze-drying was the most effective, retaining the highest levels of bioactive compounds. Among the methods studied, freeze-drying is recommended due to its superior ability to preserve bioactive compounds. Infrared and infrared-assisted drying methods were suitable for recovering phenolics from bergamot waste, offering lower energy consumption and practical preservation of physicochemical properties. This study emphasizes the importance of selecting the appropriate drying method to ensure high-quality dried food and producing value-added products from bergamot waste, contributing to sustainable agriculture and waste reduction. PRACTICAL APPLICATION: This study demonstrates that infrared and freeze-drying are the most effective methods for producing high-quality bergamot peel samples with enhanced antioxidant properties. These findings hold promising implications for the food industry, offering a viable approach to preserve bergamot peels and their valuable attributes.

Development and enhancement in drying performance of a novel portable greenhouse solar dryer

The increasing demand for drying technology for agriculture and food products has gained significant attention due to population explosion and inadequate resources available. The present study focuses on the concept of enhancing the drying performance of portable greenhouse solar dryer. The experimental investigations for evaluating the dryer performance were carried out while drying out onion slices. The experimentation was carried out in 4 different modes to demonstrate the effect of various modifications implemented to improve the dryer performance. The active greenhouse solar dryer (AGHSD) is the first working mode which comprises of the conventional drying system with active mode of removing moisture. The second working mode uses recirculating fans along with exhaust fans (AGHSD@circulating fans). In the third working mode an Evacuated Tube-type solar Air Heater was added to along with previous modification (AGHSD@circulating fans + ETAH). The last working mode adds an air flow distribution system to the incoming pre heated air from the Evacuated Tube-type solar Air Heater (AGHSD@circulating fans + ETAH + air flow system). Various performance characteristics like moisture ratio, heat utilization factor, coefficient of energy, heat gain and thermal efficiency of the dryer are used to analyze the changes in the drying performance. AGHSD@circulating fans + ETAH + air flow system reduced the moisture ratio in the onion slices to 5.32% from 95% in one day, compared to 19.99% for AGHSD and 46% for open sun drying. The heat utilization factor and coefficient of energy for AGHSD@circulating fans + ETAH + air flow system and AGHSD@circulating fans + ETAH improve by 10% and 15% respectively as compared to AGHSD. AGHSD@circulating fans + ETAH + air flow system shows improved heat gain of 29.53% and shows the best drying rate for the developed drying system. The thermal efficiency of AGHSD@circulating fans + ETAH + air flow system is around 60% while for AGHSD is around 41% which is higher than the thermal efficiency of 20% for sundried samples.

Drying characteristics of grain corn subjected to different drying techniques

Grain corn is one of the most important crops for feed production in Malaysia. Freshly harvested grain corn contains a significant amount of moisture content ranging from 25% to 30% (wet basis), which must be reduced to a safe level through the drying process for storage stability. In view of this, whole grain corn was subjected to various drying techniques to evaluate the drying performance and its quality retention. Grain corn was harvested at an optimum maturity of 110 days after planting and dried in ambient, sun and oven at 40°C. Ambient drying of whole grain corn showed the longest drying time, followed by sun drying and oven drying at 40°C. The time taken to reduce moisture content to less than 12% (wet basis) was observed to be 359 hrs for air-dried samples, 292 hrs for sun-dried samples and 55.5 hrs for oven-dried samples. Mathematical modelling for each drying technique demonstrated that Midili’s equation displayed the best fitting to describe the drying characteristics of air-dried samples of grain corn, while the diffusion approach’s equation was the best mathematical model for sun and oven-dried samples. The concentrations of total carotenoids in the final products for all drying treatments were in the range between 0.290 mg/g to 0.346 mg/g for all drying techniques indicating better stability with low deterioration rates when subjected to low temperature drying.

Comparative Estimation of Nutritionally Important Chemical Constituents of Red Seaweed, Gracilariopsis longissima, Affected by Different Drying Methods

In this study, the nutritional and phytochemical components of red seaweed, Gracilariopsis longissima, were assessed in relation to the effects of various drying methods (freeze, oven, and sun). Gracilariopsis longissima’s proximate composition differed significantly ( P &lt; 0.05) among the three drying techniques, with freeze-dried samples having significantly greater protein (30.63 ± 0.90% dry weight) and lipids (1.49 ± 0.05% dry weight) contents. Except for phosphorus and sulfur, the mineral concentrations were likewise considerably greater in the freeze-dried samples. The total amino acids (30.48 ± 0.06% dry weight) and fatty acids contents were substantially greater ( P &lt; 0.05) in the freeze-dried samples. In freeze-dried samples, the levels of essential amino acids (18.92 ± 0.02% dry weight) and unsaturated fatty acids (54.08 ± 0.07%) were substantially greater ( P &lt; 0.05). When compared to oven- and sun-dried samples, the total phenolic content (88.70 ± 2.19 mg GAE/g dry weight) and the flavonoid content (71.46 ± 2.17 mg QE/g dry weight) of freeze-dried samples was also substantially higher. Among the three distinct drying techniques used, the freeze-drying technique kept G. longissima’s higher nutritional and phytochemical components.

Effect of different processing methods on functional and physiochemical properties of turmeric (Curcuma longa Linn.) rhizome Var. Kapurkot Haledo-1

This study was conducted to evaluate the impact of different processing methods on the functional and phytochemical properties of turmeric rhizomes. The experiment consisted of four treatments: Treatment 1 involved oven-drying the turmeric powder, Treatment 2 involved blanching followed by oven-drying, Treatment 3 involved cooking followed by oven-drying, and Treatment 4 involved sun-drying. Each treatment was replicated four times. The major findings of the study revealed that sun-drying (68.50%) and blanching/oven-drying (66.50%) positively influenced the dispersibility of turmeric powder. Blanching/oven-drying (0.32 g/ml) and cooking/oven-drying (0.30 g/ml) significantly improved the bulk density of turmeric powder (p&lt;0.001), with no significant difference observed between these two treatments. The water absorption capacity of the turmeric powders ranged from 3.35 to 5.35 g/ml, with the sun-dried sample displaying the lowest capacity and the cooked/oven-dried sample demonstrating the highest capacity. Similarly, sun-dried powder exhibited the lowest swelling power and solubility, while heat treatment resulted in a substantial increase in both of these parameters. Additionally, the curcumin content was found to be highest in the cooked/oven-dried (3.11%) and sun-dried (2.99%) turmeric powder. In conclusion, this study suggests that blanching and cooking methods have wide applicability in the food industry to enhance the bulkiness of turmeric powder for appropriate packaging and handling. Moreover, these methods contribute to the characteristic flavor and aroma of turmeric. The findings emphasize the importance of considering different processing techniques for optimizing the functional and phytochemical properties of turmeric, thus enabling its effective utilization in various food applications.

Variations in the composition and biochemical attributes of Eucalyptus camaldulensis L. leaves essential oil as function of drying methods

The current study focuses on the chemical composition and biological properties of the hydro-distilled essential oil from Eucalyptus camaldulensis leaves, including its antibacterial, antioxidant, and anti-inflammatory properties. Three distinct drying techniques (sun drying, shade drying, and oven drying) were used to dry the plant leaves. The yield of essential oils from E. camaldulensis leaves (ELEOs) ranged from 1.0% (shade-dried sample) to 2.25% (sun-dried sample). The strongest antibacterial activity against Bacillus subtilis was seen in the essential oil from shade-dried leaves, which also had notable antioxidant and anti-inflammatory potential. The shade-dried variant, which was followed by the sun-dried and oven-dried variants, had the highest total phenolic contents (TPC), total flavonoid contents (TFC), and DPPH scavenging potential. These values were 54.07, 38.95, 16.86 (GAE mg/100g for TPC), 66.43, 29.09, 3.76 (CE mg/100g for TFC), and 66.58, 54.56, 24. 25 (IC50 μg/mL for DPPH scavenging). The shade-dried ELEOs, among others, with paw diameters of 0.739, 1.133, and 1.143 mm at 0, 30, and 60 min, respectively, showed the strongest inhibition of anti-inflammatory activity. According to GC-MS analysis, 1,8-cineole (28.08-42.70%), terpinol (11.19-19.28%), terpen-4-ol (9.74-12.33%), and β-pinene (7.89-9.51%) were the prominent components found in the evaluated ELEOs, followed by p-cymene (4.96-5.92%). The volatile profile and biological activity of ELEOs show wide variations in this study depending on the drying technique. Overall, these findings encourage peel samples to be dried at room temperature in order to gain maximal nutritional and nutraceutical benefits of this under-utilized agro-waste.

Effects of Drying Procedures on the Nutritional, Biochemical and Phytochemical Compositions of Cola nitida Seeds

The effects of drying methods on the proximate compositions and phytochemical constituents of Cola nitida seeds were investigated by exposing the kola nuts to different drying procedures. The fresh C. nitida seeds were sorted and divided into four portions with each portion subjected to air-drying (AID), solar drying (SOD), oven-drying (OVD) and sun-drying (SUD) respectively. The results obtained markedly revealed that the proximate property of C. nitida seeds varies from one drying method to the other with OVD retaining the highest moisture and fat contents but has the least ash contents. On the other hand, air-dried C. nitida samples with the maximum carbohydrate composition had the lowest fat, protein and fiber contents. The protein and ash contents of the sun-dried samples were the highest while SOD showed the least moisture and peak fiber contents respectively. Furthermore, it was observed that the phytochemical composition of C. nitida seeds on exposure to these drying procedures differs with the drying methods. Apparently, the air-dried nitida samples had the highest level of total phenols, tannins, alkaloids with good amounts of saponins. However, solar-dried C. nitida seeds which are rich in alkaloids had the least tannins, phenols and saponins composition. The trend of result from this present study revealed that the different drying methods employed in the post-harvest processing of Cola nitida seeds markedly affect the nutrient retention and bioactive constituents of kolanut.

Elite cassava clones (Manihot esculenta) grown in Zambia: effects of drying techniques on their chemical, functional, and pasting properties

IntroductionCassava (Manihot esculanta) is becoming an important crop in most developing countries, especially Zambia. However, cassava roots deteriorate quickly after harvest, producing flour or chips of sub-optimal quality. Hence the evaluation of processing procedures to extend the product's shelf-life cannot be overemphasized. This study investigated the effects of different drying methods on the chemical, functional and pasting properties of selected advanced cassava clones grown in Zambia.MethodsFresh Roots of the seven cassava clones (harvested 12 months after planting) were sampled, peeled, washed and dried using the three drying methods (sun-drying, oven-drying and freeze-drying). The flour samples from these drying methods were analyzed using standard laboratory methods for primary chemical, functional and pasting properties. The data generated were statistically analyzed for descriptive, analysis of variance (ANOVA), and the means were separated at p &amp;lt; 0.05.Results and discussionThe clone and drying method had significant effects (p &amp;lt; 0.001) on most chemical, functional and pasting properties. Clone 00/0093 had consistently lower ΔE* values for each drying method than other clones. The overall mean of total color difference (ΔE*) across the genotypes revealed the ranking ΔE* for drying techniques in the order of oven &amp;gt; sun &amp;gt; freeze drying. Generally, the highest sugar content was recorded for the freeze-dried samples. Similarly, the total starch content was higher in the sun-dried samples of six out of the seven samples than in the oven-dried samples. The functional properties ranged from 31.29–61.04%, 2.31–5.41%, 119.68–206.78% and 54–70 for solubility, swelling power, water absorption capacity and dispersibility, respectively.ConclusionIn conclusion, the clonal effect of the cassava and drying method significantly affected the cassava flours' color, chemical, functional, and pasting properties.

Effects of drying methods on nutrients and organoleptic properties of dried pawpaw chips

Fruit dehydration is one of the ways of preserving fruits and supplying consumers with healthy and nutritious fruits, particularly when these fruits are in their off-seasons. Pawpaw (Carica papaya L.) is a tropical plant grown for its edible fruit, having commercial importance because of its high nutritive and medicinal value. However, it is highly perishable. Hence, its processing and preservation are important to retain the product quality and nutritional value. This study investigated the effect of drying methods on the nutrient and organoleptic qualities of pawpaw. Fresh pawpaw fruits were purchased at Oje market in Ibadan, Nigeria. The pawpaw samples were sorted, washed with clean water, peeled and sliced into chips, then the chips were dried using five techniques - solar, open sun, oven, cabinet and dehydrator. Fresh and dried samples were evaluated for physico-chemical properties, selected bioactive compounds, colour, fibre, microbial quality and organoleptic properties. Significant (p≤0.05) differences were observed in the effects of the drying techniques employed. The pawpaw samples that were dried in the dehydrator had significantly (p≤0.05) higher amounts of bioactive compounds and TSS (8.10 ± 0.00°Bx). They also had the most appealing organoleptic properties and showed the least bacterial growth (0.14 ± 0.21 x 104cfu/g) in comparison to the samples dried using other techniques and the fresh sample (91.5 ± 13.44 x 104). While the sun-dried samples had the least fungal load (0.05 ± 0.07 x 103) in comparison to the samples dried using other techniques and the fresh sample (315 ± 7.07 x 103). Results also showed that the samples dried in the dehydrator were the lightest (26.81 ± 0.01) and yellowest (11.42 ± 0.00) of all dried samples. Generally, findings from the study showed that dried fruits portray a greater nutrient density and increased shelf life compared to fresh fruits.

Evaluation of the Quality and Antioxidant Activity of Dehydrated Medicinal Herbs

This study aims to evaluate the effects of drying in a forced-air oven or solar dryer on the drying rates, physicochemical and microbiological characteristics, and antioxidant properties of rosemary, mint, common fennel, lemon grass, and basil. The drying rates of all herbs were higher in the forced-air oven in comparison to the solar dryer. According to results obtained for herbal properties after this different drying process, mint was less affected by both drying conditions. On the other hand, regardless of the method of drying used, all dried herbs exhibited similar antioxidant properties, mainly due to the presence of total phenolics. The antioxidant activities of oven-dried herbs ranged from 19.18 to 71.55% and increased in the order common fennel &lt; lemon grass &lt; mint &lt; basil &lt; rosemary, while the activities of sun-dried samples varied from 17.73 to 58.27% and increased in the order basil &lt; common fennel &lt; lemon grass &lt; mint &lt; rosemary. The results obtained demonstrate that the process of drying can alter the quality of an herbal product, implying that standardization of post-harvest steps is essential to ensure the consistency of an herbal product.

Microbial and Fungal Contamination of Different Dried Cocoyam Flakes during Storage

Background: Contamination of food by microorganisms from the processing to the consumption stage has become a major health concern in this era, where a better approach for the elongation of food shelf life is explored. This study aims to evaluate the microbial and fungal contamination of different dried cocoyam flakes during storage.&#x0D; Methods: The cocoyam (Colocasia esculenta) samples were properly cooked, peeled, sliced into thin shapes, and dried to constant weights. The drying methods used were sun, hot-air oven, and Nigerian Stored Products Research Institute (NSPRI) multi-crop dryer; samples were divided into three groups A, B, and C, respectively, and the dried samples were stored for three months. Moisture Content (MC) was conducted using the standard method. Colonial morphology, Gram staining, and biochemical test were used to identify and characterize microorganisms. Statistical analyses were performed using SPSS 20.0.&#x0D; Results: There was a significant increase in the MC of all the samples after the storage duration. The sun-dried sample had the highest MC (13.60%) while the oven-dried sample had the lowest MC (10.82%). The sun-dried samples had the highest viable bacteria count (7.2×105 Colony Forming Unit (CFU)/g) and the oven-dried sample had the lowest count (5.1×105 CFU/g). The four bacterial isolates identified were Bacillus subtilis, Pseudomonas aeruginosa, Micrococcus luteus, and Staphylococcus aureus. The heterotrophic fungal number was the highest (0.5×103 CFU/g) regarding sun-dried samples, whereas the samples dried with NSPRI multi-crop dryer and oven-dried samples had the same value (0.3×103 CFU/g). Aspergillus flavus, A. niger, Rhizopus, Penicillium, and Mucor were isolated from the samples. Rhyzopertha dominica was identified in sun-dried samples.&#x0D; Conclusion: The increase of MC and the nature of the storage material may have contributed to high bacterial and fungal counts of stored dried cocoyam flakes, especially sun-dried ones, thereby exposing consumers to potential health risks.

Yield and Chemical Composition of Ginger Essential Oils as Affected by Inter-Varietal Variation and Drying Treatments of Rhizome

Ginger (Zingiber officinale Rosc; Zingiberaceae family) is an herb commonly used as a spice and remedy for a broad spectrum of diseases. The essential oil extracted from ginger is an effective antioxidant, anti-inflammatory, and antifungal agent. The present study has investigated the variations in yield and chemical composition of essential oils of two cultivars (Chinese and Thailand) of ginger locally available in Pakistan. Two different drying pretreatments were employed to observe the changes in compositional variations of the essential oils of ginger. The essential oil extracted from fresh, oven-dried, and sun-dried samples of two different cultivars of ginger was analyzed using gas chromatography-mass spectrometry (GC-MS). The essential oil yield was found to be highest for the sun-dried sample of each variety. The major compounds (&gt;4%) overall in the essential oil of fresh, oven-dried, and sun-dried ginger samples from Thailand origin were camphene, 3-carene, o-cymene, caryophyllene, α-curcumene, sabinol trans, citral, and santalol. Major compounds overall in the essential oil of fresh, oven-dried, and sun-dried ginger samples of Chinese origin were α-pinene, Camphene, limonene, longicyclene, copaene, longifolene, β-sesquiphellandrene, alloaromadendrene, γ-muurolene, α-curcumene, α-farnesene, and citral. The inter-varietal variations and pretreatment methods considerably affected yield and chemical composition. Cluster analysis was performed to validate the results further. Significantly varying compounds responsible for the significant variation among varieties and treatments of the ginger were identifies by using the heat map. There was clear differentiation among Chinese and Thailand varieties due to the variation in the concentrations of the volatile compounds. The results obtained can be helpful for the ginger growers and end users to choose the ginger variety and the way of use that is more beneficial.