Highest Total Soluble Solids Content Research Articles

Preparation and characterization of natamycin-incorporated agar film and its application on preservation of strawberries

This study investigated the preparation and characterization of Natamycin-incorporated agar film and its antimicrobial effect on preserve quality of fresh strawberries. Natamycin-incorporated agar films were prepared by solvent casting method and characterized in mechanical, optical, water swelling, and barrier properties. Antimicrobial activity of the films and their preservative effects on strawberries stored at 4 °C and 20 °C were also assessed. As natamycin amount increased (0%, 0.33%, 0.66%, 0.99%, 1.33%, w/w of dry film), the antimicrobial activity of the film increased with inhibition zone of Aspergillus niger and Saccharomyces cerevisiae from 0 cm to approximate 28 cm, while there was no significant effect on water vapor permeability and swelling degree. On the other hand, with the increase of natamycin, tensile strength of the film declined (from 17.61 to 14.94 MPa), while oxygen permeability enhanced from 0.161 to 0.585 × 10−15 cm3 cm/cm2 s Pa. Furthermore, the natamycin can be released quickly from antimicrobial films within 2 days under aqueous solution in accordance with fick’s law. Along with the addition of natamycin, light transmittance of antimicrobial films trends to decrease whereas the haze and total color difference of film increase significantly. Compared to control group, fungal colony number of strawberry packaged in antimicrobial film was reduced by 0.51 and 1.05 log cfu g−1 at 4 °C and 20 °C, respectively. The strawberries packaged by antimicrobial film retained high total soluble solid content with higher hardness of 61.89% and 54.47% at 4 °C and 20 °C, respectively at the end of storage. Moreover, strawberries packaged with the natamycin-incorporated film showed lower rate of water loss during storage (1.43% and 7.66% at 4 °C and 20 °C, respectively). The obtained results indicate that natamycin-incorporated agar film could be used as environment-friendly packaging alternative to preserve perishable fresh produce and extend their shelf lives by means of antimicrobial activity and other merits.

Analysis of mechanism regulating high total soluble solid content in the parthenocarpic tomato fruit induced by pat-k gene

Total soluble solid (TSS) in tomatoes is an important trait that affects consumer's preference. Previous studies have observed high TSS content in parthenocarpic tomato fruits induced by a parthenocarpic gene, pat-k. However, the mechanisms regulating high TSS content remain unknown. Hence, we have investigated the water content, metabolites involved with high TSS content, and gene expression related to starch synthesis in tomato fruits to elucidate the mechanism regulating high TSS content. We have found that independent of fruit water content, parthenocarpic fruits induced by pat-k had higher TSS content than pollinated fruits on Pat-k homozygous plants. Additionally, metabolome analysis of mature fruits has revealed that fructose influenced the difference in TSS content between pollinated fruits on Pat-k homozygous plants and the parthenocarpic fruits on pat-k homozygous plants. Furthermore, high performance liquid chromatography (HPLC) analysis showed that not only fructose contents but also glucose contents were higher in the parthenocarpic fruits on pat-k homozygous plants than pollinated fruits on Pat-k homozygous plants, suggesting that increases in these sugar contents influenced the high TSS content in the pat-k-induced parthenocarpic fruits. We also have found that parthenocarpic fruits had high starch content and upregulated Sus4, which is involved in starch synthesis, during the early stages of fruit development. Since previous reports have suggested that high starch content during the early stages of fruit development attributed to high sugar content in mature tomato fruits, our results suggest that high accumulation of starch in young fruits could be involved with high TSS content in parthenocarpic fruits induced by pat-k.

Changes of Physicochemical and Microbiological Properties of Blended Sweet and Sour Pomegranate Juices During Refrigerated Storage

Physicochemical and microbiological properties changes of new beverages combining sour (‘Garoussi 2’, ‘Mezzi 1’, ‘Mezzi 2’) and sweet (‘Gabsi’, ‘Tounsi’) pomegranate juices with different proportions (10% and 20% of sour juices) were studied over a 14 days refrigerated storage. The sour juices have proved to be very rich in total soluble solids, total anthocyanin and total phenolic contents. However, these juices are not appreciated by panellists because of high acidity content. The juice blends were characterized by an attractive red colour, acceptable acidity, higher total soluble solids content, higher total phenol and anthocyanin contents compared to sweet juices. The juice blending was found to be very effective in reducing the browning and improving the appearance of beverages during storage. High microbial loads of juice samples stored up to 14 days indicate their poor microbiological quality. The beverage based on Gabsi and Garoussi 2 (10 % and 20 % proportions) presented better nutritional and microbiological stability during storage leading to their high consumer acceptance. It was concluded that conservation of juice samples should not exceed 7 days in order to have healthy value-added beverages.

Quality testing of new Hungarian apple cultivars in normal atmosphere storage

Apples are a broadly devoured, rich wellspring of phytochemicals with many health benefits. Thus, the quality of new apple varieties should be of a high standard to please consumers. Therefore, the objective of this study was to evaluate the postharvest quality of eight apple cultivars, which were picked at different times and stored for two months before chemical component analysis. Results of the study showed significant differences among studied cultivars. Cultivar ‘Isolda’ showed a high regular fruit shape index, rich in total soluble solids content with a favorable ratio of total soluble solids content and acidity. While ‘Damra’ had a high total soluble solids content as well as pectin content. Regarding three different picking times, there was also a variation among studied apples. It can be said that these apple cultivars are suitable for fresh consumption due to their high quality. Novelty impact statement To please consumers the quality of apples should be kept high. The finding of this study revealed that new Hungarian apple cultivars showed high quality due to the high total soluble solid content, acidity, and pectin, which makes them more suitable for consumption.

Evaluation of new Turkish apricot genetic resources from the Irano-Caucasian eco-geographical group

This study presents 19 characters of 86 apricot cultivars and genotypes of the Irano- Caucasian eco-geographical group evaluated using principal component analysis. The high variability and differences among the apricot genotypes in terms of morphological, phenological and fruit quality traits were defined. The fruit size of the genotypes was generally very small (9.3 %) or small (43.0 %), the total rate of big and very big fruit genotypes was only 16.3%. The data showed that 90.1 % of the genotypes had yellow ground fruit colour, 88.4% had sweet kernel and 65% had firmness ?5 kg/cm2. About half of the apricot genotypes have 20% or high total soluble solids content. Most of the genotypes (67.3%) were harvested in mid-season and other genotypes (23.3%) were harvested early, while 4.7% of them were harvested very late, 3.5 % of the genotypes late. Only one genotype (1.2%) was harvested very early. The fruit size was highly correlated with fruit weight, pit weight and fruit flesh/pit rate. The same correlation was also observed between the fruit ground colour and fruit flesh colour. On the other hand, the total soluble solids were moderately correlated with fruit flesh firmness and seed taste. The results of the principal component analysis show that the 55% of the total variation is represented for the first three main components (22.9, 19.8, and 12.3%, respectively). The germplasm presented a large variation in the evaluated characters and most of the genotypes were found having high total soluble solids and low titratable acidity which would be beneficial for future breeding programs held to improve the related characters.

Da li primena naftenskih kiselina u ranoj fazi razvoja voća ima produženi efekat na skladišnu sposobnost i rok trajanja plodova kajsije?

In this experiment, the effects of the application of naphthenic acids (NAs) on apricots in the early fruit development phases on fruit morphological properties, composition and postharvest properties were investigated. Two concentrations of NAs (1 mg/L and 3 mg/L) were applied at two development stages in the apricot cultivar NS-4. The application of NAs at the beginning of the petal fall development phase resulted in the reduction of fruit dimensions at harvest while the application 7 days later increased fruit dimensions. Although there were no significant differences in the most investigated characteristics between fruits treated with NAs and untreated control at harvest or in the postharvest period during 20 days of cold storage (1 ± 1 °C, RD 80%) and particularly after 3 days of shelf life at room temperature. However, compared to the untreated control, apricots treated with NAs were characterized by higher total soluble solids content accompanied by higher fructose content, and lower titratable acidity accompanied by higher succinic acid content. Apricots treated with NAs showed trends towards improved sensory properties: sweeter and less sour taste, with more expressed apricot aroma accompanied with decreased gumminess and crispiness and more intensive tissue breakdown, but without expressed notes of inappropriate taste.

Da li primena naftenskih kiselina u ranoj fazi razvoja voća ima produženi efekat na skladišnu sposobnost i rok trajanja plodova kajsije?

In this experiment, the effects of the application of naphthenic acids (NAs) on apricots in the early fruit development phases on fruit morphological properties, composition and postharvest properties were investigated. Two concentrations of NAs (1 mg/L and 3 mg/L) were applied at two development stages in the apricot cultivar NS-4. The application of NAs at the beginning of the petal fall development phase resulted in the reduction of fruit dimensions at harvest while the application 7 days later increased fruit dimensions. Although there were no significant differences in the most investigated characteristics between fruits treated with NAs and untreated control at harvest or in the postharvest period during 20 days of cold storage (1 ± 1 °C, RD 80%) and particularly after 3 days of shelf life at room temperature. However, compared to the untreated control, apricots treated with NAs were characterized by higher total soluble solids content accompanied by higher fructose content, and lower titratable acidity accompanied by higher succinic acid content. Apricots treated with NAs showed trends towards improved sensory properties: sweeter and less sour taste, with more expressed apricot aroma accompanied with decreased gumminess and crispiness and more intensive tissue breakdown, but without expressed notes of inappropriate taste.

Effect of Hot Air Treatment on Physio-Chemical Properties of Pomegranate Arils

Hot air treatment has been applied on a wide range of horticultural crops to control postharvest decay and to maintain quality characteristics. To evaluate the effect of hot air treatment on physio-chemical properties of pomegranate arils, an experiment was carried out in a factorial experiment using a completely randomized design with four replications in 2015. About 200 g of ‘‘Rabab-e-Neyriz’’ pomegranate arils were placed in 350 mg polypropylene boxes with three holes on top for ventilation. Boxes were heated at 35 °C, 40 °C and 45 °C and 80% relative humidity for 30, 60, and 120 min in oven. After being cooled at an ambient temperature, boxes were stored at 5 °C (RH= 70-80%) for 15 days. The scored results of decay assay showed that heated “Rabab” arils at 35 °C till 45 °C decayed lesser than those untreated during storage period. Hot air temperature at 45 °C for 120 min resulted in the highest weight loss at the end of storage period. The highest total soluble solids content was belonged to the arils heated at 45 °C for 30 min. Hot air treatments increased pH and TSS/TA ratio of aril juice. Hot air temperature treatment decreased antioxidant activity, total phenolic compounds and total anthocyanin of arils during storage period, whilst hot air treatment had no significant effect on color values. Generally, the application of mild heat treatments could be considered as a non-contaminant postharvest tool to maintain functional and nutritive properties of arils during postharvest storage.

Effects of alkaline electrolyzed water pretreatment on the physicochemical quality attributes of fresh nectarine during storage

Chlorinated water treatment has been extensively used to manage postharvest decontamination of fruits for decades. It has been well established that chlorine may produce undesirable by-products that have a potential carcinogenic impact on human health and toxic waste on the environment. Electrolyzed water is an eco-friendly technique that has been regarded as an effective method for decontaminating microbes on fruit surfaces. However, the impact of alkaline electrolyzed water (AEW) on the physical and biochemical quality attributes of nectarine fruit during postharvest storage is not fully understood. Therefore, this study investigated the effects of AEW treatment (200 mg/L, pH, 6.7), sodium hypochlorite, and nontreated (control) on the storability, quality attribute, and decay incidence of fresh nectarine stored at −0.5℃ and 95% RH for 31 days. Results obtained indicated that the AEW treatment effectively maintains firmness, reduced weight loss, and maintains high total soluble solid content with a slight decline in titratable acidity for nectarines. Furthermore, the AEW suppresses the decrease of color qualities of the peel L*, a*, b*, reduced the incidence of browning (h°) and surface decay compared with chlorine-treated and control fruit. Novelty impact statement Alkaline electrolyzed water (AEW) and its efficacy to minimize decay and maintain physicochemical quality of nectarine fruit compared with chlorinated water treatment were investigated. Treatment with AEW (200 mg/L, 10 min) effectively preserves the freshness of the nectarine fruit by reducing surface decay compared with the chlorine-treated and control fruit. The outcome of this study provides guiding tools for stone fruit pack-houses and other industry role players on the potential of EW as an alternative to chlorine treatments.

INFLUENCE OF CULTIVAR AND FERTILIZATION WITH VERMICOMPOST ON FRUIT QUALITY AND YIELD IN LONICERA SPP.

This paper aims to study the influence of cultivar and vermicompost (organic fertilizer) treatments on fruit quality traits (fruit weight, flesh firmness, juice pH, chromatic coordinates in CIELab system, chlorophyll fluorescence) and plant productivity on Lonicera caerulea L. The experiment was carried out between 2019 and 2020, at the Research Institute for Fruit Growing Pitesti, Romania. To achieve these, three honeysuckle cultivars ('Cera', 'Loni', and 'Kami') were treated with four fertilizer doses: 0.2, 0.3, 0.75, and 1.0 L per plant. We found that 'Cera' cultivar was characterized by fruits with the highest weight (0.67 g) and firmness (13.71 units Bareiss HPE-II-FFF), 'Kami' cultivar, had the highest total soluble solids content (17.09 °Brix), and 'Loni' was the most productive (33.33 g per plant). Compared to untreated plants, fertilization with vermicompost in a dose of 0.2 L per plant increased fruit weight by 14.81%, pH by 9.79%, and fruit production per plant by 36.65%, indicating that fertilization with vermicompost could be used in ecological honeysuckle culture technology.

Identification of yeasts in different rubber leaf (Hevea brasiliensis) clones and their effects on the physical properties of fermented glutinous rice tapai

Tapai is one of the most popular traditional desserts in Malaysia and other Asian countries. Traditionally, tapai is wrapped in a rubber leaf to enhance the smell and increase its palatability. The study focused on identifying the yeasts present before and after the production of glutinous rice tapai wrapped in different rubber leaves clones, namely RRIM 2025, RRIM 2002, PB 260 and PB 350. The identification of the yeast was carried out using API 20C AUX test strips for all rubber leaves clones, glutinous rice tapai wrapped in RRIM 2025, RRIM 2002, PB 260, PB 350 and in a container (control). The results showed that Crytococcus laurentii, Rhodotorula mucilaginosa 2, Candida famata, Rhodotorula minuta were present in rubber leaf clones. While the yeasts that had been identified in tapai wrapped in rubber leaf were Candida guilliermondii, Rhodotorula mucilaginosa 2, Candida parapsilosis and Trichosporon mucoides and only C. guilliermondii was found in the container. The physical properties of the tapai that are wrapped in rubber leaves have a difference in texture, pH value and total soluble solids content compared to the control sample. The tapai sample wrapped in RRIM 2025 and RRIM 2002 had a high total soluble solid content of 45.8±0.14% and 45.78±0.16% °Bx, respectively. Meanwhile, the control sample has the highest pH value and the hardest rice kernels, which were 4.71±0.05 and 218.19±25.39 N, respectively. The results showed that the different yeasts present in the rubber leaf may cause changes in the physical properties of glutinous rice tapai.

Effect of preservation processing on quality attributes and phenolic profile of maqui (Aristotelia chilensis mol. Stuntz) fruit

Maqui is a wild native berry from the Chilean and Argentinean Patagonia that is considered an important source of bioactive compounds for its high antioxidant activity and anthocyanin concentration. Processing methods that improve shelf-life can affect stability of antioxidant compounds. Furthermore, there is limited information of the processing effect on non-anthocyanin phenolic compounds, antioxidant capacity and quality of maqui-derived products. The aim of this work was to those characteristics on processed fruit using conventional canning (CC), convective forced hot air drying (CFHAD), osmotic drying (OD), and freeze-drying (FD). Ten non-anthocyanin phenolics were quantified using HPLC-MS. Luteolin-7-O-glucoside and hydroxycinnamic acid concentration showed a significant reduction by 45% when processed using CFHAD and OD. Rutin and hyperoside concentrations were significantly higher (24.76 μg/g and 100.20 μg/g) in FD maqui when compared to CC and OD treatments. CFHAD achieved the lowest water activity (0.41) and CC the highest total soluble solids content 28.00 °Brix. Antioxidant capacity of CC maqui samples showed a 17.6% decrease, while FD, CFHAD, and OD samples showed an average 21.8% increase. The results of this work can provide valuable information to functional food producers to determine optimal processing conditions to protect antioxidant compound of maqui.

Ripening Regulation and Post-harvest Improvement of Banana Cv. Malbhog by Treating with Ethephon

A study entitled “Ripening regulation and post-harvest life improvement of banana Cv. Malbhog using ethephon” was under taken to assess the effect of ethephon on banana fruit ripening and quality parameters after harvest under ordinary room condition. The experiment was conducted at Central laboratory of Post-Harvest Horticulture of Agriculture and Forestry University, Rampur, Chitwan, Nepal in 2016. The experiment was laid out in Completely Randomized Design (CRD) in which the experiment comprised of five treatments; control(no use of ethephon), ethephon @ 250 ppm, ethephon @ 500 ppm, ethephon @ 750 ppm and ethephon @ 1000 ppm replicated four times. On the final day of storage, the maximum physiological loss in weight was observed with ethephon @ 1000 ppm (24.52 %) and the colour score (7.75). Similarly the highest Total Soluble Solids content (19.32ºBrix) was observed with ethephon @ 1000 ppm and the maximum shelf life was found with control (14 days). From the experiment, the use of ethephon @ 1000 ppm and ethephon @ 750 ppm was found more effective regarding banana ripening and other various post harvest parameters and in case, if the bananas are to be stored for long duration, the control treatement is recommended to the farmers because it increases the shelf life.

Predicting the sweetness level of avomango (Gadung Klonal 21) using multi-predictor local polynomial regression

One of the mango’s maturity aspects is the sweetness of the fruits. Mature Avomango has a high degree of sweetness, characterized by a high total soluble solids (TSS) content. Currently, many non-destructive tests are using Near Infra-Red (NIR) spectroscopy to find out the TSS content. NIR spectroscopy generates spectra data, which can be used as predictors to predict Avomangos sweetness level. This study aims to predict the level of Avomangos sweetness by using a multi-predictor local polynomial regression approach and compare it with multiple polynomial regression. In this study, we use 120 samples of Avomango divided into two parts, 100 as training data and 20 as testing data. The multi-predictor local polynomial regression has better performance with the value mean absolute percentage error (MAPE) is 8.554% that categorized as a highly accurate prediction for predicting Avomangos sweetness level.

Comparison of explosion puffing drying with other methods on the physicochemical properties and volatiles of yam (Dioscorea opposita thunb.) chips through multivariate analysis

Crisp yam chips were produced using hot air drying (AD), vacuum drying (VD), freeze drying (FD), and explosion puffing drying (EPD). As a result, the reducing sugar, total polyphenol and vitamin C contents, rehydration rate and volume ratio were well retained in freeze-dried chips with explosion puffing-dried chips following closely behind, which exhibited a higher total soluble solids content (TSS) and crispness. The microstructure of explosion puffing-dried chips showed distinct cell wall breakage and cell expansion, indicating the release of more TSSs and a relatively high hardness and crispness. Based on physicochemical chip properties, FD and EPD could be distinguished from the other drying methods, and the characteristic physicochemical properties of explosion puffing-dried yam chips were identified as the hardness and TSS level using multivariate analysis. Furthermore, 43 volatile compounds were isolated and identified in fresh yam and dried yam chips using headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). Based on the volatile compositions of the samples, oct-1-en-3-ol was identified as the major volatile compound in fresh yam, and the volatiles in the explosion puffing-dried chips were clearly distinguished from those in the other dried yam chips due to the unique puffing process.

Quality Evaluation of Strawberries Grown in Various Regions by Singaporeans and Japanese

ABSTRACT The objective of this study was to evaluate the quality of strawberries distributed in global markets. We obtained strawberries from Egypt, Mexico, the Republic of Korea, Spain, and the United States of America (US) being sold in Singapore, and compared them with Japanese strawberries (cv. Benihoppe) using instrumental analysis and sensory evaluation. Sensory evaluation was conducted by Singaporean and Japanese assessors. The results showed that the quality of strawberries in Mexico, Spain, and Egypt were relatively close, but the others were significantly different. The strawberries from the US and Japan had high total soluble solids (TSS) content, while those from Egypt, Mexico, Spain, and the US were firmer and had higher titratable acidity (TA). In the sensory evaluation, the assessors preferred strawberries with high total soluble solids (TSS) and low titratable acidity (TA). These findings suggest that varieties with high TSS and low TA are desirable for the global market. In addition, compared with the Japanese assessors, the Singaporean assessors tended to prefer strawberries with lower TA. These preferences may change depending on the eating habits of the region.

Identification and characterization of white onion (Allium cepa L.) genotypes for high total soluble solid content through molecular markers

Onion (Allium cepa L.) is one of the most important bulbous vegetable used in global kitchen. Although it has various important traits but among them the high total soluble solid content (HTSS) of white onion is highly preferred by the industries for processing purpose. Looking into the broader use of the white onion; we utilized a total of 23 polymorphic simple sequence repeats (SSRs) and intron length polymorphic markers (ILPs) to characterize thirty five white onion genotypes for HTSS. Further, we also correlated these DNA fingerprint data with the TSS for identification of HTSS and LTSS lines. The total average numbers of alleles for SSR and ILP locus, heterozygosity (He) and polymorphism information content were found to be 2.4, 0.35 and 0.29 respectively. The UPGMA dendrogram revealed two distinct clusters of genotypes. Based on the TSS and DNA genotype data, our study revealed that Bhima-shweta (LTSS-12.09%, sub-cluster IAa) & WHT-12L-HT-15-Reject-M-7(HTSS- 18.02%, cluster II) are more diverse than the others. Other white onion lines including WHTB-7G-GT-15-SC-M-7 small bulb (HTSS 18.80%), WHT-2B-GT-18-SC-M-7 (HTSS 18.51%), WHTS-4D-GT-18-MC-M-7 (HTSS 18.49%), WHTB-3C-GT-18-MC-M-7 (HTSS 18.27%) and WHTS-11K-Pickle-SC-M-7 (HTSS 17.68%) were identified as superior HTSS lines. These identified diverse HTSS and LTSS lines could be useful for the mapping of HTSS coding genes for the acceleration of molecular breeding of onion through the marker assisted selection (MAS) which could be used by the industries for the larger scale processing of the white onion products required by the global community.

Efecto de la variedad y fecha de siembra en el potencial productivo de remolacha azucarera

La remolacha azucarera es un cultivo tradicionalmente de zonas templadas, aunque el desarrollo de nuevas variedades, permite su explotación en regiones tropicales y subtropicales. Sin embargo, para obtener buenos rendimientos y alta calidad, es fundamental evaluar variedades y fechas de siembra antes de su establecimiento. El objetivo de este estudio fue evaluar el potencial productivo de tres variedades de remolacha azucarera (Coronado, Syngenta y SesVanderHaven) en dos fechas de siembra en el Campo Experimental de la Universidad de Sonora, bajo un diseño en parcelas divididas. La variedad y fecha de siembra tuvieron un efecto significativo en el diámetro de la raíz, SST y producción de follaje. La variedad Coronado sembrada en el mes de Noviembre presentó la mayor producción de raíz (109.2 t·ha-1) y mayor contenido de SST (19.3° Brix), mientras que la mayor producción de follaje (25.4 t·ha-1) en peso seco se obtuvo en el cultivar Coronado sembrado en Octubre. Los rendimientos de raíz y SST obtenidos bajo las condiciones agroecológicas del presente estudio, son similares a los mayores valores reportados en la literatura, por lo que se concluye que bajo las condiciones climáticas del presente estudio, es factible el cultivo de las tres variedades evaluadas en las dos fechas de siembras propuestas con rendimientos comparables a las explotaciones comerciales.

The Effect Of Ultraviolet Light Treatment In Extend Shelf Life And Preserve The Quality of Strawberry (Fragaria x ananassa) cv. Festival

Strawberry (Fragaria x ananassa) is a highly perishable product and rarely to be kept for more than 7 days. Cold chain system is the only methods apply in Malaysia strawberry industry to prolong the shelf life and preserve the quality of strawberry. UV light treatment proved to be effective in inhibit microbial loads and delay ripening process of fruit products where short wavelength (254 nm) ultraviolet-C was proved in keeping the freshness and quality of fruits or vegetables. This experiment was conducted to determine the effect of UV-C irradiation on extending shelf life and to determine the optimum radiation intensity of UV-C treatment on postharvest quality of treated strawberry. A total of 399 of strawberries cv. Festival were harvested in red colour with maturity stage of >80 – 85% from Cameron Highlands’s strawberry farm. The strawberries were exposed to different doses (0, 0.5, 0.6, 0.7, 0.8, 0.9 and 1.0 kJ/m2) of ultraviolet-C (254nm, UV-C) radiation. The treated strawberries were randomly placed in the polystyrene trays and stored in the dark chilling room at -5Cº for 9 days. The significant differences were found when the highest level of dosage was applied. UV-C treated strawberries with the highest doses (1.0 kJ/mº) are significantly firmer (0.557N), higher total soluble solids content (7.5 ºBrix) and ascorbic acid contain (0.518mg/ml) on day 9 (p

Processing of Herbal Tea from Roselle (Hibiscus sabdariffa L.): Effects of Drying Temperature and Brewing Conditions on Total Soluble Solid, Phenolic Content, Antioxidant Capacity and Sensory Quality

Roselle (Hibiscus sabdariffa L.) is an annual shrub popularly grown in tropical and subtropical areas. Although Roselle fruit has been used for a long time as a herbal tea due to its high content of bioactive compounds like phenolic acids and anthocyanins, the studies on the effects of the drying process and brewing conditions on the content of beneficial components and bioactivities of Roselle tea is limited. In this study, the influence of drying temperature on the retention of total phenolic content (TPC) and antioxidant capacity (AC) of the dried Roselle and the effects of brewing conditions including water temperature, liquid-solid ratio and brewing time on total soluble solid (TSS) content, total phenolic content, and antioxidant capacity of Roselle tea were investigated. The drying at 80 °C produced the dried Roselle with the highest retention of TPC (25.196 mg GAE/g) and AC (IC50 of 2.2 mg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition) and the highest sensory quality compared to the drying at other temperatures. The brewing process using hot water at 90 °C with the solid-liquid ratio of 1:10 (g/mL) for 30 min resulted in the highest TSS content (5.4 oBx), TPC (12.7 mg GAE/g dried Roselle) and AC (73.3% DPPH inhibition) of the Roselle tea. Thus, the drying at 80 °C combined with the brewing of dried Roselle for 30 min using 90 °C hot water with the solid-liquid ratio of 1:10 (g/mL) are recommended to produce Roselle tea with the highest content of beneficial ingredients.