scholarly journals Spectra evolution over on-vine holding of Italia table grapes: prediction of maturity and discrimination for harvest times using a Vis-NIR hyperspectral device

2017 ◽  
Vol 48 (2) ◽  
pp. 109 ◽  
Author(s):  
Francesca Piazzolla ◽  
Maria Luisa Amodio ◽  
Giancarlo Colelli
Keyword(s):  
Antioxidant Activity ◽  
Near Infrared ◽  
Prediction Models ◽  
Ph Value ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Harvest Time ◽  
Table Grapes ◽  
Grape Quality

Measurement of certain grape quality parameters (sugars, acidity, and pH-value) is essential for the determination of the optimum harvest time. Non-destructive analytical techniques, including near infrared (NIR) spectroscopy, can be valid alternatives to traditional analytical methods for the determination of maturity indexes, enabling the possibility of on-field applications. This work aims to study the reliability to monitor spectra changes related with ripening of table grapes and to select optimal wavelengths for the discrimination of bunches from different harvests, in addition to the prediction of total soluble solids, pH, titratable acidity, phenols and antioxidant activity of table grapes. Grapes were harvested four times from the same plants at day 0 (I HT), and after 11 (II HT), 27 (III HT) and 48 (IV HT) days. Spectra were acquired from the images obtained using a spectral scanner Vis-NIR (ver 1.4.; DV Srl, Padova, Italy), with a detector in the region between 400-1000 nm principal component analysis was used to remove outliers followed by spectra pre-treatment. The best prediction model was achieved for soluble solids with the regression coefficient values of 0.91 for calibration and 0.88 for validation followed by titratable acidity (0.71 and 0.78) and antioxidant activity (0.68 and 0.62). In addition an excellent correlation was observed between spectra and days before harvest (R2 of 0.98 for calibration and prediction models) indicating that is possible to relate spectra changes with ripening, leading also to the effective discrimination of the fruits from the different harvest times. The results showed that this technique may be a valid support to select the optimal harvest time also based on the prediction of the maturity related constituents.

scholarly journals Non-invasive Monitoring of Berry Ripening Using On-the-Go Hyperspectral Imaging in the Vineyard

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2534
Author(s):  
Juan Fernández-Novales ◽  
Ignacio Barrio ◽  
María Paz Diago
Keyword(s):  
Hyperspectral Imaging ◽  
Malic Acid ◽  
Prediction Models ◽  
External Validation ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Total Polyphenols ◽  
Grape Quality ◽  
Entire Experiment ◽  
La Rioja

Hyperspectral imaging offers enormous potential for measuring grape composition with a high degree of representativity, allowing all exposed grapes from the cluster to be examined non-destructively. On-the-go hyperspectral images were acquired using a push broom hyperspectral camera (400–100 nm) that was mounted in the front part of a motorized platform moving at 5 km/h in a commercial Tempranillo vineyard in La Rioja, Spain. Measurements were collected on three dates during grape ripening in 2018 on the east side of the canopy, which was defoliated in the basal fruiting zone. A total of 144 grape clusters were measured for Total soluble solids (TSS), Titratable acidity (TA), pH, Tartaric and Malic acid, Anthocyanins and Total polyphenols, using standard wet chemistry reference methods, throughout the entire experiment. Partial Least Squares (PLS) regression was used to build calibration, cross validation and prediction models for the grape composition parameters. The best performances returned determination coefficients values of external validation (R2p) of 0.82 for TSS, 0.81 for Titratable acidity, 0.61 for pH, 0.62 for Tartaric acid, 0.84 for Malic acid, 0.88 for Anthocyanins and 0.55 for Total polyphenols. The promising results exposed in this work disclosed a notable methodology on-the-go for the non-destructive, in-field assessment of grape quality composition parameters along the ripening period.

scholarly journals The overall precision test for near infrared scanning and reference method for the determination of soluble solids content and pH of mango for processing factory

2020 ◽  
Vol 187 ◽  
pp. 04003
Author(s):  
Nphatsanan Saksangium ◽  
Panmanas Sirisomboon
Keyword(s):  
Near Infrared ◽  
Prediction Models ◽  
Reference Method ◽  
Nir Spectroscopy ◽  
Soluble Solids ◽  
Reference Test ◽  
Infrared Scanning ◽  
Solids Content ◽  
Precision Test

Near infrared (NIR) spectroscopy is a rapid technique for nondestructive testing. Mango is popular fruit in Thailand. Therefore, The main aim of this paper is to report an overall precision of the NIR spectroscopy instruments and reference methods for determination at the beginning of the experiment for prediction models development to be in the mango applied processing factory.. Results showed that the repeatability of FT-NIR spectrometer and UV-VIS-NIR spectrometer were 0.00191 and 0.00529, respectively. The reproducibility of FT-NIR spectrometer and UV-VIS-NIR spectrometer were 0.00323 and 0.03561, respectively. Repeatability of reference test of TSS and pH were 0.1657 and 0.0827. Therefore, the R2max of TSS and pH were 0.9825 and 0.9504 which indicates that it is possible to develop NIR model for prediction of total soluble solids and pH.

scholarly journals Determination of the harvest time of sugar apples (Annona squamosa L.) in function of carpel interspace

2020 ◽  
Vol 43 ◽  
pp. e48732
Author(s):  
Elias Ariel Moura ◽  
Pollyana Cardoso Chagas ◽  
Railin Rodrigues Oliveira ◽  
Daniel Lucas Lima Taveira ◽  
Maria Luiza Grigio ◽  
...  
Keyword(s):  
Titratable Acidity ◽  
Soluble Solids ◽  
Pulp Yield ◽  
Harvest Time ◽  
Fruit Peel ◽  
Hue Angle ◽  
Postharvest Life ◽  
Stage 1 ◽  
Apple Fruits

Sugar apples have attracted attention in recent years due to their medicinal and nutritional properties. However, the shelf life of sugar apples is one of the most concerning problems owing to their perishability. This work aimed to determine the ideal harvest time for sugar apple fruits in relation to different classes of carpel interspaces. Therefore, fruits were classified into three stages according to the carpel interspace: stage 1 (0.0 - 2.0 mm); stage 2 (2.1 - 3.0 mm); and stage 3 (3.0 - 4.0 mm). After harvesting, the fruits were evaluated daily in the laboratory regarding their physical and physicochemical aspects until they reached the point of consumption (horticultural maturation). The following variables were evaluated: fruit diameter and length (mm); fruit, peel, pulp, and seed masses (g); color index, including the chromatic attributes L* (luminosity), C* (chroma), and h* (hue angle); bark firmness (N); soluble solids (°Brix); titratable acidity (g citric acid 100 g-1 of pulp-1); pulp yield; and ratio SS/TA. Fruits at stage 3 showed larger diameters, less firmness, and better chromaticity means. Fruits at stages 2 and 3 had eight days of postharvest life. However, fruits at stage 2 took longer for 50% of the fruits to be ready for consumption. The results demonstrate that stages 2 and 3 can be determinants for the harvest time of sugar apples.

Study of the quality and antioxidant properties of tomatoes (Solanum lycopersicum L.) under different postharvest and dehydration conditions

2020 ◽  
Vol 13 (9) ◽  
Author(s):  
María Lorena Luna-Guevara ◽  
Teresita González-Sánchez ◽  
Adriana Delgado-Alvarado ◽  
María Elena Ramos-Cassellis ◽  
José Guillermo Pérez-Luna ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Rural Communities ◽  
Antioxidant Properties ◽  
Titratable Acidity ◽  
Physicochemical Characteristics ◽  
Soluble Solids ◽  
Convective Drying ◽  
Tomato Fruits ◽  
Solanum Lycopersicum L ◽  
Storage Temperatures

Objective: To study the effect of storage temperatures and dehydration conditions (solar and convective drying; SD, CD), on the quality, physicochemical parameters and antioxidant properties of tomato fruits. Methodology: The physicochemical characteristics pH, titratable acidity, soluble solids (°Bx) and color parameters (L*, a* and b*), were evaluated. The lycopene, carotenoids and antioxidant activity percentages retention of tomatoes fruits stored at 7 and 22 ° C for 5 days and subjected to SD (Temperature (T) of 67 °C and luminescence of 685 lum/sqf) and CD (T 70 °C, flow rates 0.5, 1.0 and 1.5 m/s), were analyzed. Results: The fruits reached humidities of 17 and 15% for SD and CD. The parameters pH, °Bx, L*, a*, b* were highest with 22°C and CD (1.5 m/s). The value of the carotenoids was higher in fruits stored at 7 ° C and subjected to CD (1.0 and 1.5 m/s) and SD with values of 83.85, 85.98 and 99.43%, respectively. The CD (0.5 m/s) and SD improved lycopene (94.37 and 95.14%) and the antioxidant activity with values of 73.06 and 97.21%. Implications: The application of solar dehydration depends on luminescence condition; however, it is inexpensive and environmentally friendly alternative. Conclusions: The results derived in a viable alternative for the conservation and commercialization of tomato fruits in rural communities

scholarly journals Physicochemical Characterization and Functional Potential of Phaseolus vulgaris L. and Phaseolus coccineus L. Landrace Green Beans

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 803
Author(s):  
Elia Nora Aquino-Bolaños ◽  
Alma Karina Garzón-García ◽  
Jimena Esther Alba-Jiménez ◽  
José Luis Chávez-Servia ◽  
Araceli Minerva Vera-Guzmán ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Physicochemical Characterization ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Green Beans ◽  
Total Sugars ◽  
Total Soluble Solids ◽  
Color Parameters

The green bean is an important crop worldwide, because it is rich in protein, dietary fiber, vitamins, and minerals, as well as bioactive compounds that provide it with important functional properties; however, the composition of many landraces is still unknown. The purpose of this project was to characterize Phaselus vulgaris and coccineus L. landrace green beans on pH, titratable acidity, total soluble solids, total sugars, color parameters, total phenols, monomeric anthocyanins, and in vitro antioxidant activity (DPPH and FRAP). Regarding the content of total sugars, differences were registered between both species, as opposed to results observed in total soluble solids. Color parameters showed higher reddish tones for P. vulgaris landraces, though P. coccineus had a higher total phenolic content, especially the reddish landraces, which correlated directly to a higher antioxidant activity by DPPH and FRAP. In the protein content, the species P. vulgaris registered the highest content. These results could contribute to a greater use and even promote the genetic improvement of the outstanding pods that serve as one of the main food products in rural regions for higher benefits.

scholarly journals Determination of titratable acidity in white wine

2007 ◽  
Vol 52 (2) ◽  
pp. 169-184 ◽  
Author(s):  
Milos Rajkovic ◽  
Ivana Novakovic ◽  
Aleksandar Petrovic
Keyword(s):  
Tartaric Acid ◽  
Potentiometric Titration ◽  
Ph Value ◽  
Titratable Acidity ◽  
White Wine ◽  
Selective Electrode ◽  
Alcohol Fermentation ◽  
Standard Methods ◽  
Illegal Acts

The amount of titration acid in must is in the largest number of cases with in the range 5.0-8.0 g/dm3. Wines, as a rule, contain less acids than must, and according to Regulations, titratable acidity is in the range of 4.0-8.0 g/dm3 expressed in tartaric acid, because a part of tartaric acid is deposited in the form of salts (tartar or argol) during alcohol fermentation. For wines that contain less than 4 g/dm3 of titratable acids there arises a suspicion about their origin, that is, that during the preparation some illegal acts were done. Because of that, the aim of this paper is to determine titratable acidity in white wine, using standard methods of determination, which are compared with the results received by potentiometric titration using ion-selective electrode. According to the received results it can be seen that wine titration with indicator gives sufficient reliable values of wine titration acidity. However, as potentiometric titration at pH value 7.00 is more reliable and objective method, the values of titratable acids content in wine, expressed through tartaric acid, are given according to this result. The analysis of differential potentiometric curves shows that these curves can give us an answer to the question of the presence of a larger amount of other nonorganic substances, which have already existed in wine. However, none of the used methods gives absolutely reliable answer what substances are present in analysed samples.

scholarly journals Evaluation of fermented tea (kombucha) quality

2020 ◽  
Vol 26 (4) ◽  
Author(s):  
Vanesa Šliažaitė ◽  
Aurelija Paulauskienė ◽  
Aurimas Krasauskas
Keyword(s):  
Antioxidant Activity ◽  
Acetic Acid ◽  
Sensory Evaluation ◽  
Total Content ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Soluble Solids Content ◽  
Fermentation Conditions ◽  
Solids Content

The research was done at Aleksandras Stulginskis University (Vytautas Magnus University Agriculture Academy since 2019) in 2017–2018. The research object was kombucha beverage brewed from Camellia sinensis L. black, green, oolong, pu-erh tea and fermented for 9 and 22 days by microorganisms at different room lighting conditions. The soluble solids content, active acidity and titratable acidity were determined in teas fermented for 22 days. The total amount of phenolics compounds, antioxidant activity, yeast colonies and sensory evaluation of tea were determined in teas fermented for 9 days. The research results showed that the quality of fermented tea was dependent on the tea species, but fermentation conditions were not essential. During the fermentation the soluble solids content of tea decreased by an average of 0.60% and the content of acetic acid increased by 0.34%. The highest content of acetic acid was found on the 22nd day of fermentation in all species of teas. The active acidity (pH) of all investigated species of teas decreased significantly during the fermentation process. The total content of phenolic compunds in all species of teas during the fermentation increased from 20 to 57% regardless of fermentation conditions. The highest content of total phenolic compounds was established in teas fermented for 9 days. The antioxidant activity of teas fermented for 9 days varied depending on the fermentation conditions. For black and green teas fermented in the light the antioxidant activity decreased, for oolong and pu-erh teas fermented in the dark the antioxidant activity increased. The number of yeast colonies increased in all tea samples during the fermentation. The best taste was fixed for pu-erh tea, which scored the highest (11.4) in sensory evaluation.

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