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•NIR spectroscopy was applied for monitoring fermentation process of mulberry vinegar.•The calibration performances of two kinds of NIR spectrometers were compared.•The total acids ...and total polyphenol content can be determined by NIR spectroscopy.•A low-cost MEMS NIR spectrometer can obtain a good prediction performance.
This study evaluated the potential of Micro-Electro-Mechanical System (MEMS) and optical fiber Near-Infrared (NIR) spectrometers as a rapid method for monitoring total acids (TA) and total polyphenol content (TPC) in the fermentation process of mulberry vinegar. The NIR spectrometers Digital Light Processing (DLP) NIRscan Nano EVM (MEMS instrument) were used for this purpose, and another NIR spectrometer NIRQuest 512 was used for comparison. The standard Normal Variate (SNV) was selected as the best method used to pre-process spectra, and the competitive adaptive reweighted sampling (CARS) was applied to optimize wavelength variables, which were then subjected to partial least squares (PLS) regression. The results showed that TA and TPC could be determined. For TA, NIRQuest 512 provided a good predictive performance with the root-mean-square error of prediction set (RMSEP) of 0.22% and the R-squared of prediction set (R2P) of 0.977, whiles DLP NIRscan Nano EVM obtained the RMSEP of 0.32% and R2p of 0.950. For TPC, the NIRQuest 512 provided a predictive performance with the RMSEP of 8.11 mgGAE/L (mg gallic acid equivalent/L) and R2P of 0.820, and DLP NIRscan Nano EVM had the RMSEP of 8.22 mg GAE/L and R2p of 0.800. In conclusion, the low-price MEMS NIR instruments DLP NIRscan Nano EVM can be applied to monitor TA and TPC in the fermentation broth of mulberry vinegar.
•A colorimetric sensor array was constructed based on indicator displacement assay.•The mechanism of indicator replacement assay was verified by UV.•Total acids in apple vinegar fermentation were ...rapidly monitored by a sensor array.•SVR model achieved a better prediction performance for total acids content.
In this work, a colorimetric sensor array (CSA) for quantitative determination of total acids in apple vinegar during fermentation was constructed. The sensor array was properly designed based on indicators displacement assay (IDA) using three metal ions (Cu2+, Zn2+ and Ni2+) as receptors to organic acids. The time stability results showed that the prepared CSA had good operational stability. Three quantitative models, including one linear (partial least square, PLS) and two nonlinear (support vector regression, SVR and back propagation artificial neural network, BP-ANN) models were used to estimate the content of total acids in fermentation broth of apple vinegar through image analysis. The correlation coefficient (RP), root mean square error of prediction (RMSEP) and residual predictive deviation (RPD) of the better SVR model were 0.8708, 0.0545 and 10.91, respectively. The results implied that the CSA had an excellent potential for quantitative monitoring of total acids in apple vinegar during fermentation.
This investigation was conducted during 2014, 2015 and 2016 in the field of the citrus experimental station in Ciano, the general corps of scientific agricultural researches. The growth and yield of ...orange trees (Washington navel 141) budded on seven citrus rootstocks (Sour orange, Troyer citrange, Carrizo citrange, Citrumelo 4475, Citrumelo 1452, Macrophylla and Cleopatra mandarin) and farmed since 1989 have been studied. The results for the average of yield showed that the trees grafted on Cleopatra mandarin (58.33 kg. tree-1) were significantly superior to those grafted on Macrophylla (34.17 kg. tree-1). Orange trees grafted on Citrumelo 4475 and Citrumelo 1452 were significantly superior to other treatments in trunk section area of the rootstock (922.41 and 841.02 cm2, respectively). The greatest fruit fresh weight was in trees grafted on Citrumelo 4475 (284.85 g. fruit-1) which were significantly superior to those grafted on Carrizo and Troyer citrange (232.49 and 236.06 g. fruit-1, respectively). The biggest total soluble solids (%) was in trees grafted on Carrizo and Troyer citrange (12.83% for both treatments) which were significantly superior to those grafted on Sour orangе and Macrophylla (11.5% for both treatments), while the greatest total acids (%) was by Sour orange (2.08%) without significant differences.
Carrot juice is a rich source of vitamins, carotenes, minerals, and other micronutrients with positive health effects. The 'Kamaran F1', 'Baltimore F1', 'Naval F1', 'Niagara F1', 'Flakkese 2 – Vita ...longa' varieties were included in the study conducted during the years 2021–2022. The study examined the influence of selenization on the selenium level and additionally also other qualitative and quantitative indicators in carrot juice. For a total of 50 mg/L of sodium selenate was applied. The process of making carrot juice involved cleaning and washing the roots, crushing, and pressing them, pasteurizing the juice for 5 min at 85 °C, and aseptic filling. In addition to the selenium content, quantitative parameters (1 - root average weight, total carrot roots yield, juice yield) and qualitative parameters (carotenoids, sugars, acids, total soluble solids) were monitored. Our findings revealed a higher selenium level in the carrot juice that followed this processing method. The average content of Se in fresh carrot juice without Se fortification was 14 μg/L, while in the fortified variant the content of Se in carrot juice was 186 μg/L (13-fold increase). In the pasteurized variant 11-fold increase of selenium was found in fortified variant. This indicates that this form of selenium is thermostable, meaning that the juice retains its composition, adding to its additional value. Based on the other assessed parameters the application of sodium selenate at the recommended dose did not significantly affect the height of the carrot yields, which is an important economic criterion.
•Conversion and presence of organic selenium in carrots, raw- and pasteurized juices.•13-fold Se level increase in the fresh and fortified carrot juice.•11-fold Se level increase in the pasteurized and fortified carrot juice.•This form of Se is thermostable under given conditions.•The application of Se didn't significantly negatively affect the height of the carrot yields.
The goal of this study was to determine whether the quality of fruit nectars and wines available on the local market is in accordance with the quality prescribed by the Rulebook. The research ...involves analysis of blueberry, strawberry, peach, apple and orange fruit nectars from two companies (C1 and C2), and samples of red wines from three wineries (W1-3). The following quality parameters were determined: soluble solids content (% Brix), actual acidity (pH) and titratable acidity in the nectars, and actual acidity (pH) and titratable acidity in the wines. All samples of fruit nectars met the prescribed % Brix requirements. Titratable acidity, expressed in g dm-3 citric acid, in C1 blueberry and strawberry nectars deviated from the values laid down in Rulebook 2 (Rulebook on the Quality of Fruit Juices, Concentrated Fruit Juices, Fruit Juice Powder, Fruit Nectars and Related Products- Official Gazette of RS Issue No. 27/2010). Deviations were detected in C2 orange nectar. The total acid content in the analyzed wine samples, expressed in g dm-3 of tartaric acid, corresponded to the values prescribed in Rulebook 1 (Rulebook on Quality and Other Requirements for Wine - Official Gazette Issues Nos. 54/99 and 39/2002, Official Gazette Issue No. 56/2003 - other Rulebook and Official Gazette Issue No. 87/2011 - other Rulebook and 26/2015 - other Rulebook).
The determination of alcohol, SO2, and total acids in wine through conventional laboratory techniques have some limitations related to the amount of the samples, analytical preparation of laboratory ...staff, and time to carry out the analysis. In recent years, spectroscopic and chromatographic methods have been proposed to determinate simultaneously multiple analytical parameters. The new methods claim the speed of analysis and easy execution. However, they need a validation process that guarantees the reliability of the results to be used in official determinations. This study aimed to evaluate the usefulness of FT-infrared reflectance (FT-IR) to quantify total acid, alcohol, and SO2 concentration in the wines. For this purpose, 156 DOC Italian wines were tested with IR technology, and results were compared to those obtained by official analysis methods. The comparison was performed using two non-parametric statistical methods: the Bland & Altman test and Passing & Bablok regression. Our results showed that the spectrophotometric methods make errors due to interfering contaminants in the sample that can be corrected by blank determination. Therefore, the spectrophotometric methods that use the infrared region of the electromagnetic spectrum can be used by the wine industry and regulators for the wine routine as an alternative to official methodologies.
The purpose of this study was to find out the effect of lime total acids on the characteristics ofintestine broiler base on its pH, digestive viscosity, and the number and hight of small ...intestineof villi. Atotal of120 male Lohmann broiler chicks with the average body weight of 45.29 ± 1.76g, were used in thisstudy which were then allotted into six groups. The six treatment groups consist of : animals feed with noadditional acid (PO) as negative control, animals feed with addition of 0.4% (w/w) commercial citric acid(P1) as positive control, and animals feed with additional of 0.2% (P2), 0.4% (P3), 0.6% (P4), and 0.8% (P5)total acids extracted from lime, respectively. This study was carried out using Completely RandomizedDesign with four replications. The results showed that lime total acids had a very significant effect(P<0.01) on the pH and digestive viscosity. However, no significant effect (P>0.05) was found on thenumber and height of the villi. The addition of 0.8% total acid on the animals fed give the best result on theintestinal characteristics compared to other treatments.
This study characterizes the fruit quality attributes and illustrates the differ-ences in biometrical characteristics, taste- and health-related compounds present in wild bilberry (V. myrtillus) and ...two commercial blueberry cultivars of V. corymbosum (‘Berkeley’ and ‘Bluecrop’). Fully ripened berries were evaluated for their biometrical characteristics (fruit weight, size, and index of fruit shape), taste compounds (sugars, sweetness index and total acids), and health-beneficial properties (total phenolic content and total antioxidant capacity). V. myrtillus exhibited significantly lower values of fruit weight and size in comparison to blueberry cultivars (0.47 g, 8.6 mm and 9.2 mm, respectively). Cultivar ‘Berkeley’ yielded the highest glucose and fructose contents (70.8 and 88.8 mg/g FW, respectively), and the sweetness index expressed similar trend achieving the highest value for this cultivar (279.2). Conversely, V. myrtillus contained abundant quantities of total organic acids as an important attribute of nutritional fruit quality (0.35 mg/g FW). Vaccinium species differ greatly in their total phenolic content and a very high value of total phenolics obtained in V. myrtillus (3.87 mg GAE/g FW) was 2-fold greater than those of cultivated blueberries. Total antioxidant capacity showed the greatest level for V. myrtillus (6.16 mg asc/g FW), probably reflecting similar expressed total phenolic content. Correlation coefficients between total phenolics and total antioxidant capacity ranged from r=0.89 (‘Bluecrop’) to r=0.95 (V. myrtillus and ‘Berkeley’).
Kiwifruit vary in acid content between 0.6 and 1.5% and the acid-sugar balance is an important characteristic governing the consumer preference. It is a common practice to analyse titratable acidity ...(TA) but we are aware of two different approaches. Juice can be squeezed from the fruit so that TA in grams per 100 g juice is reported, or alternatively a measured weight of tissue can be sampled. TA measurements in fruit grown in warm climates have also been shown to drop quickly (up to 50%) after only 1-2 months in storage. This could be a feature of either the methodology used (juice titration) or of the climate. We therefore compared titratable acidity measurements from juice and tissue samples from the same fruit in several different orchards in Italy and New Zealand. Although, juice TA declined by up to 30% after 4 weeks’ storage in one orchard, in a few orchards an increase in juice TA was observed during the same storage period. By contrast, the results for TA using a measured amount of tissue were much more stable and showed no significant difference after storage. It seems that the pronounced drop in titratable acidity reported in warm climates is a feature of the TA of the juice sample only. We recommend titrating a fixed amount of tissue as this measurement has previously allowed correlation with fruit taste and with orchard variations such as dry matter.
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