Advantages of the KDS/BCA Assay over the Bradford Assay for Protein Quantification in White Wine and Grape Juice

2014 ◽  
Vol 66 (2) ◽  
pp. 227-233 ◽  
Author(s):  
Diana Gazzola ◽  
Simone Vincenzi ◽  
Gabriella Pasini ◽  
Giovanna Lomolino ◽  
Andrea Curioni
2004 ◽  
Vol 49 (1) ◽  
pp. 49-57
Author(s):  
Branislava Sivcev ◽  
Dragoslav Cvetkovic ◽  
Nevena Petrovic ◽  
Ivana Popadic

In two wine-growing areas with different climatic characteristics 12 cultivars intended for the production of white wines were studied. The climatic characteristics include: mean annual air temperatures, mean vegetation air temperatures, heliothermal coefficient, hydrothermal coefficient and active temperatures sum from the moment of the growth of shoots to their full maturity for each studied cultivar. Elements of buds fruitfulness (6 features in total), yield, cluster mass, sugar quantity and grape quality were observed in both localities. In the vineyards of Grocka and Kutina high yielding varieties Ugni blanc and Dimyat can be grown with great success. Italian Riezling produced higher yields and better quality of unfermented grape juice in the vineyards of Grocka in comparison with the vineyards of Kutina. Pinot blanc in both localities was characterized by high yield, but the quality of unfermented grape juice was better in the vineyards of Grocka. Variety Rkaciteli produced high yield and good quality of unfermented grape juice in the experimental period in the vineyards of Kutina.


Author(s):  
Zirui Ray Xiong ◽  
Anqi Chen ◽  
Glycine Zhujun Jiang ◽  
Alisha G Lewis ◽  
Christine D Sislak ◽  
...  

Wine and alcoholic apple cider are commonly back-sweetened with unpasteurized juice to produce fresh, natural, and palatable sweetened alcoholic beverages. Foodborne pathogens may be introduced from unpasteurized juice into alcoholic beverages through this back-sweetening process. Although pathogens generally do not survive under low pH conditions or high alcohol environment, the die-off of these pathogens has not been established to ensure the safety of the products. To determine the safety of these back-sweetened beverages, we evaluated the survival of three common foodborne pathogens, E. coli O157:H7, Salmonella enterica , and Listeria monocytogenes in modified white grape juice and apple juice models. White grape juice and apple juice were modified with hydrochloric acid/sodium hydroxide and ethanol to achieve conditions that are similar to the back-sweetened white wine and alcoholic apple cider. Pathogen cocktails were inoculated separately into modified juice models and their survival in the juice models were recorded over a 96-hour period. Our results show that a combination of low pH and high ethanol content resulted in a faster pathogen die-off compared to higher pH and lower ethanol conditions. The holding times required for different combinations of pH and ethanol concentration for each juice model to achieve 5-log reduction were reported. This research provides data to validate pathogen die-off to comply with Juice HACCP 5-log pathogen inactivation requirements for back-sweetened wine and alcoholic apple cider.


1977 ◽  
Vol 60 (3) ◽  
pp. 739-740
Author(s):  
Herb L Wildenradt ◽  
Paul A Stafford

Abstract Further experience with the white wine colorimeter has demonstrated that this instrument provides a simple and reproducible method of color measurement for both finished and unfinished white wines and white grape juices. In view of the proven accuracy and utility of the white wine colorimeter, the method specifying this instrument, 11.B01–11.B02, has been adopted as official final action.


Gels ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 43
Author(s):  
Dario Lucas Helbing ◽  
Leopold Böhm ◽  
Nova Oraha ◽  
Leonie Karoline Stabenow ◽  
Yan Cui

Despite the availability of a wide range of commercial kits, protein quantification is often unreliable, especially for tissue-derived samples, leading to uneven loading in subsequent experiments. Here we show that the widely used Bicinchoninic Acid (BCA) assay tends to underestimate protein concentrations of tissue samples. We present a Ponceau S staining-based dot-blot assay as an alternative for protein quantification. This method is simple, rapid, more reliable than the BCA assay, compatible with biological samples lysed in RIPA or 2x SDS gel-loading buffer, and also inexpensive.


2020 ◽  
Vol 608 ◽  
pp. 113904 ◽  
Author(s):  
Javiera Cortés-Ríos ◽  
Ana María Zárate ◽  
Juan David Figueroa ◽  
Joaquín Medina ◽  
Eduardo Fuentes-Lemus ◽  
...  

2019 ◽  
Vol 245 (12) ◽  
pp. 2697-2703
Author(s):  
Lorenzo Guerrini ◽  
Luca Calamai ◽  
Alessio Cappelli ◽  
Giulia Angeloni ◽  
Piernicola Masella ◽  
...  

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 554
Author(s):  
Mariona Gil i Cortiella ◽  
Cristina Ubeda ◽  
José Ignacio Covarrubias ◽  
V. Felipe Laurie ◽  
Álvaro Peña-Neira

Recently, the use of alternative vessels to oak barrels during winemaking has become increasingly popular, but little is known about their impact on the chemical composition of the resulting wines. To address this issue, a Sauvignon Blanc wine was elaborated from the same grape juice by using cylindrical stainless-steel tanks, oval-shaped concrete vessels, oval-shaped polyethylene vessels, and clay jars in triplicate. Each vessel was used for alcoholic fermentation and the aging of wines over its own lees. Wines elaborated in concrete vessels showed the highest pH and the lowest titratable acidity, most likely related to the observed release of inorganic compounds from the concrete walls. Little effect of the vessels was seen on the wine color and phenolic composition. Wines elaborated in clay jars showed the highest turbidity and the highest content of soluble polysaccharides, while those made using cylindrical stainless-steel tanks showed the highest content of volatile compounds. Despite the observed differences, all of the vessels tested seem suitable for white wine production since every wine showed chemical features that corresponded with the quality standards of Sauvignon Blanc wines.


2010 ◽  
Vol 93 (1) ◽  
pp. 2-11 ◽  
Author(s):  
Nerea Argarate ◽  
María Arestin ◽  
Javier Ramón-Azcón ◽  
Begoña Alfaro ◽  
Alejandro Barranco ◽  
...  

Abstract The main objective of this paper is to address the performance of immunochemical assays for the detection of the residues of three pesticides [atrazine, bromopropylate, and 2,4,6-trichlorophenol (TCP)] in real winery samples, such as wine, grapes, and grape juice. Different approaches have been evaluated to minimize interferences from the matrixes, and suitable working protocols have been established in order to achieve the necessary LODs, accuracy, and precision for real samples. A simple dilution of the sample proved to be sufficient for the determination of atrazine and bromopropylate in red and white wine and grape juice at the required levels of concentration. However, for TCP, an SPE procedure has been optimized using amino cartridges. The recoveries were above 85% in all cases, and the LOD values were below the parts per billion level, except for bromopropylate, which ranged between 2 and 50 µg/L, depending on the matrix. The grape matrix effect could be resolved by a simple extraction with methanol. Complete recoveries were obtained, and the final measurement procedures were able to determine selected pesticides below their maximum residue levels. The newly developed methods have been compared with standard chromatographic methods.


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