Sugar/acidity ratio

Sugar-acid ratio -for fruit juice [FRUITJUICES] (Vol 11)... 

Table 7-7 Change in Sugar-Acid Ratio During Ripening of Blueberries ...

Fruity notes are related with a balanced sugar/acid ratio, without salt and nucleotides. Some fruits contain bitter or astringent notes. 

A three-year study monitoring the two major Champagne grape varieties (Millery et al., 1986) established a close correlation between the proline concentration and the [sugar/acid] ratio, i.e. the ripeness of the grapes (IM). The correlation... 

In enology, pulp maturity corresponds to an optimal sugar/acid ratio skin maturity is the stage at which the phenolic compounds and aromatic substances attain a maximum concentration. These two kinds of maturity can be distinguished, but the dissociation of the cell wall from the skin must be sufficiently advanced to permit easy extraction of these essential constituents. 

The length of the arabinan side chains present in subunit II may vary between 30 and 50 arabinose residues and several of these chains might be connected to the rhamnogalacturonan backbone which consists of only 8-10 sugar residues (ratio of rhamnose to galacturonic acid is 0.2 to 0.4). The arabinans might be connected directly to a rhamnose residue in the backbone or via one or more galactose residues [41]. 

Composition. Scientific data concerning liquids washed with water from orange juice finisher pulp was first published by Olsen et al. (30). They studied Brix/acid ratios, sucrose, reducing sugars, pH, pectic constituents, turbidity, pulp content, ascorbic acid, viscosity, and flavonoid content of experimental and commercial samples. Characterization of pulp-wash continued with publication of quality data (31), examination of pectic substances (32), microbiology (33), and comparison of pulp-wash with orange concentrate (34). 

It is demonstrated that a great many flavor compounds are formed in both model systems. On the other hand, phenylalanine formed by aldol condensations some special aroma products. Furthermore, the generation of thermal aroma compounds depend on the pH, the sugar/amino acid ratio and the temperature. 

Grapes are picked at optimum °Brix/acid ratio to ensure that the fruit has the best quality characteristics as to sugar, acid, and, in the case of black grapes, color. The intent is to receive the fruit in the best possible condition. 

For example, at pH 8.3, /J,/J-ANDPBA selects D-tartailc acid over D-sorbitol in the ratio 7.2 1. Upon lowering the pH to 5.6, the selectivity becomes irrefutable at a ratio 11,000 1. The pH dependency of these probes offers the potential for switchable sensing of sugar acids in complex mixtures. 

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