Fruit juice: single strength

The juice is recovered by inserting tubular knives into the fruit and squeezing the fruit. Alternatively, the fruit may be cut in half and squeezed. The recovered juice is put through a finisher to remove a portion of the pulp sacs, is heated to inactivate enzymes, and is either bottled as single-strength juice or concentrated for frozen concentrate. 

Dairy products are among the most Ca-dense foods. On average, milk contains 0.12% Ca by weight. Single-strength fruit juice beverages... 

Serial dilutions are recommended to ensure accurate measurements of highly concentrated, high density, or dried samples. Perform a weight-by-volume dilution with distilled water to obtain a single-strength solution (e.g., usually around 10° Brix for fruit juices unit hi,4), followed by a second dilution using 0.025 M potassium chloride buffer, pH 1.0. Both dilution factors must be considered when calculating monomeric anthocyanin content. 

For most applications, this is all the sample preparation that is necessary. Appropriate dilution is deceptive as it will vary from one commodity to another dependent on the number of anthocyanins in the matrix. The visual appearance and absorptivity of a sample is often not a sufficient indicator for HPLC peak height/area, as samples that have many anthocyanin peaks will need to be more concentrated than a sample that has the same total anthocyanin content but only a single major peak. Most anthocyanin-containing fruit juices will give a suitable response between single strength juice and a dilution of 1 5. 

Most anthocyanin-containing fruit juices will give a suitable response between single strength juice and a dilution of 1 5. 

Fruit juice Direct juice Rel. density 20/20°C Single-strength minimum Brix (direct juice) From concentrate Rel. density 20/20°C Single-strength minimum Brix... 

The pulp wash liquid from citrus fruit contains a higher amount of pectin than the single strength juice from the juice extractors. In most cases it must be treated enzymatically to achieve a sufficiently high concentration in the evaporator. In order to aid the concentration it is also commonly practised to centrifuge the liquid prior to evaporation to remove some or most of the insoluble solids from the liquid. 

Table III gives the protein content and percent haze readings for the single-strength apple juice and reconstituted apple juice concentrate samples. All of the samples showed high clarity as evidenced by the low haze readings, none having a propensity towards haze or sediment formation. A decrease in total soluble proteins was observed with increased storage time of apple fruit. Fining resulted in ca. 25-50% reduction in total soluble protein.

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