Juice chemical organic acids

Fruit and vegetable juices packed with 21-26 in. of vacuum and stored in uncoated aluminum cans caused severe corrosion as shown in Table III. The corrosion rate brought about by the juices depends more on the nature of the organic acid present and the buffering capacity of the juice than on the total titratable acidity (11). The use of coated aluminum containers considerably minimized corrosion problems. Product control under extended storage conditions may be achieved by using specific chemical additives. However, more work is needed in this area before final conclusions can be reached. 

The most common cause for the deterioration of concrete results from contact with inorganic and organic acids. Those that form soluble salts with calcium oxide or calcium hydroxide are the most aggressive. Typical compounds that can cause problems include sour milk, industrial wastes, fmit juices, some ultrapure waters, and organic materials that ferment and produce organic acids. Typical chemical families found in various types of chemical processing industry plants and their effect on concrete are shown in Table 18.1. 

Interaction Chemicals also offers two ion-exclusion columns for the separation of organic acids under the trade names ORH-801 and ION-300. Both stationary phases contain a 8-pm substrate which was optimized for its respective purpose by slight modifications of the chemical structure. While the separation properties of the ORH-801 column are very similar to those of the Dionex lonPac ICE-ASl, the ION-300 column was especially developed for the analysis of the Krebs cycle acids. Citric and pyruvic acid, succinic and lactic acid, as well as oxalacetic and a-ketoglutaric acid may also be successfully separated on this stationary phase. Such separations are of importance for the analysis of fruit juices, foods, and physiological samples. Figure 5-5 shows a respective separation of a standard mixture of organic acids, carbohydrates and alcohols, which resembles the matrix of a variety of beverages. 

PC/PE blends exhibit less tendency to stress-cracking as well as higher chemical resistance than polycarbonate. PC/PE blends are resistant to mineral acids, many organic acids, oxidants, many fats, waxes, oils, saturated aliphatic hydrocarbons, alcohols, milk, and fruit juices. They are not resistant to alkaline lyes, hot water (100 °C), amines, concentrated acids and bases, methanol, aromatic and halogen-ated hydrocarbons [86]. 

Because of their polymeric forms, alkylenebis(dithiocarbamates) are insoluble in water and most organic solvents. Additionally, they form strong complexes with different metal ions No extraction and chromatographic procedure has been reported for the parent compound of this chemical class. These compounds decompose readily under acidic conditions, for example by contact with the fruit or plant juice generated during sample preparation. 

Hydrochloric acid (HCL) is also known as hydrogen chloride, and in a less than pure form it is commonly called muriatic acid. It is used by many industries and is mainly obtained as a by-product of the organic chloride chemicals used in the manufacturing of plastics. It can be produced in pure form by exploding a mixture of hydrogen and chlorine gases. The stomachs digestive juice is a form of hydrochloric acid. 

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