Vegetable Powders

In the case of certain vegetable powders, such as aloes, rhubarb, and opium, a mass suitable for rolling into pills may readily be formed by the aid merely of a small quantity of water, the powder being beat into a mass in a mortar during the gradual addition of the fluid. 

Where, however, the powder is of an unadhesive character, as is the case, for example, with many vegetable powders and metallic salts, some adhesive ingredient must be added to them to enable a mass of pillular consistence to be formed. 

For many vegetable powders castile soap answers very well, a small quantity readily imparting the necessary consistence. Resinous powders are particularly adapted to its use. 

Base notes contribute to the intrinsic taste of culinary products. This can be achieved by using basic savoury ingredients such as meat extract, bone-stock, yeast extract, fermented soy sauce, wheat gluten sauce, vegetable powders, herbs and spices. They provide a complex mixture of taste-active and taste-modifying compounds, some of them still unknown, in a typical and balanced composition. The basic taste can be... 

The chemistry of medicinal herbs is very complex. Not all the constituents present in the plant have therapeutic activity, some are poisonous e.g. pyrrolizidine and tropane alkaloids. Phytochemistry deals with study of chemical composition of the plant material (Phyto refers to plant). Plants are used in various forms varying from powders to extracts. Powder represents the drug in ground from and these types of preparations are considered to be crude. The Pharmacopoeia mentions standardised vegetable powders for therapeutic application. 

The dried vegetable products have shown the same organoleptic properties and moisture content as commercial vegetable powders for pharmaceutical use. Therefore, their active compounds do not lose their desirable characteristics after drying. 

Food products such as milk powder, coffee, tea, com syrup solids, starches, potatoes, eggs, cheese, fruit and vegetable powders, and so on are usually spray dried. All dryers can be fitted with cyclone collectors to collect the fine particles that do not settle in the dryer chamber. If necessary, the cyclone can be backed up with a fabric collector unless the powder is hygroscopic, in which case a wet scrubber may be used. Emission factors for cheese drying and whey drying in natural and processed cheese manufacture are shown in Table 53.23. 

With respect to the vegetable sources utilized, Ishida and Chapman determined the major carotenoid contents in several lyophilized vegetable powders, in particular, carrots for the carotene content (particularly P-carotene), white com for lutein, red tomatoes for the high ra j-lycopene isomer content and Tangerine tomatoes for the high tetra-cis-lycopene isomer content. The distinction between the two isomers is important because cfr-lycopene isomers are more hydrophilic than the tranj-isomers. 

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