Tinned vegetable

The iodination of industrially used salt raised the iodine content of rolls, bread, sausage, salted meat and tinned vegetables to a great extent (Table 9-4.13). Typical increases in iodine content were 15- to 17-fold for rolls and bread, 17- to 23-fold for sausage, and 40-fold for vegetables cooked with iodinated salt. 

Corundum (AljOj) Vegetable oil mists (except castor cashew nut, or similar irritant oils) Sucrose, Tin Oxide, Titanium Dioxide Silicoh Carbide... 

Many organic liquids, including oils (essential, animal, vegetable or mineral), alcohols, fatty acids, chlorinated hydrocarbons and aliphatic esters, are without action. The absence of any catalytic action of tin on oxidative changes is helpful in this respect. When, however, mineral acidity can arise, as with the chlorinated hydrocarbons containing water, there may be some corrosion, especially at elevated temperature. 

Fruit juices, meat products, milk and milk products, fish and most vegetables, in which tin is likely to be anodic to steel, can be handled open to the air in tinned steel vessels. Some corrosion of the tin occurs at rates similar to those found for pure tin and in due course retinning may be necessary. The alloy layer in hot-dipped tin coatings is cathodic to both tin and steel and, under aerated conditions may stimulate the corrosion of both metals, but this effect appears to be unimportant in practice. 

Foods such as meat, fish, and some vegetables contain sulfur-bearing amino acids that form volatile sulfur compounds during processing and storage. When these compounds react with iron, a black precipitate forms on the container and in most instances darkens the food. A small piece of aluminum welded to the tinplate can has been used to prevent container corrosion and sulfide staining in commercially canned hams. In this case, the aluminum acts as a sacrificial anode and stops the reaction with tin and iron that otherwise could occur at the small exposed tinplate areas (14). 

In fruit penetration studies 8 pounds of fruit were first thoroughly scrubbed with warm 10% trisodium phosphate solution and then rinsed thoroughly with distilled water. Citrus fruits, if depth of penetration into the peel was of interest, were peeled in longitudinal sections with a buttonhook peeler and the albedo or white portion was separated from the flavedo or colored portion. The separated peel was placed in pie tins lined with waxed paper and dried in a forced draft oven at 65° C. for 16 hours. The dried peel was then crushed and steeped for 48 hours in a measured volume of benzene sufficient to cover the sample. If, on the other hand, only the total amount of DDT in the peel was of interest, the fruit was halved and juiced on a power juicer. The pulp was removed, the peel sliced, and the sample dried and treated as before. Thin-skinned fruits, such as apples, pears, and avocados, were peeled with a vegetable peeler, cores or seeds were removed, and the pulp was sliced in thin slices. Pulp and peel were then dried and treated in the same way as the citrus peel. The steeping completed, the samples were filtered through Sharkskin filter paper and the volume of benzene recovered was noted. 

Biodiesel is a mixture of methyl esters of fatty acids and is produced from vegetable oils by transesterification with methanol (Fig. 10.1). For every three moles of methyl esters one mole of glycerol is produced as a by-product, which is roughly 10 wt.% of the total product. Transesterification is usually catalyzed with base catalysts but there are also processes with acid catalysts. The base catalysts are the hydroxides and alkoxides of alkaline and alkaline earth metals. The acid catalysts are hydrochloride, sulfuric or sulfonic acid. Some metal-based catalysts can also be exploited, such as titanium alcoholates or oxides of tin, magnesium and zinc. All these catalyst acts as homogeneous catalysts and need to be removed from the product [16, 17]. The advantages of biodiesel as fuel are transportability, heat content (80% of diesel fuel), ready availability and renewability. The... 

At present, Polish standards limit the content of tin only in food products packed in tin-coated containers, and in fruit and vegetable preserves, and products including such preserves, packed in other materials (Dz. U., 2003). The content of tin in products intended for children up to the age of three must not exceed 10 pg per g, and for other products it must not exceed 100 pg per g (for food in tin-coated packing) or 20 pg per g (for food in other types of packing). The Joint FAO/WHO Expert Committee established the PTWI value for tin as 14,000 pg per g (14 mg per g) of body weight (WHO, 1989). 

Lavoisier said that Phosphorus is met with in almost all animal substances and in some plants which, according to chemical analysis, have an animal nature.. . . The discoveiy that M. Hassenfratz has made of this substance in wood charcoal would make one suspect that it is commoner in the vegetable realm than has been thought tins much is certain that, when properly treated, entire families of plants yield it (37). Apothecary J. K. F. Meyer of Stettin wrote in 1784 that he had observed, several years previously, a permanent green color in the essences he prepared by digesting green herbs in copper vessels He concluded that phosphates in the leaves had reacted with the copper to form copper phosphate (38). 

He sees the true sulphur principle in all the sulphureous materials, for example metals dried by calcination to the point that they cannot be melted, or that they are vitrified into a scorious matter. When oil is added to these destroyed metals and heated, they regain their original form. The reason is that the vegetable oil takes the place of the oily or sulphureous matter of the mineral that the fire of calcination had evaporated we see this in all the calxes [les chaux] of the lesser metals but most clearly in those made of tin in the verve ardent ... 

Conventional tin and glass containers can be satisfactorily treated by steam or hot air. Paper, cardboard, and heat-sensitive plastics require subtler techniques. Experiments with Co60 gamma rays indicate that 200,000 r. are sufficient to inactivate vegetative contaminants, while the customary 2 X 10 r. are required for spore formers. These doses are considerably below those that would be expected to have any effect on the physical properties of these materials (Sec. IIIC5). 

The general character of Neumann s chemistry is practical rather than theoretical. It describes plainly and in considerable detail the occurrences, properties and preparations of a large number of mineral, animal, and vegetable products, and the value which it must have possessed at that time as a condensed encyclopedia of chemical facts is manifest. Neumann apparently accepts the phlogiston hypothesis without reservation. In the discussion of metals, which he divides into perfect metals—gold and silver imperfect metals—lead, copper, iron and tin and semimetals (not malleable)—mercury, bismuth, zinc, antimony, arsenic, he has this to say under the head of imperfect metals 7... 

Metallic smoke (fume) An emanation fiom heated metals or metallic ores, the particles being of specific geometric shapes. Such smoke is particularly damaging to vegetation in the neighborhood of zinc and tin smelters,... 

Initial attempts by Baker et al. [ 160] to determine the nonsystemic triphenyl tin-based fungicide fentin by HPLC were unsuccessful due to a lack of sensitivity and interference by coextractives. They therefore decided to investigate the applicability of spectrofluorimetry to this determination. Different extraction procedures are described for vegetables and cocoa products. For potatoes, for example, the grated potato is dried with anhydrous sodium sulfate and then Soxhlet-extracted with dichloromethane. 

Mercury- and tin-containing fungicides have been used to control diseases in fruit, vegetables and cereals. 

Most natural foods contain small amounts of tin but canned foods may have significant tin levels (NAS 1977 WHO 1980). Tin concentrations in fresh meats, cereals, and vegetables reportedly range from 0.1 to 1.0 mg tin/kg (Schafer and Femfert 1984). However, concentrations of tin ranging from 1.8 to 500 mg/kg have been reported in canned foods (Schafer and Femfert 1984 Sherlock 1987), with usual values below 100 mg/kg (NAS 1977). Foods from all- lacquered cans usually had tin concentrations below 25 mg/kg (WHO 1980). Current data from the Can Manufacturers Institute (CMI 1988) indicate that more than 90% of tin-lined cans used for food today are lacquered. Only light colored fruit and fruit juices are packed in unlacquered cans, since tin helps maintain the color of the fruit. 

Tin levels in fruits, vegetables, and juices were found to be higher when unlaquered cans were used [273]. Ethanol affects ICP-MS sensitivity for many elements. Sample preparation can affect the extent of the change in sensitivity. Internal standardization can be used to improve Pb concentration measurement accuracy in wine [274]. Isotope dilution analysis can be used for accurate concentration measurements in wine [275]. 

---