Showing papers in "Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment in 1990"

Nitrates, nitrites and N-nitrosocompounds: a review of the occurrence in food and diet and the toxicological implications.

Abstract: Data on occurrence of nitrate, nitrite and N-nitrosocompounds in food and drinking water, and on total dietary intakes are reviewed. Metabolic, toxicological and epidemiological studies are surveyed and the implications with respect to safety evaluation are addressed. It is concluded that, on the basis of recent long-term animal studies and of clinical experience in man, the current Acceptable Daily Intake (ADI) allocated to nitrate by the Joint FAO/WHO Expert Committee on Food Additives of 0-5 mg/kg body weight/day (expressed as sodium nitrate) might be increased to 0-25 mg/kg body weight/day. Based on similar criteria, the ADI for nitrite would be 0-0.1 mg/kg body weight/day (expressed as sodium nitrite). In view of the known carcinogenicity of N-nitrosocompounds, exposure to these compounds in food should be minimized by appropriate technological means, such as lowering the nitrite concentration in preserved foods to the minimum required to ensure microbiological safety and use of inhibitors of nitrosation like alpha-tocopherol or ascorbic acid. Further work is needed to define the minimal levels of nitrite in foods needed to inhibit outgrowth of Clostridium botulinum and toxin production.

A review of sulphites in foods: Analytical methodology and reported findings

Abstract: Sulphites in various forms have been added to foods for centuries. Their use became an issue of concern when certain sensitive individuals exhibited adverse reactions to sulphite residues in foods. Analytical methods were developed to monitor these compounds at the regulatory limit of 10 ppm. In this report, analytical methods for determining sulphites in foods are reviewed, along with a critique of their chemistry and procedural schemes. An assessment of the key features of each method category is presented together with some comparative data. The classification scheme used is based upon the fact that determination of the sulphite content of a food is influenced more by the treatment and cleanup of the test solution than by the final determinative step. Based on a 60-year database, the Monier-Williams procedure still remains the method of choice.

Food applications of sorbic acid and its salts.

Abstract: Because of their physiological inertness, their effectiveness even in the weakly acid pH range and their neutral taste, sorbic acid and its salts have become the leading preservatives in the food sector throughout the world over the past 30 years. The most commonly used products are sorbic acid itself (E200) and potassium sorbate (E202). In many countries sodium sorbate (E201) and calcium sorbate (E203) are also permitted. Sorbic acid is sparingly soluble in water, sodium sorbate has better solubility, and potassium sorbate is very freely soluble and can be used to produce 50% stock solutions. The soluble sorbates are preferred when it is desired to use the preservative in liquid form, or when aqueous systems are to be preserved. Sodium sorbate in solid form is unstable and very rapidly undergoes oxidation on exposure to atmospheric oxygen. It is therefore not produced on the industrial scale. Aqueous solutions of sodium sorbate remain stable for some time. Calcium sorbate is used in the manufacture of fungistatic wrappers because it is highly stable to oxidation, but this use is very limited. Sorbic acid and sorbates can be directly added into the product. The products can be dipped or sprayed with aqueous solutions of sorbates. Dusting of food with dry sorbic acid is also possible but less recommended because sorbic acid irritates the skin and mucous membranes. Sorbic acid and particularly calcium sorbate can be used as active substances in fungistatic wrappers. A general survey of the numerous uses of sorbic acid in the food sector will be given. Some fields of application will be discussed that are either unimportant or not permitted in the U.K.

Dietary intakes of some essential and non-essential trace elements, nitrate, nitrite and N-nitrosamines, by Dutch adults: estimated via a 24-hour duplicate portion study.

Abstract: Duplicate portions of 24‐hour diets of 110 adults have been analyzed for aluminium, cadmium, copper, lead, manganese, mercury, zinc, nitrate, nitrite and volatile N‐nitrosamines. The mean daily intake of copper (1.2 mg) is only about 50% of recommended values; mean daily intakes for manganese (3.3 mg) and zinc (8.4 mg) are adequate and marginal respectively with respect to recommended amounts. For the non‐essential elements Al, Cd, Hg and Pb, mean daily intakes of 3.1 mg, 0.01 mg, 0.002 mg and 0.034 mg were found, respectively. For Cd this amounts to 17% of the acceptable daily amount, for Al, Hg and Pb 5%, 5% and 8%, respectively. Since 1976–1978 the dietary intake of lead has been reduced by a factor three; for the other six elements daily dietary intakes are almost the same as in 1976–1978. Average nitrate intake was 52 mg NO− 3/day, about 25% of the ADI. Only 16 diets contained a measurable amount of nitrite. The highest daily intake (0.7 mg NO− 2) is less than 10% of the ADI. Volatile N‐nitrosamines ...

Ethyl carbamate (urethane) in alcoholic beverages and foods: a review.

Abstract: This IUPAC review covers the earlier studies of the 1970s on the analysis, occurrence and formation of ethyl carbamate (EC) in foods and alcoholic beverages, as well as the more extensive publications that have appeared since the renewed interest in EC in early 1986. In these latter studies, updated analytical procedures, including solid-phase extraction, capillary gas chromatography and mass spectroscopic detection, have become commonplace. These analytical methods are employed for regulatory and data-gathering purposes and provide extensive information on the occurrence of EC, much of which is presented in review. Distinct theories on the sources of EC, mechanisms for its formation and steps required to reduce its levels in stone-fruit brandies, wines and whiskies are summarized. These studies suggest separate pathways of EC formation for each of the three commodities.

Toxicology of sorbic acid and sorbates.

Abstract: Sorbic acid and its salts have been subjected to an extensive battery of tests, including acute, short‐term and chronic toxicity/carcinogenicity tests, two‐generation reproduction and teratogenicity studies. These studies show that sorbic acid and sorbates have a very low level of mammalian toxicity, even in chronic studies at up to 10% of the diet, and are devoid of carcinogenic activity. They are non‐mutagenic and non‐clastogenic in vitro and in vivo. The low toxicity is explicable by the fact that sorbic acid is metabolized rapidly by similar pathways to other fatty acids. In humans, a few cases of idiosyncratic intolerances have been reported (non‐immunological contact urticaria and pseudo‐allergy). The frequency appears low but there are too few reported data for an accurate assessment of the true incidence. In extreme conditions (high concentrations and temperature) sorbic acid may react with nitrite to form mutagenic products but these mutagens are not detectable under normal conditions of use, eve...

High‐temperature migration of antioxidants from polyolefins

Abstract: Migration rates of radiolabelled antioxidants, Irganox-1010 (I-1010) and Irganox-1076 (I-1076), were measured from low- and high-density polyethylenes (LDPE, HDPE) and polypropylene (PP) at temperatures up to 135 degrees C. Water, 8 and 95 per cent aqueous ethanol and corn oil were employed as food simulating liquids (FSL). The experiments were conducted in a high-pressure cell in a manner that allowed contact between the polyolefin plaque and the FSL only during the test period and not while being heated. The migrations of the antioxidants varied with the square root of time, and the Fickian diffusion coefficients could be correlated with temperature in an Arrhenius fashion. Under comparable test conditions, antioxidant migrations were largest from PP for aqueous simulants, but for non-aqueous simulants the highest losses were from LDPE. In both instances lowest losses were from HDPE. In most instances there was little difference between the migration behaviour of I-1010 and I-1076. A few tests were conducted to measure the antioxidant migrations to foods. The losses were usually larger than those to water but below those to corn oil.

Specifications for gum arabic (Acacia senegal); analytical data for samples collected between 1904 and 1989.

Abstract: The regulatory specifications for gum arabic (Acacia senegal) are superficial and inadequate to ensure that it is not adulterated with non-permitted gums from other botanical sources. Moreover, the existing specifications do not give the consumer the essential assurance, fundamental to food safety evaluation principles, that the nature and quality of gum arabic used in foodstuffs always conforms to that of the Test Article selected for the toxicological studies which justified the current status ('ADI not specified') of gum arabic as a permitted food additive. The availability of well-preserved gum arabic samples, collected between 1904 and 1939, has enabled invaluable data to be added to those derived from samples from the most recent crops. The resulting analytical data substantiate and greatly extend the quantitative information available previously for the chemical characterization of gum arabic for regulatory and trade purposes. The data confirm that good-quality commercial gum arabic was used previously as the Test Article. There is no evidence that the specific rotation of gum arabic has become significantly less negative in recent years.

Migration into food of polyethylene terephthalate (PET) cyclic oligomers from PET microwave susceptor packaging

Abstract: A quantitative method has been developed to measure the migration of polyethylene terephthalate (PET) cyclic oligomers from aluminized PET susceptor film‐type food packaging into several food types. Microwaveable French fries, popcorn, fish sticks, waffles and pizza sold in susceptor‐type packaging were purchased in local markets, cooked according to package instructions and analysed for PET oligomers. Appropriate food blanks were cooked in glass containers. Quantities of PET oligomers found in the foods ranged from less than 0.012 μg/g to approximately 7 μg/g.

Migration of plasticizer from poly(vinyl chloride) milk tubing

Abstract: Milk samples were collected from a dairy in Norway at various stages of the milking process in order to assess the extent of migration of di(2-ethyl hexyl)phthalate (DEHP) from plasticized tubing used in commercial milking equipment. In control milk samples obtained by hand milking, DEHP contamination was below 5 micrograms/kg, whilst for machine milking, concentrations in the milking chamber for each individual cow averaged 30 micrograms/kg and rose to 50 micrograms/kg in the central collecting tank. Retail pasteurized skimmed milk samples from Norway were found to contain 20 micrograms/kg DEHP, and two retail cream samples contained 1200 and 1400 micrograms/kg of DEHP, reflecting the association of plasticizer with the fat phase. Retail whole milks from the UK contained 35 micrograms/kg of DEHP. This contamination is believed to originate from environmental sources as DEHP plasticizer was not used in the milking equipment.

Migration testing of plastics and microwave-active materials for high-temperature food-use applications.

Abstract: Temperatures have been measured using a fluoro-optic probe at the food/container or food/packaging interfaces as appropriate, for a range of foods heated in either a microwave or a conventional oven. Reheating ready-prepared foods packaged in plastics pouches, trays or dishes in the microwave oven, according to the manufacturers' instructions, resulted in temperatures in the range 61-121 degrees C. Microwave-active materials (susceptors) in contact with ready-prepared foods frequently reached local spot temperatures above 200 degrees C. For foods cooked in a microwave oven according to published recipes, temperatures from 91 degrees C to 200 degrees C were recorded, whilst similar temperatures (92-194 degrees C) were attained in a conventional oven, but over longer periods of time. These measurements form the basis for examining compliance with specific and overall migration limits for plastics materials. The testing conditions proposed depend on the intended use of the plastic - for microwave oven use for aqueous foods, for all lidding materials, and for reheating of foods, testing would only be required with aqueous simulants for 1 h at 100 degrees C; for unspecified microwave oven use, testing with olive oil would be required for 30 min at 150 degrees C; and for unspecified use in a conventional oven testing with olive oil would be required for 2 h at 175 degrees C. For microwave-active materials, it is proposed that testing is carried out in the microwave oven using a novel semi-solid simulant comprising olive oil and water absorbed onto an inert support of diatomaceous earth. The testing in this instance is carried out with the simulant instead of food in a package and heating in the microwave oven at 600 W for 4 min for every 100 g of simulant employed. There is an option in every case to test for migration using real foods rather than simulants if it can be demonstrated that results using simulants are unrepresentative of those for foods. The proposed testing conditions were validated as being realistic by measurement of the specific migration of various components from different plastics into foods under actual conditions of use and comparing with migration into simulants. Migration of plasticizers from PVC and VC/VDC copolymer films was monitored for both microwave reheating and cooking of foods. Total oligomer concentrations were measured from poly(ethylene terephthalate) (PET) trays, and volatile aromatics from thermoset polyester trays, using both types of container in microwave and conventional ovens.(ABSTRACT TRUNCATED AT 400 WORDS)

The determination of glycyrrhizin in selected UK liquorice products

Abstract: The glycyrrhizin contents of 42 samples of liquorice‐containing confectionery, health products and raw materials have been determined by a standard (AOAC) HPLC technique. Confectionery levels ranged between 0·26 and 7.9 mgg−1, whilst contents in health products were 0.30–47. 1 mgg−1, the highest values being measured for throat pearls. Six geographically diverse samples of liquorice root contained similar (22.2–32.3 mgg−1) glycyrrhizin contents. Highest levels of glycyrrhizin were found in liquorice block (44–98 mgg−1) and extract powder (79–113 mgg−1). These analyses enable a mean daily intake of glycyrrhizin to be calculated for the UK. The figure (1 mg) is lower than those reported for the US and Belgium (3 and 5 mg, respectively). The significance of the levels of glycyrrhizin in UK confectionery, and the estimated daily exposure thereto, is discussed in the context of existing data on liquorice‐induced toxicity.

Fungal metabolites of sorbic acid

Abstract: A number of fungal detoxification reactions of sorbic acid have been reviewed. These include decarboxylation to give trans‐1,3‐pentadiene, esterification to give ethyl sorbate, reduction to give 4‐hexenol and 4‐hexenoic acid. It was shown that seven Penicillium species could convert sorbic acid into 1,3‐pentadiene whilst P. bilaii, P. fellutanum and P. glabrum did not. However, most Eurotium species were unable to bring about this conversion. Considerable differences in the resistance of two isolates of P. crustosum to sorbic acid were found. An isolate from coconut was more resistant than one isolated from hazelnuts. Both sorbic acid and caproic acid (hexanoic) brought about disorganization of the mitochondrial membranes in P. crustosum. It is suggested that these lipophilic acids inhibit growth by interfering with the electrochemical membrane potential across the mitochondrial membranes.

Release of formaldehyde and melamine from tableware made of melamine — formaldehyde resin

Abstract: The relationship between the concentrations of formaldehyde and melamine released into 4% acetic acid from dishes and bowls made of melamine‐formaldehyde resin was determined. The average concentrations in the migration solution after the sample had been treated at 60, 80, and 95 °C for 30 min with 4% acetic acid were 0.0 ± 0.1, 0.5 ± 0.4 and 3.0 ± 2.2 ppm, respectively for formaldehyde and 0.04 ± 0.07, 0.21 ± 0.20 and 1.19 ± 1.18ppm, respectively for melamine. The correlation between the concentrations of formaldehyde and melamine released at 95 °C was y = 0.4858x ‐ 0.2724 (r = 0.8860), where y is melamine concentration (ppm), x is formaldehyde concentration (ppm) and r is the correlation coefficient. The molar concentration ratios of formaldehyde to melamine (F/M ratio) were 15.4 ± 11.6 at 80 °C and 14.9 ± 10.1 at 95 °C. Hence the release of both migrants was affected by temperature but the F/M ratio was not affected. The release of both compounds was increased on repetition of the migration test at 95 ...

The determination of nitrate and nitrite in cured meat by HPLC/UV.

Abstract: A rapid strong anion exchange HPLC/UV procedure has been developed for the determination of nitrate and nitrite in a wide variety of cured meats. The accuracy of this technique has been confirmed by the good agreement achieved with the existing British Standard colorimetric method. The applicability and repeatability of the procedure has been established in a survey of over 200 samples. The agreement between duplicate determinations and their respective means averaged ±3.4% for nitrite and ±4.3% for nitrate as defined by the term [(a‐ b)/(a + b)]× 100% where a and b are the repeat determination values.

Incidence of mycotoxins in maize grains in Bihar State, India.

Abstract: A regular survey of some maize‐growing areas of Bihar state, India, for three consecutive years (September 1984 to September 1986) revealed heavy infestations of mycotoxin‐producing fungi with different maize samples Aflatoxin‐producing fungi had the highest frequency of occurrence in all the cases and aflatoxins were the most common mycotoxins elaborated by these fungi Maize samples of the Kharif crop had a greater incidence of aflatoxins (47%) than the samples of rabi crop (17%) Stored maize grains also had a high incidence of aflatoxins (43%) Most of the contaminated samples contained aflatoxins at levels above 20 μg/kg

The correspondence between U.K. ‘action levels’ for lead in blood and in water

Abstract: This paper considers whether the Department of the Environment's water lead concentration criterion for lead pipe replacement and action in individual cases, i.e. 50 μg/1 in any sample, is too high when set against the Department of Health's advisory action limit for blood lead concentration of 25 μg/100 ml. The relationships between blood lead and water lead concentrations found in the Glasgow and Ayr duplicate diet studies, together with unpublished data from Glasgow and Liverpool, indicate that over 10% of people exposed to an average water lead concentration of 100 μg/l (the earlier action level) would have blood lead concentrations above 25 μg/100 ml, as would about 4% of those exposed to 50 μg/1 (the Maximum Admissible Concentration in an EEC Directive). For adults, average water lead concentrations should not exceed 30 μg/1 to ensure compliance with the limit for blood lead, i.e. so that not more than 2% exceed 25μg/100 ml. However, for one of the critical groups, bottle‐fed infants (whose diet is ...

Evaluation of polyethylene terephthalate cyclic trimer migration from microwave food packaging using temperature-time profiles.

Abstract: The polymer polyethylene terephthalate (PET) is widely used for packaging food that will be heated or cooked in the PET container. A procedure was developed to predict the potential of PET to migrate from the container into the food. Migration experiments using crystallized polyethylene terephthalate (CPET) and corn oil were performed at 115, 146 and 176°C. From these experiments diffusion coefficients were calculated for the cyclic trimer in PET. By using an Arrhenius plot to obtain the diffusion coefficient and a temperature versus time plot of a microwave susceptor‐heated CPET tray, it was possible to predict migration of the cyclic trimer into corn oil under microwave conditions. Predicted values were in good agreement with measured results.

Survey of aflatoxin contamination of dried figs grown in Turkey in 1986.

Abstract: A total of 284 dried fig samples, collected from fields during drying, and from warehouse and processing units in the Aegean region of Turkey in 1986, were examined for aflatoxin contamination. Aflatoxin B1, B2, and G1 were detected in 4, 2, and 2% of the samples, respectively, which were of the lower grade of figs taken from the drying stage. The average aflatoxin levels in positive samples were estimated to be 112.3 (B1), 50.6 (B2), and 61.4 ng/g (G1). The samples collected from storage (64 samples) and processing units (14 samples) contained no aflatoxins. The results of this survey show that aflatoxin contamination of Turkish dried figs in 1986 was highly correlated with the poorer grade of fig.

Headspace analysis of benzene in food contact materials and its migration into foods from plastics cookware.

Abstract: Concentrations of benzene of 29 and 64 mg/kg were found in two samples of thermoset polyester compounded for the manufacture of plastic cookware. In collaboration with the suppliers of the materials, it was established that the benzene originated from the use of t‐butyl perbenzoate used as an initiator in the manufacture of the polymer. Samples of thermoset polyester made to the original formulations and thus contaminated with benzene showed migration levels of 1.9 and 5.6 mg/kg in olive oil after extraction for 1 hour at 175°C. Migration levels into olive oil at 175°C for samples produced with non‐aromatic initiator were <0.l mg/kg. Concentrations of benzene in thermoset polyester cookware purchased from retail outlets were 0.3 to 84.7 mg/kg. Low amounts of benzene (<0.01 to 0.09 mg/kg) were detected in foods when the articles were used for cooking in microwave or conventional ovens. Other plastics used for retail food packaging, such as polystyrene and PVC, which might utilise t‐butyl perbenzoate cataly...

Isotope ratio and isotope dilution analysis of lead in wine by inductively coupled plasma-mass spectrometry.

Abstract: The lead content of 12 wine samples was measured by inductively coupled plasma‐mass spectrometry using the methods of standard addition and isotopic dilution analysis. An additional wine sample was analysed by external calibration, standard addition and isotopic dilution analysis. The lead content of the wine samples was in the range 30–150 ng ml−1 and good agreement between the different techniques was observed. Analysis of lead isotope ratios revealed significant differences between Australian and European wines, reflecting the different isotopic composition of Australian lead.

Evaluation of a predictive mathematical model of di-(2-ethylhexyl) adipate plasticizer migration from PVC film into foods.

Abstract: The diffusion coefficient of the plasticizer di‐(2‐ethylhexyl)adipate (DEHA) in Cheddar cheese (D f ) was determined by measuring the extent to which DEHA penetrated cheese that was placed in intimate contact with artificially DEHA‐contaminated cheese. Slices (20 μm) of cheese from the boundary layer, into which DEHA had migrated, were microtomed at ‐40°C, and analysed for DEHA by gas chromatography (GC). Mean values of D f determined by graph fitting experimental and calculated data were 1.5 × 10−9cm2 s−1 at 5°C and 3.0 × l0−8cm2 s−1 at 25°C. The partition coefficient (K) of DEHA between cheese and PVC film was derived from the partition coefficients of DEHA between acetonitrile (ACN) and cheese lipid, ACN and cheese solid, and ACN and PVC film. The mean values of ? between cheese and PVC film were estimated to be 0.70 at 5 C and 0.58 at 25°C. The estimated values of Df and K were then used in a mathematical model (Till et al. 1982) to predict migration levels of DEHA into cheese. Good agreement with pre...

Determination of sulphadimidine in animal feedstuffs by an enzyme-linked immunoassay.

Abstract: An enzymeimmunoassay technique for the determination of sulphadimidine in animal feedstuffs has been developed. The antibody showed limited cross‐reactivity with other drugs, including sulphonamides, used as feed additives. Using spiked samples recoveries of 80–88% were obtained. The limit of detection of the assay was 70 ng/g.

Mycotoxin production in amber durum wheat stored at 15 and 19% moisture content.

Abstract: Ochratoxin A and citrinin developed in 11 kg parcels of amber durum wheat at 15% and 19% initial moisture content (MC) exposed to simulated bulk storage in a Manitoba granary for 60 weeks between July 1984 and September 1985. Other biotic and abiotic variables were monitored throughout the storage period. Ochratoxin A reached maximum levels of 11.8 and 0.11 ppm at 19 and 15% initial MC, respectively, during weeks 44-48; citrinin reached levels of 80.0 and 0.65 ppm at these respective moistures during the same period. The effect of 19% initial MC was significantly greater for the following variables: ochratoxin A, citrinin, Aspergillus flavus, Aspergillus glaucus group species, Alternaria species, Aspergillus versicolor, bacteria, fungal propagule count, seed germination, O2, CO2, moisture content, and fat acidity. Principal component analysis indicated that the first two components, describing greater than 60% of the variability in the data, partially defined the ecological relationships leading to mycotoxin production in the stored durum wheat system.

Acceptable daily intake and the regulation of intense sweeteners

Abstract: At the present time there are four intense sweeteners that are available in a number of countries: acesulfame-K, aspartame, cyclamate and saccharin. Extensive toxicity databases are available on each sweetener and these have been assessed by both national and international regulatory authorities. This review considers briefly the critical toxicity of each sweetener that is the basis for establishing the no adverse effect level in animal studies. The calculation of an acceptable daily intake (ADI) for human intake employs a large safety factor applied to the no-effect level. The magnitude of the safety factor for each sweetener is discussed in relation to the ADI values recommended by the Scientific Committee for Food in 1985.

Determination of ivermectin residues in swine tissues - an improved clean-up procedure using solid-phase extraction.

Abstract: A rapid and sensitive HPLC method has been developed for the determination of ivermectin in swine tissues The clean‐up procedure is based on solid‐phase extraction on a Bond‐Elut C8 cartridge The average recovery from spiked swine muscle tissue was 87% in the concentration range 2–20 μg/kg The method has a limit of detection of 05–1 μg/kg A survey of the levels in muscle tissues from 35 sanitary slaughtered sows was made Five samples were found to contain ivermectin at concentrations between 34 and 276 μg/kg A good correlation (r = 09696) was found between these results and those obtained using another established method

Lead in alcoholic beverages: a second survey.

Abstract: Results are presented of a survey of lead in beers and wines. Evidence of low level lead contamination of draught beer was found in an earlier survey conducted previously but remedial action initiated by the Brewers' Society has apparently been successful in reducing this contamination. The position in respect of lead contamination of wine is less satisfactory. Wine poured from bottles which have been fitted with tin-coated lead closures may sometimes become contaminated by deposits of lead salts produced by corrosion of the lead closure. Results of a survey of wines from lead-capped bottles show that for bottles sampled during 1985/1986 the lead concentration in 20 out of 100 samples exceeded 1000 micrograms/l (equivalent to the statutory limit for lead in wine of 1 mg/kg as sold). Such contamination could give rise to undesirably high intakes of lead. Action being taken to reduce exposure from this source is described.

The identification of Combretum gums which are not permitted food additives, II.

Abstract: Combretum gums, readily available at low prices in East and West Africa, may be offered for sale as 'gum arabic'. Vigilance is necessary to detect such misrepresentations because Combretum gums differ greatly from gum arabic (Acacia senegal (L.) Willd.) in terms of quality, solution properties and value. Moreover, because there is no toxicological evidence for their safety in use, Combretum gums are not included in any of the international lists of permitted food additives. Food manufacturers and regulatory authorities therefore require data that characterize Combretum gums so that their use in foodstuffs can be prevented. This paper presents such data for the gums from a further six Combretum species. All of these have negative optical rotations similar to that of food grade gum arabic. It is no longer sufficient, therefore, to rely solely on an optical rotation measurement to confirm the identity of gum arabic. The additional analyses necessary to differentiate between Combretum gums and gum arabic are discussed.

Migration of epoxidised soya bean oil into foods from retail packaging materials and from plasticised PVC film used in the home.

Abstract: Epoxidised soya bean oil (ESBO) is used as a plasticiser and heat stabiliser in a number of food contact materials, in particular in poly(vinyl chloride) (PVC) films and gaskets. The level of ESBO migration into foods has been determined using a combined gas chromatographic/mass spectrometric (GC/MS) analytical procedure. The study has included both the use of ESBO‐containing materials for retail packaged foods and the domestic use of plasticised PVC films for applications such as wrapping food and covering food for re‐heating in a microwave oven. Levels of ESBO in fresh retail meat samples wrapped in film ranged from < 1 to 4 mg/kg, but were higher (max. 22 mg/kg) in retail cooked meat. Migration into sandwiches and rolls from ‘take‐away’ outlets ranged from < 1 to 27 mg/kg depending on factors such as the type of filling and the length of the contact time prior to analysis. The levels of migration of ESBO into cheese and cakes were consistent with previous experience with plasticiser migration—direct co...

Studies on a toxic metabolite from the mould Wallemia

Abstract: While monitoring the occurrence of toxigenic moulds in foods, using a bioassay screen, it was shown that an isolate of Wallemia sebi produced toxic effects in several of the bioassays. The toxic metabolite was isolated and purified using solvent extraction, TLC and HPLC coupled with the brine shrimp assay to monitor the toxic fractions. The purified toxin, which we propose to call walleminol A, has been partially characterized by mass spectroscopy, nuclear magnetic resonance, ultraviolet and infrared spectroscopy. It can be provisionally interpreted as a tricyclic dihydroxy compound, C15H24O2, with structural features characteristic of a sesquiterpene with an isolated double bond, but further work is required to characterize this compound unequivocally. The minimum inhibitory dose of walleminol A in the bioassays is approximately 50 μg/ml, which is comparable with a number of mycotoxins such as citrinin and penicillic acid.