Use Of Chemical Preservatives Research Articles

Microbiology for Our Cultural Heritage

Microbiology investigates different microorganisms such as bacteria, fungi and algae and can analyze these organisms and their effect as biodeteriogens. Any microbially caused damage is strictly the result of microbial growth and microbial metabolism.After the diagnosis of a given situation, microbiology for the protection of our cultural heritage often has to set a prognosis regarding future ageing. Laboratory simulation experiments can help to provide answers to such questions. Different materials can be tested for their durability and resistance against bio-attack. Microbial growth results from the presence of organisms, availability of nutrients and favorable climatic conditions. Based on the analysis of the situation and taking further ageing into consideration, the need to intervene by conservation methods may be discussed. Chemical or physical methods can be applied to influence the natural durability and the deterioration process.Not only the use of chemical preservatives but also the presence of microbial mats can present a health risk for the restorer, conservator and science consultant.After the introduction (analysis, prognosis, and remedial treatment or conservation) some case studies are used to show the many possibilities of microbiology.

The sealed storage of moist flax with and without the use of chemical preservatives

SummaryThe suitability of ensilage as a means of preserving flax was investigated in a series of experiments in which 400 kg round bales of fresh flax were sealed in polyethylene film or plastic wrapped, with or without the addition of formic acid at 2.5 litre t‐1 or formalin at 5.6 litre t‐1 at the time of baling. Plastic wrapping provided a more effective seal than the bags which were easily punctured by the flax roots resulting in moulding and deterioration of the flax. Where the seal was not broken untreated flax underwent a clostridial fermentation and the pH fell to about 4.8. Cellulolytic activity degraded the flax fibre over a period of 3 to 6 months. The addition of formic acid reduced the cellulolytic activity provided the seal was not broken. In an experiment with 4 kg batches of flax of 65%, 40% or 25% MC sealed in polyethylene film, the addition of formic or propionic acids at 20 g kg‐1 DM did not prevent moulding and deterioration, but both NH3 and SO2 at 40 g kg‐1 DM preserved the physical structure of the flax. The NH3 darkened the flax and made it pliable and unscutchable while the SO2 bleached it and preserved the fibre without microbiological deterioration. The presence of acids on the moist stored flax appeared to inhibit the progress of normal water retting.

Predictive microbiology: Uses for assessing quality and safety of dairy products

Predictive growth models can be used to predict the shelf-life of products at any point from processing to purchase and to assist manufacturers devise suitable preservation strategies that inhibit the growth of spoilage and pathogenic organisms to an acceptable extent. A number of spoilage models for raw and pasteurized milk and cottage cheese are presented. In most fermented dairy products, the vigorous metabolic activity, of starter cultures prevents the growth of pathogens which limits the value of predictive models. Such modeling does however have application, particularly with respect to temperature abuse, in products such as pasteurized milk and cream where the perceived ‘naturalness’ of the product prevents the use of chemical preservatives. Two models describing the growth ofListeria monocytogenes are presented. It must be remembered that it is not sufficient to observe that a model appears to work: it is important to know why it works which emphasizes the need for continued fundamental studies on the physiology of microorganisms to underpin the more applied aspects of modeling research.

White Poison? The Social Consequences of Milk Consumption, 1850–1930

This paper seeks to adduce evidence on the social consequences of milk consumption in the period 1850–1930. It is shown that the poor quality of supply partly resulted from the nature of the marketing system, with adulteration and the use of chemical preservatives as other factors. Local authority regulation and central government legislation were very slow in controlling the cleanliness of production and sale. Milk was heavily contaminated with bacteria and was responsible for spreading a variety of diseases such as scarlet fever and tuberculosis. Infants not wholly breastfed were particularly vulnerable to diarrhoeal infections. Improvements such as pasteurization and bottling were slow to spread and are unlikely to have had much impact before the 1920s. Overall it is argued that ill-health caused by dirty milk was more serious, and its amelioration much later than previously documented.

Food irradiation and combination processes

International approval of food irradiation is being given for the use of low and medium doses. Uses are being permitted for different categories of foods with maximum levels being set between 1 and 10 kGy. To maximize the effectiveness of these mild irradiation treatments while minimizing any organoleptic quality changes, combination processes of other technologies with irradiation will be useful. Combinations most likely to be exploited in optimal food processing include the use of heat, low temperature, and modified-atmosphere packaging. Because irradiation does not have a residual effect, the food packaging itself becomes an important component of a successful process. These combination processes provide promising alternatives to the use of chemical preservatives or harsher processing techniques.

Metabolic aspects of antioxidants and preservatives.

The use of chemical preservatives serves to ensure the nutritional adequacy, palatability and safety of processed foods and beverages. The toxicity of some of the more ubiquitous antimicrobial agents (sorbic acid, p-hydroxybenzoates, sulphur dioxide) and antioxidants (propyl gallate, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT] is reviewed together with the role of metabolic data in assessing the 'safety-in-use' of these and other food-additives.

ChemInform Abstract: FOOD PRESERVATION: AN EXAMPLE OF THE APPLICATION OF NEGATIVE BIOTECHNOLOGY

The processing of foods to ensure the availability for the consumer of a wide variety of safe stable products provides a good example of the application of ‘negative biotechnology’. The objectives are to optimise the use of food resources by reduction or elimination of spoilage and waste, control food-borne health problems and develop ‘new’ food products. Our work describes the way in which technology is applied to control of biological, chemical and physical changes in foods. Examples are given to illustrate the implications for product shelf-life of the various process operations including inter alia, thermal and irradiation treatments, restriction of available water, use of chemical preservatives and the choice of packaging systems. Special emphasis is placed on the need to optimise quality and safety by the proper application of kinetic data for the various process operations. The concepts of quality assurance, ‘in-line’ process control and the use of microprocessor technology in the control of critical processes is considered. The work concludes with a look at the future requirements of the food processing industry in relation to developments in ‘negative’ biotechnology.

Food preservation: An example of the application of negative biotechnology

AbstractThe processing of foods to ensure the availability for the consumer of a wide variety of safe stable products provides a good example of the application of ‘negative biotechnology’. The objectives are to optimise the use of food resources by reduction or elimination of spoilage and waste, control food‐borne health problems and develop ‘new’ food products. Our work describes the way in which technology is applied to control of biological, chemical and physical changes in foods. Examples are given to illustrate the implications for product shelf‐life of the various process operations including inter alia, thermal and irradiation treatments, restriction of available water, use of chemical preservatives and the choice of packaging systems. Special emphasis is placed on the need to optimise quality and safety by the proper application of kinetic data for the various process operations. The concepts of quality assurance, ‘in‐line’ process control and the use of microprocessor technology in the control of critical processes is considered. The work concludes with a look at the future requirements of the food processing industry in relation to developments in ‘negative’ biotechnology.

The Binding and Preservation of Chinese Double-Leaved Books

The Chinese first adopted the flat book format in the tenth century A.D. and the stitched book placed in a cloth-covered case in the sixteenth century. The stitched double-leaved book was the end product of the Chinese bookbinder's effort to preserve the texts of his country's literature. The sheets of print were folded and stitched at the free edges in such a way as to form a fascicle which prevented strain at any particular point along the spine. These light-weight, soft-covered fascicles were contained in paperboard or wooden cases that were easily replaceable when damaged or worn. A number of practices contributed to the preservation of the books, including the use of chemical preservatives and insect repellents, well-planned bookroom arrangements, and skillful techniques employed in their repair. As a result of these sophisticated techniques, the Chinese book produced in the traditional format remains one of the most successfully preserved forms of book in the world.

PASTEURIZATION AND STERILIZATION OF BEER-A REVIEW*

Modern means of preventing the spoilage of beer by contaminating micro-organisms are compared with traditional techniques. Newer procedures include flash-pasteurization, sterile filtration and the use of chemical preservatives; aseptic bottling techniques, which are essential when sterility is achieved prior to packaging, are discussed. All known methods influence, in some measure, the properties of beer and the choice of a suitable technique is greatly dependent upon the precise nature of the product involved.

Gradient Balance Method for Specific Gravity Determination in Milk

The accuracy of the immiscible gradient balance method for determining the specific gravity and solids-not-fat (SNF) of milk was compared with the Watson lactometer and gravimetric procedures. Observations were also made to verify the effect of the breed of animal, stage of lactation, use of chemical preservatives, and effect of sample heat-tempering upon the accuracy of the method. The gradient balance method gave results slightly lower than those obtained with the Watson and gravimetric procedures. Results from the method gave greatest variation from the Watson technique in milk produced by the Jersey breed or in late lactation. Formalin preservative or prior heat-tempering of the sample did not affect the results.

Simplified Collection and Refrigeration of Twenty-Four-Hour Urine Specimens

No extract is available for articles shorter than 400 words.

British Food Journal Volume 27 Issue 3 1925

Whatever views may be held with regard to the question of the total prohibition or otherwise of chemical preservatives in foods, there can be little doubt that the broad theory underlying the recommendations of the Departmental Committee is perfectly, sound and consonant with the best interests of the public and the honest manufacturer. The use of chemical preservatives of any kind is undesirable, and if permitted at all, such preservatives should be restricted to substances which are not foreign to the human body. Referring to the various articles and letters which have recently appeared in The Times, Professor F. Gowland Hopkins, D.Sc., F.R.S., F.I.C., observes:—

The Prevalent Use of Chemical Preservatives in Foods, by ARNOLD ROWSBY TANKARD, F.I.C

The Prevalent Use of Chemical Preservatives in Foods, by ARNOLD ROWSBY TANKARD, F.I.C

The Use of Chemical Preservatives in Foods

The Use of Chemical Preservatives in Foods