Mould spoilage

An alternative form of non-carbonated beverage comes in form-fill-seal plastic containers, which are typically square or round section cups with foil or plastic laminate lidding. Such products are difficult to produce to a quality that will satisfactorily compete with the shelf fife of aseptic foil/laminate packs. Fonn-fill-seal containers leave their contents vulnerable to oxidative degradation and are especially at risk of mould spoilage. The packs can be produced in aseptic conditions but the products are typically chemically preserved. 

Synthetic colours are normally so intense that they must be diluted considerably for them to be readily measured and dispersed into the product. If colour solutions are made up in the factory they have to be made up not more than 24 hours before use to avoid mould spoilage. The pre-prepared colour solutions have a permitted preservative or are made up in glycerine, propylene glycol or propan-2-ol. These non-aqueous solvents inhibit mould growth. 

Guynot, M.E., Ramos, A.J., Sanchis, V., and Marin, S. 2005. Study of benzoate, propionate, and sorbate salts as mould spoilage inhibitors on intermediate moisture bakery products of low pH (4.5-5.5). International Journal of Food Microbiology 101 161-168. 

Legan, J.D. 1993. Mould spoilage of bread The problem and some solutions. Int. Biodeterior. Biodegrad 32, 33-53. 

Aspergillus niger s very frequently isolated from sun-dried products, such as vine fruits, dried, smoked and cured fish, biltong, cocoa beans and spices. It sometimes causes kernel rot in cashews and is one species causing thread mould spoilage of cheese (Hocking Faedo, 1992). 

Hocking, A.D. Faedo, M. (1992) Fungi causing thread mould spoilage of vacuum packaged Cheddar cheese during maturation. Int. J. Food Microbiol. 16, 123-130. 

Gerez, C. L., Torino, M. I., Rollan, G., Font de Valdez, G. (2009). Prevention of bread mould spoilage by using lactic acid bacteria with antifungal properties. Food Control, 20, 144-148. 

Preservatives may inelude disinfeetant and antiseptic chemicals together with eertain compounds used almost exclusively as preservatives. They are added to mar industrial, including pharmaceutical, products which may, by their nature, support the growth of bacteria and moulds causing spoilage of the product and possibly infection of the user. In the field of pharmaceutical preservation, addition of an inhibitory substance to a multidose injection (Chapter 21) or the prevention of growth in aqueous suspensions ofdmgs intended for oral administration (Chapter 18) are prime examples. 

Moulds and yeasts show varying responses to biocides. These organisms are often important in the pharmaceutical context because they may cause spoilage of formulated products. Various types of protozoa are potentially pathogenic and inactivation by biocides may be problematic. Viral response to biocides depends upon the type and structure of the virus particle and on the nature of the biocide. 

If juice is to be sold as not from concentrate it is usually screened and pasteurised immediately after pressing - an operation with two main objectives. The first is to control the growth of spoilage micro-organisms that live on the fruit surface (mainly yeasts and moulds). The second is to destroy the pectolytic enzymes that occur naturally in fruit that would otherwise break down the cloudy nature of the juice. If, however, a clear juice is required (e.g. apple or raspberry), enzymes can be added to accelerate this natural process. 

The storage condition of raw materials, particularly hygroscopic substances, is important, and as a minimum water activity (Aw) of 0.70 is required for osmophilic yeasts, 0.80 for most spoilage moulds and 0.91 for most spoilage bacteria, precautions should be taken to ensure that dry materials are held below these levels. Some packaging used for raw materials, such as unlined paper sacks, may absorb moisture and may itself be subject to microbial deterioration and so contaminate the contents. For this reason polythene-lined sacks are preferable. Some liquid or semi-solid raw materials contain preservatives, but others such as syrups depend upon osmotic pressure to prevent the growth of os-mophiles, which are often present. With this type of material it is important that they are held at a con-... 

Microorganisms may have both positive and negative effects on foodstuffs. They may cause spoilage of foodstuffs and some, for example the typical food poisoning pathogens Salmonella, Staphylococcus aureus etc.), may even poison it. Moulds too may form toxic substances [7-9]. 

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