Microorganism in food industry - Research Paper Example

Download file to see previous pages... Understanding these will possibly lead to much of the food production processes becoming shorter and less time consuming and will lead to less waste being produced. Some examples of foods that are produced using microorganisms include wine, cheese and bread. This paper will attempt to take a look at the microorganisms used in each of these foods and attempt to explain some of the mechanisms they utilise to achieve the result that humans desire. Winemaking Yeast in Wine Wine is a popular beverage where microorganisms play an important part. Wine has been consumed by humans for thousands of years (Okamura et al,1596) and the exact science of the wine making process is still being decoded. The quality of a wine is determined by whether the taste of that wine is original, the finesse, intensity of taste and by the microbiological and physicochemical stability (Dubourdieu, 1986; Noble, 1988; Rapp and Mandery, 1986; Schreier, 1979 of Colagrande, Silva and Fumi, 2) (Refer fig1). The microbiology behind the wine making process was only established less than 2 centuries ago by the work of Louis Pasteur (Bakalinsky and Penner, 1993 from Okamura et al,1596, Colagrande, Silva and Fumi,2). Yeasts are used extensively in wine making. There are approximately 700 species of yeast and sixteen of these species have been used in the process of making wine. These include Brettanomyces, Dekkera, Candida, Cryptococcus, Debaryomyces, Hanseniaspora, Kloeckera, Kluyveromyces, Metschnikowia, Pichia, Rhodotorula, Saccharomyces, Saccharomycodes, Schizosaccharomyces, Torulaspora and Zygosaccharomyces (Pretorius et al, 1999 of Swiegers et al, 142). Saccharomyces cerevisae is one of the most commonly used organisms for producing wine though other such as Pleurotus ostreatus, Flammulina velutipes and Agaricus blazei have recently been exploited (Okamura et al, 1596). A specific variety of grape can be exploited to produce some qualities of wines such as the distinctive smell (Dubourdieu 2000, Lambrechts and Pretorius 2000, Guth and Sies 2002, Swiegers and Pretorius 2005 of Swiegers et al, 142). Some of these distinctive volatile compounds which cause properties of a wine like smell arise from grapes. However, several are due to the action of yeast and bacteria during the production of wine. Taste is also greatly affected by the bacteria and yeast used during wine (Schreier, 1979; Simpson, 1979; Williams et al, 1989; Etievant 1991, Guth, 1998; Boulton et al, 1998; Rapp,1998; Dubourdieu, 2000; Ferreira et al, 2000; Lambrechts and Pretorius, 2000; Ribereau-Gayon et al, 2000a,b; Ortega et al, 2001; Guth and Sies, 2002 of Swiegers et al, 141). Grapes can only support the proliferation of few microorganisms (Henschke, 1997 of Swiegers et al, 142). This has been attributed mainly due to the selective pressure on the microorganisms due to the high content of sugar and the low pH of grape (Swiegers et al, 142). In addition, sulphur dioxide is usually added to the mixture during wine making and this adds even more selectivity to the microorganisms that can grow. Usually, oxidative microorganisms that may be harmful are limited due to the sulphur dioxide (Swiegers et al, 142). Once anaerobic conditions start to predominate during the winemaking process, even more microorganisms find the conditions unfavourable for growth and the production of ethanol further limits the types of microorganisms th ...Download file to see next pagesRead More