Fruit vinegars obtained with the use of fermentation methods constitute an interesting type of functional food, which gains increasing recognition among consumers owing to its health- promoting qualities. The objective of the research study was to develop an innovative production technology of fruit vinegar utilising local strains of microorganisms derived from the culture collection of the Institute of Agriculture and Food Biotechnology (IBPRS). The raw material used for the vinegar biosynthesis included natural, cold-pressed apple juices sourced from farmers and small agricultural employers in the Voivodeships of Łódź, Śląsk (Silesia) and Mazowsze (Mazovia). The preliminary microbiological and physical-chemical analyses of juices were conducted in order to determine the following: count of mould and yeast, content of total extract, total sugars, acidity and pH, and content of cadmium and lead. The first production stage of vinegar was the anaerobic fermentation of apple juices to produce wines; in the wines produced the contents of alcohol and sugars were determined. The second stage was the biosynthesis of acetic acid with the use of apple wines and strains of acetic acid bacteria: Acetobacter pasterianus O4 and Acetobacter pasterianus MW3. During the biosynthesis process there were determined the content of alcohol and the strength of vinegar being produced. The technology of producing fruit vinegar as developed in the Food Quality Department of IBPRS made it possible to produce a product with strength ranging 3.3 ÷ 4.5 g of acetic acid per 100 cm3, with no chemical preservatives therein, showing an exceptional taste and aroma, and characterised by a high quality and nutritional value.
apple vinegar, functional food, fermentation process, Acetobacter pasterianus O4, Acetobacter pasterianus MW3