Effect of addition of starches of different botanical origin on the yogurt gel properties

The aim of the present study was to estimate an effect of addition of different starches (potato, maize, waxy maize and tapioca) on the sensoric properties as well as selected physicochemical properties of set-style yogurts. Sensoric evaluation comprised: color, taste, smell, consistency and general appearance. pH value, titration acidity, degree of syneresis by centrifuge and FIL/IDF methods, content of acetaldehyde and diacetyl were also estimated. All analyses were done on fresh yogurts and after 1 week and 3 weeks of storage at 4?C. It was stated that natural (not supplemented with any starch) yogurt and that fortified with waxy maize starch were characterized with the best sensoric properties. Moreover the latter one was found to maintain the highest acetaldehyde level after 3 weeks of storage. Also maize starch influenced higher level of this aromatic compound. Generally starch additives resulted also in lower acidity of yogurts during the first period of cold storage. Products with maize and tapioca starches demonstrated the highest resistance to whey separation.