| Abstract: | Six strawberry varieties were evaluated as raw materials for industrial jam production. The investigation involved chemical, physical and sensory analyses of fresh and frozen/thawed fruits as well as jam at the time of production and after 3 months of storage. Among the varieties studied, Jonsok and Senga Sengana appeared most suitable, followed by Bounty and Tenira. The other varieties, Fructana and Totem, were less satisfactory for this purpose. Based on linear correlation analyses (P<0.05), the relevance of various parameters in evaluating fruits intended for jam production is discussed. The results disclosed pH, titratable acids and sugars of fresh fruits to be less important to jam quality. High contents of soluble solids and ascorbic acid were related to undesirable flavour properties of jams. Further, high levels of ascorbic acid adversely affected colour stability. Colour degradation in jams was parallel to flavour deterioration. It is concluded that the main emphasis should be given to characteristics of the final products rather than to characteristics of the fresh fruits. |
