LOW SUGAR BAKERY JAMS WITH GELLAN GUM GUAR GUM MIXTURES - INFLUENCE OF COMPOSITION ON TEXTURE

Effects of gellan gum (GE), guar gum (G) and fruit (F) contents on texture of low sugar peach jams (30 degrees Brix) were studied. Thirty-six samples were prepared following a factorial design with three GE levels (0.05-0.1% w/w), four G levels (0-0.75% w/w) and three F levels (40-60% w/w). Instrumental texture was described by four parameters-hardness, rigidity, brittleness and adhesiveness-obtained from a single cycle puncture test in a Stevens Texture Analyser. GE is the composition factor with the strongest effect on both hardness and rigidity values. The effects of G and F on these parameters and GE-F interaction were also significant. Adhesiveness and brittleness were mainly governed by G content; effects of GE and F on adhesiveness and of GE on brittleness were significant. By Principal Components Analysis of texture data, it was found that the first component (66% of variability) is defined by hardness, rigidity and adhesiveness while the second (24% of variability) is mainly defined by brittleness. Increasing first axis scores were generally observed when GE increased, whereas second axis scores were mainly dependent on G content.