A new kind of functional low-fat spread with hull-less pumpkin seed flour and fat replacer, in gel form, was defined in this work from a rheological and textural aspect. Observed spreads were systems with thixotropic flow behavior. All determined rheological parameters, except of yield stress, were affected by gel concentration and amount of gel. Increase in gel concentration caused increase in consistency of the spreads, their possibility to recover and contribution of elastic components in the structure of the spread. Increase in the amount of gel influenced the balancing factor and reduced influence in gel concentration. Statistically, this was confirmed as interaction of observed factors (P < 0.05). Textural parameters confirmed that more gel provided softer consistency and increased the spreadability that could be optimized by concentration of applied gel. Optimal observed properties exhibited the spreads with low concentrated gel ranging from 0.5 to 1% and with a 70% gel amount.
A press cake is the by-product of the mechanical process of oil extraction from pumpkin seeds. Hull-less pumpkin seed cakes are chemically and nutritionally valuable because of its high quantity of crude protein, fatty acids, minerals and energy. It is a very low-cost by-product. The exploitation of hull-less pumpkin seed cakes is poor, usually as animal feed. Possibilities of its application as a new low-cost biosorbent, for enzymatic protein isolation or as flour-like supplements are published. A number of low-fat spreads based on nuts, seeds and fat replacers are covered by published articles or patents. Oil seed cakes are an alternative to manufacturing low-fat spreads in terms of cost-effectiveness as well as for increased protein content. The presented results demonstrate the possibility of producing low-fat functional spread based on hull-less pumpkin seed flour, and a new form of utilization of this raw material.