Investigation of the possibilities of using freeze-dried persimmon (diospyros kaki L.) powder as a sugar and wheat flour substitute in the production of bakery products

Persimmon is a fruit rich in many bioactive components, but its moisture content is high. Among the drying methods, freeze drying ensures that the bioactive components remain in the dry product with minimal damage. Freeze-dried persimmon powders were used as both flour and sugar substitute at 5%, 10% and 15% in cake and cookie production. Physical (weight, diameter, height, color measurement, and texture profile; in cakes additionally volume index, symmetry index, and uniformity index), chemical (moisture, ash, protein, fat, total dietary fiber), and sensory analyses were performed on the cake and cookie samples. Cake and cookie samples were stored and changes in weight, color and texture properties were also examined. Of the physical properties, weight, diameter, height, volume index, symmetry index and uniformity indexes exhibited values close to each other. In terms of color, L* value was determined lower in cakes and cookies with added persimmon powder compared to the control group. In terms of texture, a more fluctuating change was observed due to the addition of persimmon powder. In terms of chemical properties, dietary fiber ratio increased with the addition of persimmon powder. Moisture content also increased in cake and cookie samples where persimmon powder was used as a sugar substitute compared to the control sample. Protein, fat, and ash values showed fluctuating changes and were found to be numerically close to the control. In terms of sensory evaluation, cake and cookie samples with 5% persimmon powder added exhibited similar values. During the 21-day storage period, moisture content generally increased for both cookies and cakes, while a general decrease in hardness was observed in oven samples. In addition, a fluctuation tendency was observed in surface and external color and also weight during storage of cookies and cakes.