EFFECT OF FORMULATION VARIABLES ON SENSORY QUALITY OF THERMO-REVERSIBLE FRUIT FILLING FOR FROZEN SEMI-FINISHED BAKERY PRODUCTS: MODELLING AND OPTIMIZATION

Abstract

Development of a food product requires integrated scientific and professional knowledge on the technological process, the final product and, the quality of the ingredients and their interaction. This research examined the effect of formulation variables on the sensory quality of a thermo-reversible sour cherry fruit filling, as well as the modelling and optimization of the variables for achieving the quality suitable for filling frozen semi-finished bakery products in industrial conditions. Each formulation for 15 model-samples was successively corrected, to achieve the appropriate sensory quality of the filling in finished products after baking. Their quality was evaluated by descriptive sensory and physico-chemical methods of analysis and compared. The basic formulation for the filling was defined after the successive production of 7 model-samples in laboratory conditions, their use in industrial conditions (puff pastry filling, shaping, quick freezing, storage for at least 24 hours at -18°C, baking and cooling to room temperature) and analysing their quality. Further formulation optimization included selecting: the type and amount of fruits (sour cherry, apple), food additives and cherry flavour for 8 new model-samples. The formulation and ingredients for the fruit filling production (30% sour cherry fruit, 30% apple puree, 58% sugar, 2% starch, 1% pectin, 0.03% firming agent E509, 0.03% acidity regulator E331, 0.025% cherry flavour) and quality parameters (dry matter 65%, acidity 0.85%, pH = 3.2-3.4) were defined. The fruit filling had appropriate sensory quality before and after baking of filled puff pastry: clear cherry-red colour, moderately firm consistency and stable volume, rich fruity aroma, and refreshing sweet-sour taste. The results also confirmed that the product was suitable for manual or machine filling of raw dough.