Sugar Reduction Strategies in Sponge Cake: Impact on Sensory Properties and Consumer Perceptions

Reducing sugar in food products for food manufacturers causes many challenges. However, food product reformulation must have minimal changes in sensory attributes to ensure consumer acceptability. One product of focus within the “sugar reduction strategy” is cakes. This study aims to (1) determine sensory evaluation comparison of control (31% sugar), reduced sugar (25% sugar) and sugar-replaced cake samples (18% sugar) and (2) identify consumers’ perceptions of acceptability of cake portions. Cakes were prepared using eggs, self-raising flour, cake margarine, water, baking powder, caster sugar and sugar replacer (where applicable). The cake batter was portioned into bun cases 20–25 g, then baked in an oven at 180°C for 8–10 min, cooled and frozen before sensory evaluation. Participants were recruited via email, word of mouth and social media platforms whereby, they were invited to take part to taste cakes containing sugar alternatives and offer opinions on cake consumption and portion sizes. Participants, aged 18+ years were recruited from Loughry Campus (n = 58) and Ulster University (n = 32) and presented with four blinded samples (1: control, 2: reduced sugar, 3: inulin sweetener, and 4: carbohydrate blend sweetener-replaced cakes, with 31, 25 and 18% sugar, respectively) in randomised order. Participants were asked to evaluate the samples on a hedonic scale of 1 to 9 (1: dislike extremely to 9: like extremely) for appearance, aroma, taste, texture, sweetness, and overall acceptability. The texture of the cake samples (n = 9) was analysed through a texture analyser (TA; XT plus 100C). The sensory evaluation showed the most preferred cake sample was the control (35.2%) with the carbohydrate blend sugar-replaced sample being the least (15.4%). A significant difference was found within the attributes of appearance, texture, sweetness, and overall acceptability between the cake samples. The highest-ranked cake sample for the attributes was the control sample, except for appearance whereby the reduced sugar sample was higher, but not significantly different. The overall acceptability had no significant difference between control, reduced sugar, and inulin, but the carbohydrate blend sample was significantly different (P = 0.025). The texture attribute for the control cake had the highest likability (6.44) and was significantly different to the carbohydrate blend sugar-replaced cake sample (P = 0.026) but had no difference from the other cake samples. There was no difference between the texture analyser results between the cake samples. A significant difference was found in portion control visuals presented to participants of three different portion weights of cake, 55, 100, and 150 g, and the most selected for acceptability was 55g (67.8%).