Original article Effect of whey protein addition on the nutritional, technological and sensory quality of banana cake Liziane R. Camargo, 1 Let  ıcia M. Silva, 1 Marina R. Komeroski, 1 Tarso B. L. Kist, 2 Carlos E. Rodrigues 2 Alessandro de O. Rios, 3 M edelin M. Silva, 4 Divair Doneda, 1 Helena de O. Schmidt 3 & Viviani R. Oliveira 5 * 1 Nutrition course, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil 2 Department of Biophysics, Institute of Biosciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 91501-970, Brazil 3 Institute of Food Science and Technology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 91501-970, Brazil 4 Federal Institute of Education, Science and Technology (IFRS), Rolante, RS, 95690-000, Brazil 5 Nutrition Department, Postgraduate Program in Food, Nutrition and Health, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil (Received 11 April 2018; Accepted in revised form 31 May 2018) Summary Whey proteins are of great nutritional and technological interest and their addition to bakery products can provide an increase in quality parameters such as texture, flavour and colour. In this study, four for- mulations were elaborated containing 0%, 10%, 20% and 30% of whey proteins. The physicochemical assessment included weight, height, volume, density, colour, hardness and centesimal and amino acid analysis. The sensory analysis included an affective test and buying intention. Height and volume after baking increased according to the amount of whey proteins added, while post-baking density decreased. Whey protein added to cakes presented a protein increase higher than 50% when compared to the stan- dard one. There was also a progressive increase in amino acids as quantities of whey proteins were added. The sensory showed a difference only in the 30% whey protein added cake, which proved to be less promising when compared to the other samples. Keywords Baking, physicochemical evaluation, sensory evaluation, whey protein. Introduction The protein and the amino acids intake in human nourishment are extremely important for the mainte- nance of our nutritional status. In this regard, proteins of animal are the most complete in terms of amino acids and can be used in different food formulations (Wu, 2016). Whey protein is derived from the milk through the caseification process in which casein coagulates. This process has been widely researched, distinguished and industrially used in search of functional ingredients, constituting an important source of high nutritional and technological quality proteins (Tan et al., 2015; Soares et al., 2018). Whey proteins can be classified as whey protein con- centrate, with protein composition from 35% to 80%; whey protein isolate containing at least 90% of pro- teins (Jeewanthi et al., 2015), and hydrolysed whey protein (Alves et al., 2014) which presents similar amounts to the isolate one, differing only by the hydrolysis process of the whey protein molecules, increasing its digestibility (Jeewanthi et al., 2015). At the beginning, many industries considered it a residue, which needs adequate treatment for its dis- posal, but this product presents important minerals, such as calcium, besides a significant amount of essen- tial amino acids and high protein value (Bosi et al., 2013), which makes it a very relevant ingredient that could be used in different food (Ganju & Gogate, 2017), Whey proteins technological benefits have also been analysed for being added to food and drinks, in order to increase solubility, gelation, emulsification, foam and tamponade capabilities to the formulations (Jee- wanthi et al., 2015). Industry also has been seeking to develop products with better functional attributes (Tan et al., 2015), and with high sensory quality, demanding studies about new ingredients like whey proteins (Zavareze et al., 2010). The addition of whey proteins in bakery could be relevant to be investigated and improve sensory *Correspondence: E-mail: vivianiruffo@hotmail.com International Journal of Food Science and Technology 2018 doi:10.1111/ijfs.13857 © 2018 Institute of Food Science and Technology 1