LWT - Food Science and Technology xxx (xxxx) xxx Please cite this article as: Franks Kamgang Nzekoue, LWT - Food Science and Technology, https://doi.org/10.1016/j.lwt.2020.110479 Available online 30 October 2020 0023-6438/© 2020 Elsevier Ltd. All rights reserved. Short communication Development of a functional whey cheese (ricotta) enriched in phytosterols: Evaluation of the suitability of whey cheese matrix and processing for phytosterols supplementation Franks Kamgang Nzekoue a , Alessandro Alesi b , Sauro Vittori a , Gianni Sagratini a , Giovanni Caprioli a, * a School of Pharmacy, University of Camerino, Via Sant’Agostino 1, 62032, Camerino, Italy b Sabelli S.p.A., Zona Ind.le Basso Marino, 63100, Ascoli Piceno, Italy A R T I C L E INFO Keywords: Dairy product Functional food Phytosterols Ricotta cheese Stability ABSTRACT This study aims to evaluate the suitability of whey cheese (ricotta) and whey cheese production process for phytosterols-enrichment. Therefore, the phytosterols stability of ricotta cheese was assessed during cheese processing (85 ◦ C for 60 min) and storage (4 ◦ C for 4 weeks). Given the novelty of the food matrix used, it was necessary to develop an innovative analytical method for sterols determination in enriched ricotta cheese. The developed HPLC-DAD method showed good linearity (R 2 ≥ 0.9956) and reproducibility (0.4–7.6%), while extraction recoveries ranged between 83.7% and 84.6%. Phytosterols showed a good heat-stability in ricotta cheese matrix during cheese processing (87.0–89.7) %. Moreover, the functional cheese showed a homogeneous phytosterols distribution and maintained its potential bioactivity during its shelf-life since no signifcant varia- tion of phytosterols levels was observed during storage (0.83 ± 0.03) g/100 g. 1. Introduction The global awareness of high LDL-cholesterol guided to the devel- opment of different food products enhanced with functional molecules such as phytosterols, which are claimed to lower cholesterol levels. Phytosterols are endogenous components of plant cells with molecular structures similar to cholesterol (Liwa, Barton, Cole, & Nwokocha, 2017; Villegas & Sanchez-Taínta, 2017) (Fig. S1). They are competitive in- hibitors of cholesterol uptake by different mechanisms including the displacing of cholesterol from mixed micelles in the intestine, the reduction of cholesterol re-esterifcation in enterocytes, and the increase of the effux of cholesterol from enterocytes to the intestinal lumen through the expression increment of cholesterol transporter proteins (ABCG5, and ABCG8) (Botelho et al., 2014). Therefore, to exploit the associated health claims (Regulation (EU) No 376/2010), different functional dairy products enriched in phytos- terols have been developed with attention given to dairy beverages such as milk and yogurts. However, the constant need to innovate in this sector requires the development of original products using new vehicles for phytosterols supplementation. In this perspective, whey cheese such as ricotta could represent an alternative food matrix for phytosterols enrichment. Ricotta cheese is an unripened whey cheese with high water content, obtained by whey proteins coagulation after acidifcation (lactic acid, citric acid) and heat-treatment (85 ◦ C–90 ◦ C) (Camerini et al., 2016; Rubel, Iraporda, Gallo, Manrique, & Genovese, 2019). To our knowl- edge, among the few studies that have focused on cheese enriched with phytosterols (Giri, Kanawjia, & Rajoria, 2014; Ningtyas, Bhandari, Bansal, & Prakash, 2018; Pega et al., 2016), no study has assessed the possibility to use whey cheese as a food matrix for phytosterols sup- plementation. Therefore, the present study aims to assess the suitability of ricotta cheese for phytosterols fortifcation. The innovation in the food matrix tested, requires the development of new extraction and HPLC-DAD methods to identify and quantify phytosterols in the ricotta matrix. Moreover, the recoveries of the extraction method and the validation of the analytical method were assessed. Then, the practica- bility of industrial-scale production was evaluated and the effect of ricotta matrix on phytosterols stability was studied during heat-processing and storage. Furthermore, the homogeneity of phytos- terols distribution in ricotta cheese was also studied. * Corresponding author. E-mail address: giovanni.caprioli@unicam.it (G. Caprioli). Contents lists available at ScienceDirect LWT journal homepage: www.elsevier.com/locate/lwt https://doi.org/10.1016/j.lwt.2020.110479 Received 6 July 2020; Received in revised form 26 October 2020; Accepted 28 October 2020