Liquid whey protein concentrates as primary raw material for acid dairy gels

Abstract

The replacement of dehydrated products such as whey protein concentrates and isolates (WPC and WPI) by liquid whey protein concentrates (LWPC) obtained by ultrafiltration can be an excellent alternative for the production of innovative dairy products. Thus, the aim of this work is to study the gelation properties of LWPC as raw material for acid-induced dairy gels. Acid-induced gels were produced with non-defatted LWPC, with or without fortification with skimmed milk powder (SMP), by bacterial fermentation and by glucono-δ-lactone (GDL) acidification. The fermented systems (yogurt type acid gels) produced weaker gel structures than the equivalent chemically acidified gels (dessert type acid gels). It was also observed that molecular rearrangement continues during cold storage and that fortification with SMP favoured gelation. Whey-based dairy gels obtained by fermentation or by glucono-δ-lactone acidification presented viscoelastic behaviour, appealing functional and nutritional properties, and their utilization can effectively contribute to the reduction of waste.