Co-crystallization of lactose-flavonoids using Panela cheese whey

Unlike sucrose, lactose has been scarcely used to co-crystallize bioactive compounds. Furthermore, the co-crystallization of lactose and bioactive compounds using cheese whey directly as a lactose source has never been reported. This work aimed to study the co-crystallization process of lactose with flavonoids (rutin and quercetin) using Panela cheese whey as a lactose source. Our main results showed that flavonoids were successfully encapsulated with a ratio of ∼0.6 mg of flavonoids per gram of lactose crystals. The encapsulation efficiency of flavonoids was approximately 40%. Besides, the antioxidant activity of lactose-flavonoid co-crystals remained stable during their storage at room temperature for six months, reducing their IC50 values by 13–22%. Additionally, the co-crystal IC50 values decreased by only 11–20% after exposition to UV light for 10 min. In summary, Panela cheese whey can be used as a lactose source to co-crystallize this sugar with valuable bioactive compounds like flavonoids. •Lactose and flavonoids were successfully co-crystallized from Panela cheese whey.•Up to 60 mg of flavonoids were incorporated per 100 g of lactose crystals.•Flavonoid's encapsulation efficiency in lactose crystals was approximately 40%.•Lactose-flavonoid crystals had 17 times higher antioxidant activity than lactose.•UV irradiation only decreased 11–20% of lactose-flavonoid antioxidant activity.