Effect of bleaching whey on sensory and functional properties of 80% whey protein concentrate

Abstract

Whey is a highly functional food that has found widespread use in a variety of food and beverage applications. A large amount of the whey proteins produced in the United States is derived from annatto-colored Cheddar cheese. Color from annatto is undesirable in whey and must be bleached. The objective of this study was to compare 2 commercially approved bleaching agents, benzoyl peroxide (BP) and hydrogen peroxide (HP), and their effects on the flavor and functionality of 80% whey protein concentrate (WPC80). Colored and uncolored liquid wheys were bleached with BP or HP, and then ultrafiltered, diafiltered, and spray-dried; WPC80 from unbleached colored and uncolored Cheddar whey were manufactured as controls. All treatments were manufactured in triplicate. The WPC80 were then assessed by sensory, instrumental, functionality, color, and proximate analysis techniques. The HP-bleached WPC80 were higher in lipid oxidation compounds (specifically hexanal, heptanal, octanal, nonanal, decanal, dimethyl disulfide, and 1-octen-3-one) and had higher fatty and cardboard flavors compared with the other unbleached and BP-bleached WPC80. The WPC80 bleached with BP had lower norbixin concentrations compared with WPC80 bleached with HP. The WPC powders differed in Hunter color values (L, a, b), with bleached powders being more white, less red, and less yellow than unbleached powders. Bleaching with BP under the conditions used in this study resulted in larger reductions in yellowness of the powders made from whey with annatto color than did bleaching with HP. Functionality testing demonstrated that whey bleached with HP treatments had more soluble protein after 10 min of heating at 90°C at pH 4.6 and pH 7 than the no-bleach and BP treatments, regardless of additional color. Overall, HP bleaching caused more lipid oxidation products and subsequent off-flavors compared with BP bleaching. However, heat stability of WPC80 was enhanced by HP bleaching compared with control or BP-bleached WPC80.

Effect of temperature and concentration on benzoyl peroxide bleaching efficacy and benzoic acid levels in whey protein concentrate

“…A norbixin destruction level of 90% approximates the bleaching efficacy of BP treatments reported previously in literature (Listiyani et al, 2011;Jervis et al, 2012;Jervis et al, 2015). The prediction equations generated in experiment 1 also predicted that approximately 5 mg/ kg soluble BP at 4°C would destroy 40% of norbixin in 1 h, which is equivalent to or greater than HP bleaching in previous literature (Jervis et al, 2012;Campbell et al, 2013;Jervis et al, 2015). The WPC80 powders were manufactured from liquid whey at 2 temperatures (4 and 50°C), with 5 mg/kg of each of the 2 commercial forms of BP.…”

“…To provide a colorless whey ingredient, colored liquid whey must be bleached; however, the use of chemical bleaching agents has detrimental effects, including off-flavor development, chemical residues, and protein functional changes (Listiyani et al, 2011;Jervis et al, 2012). There are currently 2 chemical bleaching agents approved for use in liquid whey in the United States, hydrogen peroxide (HP) and benzoyl peroxide (BP) (21CFR184.1366 and21CFR184.1157, respectively).…”

“…There are currently 2 chemical bleaching agents approved for use in liquid whey in the United States, hydrogen peroxide (HP) and benzoyl peroxide (BP) (21CFR184.1366 and21CFR184.1157, respectively). Bleaching of liquid whey has been extensively studied, and it has been consistently demonstrated that BP results in greater norbixin destruction and less lipid oxidation and subsequent off-flavors than bleaching with HP (Listiyani et al, 2012;Jervis et al, 2012;Fox et al, 2013;Jervis et al, 2015). Benzoyl peroxide reacts with oxidizable compounds in the liquid whey and is converted into water-soluble benzoic acid (BA).…”

Desenvolvimento, caracterização e análise sensorial de formulações alimentares com proteínas do soro de leite ou albumina para crianças

“…Além dos aspectos nutricionais, as proteínas do soro de leite possuem funções tecnológicas, que permitem sua ampla aplicação em alimentos e bebidas, melhorando propriedades como solubilidade, gelatinização, formação de espuma, tamponamento e emulsificação (JERVIS et al, 2012).…”

“…Diversos ingredientes, derivados do soro de leite, também podem ser incorporados em alimentos e bebidas, contribuindo para sua reutilização, tais como o soro de leite em pó, com concentração de proteína de 11 a 14,5%; o concentrado proteico de soro de leite (WPC -Whey Protein Concentrate), com teor proteico de 35 a 89%; e a proteína isolada de soro de leite (WPI -Whey Protein Isolate), que contém, no mínimo, 90% de proteína em sua composição (JERVIS et al, 2012).…”