Ultrafiltration whey protein concentrate as a substitute for egg white in pie topping meringue

ABSTRACT

The suitability of ulatrafiltration whey protein concentrate [UF-WPC] as a partial or total replacement of egg white [EW] in meringue making was studied. Fresh EW was proportionally substituted with 25, 50, 75, or 100% [w/w] of UF-WPC, which was previously adjusted to pH 9.5 using NaHCO[3] or Na[2]CO[3], warmed indirectly to 60°C and cooled to the room temperature [22 +/- 2°C], Mixes were then whipped at the highest speed, After one minute, the beater was adjusted to the lowest speed during which hot [100°C] vitreous sugar syrup [VSS] containing 64,5% sucrose and 0,03% Na citrate was slowly added at the rate of 250g to 100g whipped mix followed by adding 0,01g vanilla powder. Foaming power [FP] and foam stability [FS] of whipped mixes [without VSS] were determined at room temp. Final product [meringue] was examined for the organoleptic properties as well as leakage and slipping rated during cold storage [5°C] Higher levels of replacements were associated with increase in [FP] and decrease in [FS] of mixes. While the presence of UF-WPC led also to a relative decrease in the leakage property, the slipping property increased. Replacements over 25% and 75% of UF-WPC alkalized with Na[2]CO[3] and NaHCO[3] respectively were associated with a bitter chalky flavour. The study showed the value of using UF-WPC in the confectionery industry. Whey proteins are available for making food foams, especially when some of the SS-groups are reduced and hydrophobic sites become accessible. Studies claim that, it may be difficult but not impossible, to prepare a substitute for ovomucin [the main protein component of egg white in foam forming and stabilization] from whey proteins [De Wit, 1985] The suitability or utility of when or its concentrates as a partial or total replacement of whole egg or egg white in various food products were reported by many authors [Lovachev et al., 1982, Mann, 1982 and Nakai and Licahn, 1985] Soft meringue, which is usually used as pie topping could be made by whipping the egg white alone and stabilizing the foam white hot vitreous sugar [Felt et al., 1956] Therefore the present study was aimed to use UFWPC in meringue manufacture as egg white substitute