Sweetness of α‐, β‐, and Equilibrium Lactose Relative to Sucrose

Abstract

The sweetness of 01-, p-, and equilibrium lactose, measured by a trained panel using paired comparison with standard reference solutions of sucrose of concentrations from 0.50-6.50%, ranged from 30-35% that of sucrose. The sweetness of p-lactose was 105-122% that of a-lactose. The predicted sweetness of lactose at mutarotation equilibrium, calculated from sweetness values for OL-and p-lactose and from the relative amounts present as determined by polarimetry, i.e., 38% 01 and 62% p, did not differ significantly from the experimentally determined sweetness value, indicating an absence of synergism for sweetness in mixtures of (Y-and p-lactose. Isosweet sucrose concentrations for three different concentrations of pand equilibrium lactose and two concentrations of ar-lactose are reported. INTRODUCTIONTHE POTENTIAL of a-lactose monohydrate in baking applications has been examined by Ash (1976), and limitations of this form of lactose were its low solubility and its low sweetness compared with sucrose. Plactose has much greater solubility compared with a-lactose monohydrate (Whittier, 1944), and Goldman and Short (1977) used & lactose to replace up to 25% of the sucrose in a high-ratio cake formulation without affecting size, tenderness, or sweetness. Sugars are important food ingredients, and the relative sweetness of sugars has been of great interest to food scientists. Few studies have been made on the relative sweetness of (Y-and Plactose, although differences in sweetness of anomeric forms of several sugars have long been recognized (Cameron, 1947; Pangborn and Gee, 1961; Pangbom and Chrisp, 1966). Pangbom and Gee (1961) compared the sweetness of (Y-and &lactose, and the sweetness of each of these forms relative to lactose solution which had reached mutarotation equilibrium. They found plactose to be sweeter than a-lactose at superthreshold concentrations (5% and 7%) but did not measure the magnitude of the relative sweetness. Dahlberg and Penczek (194 1) measured the sweetness' of /3-lactose (6-33%) relative to sucrose (2-20%), but did not test (Y-or equilibrium lactose. In the present study, the sweetness of CX-, fl-, and equilibrium lactose relative to sucrose was measured. In addition to establishing the sweetness of fl-lactose relative to (ILlactose, this study sought to determine from the sweetness of equilibrium lactose whether synergism could be demonstrated for a mixture of lactose anomers as has been shown for mixtures of glucose and fructose, and of glucose and sucrose (Stone and Oliver, 1969).

Anomeric discrimination and rapid analysis of underivatized lactose, maltose, and sucrose in vegetable matrices by U‐HPLC–ESI‐MS/MS using porous graphitic carbon

“…5C). Our measured equilibrium compositions at 20 °C for lactose and maltose were, respectively, ca 61 and 62% of the β anomer, in good agreement with literature values of 57.3–62.3% for lactose and 61.9–63.9% for maltose 19, 23, 24…”

Quantification of sensory difference thresholds for fat and sweetness in dairy-based emulsions

“…Sucrose addition was varied to maintain a constant sugar concentration in the aqueous phase (further denoted as sugar concentration index) of 5%. The relative sweetness of lactose which was introduced through addition of reconstituted skim milk was considered as 0.33 (Parrish, Talley, & Phillips, 1981). Vanilla flavor concentration in the aqueous phase was set to 0.2%.…”

Functionality of Sugars in Foods and Health

“…Reducing sugars typically exist as a mixture of α and β anomers, as natural interconversion between open‐ and closed‐chain forms results in anomerization to an equilibrium mixture of α and β anomers within a few hours of solvation. Differences in sweetness have been found between the α‐ and β‐anomeric forms of several sugars, though only for lactose has the magnitude of that difference been explicitly quantified (Pangborn and Gee ; Steinhardt and others ; Parrish and others ; Sakaguchi and others ). Pangborn and Gee () found the α‐form of fructose, glucose, and galactose to be the sweeter anomer, whereas the β‐form of lactose was judged to be sweeter than α‐lactose (Parrish and others ).…”

“…Differences in sweetness have been found between the α‐ and β‐anomeric forms of several sugars, though only for lactose has the magnitude of that difference been explicitly quantified (Pangborn and Gee ; Steinhardt and others ; Parrish and others ; Sakaguchi and others ). Pangborn and Gee () found the α‐form of fructose, glucose, and galactose to be the sweeter anomer, whereas the β‐form of lactose was judged to be sweeter than α‐lactose (Parrish and others ). The differences in perceptibility of sweetness of α‐ and β‐anomers are generally small (on the order of 5% to 20%) and concentration‐dependent (increasing with concentration) (Pangborn and Gee ; Parrish and others ).…”

“…Pangborn and Gee () found the α‐form of fructose, glucose, and galactose to be the sweeter anomer, whereas the β‐form of lactose was judged to be sweeter than α‐lactose (Parrish and others ). The differences in perceptibility of sweetness of α‐ and β‐anomers are generally small (on the order of 5% to 20%) and concentration‐dependent (increasing with concentration) (Pangborn and Gee ; Parrish and others ). It is important to note, that although α‐ and β‐sugar anomers may differ in their degree of sweetness, d ‐ and l ‐isomers have the same degree of sweetness.…”