The role of sodium in the salty taste of permeate.

Journal of dairy science (2014-07-16)
K M Frankowski, R E Miracle, M A Drake
ABSTRACT

Many food companies are trying to limit the amount of sodium in their products. Permeate, the liquid remaining after whey or milk is ultrafiltered, has been suggested as a salt substitute. The objective of this study was to determine the sensory and compositional properties of permeates and to determine if elements other than sodium contribute to the salty taste of permeate. Eighteen whey (n=14) and reduced-lactose (n=4) permeates were obtained in duplicate from commercial facilities. Proximate analyses, specific mineral content, and nonprotein nitrogen were determined. Organic acids and nucleotides were extracted followed by HPLC. Aromatic volatiles were evaluated by gas chromatography-mass spectrometry. Descriptive analysis of permeates and model solutions was conducted using a trained sensory panel. Whey permeates were characterized by cooked/milky and brothy flavors, sweet taste, and low salty taste. Permeates with lactose removed were distinctly salty. The organic acids with the highest concentration in permeates were lactic and citric acids. Volatiles included aldehydes, sulfur-containing compounds, and diacetyl. Sensory tests with sodium chloride solutions confirmed that the salty taste of reduced-lactose permeates was not solely due to the sodium present. Permeate models were created with NaCl, KCl, lactic acid, citric acid, hippuric acid, uric acid, orotic acid, and urea; in addition to NaCl, KCl, lactic acid, and orotic acid were contributors to the salty taste.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Potassium phosphate dibasic, ACS reagent, ≥98%
Sigma-Aldrich
Potassium carbonate, ACS reagent, ≥99.0%
Sigma-Aldrich
Tetrabutylammonium hydrogensulfate, 97%
Sigma-Aldrich
Potassium carbonate, 99.995% trace metals basis
Sigma-Aldrich
Potassium phosphate dibasic, reagent grade, ≥98.0%
Sigma-Aldrich
Tetrabutylammonium bisulfate, puriss., ≥99.0% (T)
Sigma-Aldrich
Divinylbenzene, technical grade, 80%
Sigma-Aldrich
Lactose, tested according to Ph. Eur.
Sigma-Aldrich
Potassium carbonate, anhydrous, free-flowing, Redi-Dri, ACS reagent, ≥99%
Supelco
Tetrabutylammonium bisulfate, suitable for ion pair chromatography, LiChropur, ≥99.0%
Sigma-Aldrich
Potassium carbonate, reagent grade, ≥98%, powder, −325 mesh
Sigma-Aldrich
Potassium phosphate dibasic, anhydrous, for luminescence, for molecular biology, BioUltra, ≥99.0% (T)
Sigma-Aldrich
Potassium phosphate dibasic, meets USP testing specifications
Sigma-Aldrich
Potassium phosphate dibasic solution, 1.0 M
Sigma-Aldrich
Potassium carbonate, puriss. p.a., ACS reagent, anhydrous, ≥99.0% (T)
Sigma-Aldrich
Potassium carbonate, ReagentPlus®, 99%
Sigma-Aldrich
Potassium carbonate, BioXtra, ≥99.0%
Sigma-Aldrich
Potassium carbonate, anhydrous, powder, 99.99% trace metals basis
Sigma-Aldrich
Divinylbenzene, technical grade, 55%
Sigma-Aldrich
Potassium phosphate dibasic, puriss. p.a., ACS reagent, anhydrous, ≥99.0% (T)
Sigma-Aldrich
Potassium carbonate, anhydrous, free-flowing, −325 mesh, Redi-Dri, reagent grade, ≥98%
Sigma-Aldrich
Tetrabutylammonium hydrogensulfate, anhydrous, free-flowing, Redi-Dri, 97%
Supelco
Tetrabutylammonium bisulfate solution, suitable for ion pair chromatography, LiChropur, concentrate, ampule
Sigma-Aldrich
Potassium carbonate, meets USP testing specifications
Sigma-Aldrich
2-Methyl-3-heptanone, 99%
Sigma-Aldrich
Potassium phosphate dibasic, 99.95% trace metals basis
Sigma-Aldrich
Potassium carbonate, anhydrous, free-flowing, Redi-Dri, ReagentPlus®, 99%
Sigma-Aldrich
Potassium carbonate, BioUltra, anhydrous, ≥99.0% (T)
Sigma-Aldrich
Potassium carbonate, puriss., meets analytical specification of Ph. Helv., anhydrous, granulated, 99-101% (calc. to the dried substance)
Sigma-Aldrich
Tetrabutylammonium bisulfate solution, ~55% in H2O