Experiments were designed to determine the effect of the chemical state of myoglobin and presence of ascorbate on the conversion of nitrite to nitrate. In model systems, nitrate was not formed when nitrite was incubated in the presence of either metmyoglobin or ascorbate. However, most of the added nitrite was converted to nitrate when both ascorbate and metmyoglobin were present. It is suggested that ascorbate reduces metmyoglobin to myoglobin, and then, the myoglobin is oxidized simultaneously with nitrite to form nitrate. In cured meat products, a detectable level of nitrate was formed in the absence of ascorbate, but in the presence of ascorbate the level of nitrate formed was greater. The explanation suggested was that endogenous reductants in meat could play the same role as ascorbate in model systems. Such endogenous reductants were responsible for more than half of the nitrate formation in meat products containing sodium ascorbate.

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A sound velocimeter was used to study the physical structure of aqueous solutions (0.0-1.20 molal) of five monosaccharides, fructose, galactose, glucose, mannose and xylose. Over most of the temperature range employed (20-80°C) adiabatic compressibility of the solutions was the dominant factor in defining sound velocity through and structural rigidity of solution. Analysis of the data also indicated that differences in the solution rigidity of the various monosaccharides was attributable to structural differences among the sugars. At temperatures less than 30°C, where foods are often stored or consumed, fructose produces the most rigid structure followed in descending order by galactose, glucose, mannose and xylose.