For food-sugar electroanalysis, it is important to have a chemically meaningful value of the concentration, not just an elevated electrode current. This paper addresses the research question on the viability of developing a mode-specific rule for food-sugar readings by NiFe alloy nanowires using chronoamperometry on five different reducing sugars and seven food samples. The analytical system contains glucose, fructose, galactose, lactose, and maltose calibration information; direct reducing-sugar measurements for peach juice, honey, diet coke, milk, isotonic solution, and apple; and total-sugar measurements for peach juice, coke, diet coke, and apple, including conversion from non-reducing sugar. Calculations include calibration window usefulness, carbon-normalised response density, cross-family concentration difference, recovery agreement, replicate dispersion, and liquid sample dilution position. Glucose had the highest usefulness among single sugars, whereas fructose and galactose had an informative monosaccharide family and lactose/maltose had a less responsive disaccharide family. Monosaccharide mean sensitivity was 0.6427 μA μM−1 cm−2 and disaccharide mean sensitivity was 0.3555 μA μM−1 cm−2, with a raw slope ratio of 1.81. The use of carbon-normalised response density amplified the class difference to 3.62. This demonstrates that the disaccharide response is not proportional to the molecule size. Cross-family slope transfer underestimates disaccharides by 44.7% or overestimates monosaccharides by 80.8%. The average recovery of direct reducing-sugar measurements was 98.05%, the average recovery of total-sugar measurements was 99.11%, and non-zero replicate dispersion was lower in direct measurements than in total-sugar measurements. Liquid foods needed approximately 854–4225-fold dilution to bring the aliquot close to 0.18 mM within the common first calibration window. The research question is answered positively: NiFe nanowire food-sugar readings are best expressed by mode chemistry, with class-specific calibration, interior window dilution, and recovery-dispersion interpretation mentioned together.