The effects of ingredients and water content on the rheological properties of batters and physical properties of crusts in fried foods

Abstract

This study investigated the effect of ingredients and flour/water ratio on the rheological properties of batter. Replacing part of the wheat flour present in a weak composition (W-pattern) batter with gluten yielded a higher protein concentration that renders a strong composition (S-pattern) batter. This study also tested the effects of adding HPMC to S-pattern (SH-pattern) batter and crisping agents to W-pattern (WC-pattern) batter. The S- and SH-pattern batter exhibited Bingham-pseudoplastic fluid properties in a temperature range of 5–35 °C. W-pattern batters with a flour/water ratio of 1/1.5 and WC-pattern batters with flour/water ratio of 1/1 exhibited pseudoplastic fluid properties. Adding HPMC increased the fluid consistency index ( b) of batter, revealing a higher viscosity and diminished fluidity. This batter showed a higher thermal solidification temperature and increased shear modulus ( G′, G″), complex viscosity and further raised the batter pick-up. The addition of crisping agents to W-pattern batter shifted solidification temperature to a lower range. In fried mackerel nuggets, the S- and SH-pattern crusts exhibited a texture that was firm and brittle, while W- and WC-pattern crusts exhibited a texture that was significantly more crisp.