${\mathrm{n}}_0$, ${\mathsf{\alpha }}_{\mathrm{i}}$	parameters in viscosity model
$\mathrm{A}$, $\mathrm{B}$	coefficients depending on screw geometry for an equation expressing volumetric flow rate through a screw channel
AF4	asymmetrical flow field flow fractionation
CB	cacao-based extruded breakfast cereals
$\mathrm{Cp}$	specific heat of hydrated molten starch (J kg−1·°C−1)
${\mathrm{Cp}}_{\mathrm{s}}$	specific heat of anhydrous starch (J·kg−1·°C−1)
${\mathrm{Cp}}_{\mathrm{w}}$	specific heat of water (J·kg−1·°C−1)
D	die or screw diameter (mm)
DSC	differential scanning calorimetry
DTE	dithioerythritol
$\mathrm{E}$	activation energy (J·mol−1)
${\mathrm{E}}_{\mathrm{v}}$	specific energy dissipated by molten starch (kJ·kg−1)
${\mathrm{E}}_{\mathrm{cd}}$	specific energy supplied by conduction from the surfaces of the barrels and screws (kJ·kg−1)
FF	fava bean flour
FSC	fava bean starch concentrate
HB	malt-based extruded breakfast cereals
Insol	total amount of in-extractable proteins in SDS and DTE (%)
$\mathrm{K}$	flow consistency index (Pa·sn)
${\mathrm{K}}_0$	consistency at reference temperature ${\mathrm{T}}_0$ and reference moisture content ${\mathrm{MC}}_0$ (Pa sn)
$\mathrm{k}$	thermal conductivity of hydrated starch (W·m−1 K−1)
${\mathrm{k}}_{\mathrm{s}}$	thermal conductivity of anhydrous starch (W·m−1 K−1)
${\mathrm{k}}_{\mathrm{w}}$	thermal conductivity of water (W·m−1 K−1)
L	die or screw length (mm)
L/D	length to diameter ratio (dimensionless)
Maize A	high amylose maize starch (Eurylon 7)
Maize B	blend of Euroylon 7 and Waxilys 100 with a ratio 2 to 1
Maize C	blend of Euroylon 7 and Waxilys 100 with a ratio 1 to 1
Maize D	waxy maize starch (Waxilys 100)
MALLS	multi-angle laser light scattering
MC	moisture content (% in wet basis)
${\mathrm{MC}}_0$	reference moisture content (%)
$\mathrm{n}$	flow behavior index (dimensionless)
N	screw speed (rpm)
NC	cell density (cm−3)
Ng	starch granule number per unit area (mm−2)
Nu	Nusselt number (dimensionless)
P_mes	pressure, measured at die entrance of extruder (Pa)
P_com	computed pressure at die entrance (Pa)
PF	pea flour
Potato A	potato starch studied in Della Valle et al. [31]
Potato B	potato starch studied in Logié et al. [32]
PS	pea starch
$\mathrm{R}$	gas constant (J·mol−1·K−1)
SDS	sodium dodecyl sulphate
SE-HPLC	size-exclusion high-performance liquid chromatography
RM	starch residual molecular mass (%)
Q	total feed flow rate (kg·h−1)
${\mathrm{Q}}_{\mathrm{v}}$	volumetric flow rate in a screw channel (m3·s−1)
Q/N	filling ratio of extruder
SEI	sectional expansion index
SME	specific mechanical energy (kJ·kg−1)
SME_mes	predicted SME (kJ·kg−1)
SME_com	specific mechanical energy, retrieved experimentally (kJ·kg−1)
T	melt temperature (°C)
${\mathrm{T}}_{\mathrm{a}}$	absolute temperature (K)
Tb	imposed barrel temperature (°C)
Td	imposed die temperature (°C)
Tm	melting temperature (°C)
${\mathrm{T}}_0$	reference temperature (°C)
T_mes	melt temperature, measured at die exit (°C)
T_com	predicted melt temperature at die exit (°C)
$\mathrm{V}$	free volume of a screw element (m3)
w.b.	wet basis
WF	refined wheat flour
WF-LB	refined wheat flour containing low content of wheat bran (12.6%)
WF-HB	refined wheat flour containing high content of wheat bran (24.4%)
$\dot{\mathrm{W}}$	power dissipated in the volume V of a screw element (Watt)
WSIstarch	water solubility index of starch (in kg/kg dry starch in flour or %)
${\mathrm{X}}_{\mathrm{w}}$	mass fraction of water (kg·kg−1)
${\mathrm{X}}_{\mathrm{s}}$	mass fraction of starch (kg·kg−1)
$\mathsf{\alpha }$	water plasticization coefficient (dimensionless)
$\mathsf{\beta }$	thermomechanical history coefficient (kg·kJ−1)
$\mathsf{\eta }$	melt viscosity (Pa·s)
η_com	predicted melt viscosity at die exit (Pa·s)
$\dot{\mathsf{\gamma }}$	local or true shear rate (s−1)
$\mathsf{\Delta }\mathrm{P}/\mathsf{\Delta }\mathsf{\theta }$	pressure variation along angular screw section (Pa)
$\mathsf{\Delta }\mathrm{T}$	temperature change in a screw section (°C)
ΔVis	drop of intrinsic viscosity (%)
$\mathsf{\Omega }$	screw speed (rad·s−1)
$\mathsf{\rho }$	density of snack or molten feed (kg·m−3)
${\mathsf{\rho }}_{\mathrm{s}}$	density of anhydrous starch or flour (kg·m−3)
${\mathsf{\rho }}_{\mathrm{w}}$	density of water (kg·m−3)
$\mathsf{\nu }$	water volume fraction