General Analytical Schemes for the Characterization of Pectin-Based Edible Gelled Systems

Table 3

Typical examples of experimental set up and recorded parameters based on small deformation rheological measurements (oscillatory tests) for pectin-based gels.

Sample ingredients	Experimental setup	Recorded parameters	References
HMP and fructose	Carri-med rheometer (Valley View, OH); geometry: cone and plate (4 cm diameter; 2° cone angle); strain: 3%; frequency: 1 Hz; duration: 2 h; temperature sweep: 50–10°C; frequency sweep: 0.01–1 Hz; temperatures: 50, 40, 30, 20, 15, and 10°C	𝐺^; 𝐺^; η *; tan δ; SDR	Rao and Cooley [10]
ALMP, Sucrose, and grape juice	Stress-controlled rheometer (Bohlin CS, ref. GTM-CS-V1); geometry: cylindrical concentric with a double gap (30 mL capacity); strain: 2%; frequency sweep: 0.005–2 Hz,; temperatures: 65, 50, 35, 20, and 10°C; speed: 0.5°C/min	𝐺^; 𝐺^; tan δ	Sousa et al. [14]
Pectin, sucrose, and calcium	Stress-controlled rheometer CSL-100 (TA Instruments, Surrey, UK); geometry: cone and plate (4 cm diameter; 1° cone angle; 55 μm truncation); strain: 1.5%; frequency: 0.1–10 Hz, Temperature sweep: 90–20°C; speed: 3°C/min, frequency: 1 Hz	𝐺^; 𝐺^; η *; tan δ	Norziah et al. [16]
LMP (olive pectic extract) and CaCl2	CVO HR 120 rheometer (Bohlin Instruments); geometry: cone and plate (40 mm diameter; 4° cone angle; 150 μm gap); strain: 1%; frequency:1 Hz; Time sweep: 20 h; temperature: 20°C; Frequency sweep: 0.005–5 Hz	𝐺^; 𝐺^	Cardoso et al. [17]
LMP, ALMP, CaCl2, and GDL	Strain-controlled rheometer (ARES, Rheometric Scientific); geometry: cone and plane geometry (50 mm diameter; 2.3° cone angle); or a couette geometry (32 mm inner radius; 34 mm outer radius); atress-controlled rheometer (AR1000, TA Instruments); geometry: cone and plane (40 mm diameter; 1° cone angle); frequency: 1 Hz; temperature sweep: 80–20 or 5°C; speed: 30°C/min	𝐺^; 𝐺^; Tg	Lootens et al. [18]
ALMP, Sodium caseinate solution, CaCl2·2H2O and GDL	Bohlin rheometer (CS50, CVO or CVO-R); stress-controlled geometry: concentric cylinder C25 measurement cell; strain: 0.5%; frequency: 1 Hz; duration: 8 h; temperature: 25°C	𝐺^; 𝐺^	Matia-Merino et al. [8]
HMP, sorbitol, fructose, glucose, sucrose, xylitol, glycerol or ethane-1,2-diol and trisodium citrate	A sensitive prototype rheometer designed and constructed by R. K. Richardson (Cranfield University, UK); geometry: highly truncated cone and plate (50 mm diameter; 0.05 rad cone angle; 1 mm gap); strain: 0.5%; frequency: 1 rad/s; temperature sweep: 95–5, 5–90°C, and 90–5°C; speed: 1°C/min; frequency sweep: 0.1–100 Hz	𝐺^; 𝐺^	Tsoga et al. [19]
LMP, ALMP, CaCl2, and GDL	Strain-controlled rheometer (ARES, Rheometric Scientific); geometry: plane-plane (50 mm diameter; 1 mm gap); or a stress-controlled rheometer (AR1000, TA Instruments); geometry: cone-plane (60 mm diameter; 1° cone angle); frequency: 1 Hz; temperature sweep: 80–5°C	𝐺^; 𝐺^; Tg	Capel et al. [20]
HMP, LMP, CaCl2·2H2O, citrate buffer (pH: 3.5), and different sucrose concentrations	Stresstech rheometer (Reologica Instruments, Lund, Sweden); strain-controlled; geometry: cup and bob; strain: 0.002; frequency: 1 Hz; temperature: 20°C, time sweep: 3 and 16 h; frequency sweep (16 h after gel preparation): 0.01–10 Hz	𝐺^; 𝐺^	Löfgren and Hermansson [21]
ALMP and Carrageenan	Stresstech rheometer (Reologica AB, Lund, Sweden); geometry: plate-serrated plate (25 mm diameter); stress sweep from 0.01 until critical stress at a frequency of 1 Hz	𝐺^; 𝐺^; η *; tan δ	Arltoft et al. [2]
LMP (from “nopal” cactus pads) and CaCl2	Rheometrics (fluids spectrometer RFS II, piscattaway, NJ, USA); geometry: cone and plate (0.5 cm diameter; 0.04 rad cone angle); strain: 5%; frequency sweep: 1–21.5 rad/s; temperature sweeps: 85–5 and 60–5°C; Speed: 1°C/min	𝐺^; 𝐺^; η *; tan δ	Cárdenas et al. [22]
HMP, CaCl2, water, and enzyme solution	CarriMed CSL-100 rheometer, geometry: cone and plate (6 cm diameter; 2° cone angle),; Strain: 1%; frequency: 1 Hz; duration: 160 min; temperature sweep: 30–70°C; speed: 1°C/min	𝐺^; 𝐺^; η *	O’Brien et al. [23]
Pectin (from buttercup squash fruit) and sugar	Physica UDS 200 rheometer; geometry: cup and bob (17 mL total volume); strain: 1%; frequency sweep: 0.01–10 Hz; temperature sweeps: 90–20, 20–90°C; speed: 1°C/min; frequency: 1 Hz	𝐺^; 𝐺^	O’Donoghue and Somerfield [24]
Mucin and pectin	Paar Physica MCR 301 rheometer (Anton paar GmbH, Austria); geometry: parallel plate (0.05 mm gap; CP50-1) or a concentric cylinder (DG26.7); measuring system; frequency sweep: 100–0.1 Hz; temperature: 37°C	𝐺^; 𝐺^; tan δ	Sriamornsak and Wattanakorn [25]
Pectins with different DM and calcium	Rotational rheometer (ARES, TA Instruments, USA); strain-controlled; geometry: parallel plates (50 mm diameter; 1 mm gap); frequency: 10 rad/s; time sweep: 8 h; frequency sweep: 100–0.1 rad/s; temperature: 25°C	𝐺^; 𝐺^	Fraeye et al. [9]
LMP and calcium	Rotational controlled stress rheometer AR 2000 (TA Instruments); geometry: cone-plate (2 cm diameter; 4° cone angle; 53 μm gap); time sweep: 8 h, frequency: 1 rad/s; strain: 3%; Frequency sweep: 0.01–100 rad/s	𝐺^; 𝐺^	Gigli et al. [12]
LMP, HMP, sugar, CaCl2·2H2O, citrate buffer (pH: 3.5)	Stresstech rheometer (Reologica Instruments, Sweden); strain-controlled; geometry: Cup and bob (volume: 25 mL); sample volume: 15.9 mL; strain: 0.002; frequency: 1 Hz; time sweep: every 20 s for 500–600 sweeps	𝐺^; 𝐺^; tan δ	Holm et al. [3]
ALMP, HMP, inulin, Sorbitol, and CaCl2·2H2O	Paar Physica MCR 300 rheometer (Anton Paar GmbH, Austria); geometry: parallel plates (50 mm diameter; 1 mm gap); and cone and plate (50 mm diameter; 2° cone angle; 0.05 mm gap); strain: 1%; frequency sweep: 0.1–100 Hz; temperature sweep: 90–5°C; speed: 2°C/min	𝐺^; 𝐺^; 𝐺^∗; η *; tan δ	Haghighi et al. [26]

HMP: high methoxyl pectin; LMP: low methoxyl pectin; ALMP: amidated low methoxyl pectin; GDL: glucono-delta-lactone; DM: degree of methoxylation; 𝐺^: storage modulus; 𝐺^: loss modulus; η*: complex viscosity; tan δ: loss tangent; 𝐺^∗: complex modulus; SDR: structure development rate; Tg: gel temperature.