| CLrate, Chilling Rate |
the Newtonian cooling rate, that is, the rate at which the solution experiences a decrease in temperature without ice nucleation and growth. |
| [DEXTR] |
the initial concentration (% by weight) of the dextrose in the ICM. |
| [HYD] |
the initial concentration (% by weight) of all hydrocolloids in the ICM (i.e., maltodextrin, inulin, sucrose esters, carrageenan, Tara seed flour and carboxymethylcellulose arising from the multicomponent basis used in the formulation of the ice cream mixtures). |
| [FAT] |
the initial concentration of fat in the ICM. |
| FP, Freezing Point (°C) |
the equilibrium freezing temperature experienced by the WBMS, at which the ice crystal starts to growth with a steady-state kinetics (i.e., without changes in temperature): it was determined as the highest temperature after the unique supercooling event as registered by the lowest experimental temperature. |
| FPD, Freezing Point Depression (°C) |
the fall of the equilibrium freezing temperature below 0 °C due to the presence of colligative solutes. |
| FPt, Theoretical Freezing Point |
the theoretical equilibrium freezing temperature that the WBMS can virtually experience on cooling if they would behave as a pure sucrose solution having an equivalent concentration of sucrose. |
|
|
the maximum rate (1/min) of the water crystallization (or equivalently, the maximum Growth Rate of the ice crystals) that takes place during batch ice cream production. |
| Gpz’ |
first derivative function of the re-parameterized Gompertz’s model. |
| Gpz,” |
second derivative function of the re-parameterized Gompertz’s model. |
| Gpz’’’ |
third derivative function of the re-parameterized Gompertz’s model. |
| GRtime
|
the freezing time corresponding to GRmax.
|
| GRT
|
the freezing temperature corresponding to GRmax.
|
| HNT, Heterogeneous Nucleation Time |
the time length (min) required to form stable ice nuclei through one (as experienced by the WBMS) or more than one (as experienced by the MBMS and ICM) supercooling events before to reach respectively FP or IFP. |
| HSC, High Sugar Content |
ice cream mixture prepared with the highest content of the colligative sugars. |
| ICM |
Ice Cream Mixture. |
| IFP, Initial Freezing Point (°C) |
the first equilibrium freezing temperature experienced during cooling by the investigated MBMS and ICM (it was determined as the highest temperature after the first supercooling event as registered on the experimental cooling curve). |
| IFPeff, Effective Initial Freezing Point (°C) |
the equilibrium freezing temperature at which the water crystallization kinetics is at its acceleration point, after the heterogeneous nucleation step and where the ice starts to accumulate significantly and extensively in the ICM (it was estimated by using the re-parameterized Gompertz’ model). |
| IFPt, Theoretical Freezing Point |
the theorical equilibrium freezing temperature that the investigated MBMS and ICM can experience virtually if they would behave on cooling as a pure sucrose solution having an equivalent concentration of sucrose. |
| ILP |
Interaction Linear Plot obtained by linear regression analysis of the experimental data corresponding to the inverse values of the freezing point depression (x-data) and the ratio between Mw/Ms (y-data). |
| IS, Initial Supercooling (°C) |
the maximum temperature depression below 0 °C experienced on cooling by the investigated MBMS and ICM at the point corresponding to the first ice nuclei formation. |
| LAGTIME
|
the time at which melting of the ice cream accelerates. |
| LSC, Low Sugar Content |
ice cream mixture prepared with the lowest total sugar content. |
| MBMS |
Milk-based model systems (i.e., MSUCR, MSUCR + MDEXTR, MDEXTR, MSORB). |
| m0
|
the total mass of the ice cream. |
| mD
|
the mass of the drip loss during melting of the ice cream. |
|
|
the maximum rate (1/min) of the ice cream melting. |
| Ms |
the concentration of the sucrose equivalents (expressed as g/100 of water) corresponding to all the colligative solutes. |
| MSC, MSC1, MSC2, MSC3 and MSC4 |
Medium Sugar Content: ice cream mixtures prepared with the same intermediate total sugar content but varying the concentration of the individual sugar added as sweeteners, that is, sucrose, dextrose and sorbitol. |
| MSNF, Milk Solids Non-Fat |
they include all solids in milk other than fat in the ICM. |
| MSUCR, MDEXT, MSORB |
milk-based model systems prepared by adding 300 g of sucrose or dextrose or sorbitol to 1000 g of whole milk, respectively. |
| MSUCR + MDEXTR |
milk-based model systems prepared by adding 150 g of sucrose and 150 g of dextrose to 1000 g of whole milk. |
| Mw |
the mass fraction (% by weight) of the initial water of the ICM. |
| n |
the number of time-temperature data registered by the PT100 probe inside the SSHE. |
| NUR, Nucleation Rate (°C/min) |
the rate of formation of unstable ice nuclei in the unique supercooling domain (as experienced by the WBMS) or in the first supercooling domain (as experienced by the MBMS and ICM). |
| S, Supercooling (°C) |
the maximum temperature depression below 0 °C required by the water to begin crystallization in the WBMS. |
| [SE] |
the concentration (% by weight) of the sucrose equivalents as calculated by summing the individual contribute of all colligative solutes present in a given solution, provided that the it would behave as a pure sucrose solution (“sucrose equivalency” was derived for a comparison of the mean molecular weights for each colligative solute with that of the sucrose). |
| [SORB] |
the initial concentration (% by weight) of the sorbitol in the ICM. |
| SSHE |
Scraped-Surface Heat Exchanger used for batch ice cream production. |
| [SUCR] |
the concentration (% by weight) of the sucrose. |
|
|
the experimental temperature (°C) at a given time (t) registered by the PT100 inside the SSHE. |
| TCL (t) |
the theoretical temperature (°C) at a given time (t), that either the MBMS and the ICM would experience under a pure Newtonian cooling process, that is, without experience ice nucleation and ice growth. |
| Texit
|
the temperature (°C) at which the ice cream exits from the SSHE. |
| TP1 |
First target point: the temperature at which the formation of unstable clusters of ice nuclei begins and the cooling curve starts to deviate from its linear trend experienced during the chilling step of cooling: it was estimated by determining the minimum significant difference between the experimental temperature and the theoretical temperature TCL (t). |
| TS, Total Solids |
the total mass fraction (% by weight) that includes all solids that are present in the WBMS, MBMS and ICM. |
| tTexit
|
the time (min) corresponding to Texit.
|
| tTwhipp
|
the time (min) corresponding to Twhipp.
|
| Twe
|
the temperature (°C) corresponding to the intermediate time between Twhipp and Texit.
|
| Twhipp
|
the temperature (°C) at which the water crystallization kinetics is at its decelerating point and air incorporation starts to dominate on the ice growth (it was estimated by using the re-parameterized Gompertz’ model). |
| WBMS |
Water-based model systems (i.e., WSUCR, WSUCR + WSORB, WDEXTR, WSORB) |
|
, Freezable Water Fraction (%) |
the time-dependent changes in mass fraction (% by weight) of the water initially present in the ICM and that can be virtually converted in the ice during freezing under batch SSHE conditions, as estimated by using the re-parameterized Gompertz’s function. |
|
, Experimental Freezable Water Fraction |
the time-dependent changes in mass fraction (% by weight) of the water initially present in the ICM and that can be virtually converted in the ice during freezing under batch SSHE conditions, as estimated by coupling the experimental time-temperature data to the reverse relationship between the freezing point depression values tabulated for pure sucrose solutions with different sucrose concentrations and the corresponding mass fraction of the initial water that can be converted in the ice. |
|
|
the upper asymptotic level of . |
| Wice cream
|
the weight of a standard volume of the just extruded ice cream (used for overrun measurements). |
| Wmixture
|
the weight of the ice cream mixture after aging corresponding to the same volume of Wice cream (used for overrun measurements). |
| WSUCR, WDEXT, WSORB |
water-based model systems prepared by adding 300 g of sucrose or dextrose or sorbitol to 1000 g of water, respectively. |
| WSUCR + WSORB |
water-based model systems prepared by adding 150 g of sucrose and 150 g of sorbitol to 1000 g of water. |
| ∆FP |
the difference between the FPt and FP. |