Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Food Science & Technology, Cell wall material, Pectin depletion, High-pressure homogenization, Cryogenic ball milling, Rheology, Water binding capacity, Microscopy, Particle size distribution, RHEOLOGICAL PROPERTIES, VISCOELASTIC PROPERTIES, PARTICLE DISPERSIONS, FIBER, CARROT, SUSPENSIONS, PRODUCTS, FRACTION, POWDER, APPLE, Cell Wall, Solanum lycopersicum, Pectins, Suspensions, Water, 1134619N|1134621N#54334938, 1252221N#55741512, 0904 Chemical Engineering, 0908 Food Sciences, 1111 Nutrition and Dietetics, Food Science, 3006 Food sciences, 3210 Nutrition and dietetics, 4004 Chemical engineering

Abstract:

In the current study, the effect of different particle size reduction techniques, namely high-pressure homogenization (HPH) and cryogenic ball milling (CBM), on the microstructural and texturizing properties of the tomato acid-unextractable fraction (AcUF) in suspension was studied. Partial pectin depletion was performed by nitric acid pectin extraction on the alcohol-insoluble residue. In the absence of the aforementioned mechanical treatments, the partially pectin-depleted material, i.e., the AcUF, showed a cellular morphology and a high texturizing potential. By short-time CBM in dry-state, the AcUF was extensively fractured and clumped, resulting in a collapsed structure with negligible texturizing potential and low water binding capacity. In contrast, HPH could disrupt the cell wall network (destroying the cellular morphology) resulting in a continuum of interacting material having very similar texturizing potential and a slightly higher water binding capacity than the AcUF before HPH. Furthermore, the potential of HPH to (re)functionalize the collapsed cryo-ball milled AcUF by its shear-induced disruption was shown. Indeed, the debris-like cell wall remnants could to some extent be reopened by HPH, which resulted in a partial recovery of the original texturizing potential and an improved water binding capacity. However, the potential of HPH at 20 MPa to revert the detrimental effect of CBM decreased with increasing CBM treatment time.