Dextran modulates physical properties of rennet‐induced milk gels

Abstract

Summary Physical properties of rennet‐induced milk gels as core intermediates of cheese production are mainly affected by milk composition, type and amount of coagulation enzyme and starter culture activity. We investigated model systems of reconstituted milk and dextran, which triggers effects on milk gels similar to exopolysaccharides from lactic acid bacteria. Furthermore, clotting activity (0.02 or 0.04 IMCU mL−1) and milk pH adjusted prior to renneting (6.5–5.7) were studied. A lower pH at renneting resulted in an earlier gelation onset, a higher gelation velocity and gel stiffness. The addition of dextran stabilised the gels especially at higher pH, and microstructural analysis revealed larger, more interconnected protein aggregates. However, at pH 5.7, a reverse effect was observed, indicating a destabilisation of the casein network. The current study indicates that altering milk pH and addition of polysaccharides gives the potential to change textural properties of cheese by affecting rennet‐induced gelation.

Acid-Induced Gelation of Enzymatically and Nonenzymatically Cross-Linked Caseins—Texture Properties, and Microstructural Insights

“…Haralick’s texture parameters derive from the sum of all GLCM elements, which are weighted by either the value of the element (type 1) or its spatial position (type 2). The type-1 features angular second moment (ASM; eq ) and Shannon entropy (SE; eq ) as well as the type-2 feature inverse difference moment (IDM; eq ), most recently utilized for texture evaluation of micrographs of different types of casein gels, − were computed for d = 1 and φ = 0 and 90° as follows, using the ImageJ plugin ‘Texture Analyzer’ (version 0.4): …”

Influence of dextrans on the textural, rheological, and microstructural properties of acid-induced faba bean protein gels

“…WHC is another important gel quality parameter, and it signifies the gel’s capacity to immobilize water through capillary force. Moreover, WHC is also associated with the gel’s matrix structure ( Mende et al, 2020 ), and a low WHC generally indicates low textural stability ( Zheng et al, 2019 , Zheng et al, 2019 ). As shown in Table 2 , the addition of DXs with different macromolecular properties had different effects on the WHC of FPI gels.…”

Investigation on exopolysaccharide production by Lacticaseibacillus rhamnosus P14 isolated from Moroccan raw cow's milk

“…Further studies were conducted to determine the relationship between EPS structure and their different function in different matrices. It is worth mentioning that EPS has been reported as a thickening, gelling, stabilizing, and emulsifying agent to improve the rheological properties of fermented milk (Mende et al., 2019; Silva et al., 2019). Moreover, EPS have also demonstrated some biological and pharmacological properties such as antioxidant (Wang et al., 2019), antitumor (Wei et al., 2019), immune‐modulating (Garcia‐Castillo et al., 2020), and other activities (Saadat et al., 2019), since they are capable of interacting with the immune system.…”