Estimation of Serpa cheese ripening time using multiple linear regression (MLR) considering rheological, physical and chemical data

Abstract

Raw ewes' milk semi-soft cheeses (RESS-cheeses) are important products in Portugal and in several European regions. Creamy texture is an essential attribute of these cheeses, which results from structural properties that are not always well characterized. Here, the structural changes occurring during the ripening period of a traditional RESS-cheese, known as Serpa cheese, were analysed through small amplitude oscillatory shear (SAOS). Rheological data was complemented with other physical and chemical parameters, that were monitored during ripening, in order to estimate Serpa cheese ripening time using multiple linear regression (MLR). Mechanical spectra indicated a relatively strong structure, comparable to a gel, with a low dependence on frequency at the beginning of ripening and a weak structure, comparable to a concentrated suspension, with a crossing point (G''=G') at the left of the graphic and with both moduli highly dependent on frequency, at the end of ripening. Good correlations (P<0.05) were obtained between structural (hardness and storage modulus) and proteolysis indicators. Using a combination of chemical, colour and rheological parameters we were able to obtain a multiple linear regression (MLR) which allows the estimation of Serpa cheese ripening time with an estimation error of 1.7 d (adjusted R2=0.98, P<0.0001).

Bacterial Communities in Serpa Cheese by Culture Dependent Techniques, 16S rRNA Gene Sequencing and High‐throughput Sequencing Analysis

“…The cheese samples had a pH range between 4.95−5.49, with the highest values for industry V and A in spring season. These pH data are in concurrence with those reported for soft cheeses (Alvarenga, Silva, Garcia, & Sousa, ; Ordiales et al., ; Roseiro, Wilbey, & Barbosa, ). At 30 days of ripening, the moisture content of the cheeses ranged from 45.02 to 48.76% ( p < 0.05) for PDO industries and 39.10‐51.90% for non‐PDO registered industries, while the a w values were around 0.90 to 0.98.…”

“…Overall the results obtained in PDO registered industries agreed with the findings presented by Alvarenga et al. () in Serpa Portuguese cheese.…”

“…Significant differences in moisture and a w between samples from industry V (non-PDO registered) and the rest of the industries were observed. Overall the results obtained in PDO registered industries agreed with the findings presented by Alvarenga et al (2008) in Serpa Portuguese cheese.…”

Effect of hydrocolloids on low-fat chocolate fillings

“…Experimental data were subjected to one-way ANOVA (pairwise comparison of means with Scheffé test) in order to find differences in samples of the same type of chocolate but with different types (and amounts) of hydrocolloids. Data was analyzed using Statistica 6.0 (Statsoft, Tulsa, USA) (Alvarenga et al 2008). …”

Substitution of sodium chloride by potassium chloride in São João cheese of Pico Island

“…Instrumental texture profile analyses (TPA) was performed on a TAHDi texture analyzer (Stable Micro Systems, Godalming, UK) according to Alvarenga et al (2008Alvarenga et al ( , 2011 with some modifications. Cheeses from the second trial on 17th day of ripening were equilibrated at room temperature (20 ± 1°C) during 12 h. The consumers generally held the São João cheese in the refrigerator, but they eat the cheese at room temperature.…”