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The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. To evaluate the effect of NaCl content on microbiological, biochemical, physicochemical, and sensorial characteristics, Munster cheeses were prepared from pasteurized milk seeded with 3 yeasts (Kluyveromyces marxianus, Debaryomyces hansenii , and Geotrichum candidum) and 5 ripening bacteria (Arthrobacter arilaitensis, Brevibacterium aurantiacum, Corynebacterium casei, Hafnia alvei , and Staphylococcus equorum). Experiments were performed in triplicate under 1.0%, 1.7%, and 2.4% NaCl levels in cheese. Ripening (d 2–27) was carried out at 12°C and 96% relative humidity. These kinetics were both reproducible and repeatable at a 99% confidence level. For each microbial, biochemical, and physicochemical parameter, 2 kinetic descriptors (the maximal or minimal rate and its occurrence time) were defined. On d 2, the physicochemical variables (water activity, dry matter, and water content) were strongly dependent on the salting level. From d 2 to d 27, K. lactis was insensitive to salt, whereas D. hansenii was stimulated. Geotrichum candidum growth appeared very sensitive to salt in cheese: at 1.0% NaCl, G. candidum exhibited overgrowth, negatively affecting rind appearance, underrind consistency and thickness, and off-flavor flaws. A salt concentration of 2.4% induced death of G. candidum. A total of 4 bacteria (A. arilaitensis, B. aurantiacum, C. casei , and H. alvei) were moderately sensitive to salt, but S. equorum was insensitive to it. Salt level in cheese had a significant effect on carbon substrate consumption rates. The lactate consumption rate in 1.0% salted cheeses was approximately twice higher than under 2.4% NaCl. Data analysis of microorganism, biochemical, and physicochemical kinetics, as well as sensory analysis, showed that 1.7% NaCl was the best salt level in Munster-type cheeses to achieve an optimum balance between cheese characteristics, sensory qualities, and marketability. [ABSTRACT FROM AUTHOR]

Penicillium camemberti plays a major role in the flavor and appearance of Camembert-type cheeses. However, little is known about its mycelium growth kinetics during ripening. We monitored the growth of P. camemberti mycelium in Camembert-type cheeses using real-time PCR in 4 ripening runs, performed at 2 temperatures (8 and 16°C) and 2 relative humidities (88 and 98%). These findings were compared with P. camemberti quantification by spore concentration. During the first phase, the mycelium grew but no spores were produced, regardless of the ripening conditions. During the second phase, which began when lactose was depleted, the concentration of spores increased, especially in the cheeses ripened at 16°C. Sporulation was associated with a large decrease in the mycelial concentration in the cheeses ripened at 16°C and 98% relative humidity. It was hypothesized that lactose is the main energy source for the growth of P. camemberti mycelium at the beginning of ripening and that its depletion would trigger stress, resulting in sporulation. [ABSTRACT FROM AUTHOR]

Abstract: Portions of pressed, uncooked Saint-Nectaire cheese were packaged either under vacuum in low water-permeability film (LWP) or in air in film with medium gas and water permeabilities (MWP) or with high water permeability (HWP), then ripened for four weeks and evaluated for microbiological and biochemical properties and appearance. LWP totally eliminated cheese respiration and limited water loss. Consequently, the appearance of the cheese surface was totally modified: mycelia disappeared as a result of decreased yeasts, moulds and Gram + non-lactic acid bacteria, and the entire surface was covered with a red/orange smear. The two other films allowed significant respiratory activity without a decrease in moulds or yeasts. For cheese portions wrapped with HWP, mass loss, lactic acid consumption and proteolysis were the highest and although the appearance of the cheese surface did not change throughout the four weeks, considerable undesirable growth of the ripening flora was observed. [Copyright &y& Elsevier]

Abstract: The effect of ripening conditions (two temperatures, 9 °C and 13 °C, and two relative humidities 93% and 97%) on the growth of Listeria monocytogenes and other microbial populations was evaluated in the cores and rinds of uncooked pressed type cheeses prepared with pasteurised milk and inoculated either with Streptococcus thermophilus only or with an anti-listerial consortium. Regardless of temperature and relative humidity (RH), inhibition by the anti-listerial consortium was stronger in the cheese cores than in the rinds. Temperature had no significant effect on L. monocytogenes counts in cores or rinds. However, at the beginning of ripening in the consortium cheese, L. monocytogenes growth was more strongly inhibited at 13 °C than at 9 °C. Regardless of inoculation type and ripening temperature, counts of L. monocytogenes were significantly lower in the cores and rinds of cheeses ripened at 93% than at 97% RH. Lactobacilli counts were higher at 13 °C than at 9 °C and at 93% than at 97% RH. Lactobacilli can help to inhibit L. monocytogenes by catabolising galactose and producing lactate. Further investigations will be needed to evaluate the effect of ripening at 13 °C and 93% RH on the sensorial properties of cheese. [Copyright &y& Elsevier]

To produce a wide variety of cheeses, it is necessary to control the ripening process. To do that, artisanal goat cheeses were ripened to evaluate the effects of temperature (10 and 14°C) and relative humidity (RH; 88 and 98%) on (1) 16 physicochemical characteristics throughout ripening and (2) 19 sensory characteristics at the end of ripening (d 12). Whatever the ripening time, the physicochemical characteristics were strongly dependent on the daily productions, which affected the sensory perception of the cheeses. Both physicochemical and sensory characteristics were strongly reliant on RH, whereas only a few of the characteristics were influenced by temperature changes. On d 12, whatever the ripening temperature, an RH increase from 88% to 98% modified many cheese characteristics (core pH, lactate consumption, underrind thickening, dry matter content, and hardness). As a result of these physicochemical properties, changes in perception were observed: the cheeses ripened under 88% RH were dry and hard compared with those ripened under 98% RH. An RH of 98% led to an acceleration of the ripening process, inducing a slightly ammonia and milky flavor and a sticky and creamy texture in the mouth. However, cheeses ripened under 14°C and 98% RH were also indicative of overripened cheeses: a temperature of 14°C induced an acceleration of the ripening process due to physicochemical modifications compared with a temperature of 10°C. Nevertheless, when the cheeses on d 0 were still very humid and soft, those ripened under 98% RH collapsed and were overripened with a liquid underrind. This study provides a means for achieving a better and more rational control of the ripening process in artisanal lactic goat cheeses. [ABSTRACT FROM AUTHOR]

This study evaluated the ability of dairy matrices, different in composition (with and without fat) and structure (liquid and gel), to enhance microorganisms survival through digestion. The viability of three dairy microorganisms Streptococcus thermophilus , Brevibacterium aurantiacum and Hafnia alvei was measured during in vitro and in vivo digestion. S . thermophilus was highly sensitive to gastric stress, and was not found in the duodenal compartment. B . auranticum was moderately sensitive to gastric stress but resistant to duodenal stress. H . alvei was highly resistant to both stresses. LIVE/DEAD confocal microscopy's images, probed the effect of low pH on microorganisms survival. However, in vivo analyses (16S rRNA gene metabarcoding) failed to confirm in vitro observations since tested microorganisms were not detected. Despite of the different evolutions during digestion on buffer capacity, lipolysis, and rheological characteristics, we did not observe any protective effect of the dairy matrices on microorganisms survival. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new simple and easy-to-use dynamic digestion system has been developed. [•] It has been successfully applied to investigate infant formula digestion. [•] The system has been validated towards in vivo data obtained on piglets. [•] Whey proteins exhibited a longer persistence in the stomach than caseins. [•] Caseins were shown to be extensively hydrolyzed in the stomach. [ABSTRACT FROM AUTHOR]

Abstract: The main objective of this work was to determine the highest energy savings that could be made by implementing sequential air ventilation strategy in an industrial large-scale ripening room, without affecting the final cheese quality. Six ripening trials were run corresponding to different ventilation strategies: continuous air ventilation taken as reference, time-based sequential air ventilation, and temperature-based sequential air ventilation. The results showed that ripening caused substantial cheese respiratory activity that was not significantly affected by either continuous or sequential room ventilation. It was also shown that sequential ventilation had no significant effect on the evolution of cheese ripening microbial flora, biochemical characteristics, or appearance, and thus on the final cheese quality. In the conditions of this study, a specific energy consumption of 3.6 MJ per kg of cheese was estimated, and for the ripening room investigated, mean electrical energy savings ranged from 41 kWh per day to 170 kWh per day, depending on the strategy implemented. Industrial operators could usefully study how to generalize these results to the ripening rooms used in cheese production worldwide. [Copyright &y& Elsevier]

Abstract: The potential of near-infrared (NIR), mid-infrared (MIR) and front-face fluorescence spectroscopies combined with chemometric methods was investigated for discriminating Emmental cheeses from different European geographic origins. A total of 91 Emmental cheeses produced during winter in Austria (), Finland (), Germany (), France () and Switzerland () were investigated. Cheese samples were classified by factorial discriminant analysis. From NIR, a good classification of cheeses was observed for 89% and 86.8% of the calibration and validation spectral data sets, respectively. The MIR results were comparable to those observed with NIR. Within the 3000–2800cm−1 region, 84.1% and 85.7% of the cheeses were correctly classified for the calibration and validation data sets, respectively. The classification obtained with the tryptophan fluorescence spectra was considerably lower (only 67.6% and 41.7% for classification and validation spectra, respectively). But tryptophan fluorescence spectra allowed a good discrimination of Emmental cheeses made from raw milk or from thermised milk. Common components and specific weights analysis were performed on the physico-chemical, infrared and tryptophan fluorescence data sets. These results showed that spectroscopic techniques may provide useful fingerprints and allow the identification of Emmental cheeses according to the geographic origin and production conditions. [Copyright &y& Elsevier]

• Food-dependent programme was developed for an in vitro dynamic model of digestion. • Apparent digestibility of nitrogen was consistent in vitro and in vivo. • Both models yielded similar molecular weight distributions of gastric peptides. • Duodenal proteolysis was globally comparable between models. • The DiDGI® demonstrated less inter-trial variability for measured parameters. The present study compared in vivo protein digestion in a miniature pig model with the dynamic in vitro system DiDGI®, using three digestive compartments (stomach, duodenum, and jejunum + ileum). Two soya-based meals—commercial soya milk and tofu—were studied, each with the same macronutrient content but different macrostructures. Our aim was to first deduce from the in vivo experiments in pigs key digestive parameters such as gastric pH, stomach emptying kinetics, and intestinal transit time, in order to design a relevant set-up for the dynamic in vitro system. Then, we compared digestive samples collected at fixed sampling times from both in vivo and in vitro models regarding different values related to proteolysis. We observed similar evolutions of gastric peptide distribution and duodenal proteolysis between models. Overall, apparent ileal digestibility of nitrogen was similar in vitro and in vivo and the differences between the two meals were conserved between models. [ABSTRACT FROM AUTHOR]