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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.

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Polymer networks applied in clinical dentistry can be divided into two groups: (i) hard, solid two‐and threedimensional crosslinked structures formed during photo‐curing of dental polymeric filling compositions, and (ii) soft, hydrogel‐type of networks based on polymeric ionic complexes, used for the tightening of microchannels in teeth. The first group is based on crosslinked di‐ and trifunctional monomers, and on solid poly(acrylic acid) ‐ inorganic glasses (“glass ‐ ionomer cements”) This group has found wide clinical applications, in spite of many disadvantages such as susceptibility towards hydrolytic, mechanical. bio‐ and enzymatic degradations, and contents of toxic, allergenic and mutagenic components. The second group, the soft‐hydrogel type of networks, has been investigated and developed at our institute in order to tighten channels in teeth. The microchannels, with a diameter of 30–200Å in enamel and 1–3 μm in dentine, are filled with a loose, native bio‐hydrogel of protein origin. Hydrogels have the ability to swell in water of biological fluids present in the oral cavity, and can retain a significant fraction of fluid within the structure. Decreasing pH below 5.5 causes a slow dissolution of the hydroxyapatite crystals in the walls of the microchannels with a consequent widening of their lumens. Metabolites and toxins from microorganisms, which are always present in the oral cavity, can penetrate into these enlarged channels and cause inflammatory reactions in the underlying pulp tissue. In order to decrease fluid flow and inhibit penetration of microorganisms, but still allow diffusion of ions and water, we have developed and tested polymeric hydrogels based on poly(acrylic acid) and metal salts, and chitosan, which can be formed directly in the micro‐channels of dental hard tissues.