In mammals, odorant binding proteins may play an important role in the transport of odors towards specific olfactory receptors on sensory neurones across the aqueous compartment of the nasal mucus. We have solved the X-ray structure of such a transport protein, bovine odorant binding protein (OBP) at 2.0 A resolution. The beta-barrel of OBP is similar to that of lipocalins, but OBP dimer association results from domain swapping, an observation unique among the lipocalins. The alpha-helix of each monomer stacks against the beta-barrel of the other monomer. Contrary to previous reports, each monomer has an internal buried cavity which could accommodate a naturally occurring molecule. Besides this cavity, an open cavity is located at the dimer interface. Data in solution suggest that this central cavity may be a binding site created by domain swapping.

Cow nasal tissue contains a protein which shows specific binding activity for ‘green’ smelling compounds such as 2‐isobutyl‐3‐methoxypyrazine. This protein has now been purified using anion‐exchange fast protein liquid chromatography. The protein has a relative molecular mass of 400000–44000, s= 3.1 ± 0.3 S, pI = 4.7 ± 0.1 with an absorbance maximum at 278 nm, and consists of two subunits with an identical relative molecular mass of 19000. It is localised in the soluble fraction of cells from the olfactory mucosa and respiratory mucosa from the middle part of the maxillary and nasal turbinates, and is absent from all other tissues tested.

To understand the concept of "total food quality" and how it has evolved, we give a brief historic outline from Pasteur to the recent rise of the globalized market. Nowadays, "total food quality" is clearly a partially objective concept in the sense that it can be defined according to scientific and technological criteria and partly subjective because consumers' judgments, mainly based on their appraisal, may equally concur in its definition. Food properties contributing to "total food quality" definition and assessment include (1) organoleptic and sensory attributes, (2) food safety, (3) nutritional value, (4) functionality, (5) service and stability, (6) wholesomeness, and (7) psychological factors. Many technological and gastronomic treatments may alter food components, e.g. fats, proteins, and vitamins (the most sensitive to physico-chemical changes in the environment), thus, negatively affecting any one of the aspects of quality in the above list. Specific analytical strategies and sensitive appliances can be utilized both to assess and protect food quality and to correctly conduct and monitor food production. Among the so-called psychological factors, however, there are some molecular aspects that are still elusive, although of enormously great interest. In fact, food can have some psycho-active effects on the consumer, thus, influencing his or her behavior during either pre-ingestive or post-ingestive phases. As studies of psycho-active substances in food seem to be opening up a new scenario in "total food quality" research, the gathering together in a single chart of all the information on the effects of food on its journey, from sight to ingestion, would seem like a good basis for a more rational and thorough discussion of the topic.

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Polyclonal antibodies have been raised against purified bovine pyrazine-binding protein, a protein that binds the odorant 2-isobutyl-3-methoxypyrazine. These antibodies have been utilized in immunocytochemical experiments to localize the pyrazine-binding protein in bovine nasal mucosa. Tissue fragments, macroscopically identified as olfactory and respiratory mucosa, were fixed in Bouin's fluid and embedded in paraffin. Consecutive serial sections were processed for immunofluorescence studies and restained either with haematoxylin-eosin or with periodic acid Schiff-Alcian Blue. In both olfactory and respiratory mucosa, only seromucous tubulo-acinar glands were specifically labelled. These glands are located in the lamina propria underlying typical respiratory epithelium, even in those tissues that are macroscopically defined as olfactory mucosa.

Calcium is recognized as an essential nutritional factor for bone health. An adequate intake is important to achieve or maintain optimal bone mass in particular during growth and old age. The aim of the present study was to evaluate the efficiency of hake fish bone (HBF) as a calcium source for bone mineralization: in vitro on osteosarcoma SaOS-2 cells, cultured in Ca-free osteogenic medium (OM) and in vivo on young growing rats fed a low-calcium diet. Lithotame (L), a Ca supplement derived from Lithothamnium calcareum, was used as control. In vitro experiments showed that HBF supplementation provided bone mineralization similar to standard OM, whereas L supplementation showed lower activity. In vivo low-Ca HBF-added and L-added diet similarly affected bone deposition. Physico-chemical parameters concerning bone mineralization, such as femur breaking force, tibia density and calcium/phosphorus mineral content, had beneficial effects from both Ca supplementations, in the absence of any evident adverse effect. We conclude HBF derived from by-product from the fish industry is a good calcium supplier with comparable efficacy to L.