The effect of extended milking intervals (24, 48 and 72 h) on milk yield, milk composition, mammary physiology and welfare traits in dairy ewes.

The majority of the work today regarding the effects of extended milking intervals has focused on dairy cattle and only to a limited extent on dairy goats and sheep. The aim of this study was to investigate the effect of different non-milking intervals on milk yield and composition, mammary physiology and welfare indices in dairy ewes. Thirty-six multiparous ewes in late lactation were allocated to one of four groups of nine and subjected to 24, 48 or 72 h of non-milking or normal milking interval (12 h) (group A, B, C and D, respectively). Data showed that there were no significant differences in milk yield among the experimental groups during the third day after re-milking. Furthermore, no significant differences in milk lactose, protein and fat concentration among the experimental groups were observed after 7, 14 and 21 d of re-milking, respectively. Non-milking for 72 h resulted in a temporary increase of sodium concentration, Na + /K + ratio and enzymatic activities of plasmin (PL), plasminogen (PG) and plasminogen activator (PA) in milk. However, these parameters had similar values among the experimental groups on day 5 after re-milking. The concentration of lactose in blood was also significantly increased as a result of the 72 h non-milking interval and returned to its initial levels the second day after re-milking. These data, taken together, suggest that early involution events that occurred as an effect of non-milking were fully reversible within a short period of time. Finally, no significant signs of welfare impairment were observed in ewes due to extended milking intervals. In conclusion, non-milking up to 72 h had no negative effects on milk yield and composition, mammary physiology and welfare parameters in dairy ewes.

Evolution of microbial populations during traditional Feta cheese manufacture and ripening.

In three different dairies (A, B and C) located in Peloponess region (Southern Greece), traditional Feta cheese trials took place February to March using mixtures of sheep's and goat's milk. Only small variations in the evolution of microbial groups were observed during the whole ripening period. The main groups, such as thermophilic cocci, mesophilic lactococci, thermophilic lactobacilli, nonstarter lactic acid bacteria (NSLAB), presumptive Leuconostoc, enterococci and micrococci, reached their highest levels during the first 16 days, and then declined approximately 1-2 log units until the end of ripening. The remaining groups investigated, comprising yeasts, coliforms and Escherichia coli, were highest at day 4. The yeasts remained constant, while coliforms and E. coli decreased sharply and were not detectable after 120 days of ripening. A number of 146 isolates (dairy A) taken from all stages of the manufacturing and ripening process were purified and studied. Lactobacillus plantarum (58/146) and isolates of related species Lactobacillus pentosus and Lactobacillus paraplantarum (16/146) were the most common microorganisms found during cheese ripening. Streptococcus thermophilus (23/146) and Lactobacillus delbrueckii subsp. bulgaricus (20/146) were detected in high levels up to 20 days, and then gradually reduced. Enterococcus faecium (29/146) was found in all manufacturing and ripening stages.

Identification of Throuba Thassos, a traditional Greek table olive variety, as a nutritional rich source of oleuropein.

The content of polyphenols in table olives is highly influenced by the olive variety and the debittering process applied on the fruits. Nine commercial types of Greek table olives were examined for their content in oleuropein and hydroxytyrosol. A very simple extraction procedure and a chromatographic methodology were applied for the simultaneous quantitation of oleuropein (OE) and hydroxytyrosol (HT) in drupes, using boiling water extraction followed by direct HPLC analysis. Hydroxytyrosol was found in all the types of olives that were studied. Kalamata olives and Green "tsakistes" of the variety Megaritiki contained the highest quantity of hydroxytyrosol (1.8-2.0 mg/fruit) followed by Greek-style "chondrolies" with quantity 1.0 mg/fruit. Oleuropein was found in small quantities in two cases, but in the case of Throuba Thassos which is processed by dry salt in a traditional Greek way, oleuropein was found in important quantities (1.2 mg/fruit) recorded over a 4-year period. This is the most important finding of this study showing that this particular table olive type is a nutritional rich source of oleuropein. Additionally, assuming a usual consumption of 20 olive fruits per day, an approximate quantity of 25 mg of oleuropein per day can be considered as safe for human use, since it can be found in the usual diet.