摘要:
An apparatus for taking out an average sample of milk proportional to the yield from the milking of a cow. The apparatus comprises a primary sampling system and a secondary sampling system. The primary sampling system has a chamber into which milk is sucked during the milking of the cow through a first tube terminating at a distance from a superimposed circular cylinder the bottom of which forms a substantially horizontal circular distributor surface which spreads the milk to form a film. A fraction of the film is caught between a first pair of knives, which are not integral with the distributor surface, and passed through a normally open valve into a collecting cup, while the major part of the milk leaves the chamber through a discharge tube in the bottom of the chamber. The secondary sampling system is adapted on completion of the milking to suck the milk from the collecting cup upwards into the chamber through a second tube extending from the bottom of the collecting cup and terminating at a distance from a superimposed second circular cylinder the bottom of which forms a second substantially horizontal circular distribution surface which spreads the milk to form a film. A fraction of that film is caught between a second pair of knives, which are not integral with the second distributor surface, and led down into a test cup, while the major part of the milk from the collecting cup leaves the chamber through the discharge tube in the bottom of the chamber.
摘要:
This invention provides for an analytical apparatus for serial determination of nitrogen in samples by the Kjeldahl method, characterized in that it comprises from 4 to 7 flasks suspended vertically in a rotatable roundabout, each provided with a cover and a side tube extending into a common central container for the collection of combustion products, the roundabout being connected to a device which at regular intervals turns the roundabout one step forward to the next position, means for heating the flasks in one or two of the positions, means for blowing cooling air against the flasks, means for feeding diluent water to the flasks in a following position, means for introducing neutralising chemicals, means for generating and feeding steam to the flasks in the next following position, means for collecting and titrating the distillate, blowing means for emptying the flasks in the last position, and means for opening the covers on completion of the decomposition and for introducing diluent water into the flasks.
摘要:
A method is disclosed for conditioning samples (of e.g. milk or meat) containing fat globules and somatic cells and/or protein particles before they are subjected to fluorescence measurements in order to determine the bacterial content, as well as methods for performing the determination of bacterial content in such samples. The conditioning method involves the treatment of the samples with an ion-chelating agent, a proteolytic enzyme, detergent, and a bacteriologically specific fluorochrome such as ethidium bromide. Detergent is used in a concentration resulting in substantially no dissolution of the fat globules and the conditioned samples thus loses insignificant amounts of fat globules. The assessment of fluorescence is preferably performed in a conventional flow cytometer. As no separation of fat globules is necessary, the methods are simple and fast. The bacterial determinations have proved reliable when compared to standard methods.