SU1739283A1 - Method of assaying artificially dried grass feedstuffs and arboreal green vitamin meal for carotene - Google Patents

Abstract

The invention relates to agriculture and can be used in the feed industry and in the Agroprom system for the determination of carotene in grass, artificially dried, and vitamin flour from wood greens. The aim of the invention is to accelerate the determination of carotene. The method is carried out as follows: a mixture of feed with aviation gasoline B-70 or petroleum ether is treated with ultrasound of low frequency UZDN-1

Description

The invention relates to agriculture and can be used in the feed industry to determine carotene in dried grass feeds and vitamin flour from wood greens.

The purpose of the invention is to reduce the analysis time and simplify the process.

Example. Take 0.5-2 g of grass meal or vitamin flour from wood greens, put into a 100 cm3 conical flask, add 50 cm3 of B-70 aviation gasoline or petroleum ether and treat with ultrasound at a low frequency UZDN-1 (22-M kHz) for 2 min (when sonicating, the flask with the contents must be kept in cold water).

Cotton wool is tightly placed in a narrow part of the column so that in the wide part of the column the wool is approximately 1 cm, on top of which the adsorbent (alumina 10% humidity) is filled with a layer of -5 cm. The column is inserted into a Bunsen flask. 250 cm3.

Under a weak vacuum, the extract is drawn through the adsorbent and immediately washed with gas. Washing about

WITH

with y

00 GO

worn away until the last drops of gasoline are colorless.

For mass analysis, it is possible to take Four Bunsen flasks, connect four columns between each other with a tee and simultaneously adsorb two samples with two parallel determinations.

At the end of the adsorption, the volume of the extract is measured by a measuring cylinder, the photoelectric colorimeter with a translucent layer thickness of 20–30 mm is transferred into the cuvette and proceed to photometry.

In the photometry of carotene extract, the comparison solution is aviation gasoline B-70 or petroleum ether. When the optical density of the solution is 0.6–25 cm3, the exhausts are transferred to a measuring flask with a capacity of 50 cm3 and brought to the mark with gasoline or petroleum ether.

The results of carotene detection in this case are doubled.

The mass fraction of carotene X in 1 kg of feed, mg, is calculated by the formula

x

 0 00416 V: 1000

where a is the equivalent amount of the basic solution found on the schedule, cm3; V is the volume of the test solution,

cm3-

m is the mass of the sample, g; 0, is the conversion factor of 1 cm3 of the basic solution of potassium bromobutyric acid into an equivalent amount of milligrams of carotene;

100 is the volume of standard solutions taken to prepare a calibration scale, cm3 ;. 1000 - conversion factor to

1 kg of feed.

The results are rounded to the nearest whole number. The final test result is the arithmetic average of the results of two parallel determinations.

The permissible discrepancy between the / results of the two parallel definitions d and between the two results obtained in different conditions D (in different laboratories, in different time, when working on different instruments, etc. should not exceed the following values:

, 05 X; . , 65 + 0.22 X,

739283

where is x

15

20

arithmetic average of the results of two parallel determinations, mg / kg;

. X is the arithmetic average of the results of two tests performed under different conditions,

MG / KGo

The permissible discrepancies d, D between JQ and the results of the determinations are calculated with a confidence probability, 95.

In tab. Figure 1 shows the effect of sonication on the carotene extraction process.

From tab. 1 it follows that during sonication, the maximum extraction of carotene occurs during sample processing for 2 and 3 minutes. The test results are identical, the difference is minimal. Therefore, the duration of the ultrasonic treatment of a sample of grass meal and vitamin flour from wood greens can be considered 2 minutes.

The results of analyzes during ultrasonic treatment correspond to the results obtained in accordance with GOST.

In tab. Figure 2 shows the effect of different values of the ultrasound frequency.

The technical capabilities of the device are limited to two fixed frequencies - 22 and kb kHz. From a practical point of view, the oscillation frequency is not significant, however, with radiation of 22 and kk kHz, almost identical results were obtained, the difference between them is not significant, 2,3.

25

thirty

40

4S

50

55

t f toflS

The results of the metrological characteristics of the accelerated method for determining carotene are given in Table 3; data on the time spent in the analysis - in the table, 4.

The proposed method will reduce the analysis time from 14-18 h to 30 min. In addition, it only uses one adsorbent instead of three.

Claims (1)

Invention Formula The method for determining carotene in grass feed, artificially dried, and vitamin flour from wood greens, including chopping the feed, extraction with a solvent — aviation gasoline B-70 or petroleum ether followed by photo5. 1739283 Metricating solvent-treated ultrasound so that, in order to speed up the process, a mixture of powdered feed with com power W frequency of 22 kHz for 2 min. the solvent is treated with ultrasound com power W frequency of 22 kHz for 2 min. Note. 15-iZz 4.65; h - 6Ґ - 3, the difference is not reliable, t o, 1 Table 1 table 2 ten  or 1080 (h) 3 C 3 86 min 1A h 27 min or 1107 min 18 h 27 min Table 3 Table k ten four 3 30 min