Shortening: Its Definition and Measurement - American Chemical

The sum of all the influences of lead subacetate upon the errors of the optical method for. anaIyzing sucrose-raffinose mixtures mould seem, however, ...
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100 cc. of solution caused the direct polarization t o de1.25 and that 5 cc. of hydrocrease f r o m + 1.50 t o chloric acid in 100 cc. of solution caused the invert polariza2.70. The effect of lead tion t o increase from 4- 1.50 t o subacetale, according to the nature of the amino compounds present, might therefore cause an increase as well as a diminution in the errors which these foreign optically active substances produce. The sum of all the influences of lead subacetate upon the errors of the optical method f o r anaIyzing sucrose-raffinose mixtures mould seem, however, generally to be compensa.ting, the errors being usually less \Tit11 than without its use. This is shown by Table 111, which gives a general summary of the results obtained in the analysis of mixtures of sucrose and raffinose with potassium oxalate and asparagine, both in presence and in absence of lead subacetate.

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TABLE 1 1 1 - S ~ o ~ 1 h - 0INFLUDNCE OF IMPURITIES UrJox TEE ESTIMATION OF

Sucrose X o . Per cent I 2 3

50.00 50.00 50.00 50.00 50.00

797

T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY

Sept., 1921

SUCXOSE ASD RAFFINOSE T.AKEN -ORSERTED-CALCULATEDPotasRaff- sium Aspar- Lead inose Oxalate agine SubP P’ Sucrose RaffPer Per Per Aceinose cent cent cent tate 9.25 , .. . .,. , . . +67.13 -7.$55 50.06 9.21 9.2,s 11.54 . . . . . +66.95 -7.57 49.98 9.16 9.25 , , . . . 3.85 . . . . . $66.78 -5.85 47.83 10.23 9 . 2 5 11.54 3 . 8 5 . . . . . +66.80 -5.90 47.89 10.20 9 . 2 5 11.54 3.85 1Oc.c. +65.18 -6.20 48.49 10.09

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There are two possibilities f o r improving the accuracy of the inversion methods f o r estimating sucrose and raffinose-one by the use of a n inverting agent, such as in-

vertase. which avoids the disturbances produced by free acid in polarization of the amino substances, and the other by use of precipitating agents which remoye the acid after inrersion from solution.‘ Both of these possibilities are being examined by the writers, who hope to report upon them a t a later time.

SUXXARY The change in the Herzfeld divisor of the Clerget formula for estimating sucrose from 142.66 to 143 has necessitated a revision of the Creydt formula f o r analyzing mixtures of sucrose and raffinose. I n the course of this revision, the inversion constant of raffinose and the temperature coefficient f o r the polarization of raffinose before and after inversion have been redetermined. The relatire accuracy of this revised formula is illustrated in the case of known mixtures of sucrose and raffinose and in the case of known mixtures of these sugars with potassium oxalate and asparagine when lead subacetate is used as a clarifying agent. Possibilities of iniprooing the optical method f o r analyzing mixtures of sucrose and raffinose are also indicated. ‘ R . F. Jackson and C. L. Gillis (Bureau

01

Standards Scientific Paper

375, 177) suggest a modification of the Creydt method, which oonsiats i n

neutrali ing the inverted solufion with ammonium hydroxide and adding the equivalent amount of ammonium chloride to the solution for the direct polarization, in order to secure equality of condition., before and after inversion. This suggestion, which ha8 not been worked out in detail, deservea consideration.

Shortening: Its Definition and Measurement‘ By Clark E.Davis NATIONAL BISCUITCo., 409 W. 1

The term ‘(shortening ” has never been satisfactorily defined. Still less satisfactory have been the attempts to measure it. The term is used throughout this paper as related to crackers, biscuits, or cakes. The average baker tests the shortness of a cracker in two ways: (1)by its resistance t o breaking, and ( 2 ) by its resistance to crushing. This is natural in view of the fact that in eating a cracker the shortness is first apparent when it is broken, either by the aid of the hands o r by the teeth. It is even more apparent in the chewing operation, which is really one of grinding or crushing. Consequently if some method could be devised which would measure either the breaking strength o r the crushing strength, o r both, it might lead t o a definition of the term “ shortening.” W i t h this idea in mind, a machine bas been devised which will measure either the breaking strength o r the crushing strength with a high degree of accuracy. This machine is simiIar to the forms of cement testing machines commonly in use. These machines, however, are designed f o r measuring heavy loads, and their sensitiveness need not be of the highest order of accuracy. The force required to break or crush any food product, such as those with which we are working, is necessarily very small. This requires that the measuring machine be extremely sensitive in order to obtain great accuracy. I n a cement briquet a force of six, seven, or eight hundred pounds is required, while f o r a cracker a force of two, three, o r f o u r pounds is necessary.

APPARATUS The machine3 described in this paper has been devised for measuring breaking strength and crushing strength. It will be hereafter referred t o as a “shortometer.” I n the drawing, Fig. 1 represents a side elevation of one 1Received May, I;, 1 9 2 1 . 2 Published as Contribution No. 2 from the Research Laboratory of The National Biscuit Company. 3 P a t e n t applied for.

5 ST., ~ NEW ~ YORE,N . Y.

form of the testing device. Fig. 2 is a horizontal section taken upon line 2-2 of Fig. 1, size of base 4.5 in. X 6 in. Fig. 3 is an end elevation of the lower portion of the ap-

T H E J O U R N A L O F I N D U S T R I A L A N D EA'GINEERING C H E M I S T R Y

?Q8

196 Ibs. 35 Ibs. 80 lbs. 43.8 lbs. 0 . 5 Ibs. 0 . 5 lbs. 0 . 3 lbu. 1.5 lbs.

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24 13 2

1 5'

f'

paratus shown in Fig. 1, engaged in breaking a test cake. Fig. 4 is similar to Fig. 3, showing the test of a sample cake for its resistance to crushing. Fig. 5 is a side elevation of a modified form of testing apparatus. I n the apparatus shown in Figs. 1to 4, inclusive, a table, 1, is supported on 3 by means of adjustable screws, 2. A pair of parallel rails, 4, extend upward from table 1to support the cake, 5, when tested for breaking strength. A vertical hardened steel rod, 6, 5 in. long is mounted in vertical hardened steel bearings, 7, formed on a lateral extension, 8, of a rertical standard, 9, which is mounted on table 1. Spindle 6 carries a horizontal support, 10, a t its upper end, on which a shot container, 11, is stationed. The striking member, 12, elongated, in socket 13 with setscrew 14 is detachable from spindle 6 and is preferably rounded and comparatively narrow (See 15, Fig. 3 ) . 1 6 is a guideway for the striking member. When a cake is to be broken it is positioned across the rails 4, and member 12 is placed thereon, while shot is r u n into container 11 until the point of rupture occurs. The container and contents are then weighed. A modified form of apparatus is shown in Fig. 5 in which the spindle, 6', is pirotally connected t o an arm, 17, which is pivoted at 18 to the standard 9'. Arm 17 carries a graduated scale a s indicated a t 19 and a sliding weight, 20. When it is desired to test the crushing strength a portion of the cake, as indicated a t 5' in Fig. 4, mag7 be placed on table 1 between the rails, 4, so that the cake rests firmly on the table. Striking member 1 2 is removed from spindle G by unscrewing set-screw 14. The lower portion, 6,, of spindle 6 has a horizontal bottom surface of comparatively small diameter. Shot is allowed to flow into the container 11until the spindle crushes or pulverizes that portion of the cake against which it rests. The container with contents is then weighed.

flour, medium winter shortening sugar water salt ammonium bicarbonate monocalcium acid phosphate sodium bicarbonate

,111 the experimental batches were 1 per cent of the original formula, This produced 3.5 lbs. of dough. I n order to arrive at some definite method of procedure several hundred batches of cakes, made with the various shortening agents, were tested f o r their shortness. Standardized conditions must be establishea. In the manufacture of a cake there are many variables, e . g., exact amount of material used, method of mixing,' temperature of dough while mixing, time of mixing, the pressure exerted by the brake, temperature of baking oven, conditioning of the cake after baking, etc. In the experimental work these conditions have all been so standardized that each cake gets the same treatment as every other one. The materials are all accurately weighed, the mixing is clone by machine, the doughs are all made as near the same temperature as possible, which is 80" I?., the time of mixing is 7 min., the brake treatment gives all green cakes the same thickness, three-thirty-seconds of an inch, and the cakes are always cut of the same diameter, two and five-sixteenths inches. The temperature of baking is 465" F., and in the reel oven used this was controlled to i 2.5" by means of an electric control of the gas supply. The oven temperature is undoubtedly not uniform throughout, but this irregularity is obviated by the use of the reel oven which takes the cake through the relatively hot and cold zones, thereby giving all uniform treatment. Each batch is baked f o r the same length of time (8.25 min.), determined by the number of revolutions (6). The product is cooled in the absence of drafts to prevent checking. It is then conditioned f o r a t least 48 hrs. in a closed cabinet where the temperature and humidity remain practically constant. At the end of this time the cake is broken in the shortometer. All cakes are of approximately the same diameter and are always placed in the same relative position. Several hundred cakes were used in testing some shortenings, while iii some cases as many as three thousand were used in the standardization of this apparatus. A few results are given, showing the method of recording and the breaking strength of each individual cake in various batches : T A B LI ~ Kind of fat ? i o . I Lard Date of baking July 10 Date of test July 12 79 Temp. of dough, O F . 77 Temp. of room, VF. Temp. of oven, *F. 465 Humidity, per cent 03

EXPERIMENTAL In searching for a type of goods upon which the experiments were to be made it was decided to use a variety of sugar cooky, because the amount of shortening used is a fair average and the cake is easily made. The following formula was used:

Vol. 13, N,. 9

Average

2.63 2.76 2.75 3.13 2.85 3.06 2.88 2.88 2.69 2.94 2.56 2.81 2.51 3.06 3.19 3.06 2.94 2.75 2.88

No. 4 Lard July 26 July 28 81 91 465 62 2.63 3.38 2.94 2.75 2.63 2.94 2.94 2.69 2.88 2.94 2.56 3.19 3.06 3.38 2.88 2.94 2.63 3.26 2.92

It was found impossible to obtain consistent results using hand mixing for the reason that it is never mixed twice alike, the gluten being unequally developed. The machine, KO.7223, of 10 to 12 lbs. capacity, was made by The J. H. Day Co., Cincinnati, Ohio. 7

Sept., 1921

T H E .IOliRAVAL O F IA7DL;STRIAL ii D LITGI-1-E C R ISG CH EA\IIST R Y T.4BLE

I1

hind of Fat CXHYDEOQES.4TED O I L I I S D R O G E S 1 T E D CIL Date of baking Dec. 31 Dec. 31 Dec. 10 Dec. 12 Dec. 13 Dee. 17 Date of test Jan, 2 Jan. 2 Dee. 13 Cec. 14 Dec. 16 D e r . 19 SI so '70 68 80 Temp. 01 d o u g h , "F. 50 Temp. ai' room, O F . 10 72 80 SO 78 i6 Temg.Lr oven, Q F . 463 465 465 466 452 465 38 45 55 39 35 48 Humidity, per cent Breaking strength, Lhs. (14 tests) (14 t?sts) (14 t?stn) (18tests) (18 tests) (17 t e s z ) 3.69 3 '75 4.13 3.75 3 84 High 3.88 2 8s 2 88 3.13 2.94 3 13 Low 3.50 3.28 3.26 3 21 3.E4 3 72 A vel'age 3.71

It is obvious that there are no great differelices in the individual cakes. The general arerages check very closely. An accuracy of 1 to 2 per cent is readily attainable. After the coiiditioiis h a w been standardized it is not necessary to use more than thirty cakes for each tzst. ' Similar series with other oi!s, nnhydrogeiiated and hydrogenated, seem to sh0.s that hgdrogenatioii results in greater shorteiiing power. Measurements have been inaclss of tlie shortening power of the following oils and fats : Lard Lard compsund Buttes Cottonseed oil Cottonseed oil, hydrogenated Coconut oil Cocznut oi., h:;drJpenatezl

Corozo (cohune nuti oil Corn oil'

Olive oil Peanut oil Peanut oil, hydrogenated Rapeseed oil Soybean oil

I n all the comparatire breaking tests made on vaiions oils and fats, lard is the best shortening agent; hence it is use:? as the standard. I t s breaking strength will vary aecordiiig to the conditions of standardization, and each operator must determine the value to be used as a standard. The shortoineter value in pounds is arbitrarily taken as 100 per cent. All other oils and fats having less shortening power will have a greater shortoinater value. This weig!qt in pounds of the standard divided by the weight in pounds of any other oil or fa,t will give its relative shortening value. Experiments determining tlie crushing strength are not included in this article, but the same relatioiiship holds.

799

CLASSIFICATIOP;01 FLOTX~ By liolding all other ingredients constant aiid varying the flour usnd it is possible to arrive a t a satisfaetory classification of flours.' A few result; on flour are showii: CLASSIFICATIOS OB FLOUR

BRWXIXG8 T R D N Q T l I Lbs.

Soft n-inter Soft minter Soft nintes Soft winter l~lediumn-inter Medium ninter Medium n5nter Strong winter Strong n-inter Strong winter Spring Spring Snring

2 49 2 33 2 48 2 42 2 69 2 79 2 78 3 ni 304 3 07 3 39 3 39 3 09

DEFISITIONOF SHORTENSWQ Thai cake which requires the least load to measure its breaking strrng,h is the shortest, that, which requires the heayie-t h a d is tlie least short. The b e s t shortening is that material which when baked in a do~-igli gives to the product :L ininimum breaking styength arc1 a ininimum crushing strength. SUMMARY

I-Apparatils has been devised which will measure the shortening value of different oils and fats and mixtures of them. 2-Shoitening has been defined in terms of measurable units. 3-Lard has been found to be the best shortening agent. &Partial hydrogenation of a n oil increases its shortening power. 5--A method has been suggested whereby flours may be classified. Further n-ork is being done alcng this line.

A Process for Producing Palatable Sirup From Sugar Beets By Sidney F. Sherwood 3FFlCn OF s U G h R - P L 4 K T ISVDSTlGATlONs,

B E R B ~ OCF

P L 4 N T IKDU-TRY,

The S u g a r B e e t (October 1906) refers to tlie \tir> objectionable flai-or aiid odor of sirup prepared from sugar beets and states that during the preceding fifty years numerous experiments had been inade t o eliminate this, but that all of the processes suggested were worthless. The same journal ( J a n u a r y 1908) contains a brief note stating that "excellent" sirup is made from beets i n Belgium and Germany by cooking the beets in mater for several hours, pressing out the juice apd evaporating directll- to sirup of about 75 per cent solids; the statement is made also that about 70 g. of suliuric acid are added t o the extract from 1 0 0 k. of beets. I n 1917, C. 0. Townsend and W. C. Gore" described a process. the essentials o€ which consisted in reducing the beet roots to thin slices, extracting t!ic sugar by m e a i i ~of hot imter, drawing off tlie sugar solution €rom the beet chips, and subjecting it to slow and long continued boiling and constant removal of scums during the process of evaporation. Acceptable sirup could be produced by the process recommended, but in a great many cases the odor nnd flai-or TT as highly ol?jectionable, while the sirup mas a1x-a.m ~ e r ydark in color. I n January 1919, the writer suggested iiiiprovements in the process, the use of \%-hieli Received J u n e 0, 1cJ21. " Sugar B e e t Sirup." U. S . D e p a r t m e n t of A4griculture, lial-?ne?s' Bullettir, 523 (1917).

DDPLI~TVEXT O F .\GRICULTURE,

~'AsHINGToY,

D.

c.

resulted in marked improvement in the quality of the sirup produced. These suggestions vTere attached in printed form to copies of the bulletiii sent out thereafter, and included thorongli ripeness of the beet, removal of the top and upper green colored portions, removal of the skin, perniitting the slices to fall directly into water of sufficient depth to prevent access of air and consequent oxidation and darkening of the slices, and direct evaporation to sirup. John 31. Ort and James R. Vithrom, mho investigated the preparation of beet sirup, n-ere iinacquainted with the fact that this improved process had been offered a t the time they presented the results of their investigations before the Division of Industrial ai?d Ecgiiieering Chemistry at tlie 57th Meeting of the American Chemical Society, B~iffalo,K. Y., April 7 to 11, 1919, but refer to it in their publislied article,I and state that the precautions used are similar to those used by them and that the results obtained shoulcl be better than in the case of the original method. They triad many chemical and mechanical processes fo! c,larificatioii and removal of objectionable odor and flavoi aiid state that none of them resulted in marked improvement in flavor. Identical results have been obtained by the writer in using inally similar processes, and it is concluded that it is not advisable to suggest chemical processes a t all f o r use where the sirup is to be produced upon a small I THIS JOCRSAL, 1 2 ( 1 9 2 0 ) , 154.