—

Se ae

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Sia iee eet baked ey at

of Miergs Organisms In
Spoiled Canned Fruit

Fleta Paddock.
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a eee een ee ne. anal
SHESID
THE THEERMAL-DEATH-POINT

—

OF MICRO-ORGANISMS

FCUND IN

"SPOILED" CANNED FRUIT.

Fleta Paddock.

Miehigan Agricultural Coliege.

1901,
JHESIE
on

THE THERUAL-DEATH-POINT
OF MICRO-ORCANISMS
FOUND IN

"SPOILED" GCGANUE D FRUIT.

In order to detervizne wiiocther tie v.resence of

icro-organisrms in "spoiled" canned Fmit is Are

tne “eat resisting power of thes micro-organisms,
cones AuO't throuch lgnerance or carulensness

aa a ~ st . * ‘ ere eN 7 + ~* ce we *. ™ = ;
tle part ov the porcon working with the: fruit,

fie trernval-—-deasth-—-point of several beeteoria are

molds tasen Prom cuntiecd rruit in dirrere: t syns

or

. a .. _ ; _
decerposition ee seen ascertainoad,

Gelatis:e wieates were iiace from the cus or

rruit secured, and tye colonies cr bacteria and

molds that «7 ered vere careru.ly examined in

order to aet rmeinc tire aivrerent kinds. Arter com

pArTIison ty peans of the 2Avwans drop, moist cncasber,

won bo >

steb cultures, a2d poullion cra milk tubes, «1x

Ow
ca
rie

lade, is a@ micrococcus, 91.9 nas a Strikin:

stereia and six rolds wers iscliutend,.

Germ A, wich was lsolmted rroi a cun or mMar-

L'
y

4

2

{
ae

pigeent. It rows Slowly without Liquifying te

7 4 * Pe tao) ~ ’
Pl. tine Corm Rovas obteined verom a enn of precn-

5 _* 7 7 *-— ,> "a ~ +
~ A ara B were the ory gormss that ois nor

liguify -elatine, Prt P aitfers from A im other

-HOCTS. It vorns a ropy, white sedi.cnt in

1082218
boultlion. Ceres ¢ eae ) ciuusce Prom @ Gc .n oF bears
Toey @po seth inlerocogzl, #4 “oth liauivry Selutine,
“at © liaguifles 1t more quickly than bp. Irn bouillon
Goween se rovy, vellie D rorms a flaky wnite sedi-
pent eacily e1sturbed. ¢ solidiries milk. Ih alia
Poou.o trom a een ot er ples. bh was isolated trom
‘elev tie surface and FY Prom tiie surivace. "

LEG Voeg the gcelatiie vo ry olovily. Like ¢, it
coarnletes milk, butjun:ike co, 1% causes the milk
FO rea,din in a colid ievmr. Fo ane F are micro-

eocel Four? oth sire: y @edoin pulirs. F Liquiries

FS
MO

adly a ac hes & yollow tvigment. It Yormrs a little

sediivent in tiie pottom of boutllon tu. oc whien 1s
eet easily ssipcien up,

-olas A an® R esve with Germ E from beneath
ts surface ov the enor a; vles. Moids © ann D

.

“were onoteined from aoen or perve.es. These vour
molas are varieties of Penicillium. volt b ce: e¢
“th Germ F feom survece of a can of «:.v7les. [ts
cpove Tervation fAiffrers tvom that of Penicilliuna
cad reselicles potrvtis. Pole Fo eave rrom below the
srrrace or een of niles. It is 7 dark brown rold
and nas a peculiar spore Povrstion Aivvering from

tint of 2.11 the atier molds,-

Teroivye fFrochn bouillon cultures were wate of
 
©. (YEOVOS 7 6a > + 2s . 4 x ) 7 ~ ~ 8 i

biCSE Pee tewyla ii iIncolds preparatory to the deéter-

minati P40 te eg thong ;
ation of tac ticrral-denath-point. Twelve tubes

oy , 7 VARA Trormemn +7 ; . 1
er boutllion were then pleced ina wot veter bath

we OR URS LE
AYN MQ aac + vay ame a ° ]
ann raised to a tempcrsture of 55 Centicsrade.

These were inoculated trom the twelve tuses or

ve AD

abe

ocacter ia aid molds. They were Lert in the bath

rive reinutes after inoculation ith a constant

atl

4 7M 7 1 > 0 Mm .
vcenerature of £5 ¢. Tiey vere ticn menoved aia

y ’ vr + - . 2 = ° :
dcediiately cooled. APU r tan devs, wera vnicn

oe

“29

the tuves nadiecn in a teiperature vavorable to
a 1; 5 ry a q 3 - — . _ . Sy .

aie frovth of those micro-organisms, they were
exanilued ror traces ocr grovtn. All hed grown but
liold FTF.) Tire exverlwenrt was reveated with tne

otner molds and the vceeteria, Lut at a higner
Femcerature. TRio wae continiucda until ail were
killed, The temeerature ut which each micro-
opcenism vas killed is shown in the following

Table,

 

racteria Eh* ¥GO" WEB™ 7O™W F5™ "GO™ MAE" NGOMOEON IO”

an

 

 

 

 

 

 

 

 

 

 

A — t t tt tf t t tt ny i"

B _ wt 1 w wo re " " 1 !

C _ " wo tt no Wy t 1! " "

D _ 1 1 Y t Wn " tt ! "oy
E _ Tr WT " + 1" " " tt ! ue _
r TT wT _ $ D " " 1" " tt ee

 

 

 

 

mr

Molds _ . ee

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A vY + a it t tt t

vr " rT] tw at 1" 1! "
B _— — tt + [
C — i © "f 't '! ! tt " ! 1 —
D _ tf " " " " " i" " "

OO TO "

Ki — ! " tt ! 1) " 't Tt]

" " "1 tt " t? t? " a

:
no molds were Kilied at = lover temperature
ten tne bacteria. Wold Fo vas killed at 55
A, C, Dand Boat 60, ara R at 65, while the bacteria
| . 0 . |
resisted hest until 70 was reached, “hen kb and F
tailed to grov. R ad@ were ki-led at 30°

A ard D were tre inset obstinate, but were killed

-ectively.

nb 95° ard 100% res
AS Gil these micro-organisms way be kitted

by “oiling (100°C) it follows that tleir growth

In tie cansed Pruit was net “ve to the heat resist-

ant power of the micro-orvcrnisme, “ut to tre lack

or
we

> Je 7
Gr knevled.

or, or carelessness in, the operation

eo.

of cerning. SutPicie rt care was ret given to the
cleanliness end sterilization of cloths and utensils
used, thereby alloving free access of tne low Lorms

of plent lite.
—_ - 8 ee OE