212
FREEZE—DRYING
,
method of sterilization thatit can penetrate into and throughout the material. At the
dose levels needed (approximately 1 mégarad), the undesirable‘ changes in organoleptic
_
properties of the spices should be minimal.
.
MODIFICATION OF TEXTURE
O_F DRIED FOODS
‘
A great deal of work on the texture of irradiated foodstuffs of various types was done in
the 1950 's. In particular, it has been shown by Kertesz and his co-workers [(Glegg, Boyle,
Wilson, and Kertesz, (1956); Boyle, Kertesz, Glegg, and Connor, (1957); Kertesz,
Glegg, Boyle, Parsons, and Massey, (1964); Kertesz, Schulz, Fox, and Gibson, (1959); and
Massey, Taman, and Kertesz, (196l)] that ionizing energy appears to « soften » or damage
the texture of irradiated fruits and vegetables. In studies on the esh of seven varieties
:gÏÎëï
of apples and ve varieties of carrots, Boyle, Kertesz, Glegg, and Connor (1957) found a
threshold dose at which a measurable change in texture occurred, and the work suggested
a possible common denominator in the irradiation—induced softening of apples and canots.
,
‘
In further studies, Kertesz, Glegg, Boyle, Parsons, and Massey (1964) observed degradation
'
in both the pectic and cellulose constituent of apple, carrot, and beet tissue. In the case
of apple tissue and carrot tissue, the degradation of both of these constituents occurred
at approximately the same dose at
tiSsuë softening could be rst demonstrated,
and progressed with increasing dose. In the case of beets, marked changes in cellulose
and pectin were notobserved, and it is suspected that other factors such ,as cell turgidity »
are involved inthe
McArdle and Nehemias (1956) showed “a relationship
'
‘
-
betWeen radiatidnändubèd
of apple
tissues, a decrease in pr0topeCtin
.
and total pectic substances and an increase in soluble pectin and pectate.
;
…
_
1‘
_In order to get further background on the effect on plant tissues, _G_legg and Kertesz
(1957), Kertesz, Schulz, Fox, andGibson (1959), and
and,LàVin
(1956)
studied the effects of_ionizing energy on cellulose, ,starch,
in model solutÎÔÏIS. _ '
,
,
‘Pu
‘.
—_
*
‘=
…
‘
‘
.
Somogyi and Romani (1964) studied the texture changes in irradiated"fruits and its
relation to pectin
pears and ïpeaches and‘found‘va' decreasein the“prôtopectin content and an increase ,in,fche,
of the fruit _as well
as a softening in the fruit.
,
Naik-Kurade, Livingston, Francis, and Fagerson (1959) also demonstrated the loss of
,
gelation in pectic
viscosity of
sauce,,
effects of ionizing
_
energy on natural
the book
(1958).
The-above and other researches have led to a patent by Schroeder (1962) of the Thomas
Which uses
soupæm‘ixes: …
'
.
1eve1suptomMevthe maxmumlaæ1
…
’
Adm1mstraüonat the present time
‘
,
_
”
_
_Ë}_
_
__
“
'
ependentonthedosebemgusedofcoursesomedegreeofstenhzatlonlsachœved
'
concomantwûhthesoftenmgtreatmmt
FREEZE—DRYING
,
method of sterilization thatit can penetrate into and throughout the material. At the
dose levels needed (approximately 1 mégarad), the undesirable‘ changes in organoleptic
_
properties of the spices should be minimal.
.
MODIFICATION OF TEXTURE
O_F DRIED FOODS
‘
A great deal of work on the texture of irradiated foodstuffs of various types was done in
the 1950 's. In particular, it has been shown by Kertesz and his co-workers [(Glegg, Boyle,
Wilson, and Kertesz, (1956); Boyle, Kertesz, Glegg, and Connor, (1957); Kertesz,
Glegg, Boyle, Parsons, and Massey, (1964); Kertesz, Schulz, Fox, and Gibson, (1959); and
Massey, Taman, and Kertesz, (196l)] that ionizing energy appears to « soften » or damage
the texture of irradiated fruits and vegetables. In studies on the esh of seven varieties
:gÏÎëï
of apples and ve varieties of carrots, Boyle, Kertesz, Glegg, and Connor (1957) found a
threshold dose at which a measurable change in texture occurred, and the work suggested
a possible common denominator in the irradiation—induced softening of apples and canots.
,
‘
In further studies, Kertesz, Glegg, Boyle, Parsons, and Massey (1964) observed degradation
'
in both the pectic and cellulose constituent of apple, carrot, and beet tissue. In the case
of apple tissue and carrot tissue, the degradation of both of these constituents occurred
at approximately the same dose at
tiSsuë softening could be rst demonstrated,
and progressed with increasing dose. In the case of beets, marked changes in cellulose
and pectin were notobserved, and it is suspected that other factors such ,as cell turgidity »
are involved inthe
McArdle and Nehemias (1956) showed “a relationship
'
‘
-
betWeen radiatidnändubèd
of apple
tissues, a decrease in pr0topeCtin
.
and total pectic substances and an increase in soluble pectin and pectate.
;
…
_
1‘
_In order to get further background on the effect on plant tissues, _G_legg and Kertesz
(1957), Kertesz, Schulz, Fox, andGibson (1959), and
and,LàVin
(1956)
studied the effects of_ionizing energy on cellulose, ,starch,
in model solutÎÔÏIS. _ '
,
,
‘Pu
‘.
—_
*
‘=
…
‘
‘
.
Somogyi and Romani (1964) studied the texture changes in irradiated"fruits and its
relation to pectin
pears and ïpeaches and‘found‘va' decreasein the“prôtopectin content and an increase ,in,fche,
of the fruit _as well
as a softening in the fruit.
,
Naik-Kurade, Livingston, Francis, and Fagerson (1959) also demonstrated the loss of
,
gelation in pectic
viscosity of
sauce,,
effects of ionizing
_
energy on natural
the book
(1958).
The-above and other researches have led to a patent by Schroeder (1962) of the Thomas
Which uses
soupæm‘ixes: …
'
.
1eve1suptomMevthe maxmumlaæ1
…
’
Adm1mstraüonat the present time
‘
,
_
”
_
_Ë}_
_
__
“
'
ependentonthedosebemgusedofcoursesomedegreeofstenhzatlonlsachœved
'
concomantwûhthesoftenmgtreatmmt