influence of pre-processing storage conditions on peeled almond quality

12 Pages·2008·1.45 MB·English

PAPER
INFLUENCE OF PRE-PROCESSING
STORAGE CONDITIONS ON PEELED
ALMOND QUALITY
INFLUENZA DELLE CONDIZIONI DI CONSERVAZIONE
PRE-LAVORAZIONE SULLA QUALITA. DI MANDORLE PELATE
E. SENESI, A. RIZZOLO, C. COLOMBO and A. TESTONI
Istituto Sperimentale per la Valorizzazione Tecnologica dei Prodotti Agricoli (LV.T.P.A.),
via Venezian 26, 20133 Milano, Italy
ABSIRACl' RIASSUNfO
The study was can1ed out to deter Sono riportatf.l rtsultatf. di una ricer
mine the effect of storage conditions ca tesa a valutare la possib1l1ta di otte
(in-shen, shelled, storage time and tem nere mandorle pelate, pronte per 11 con
perature) before peeling and packaging sumo, a part1re da frutti della cultivar
on the quaItty of peeled "Supernova" "Supernova" consexvatf. per tempi diver
almo~ds. The influence of the storage, sl prtma ",ella, lavoraz1one coI:1 m~sIaI1ta
teinperature after packaging was also dlfferenti (in guscl0 -a temperatura
determined. From the results of the ambiente e sgusdate a 2°C). Sulle man
chemical analyses carried out on the dorle pelate, conservate sla a tempera
lipid fraction (peroxide value, FAMEs, tura ambiente che a 2°C, sono state
spectrophotometric characteristics, -esegu1te a intervalli di 4 mesi anal1si
tocopherols), and of the physical char chim1che (numero di perossldi, indict ;
acteristics (texture, colour) and senso spettrofotometr1c1, composizione in ac1di
ry measurements, It was determined grassl e in tocoferoli). ftsiche (consi
that high quality peeled almonds can be stenza. colore) e sensor1al1. I risultati
-Key words: lipid oxidation, peeled almonds, pre-processing storage, sensory analysis. -
ltal. J. Food Sci., n. 2 -1996 115
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obtained either with nuts processed dimostrano che e possibile ottener
:., ,. immediately after harvesting. or with in mandorle pelate di buona qualita si
shell almonds stored for four months at lavorando i frnUi subito dopo la rae
ambient temperature (lBO-25°C) or with colta, sia conservandoli in guscio
. i. : ' shelled almonds stored in cold condi temperaturaQ ambiente per 4 mesi
tions (2QC) for up to eight months before sgusciati a 2 C fino a oUo mesi prim
:.::, .. .. ,::, processing. Moreover, in order to have della lavorazione. Conservando, ino]
::i.·/).~::?; e
high quality almonds up to 12 months, tre, Ie mandorle pelate a 2QC. possi
Q
it is best to store peeled nuts at 2 C. bile avere del prodottl di elevata qualit
,.. ~::;: ';>\;:,,~'. .','~> ;?o,' <._."..~
fino a 12 mesi di conservazione.
,,:
...
INIRODUCTION alliz.ed film under nitrogen and refrige
ation. Moreover, RIZZOLO et al. (l9~
To increase the sales of almond (Amyg reported that peeled almonds could'
d.alus communis) products, the quality of stored up to one year using low b~ "1
the nuts and consumer demand should packaging (polyethylene film) onI} _
be considered. Ready-to-eatalmonds, cultivar has a particularly hi@ "onte
i.e. shelled, peeled and packaged kernels, of tocopherols (natural antio~ t).
are considered a convenience food and The objective of this work wa::. op·
LO
can be consumed directly or used by up new perspectives for peeled almOl
the food industry as a semi-fmished marketing by studying i) the effects of t
product. The quality of these products storage protocol (in-shell. shelled, st(
depends on the raw material (i.e. culti age time and temperature) before peeli
var, agronomic factors, year and cli and packaging, and ti) the influence
mate), and on the storage c.ond1tlons. the storage temperature after packa
One of the most important factors caus ing.
ing quality degradation is lipid oxida
tion. Hence, any treatment that can min-
. imize this should be implemented. MATERIALS AND METHODS
It has been reported that peeled
almonds are less stable than in-shell Almonds and storage conditions
and shelled almonds (GUADAGNI et before processing
al.,1978; RIZZOLO et al., 1994), thus pro
tective techniques should be used to Fully mature, freshly harvested Supe
delay the onset of lipid oxidation (HARRIS . nova almonds, grown in the Metapon
et al., 1972). area (Matera, Basilicata, Italy), we
In a previous experiment on Ferradu divided into five lots (4 kg each), 8l
el almonds (SENESI et al., 1991). it was processed after different storage timt
found that peeled kernels could be stored on arrival at the laboratory and 4 ane
for up to nine months without a serious months after harvesting, according
loss in quality when packaged in high the sampling .scheme reported in Fig.
barrier packaging. such as flexible plas The two lots of in-shell kernels -PI4 8l
tic pouches (transparent or metallized), PIB - were stored before proces ~
regardless of the storage temperature jute bags at ambient temperature [If
Q Q
(4 C or ambient). Beyond this time, qual 25 C) for four and eight months. resp~
ity can be maintained only by using met- tively, while the other two lots of shell
116 Ital. J. Food Sci. n. 2 - 1996
,.
almonds -PS4 and PS8 -were stored in Analytical methods
! possibile ottene re net bags in a normal atmosphere cold
Ii buona qualita sia room at 2°C for four and eight months, Analyses were carried out on all the
subito dopo la rac respectively. samples at four month intervals during
landoli in guscio a the storage time. Each sample consisted
Jiente per 4 mesi 0 Processing, packaging and storage of three replicates of two pouches, each.
10 a otto mesi prima On arrival at the laboratory almonds
Conservando, inol Regardless of the pre-processing stor were analysed for chemical composition
e
elate a 2°C, possi age time, the almonds were subjected (moisture, protein, fat, alcohol-insolu
)tti di elevata qualita
to mechanical shelling, hand peeling ble solids) according to AOAC method
:onservazione.
after steam treatment (2 min at 98°C), numbers '27.005, 27.007, 27.006 and
dried with air at 55°C and pac¥aged in 32.012', respectively (AOAC, 1980). The
polyethylene film pouches (size: 215 mm 011 fraction was checked for peroxide
x 160 mm; film thickness: 25 }lm; value, acidity, spectrophotometric char
WVfR=6 g/m2 x day; aIR= 4200 mL/m2 acteristics, fatty acid methyl esters
1itrogen and refrtger x day x atm) under partial vacuum (FAME) composition, and tocopherol con
RIZZOLO et aI. (1994) I (residual pressure 600 mm Hg). All the tent. Moreover water activity (aw), colour
ed almonds could be pouches were filled with about 250 g of and texture were determined and the
-:1
ear using low barrier peeled almonds. . morphological parameters were mea
r le film) only if the I Half of each lot was stored at ambient sured on thirty nuts.
.10..• . .Jarly high content temperature (18°-2qOC) on open shelves, The oU fraction from all the samples
ural antioxidant). while the other half was stored in a nor was extracted according to AOAC method
( his work was to open mal atmosphere cold room at 2°C. The number 21.006 (AOAC, 1980), under a
es for peeled almond post-process1t1.g storage time was 12 flow of nitrogen and in the dark and
ing i) the effects of the months for PO samples, 8 months for analysed for peroxide value, acidity, spec
.1-shell, shelled, stor PS4 and PI4 samples and 4 months for trophotometric characteristics, FAME
~rature) before peeling PS8 and PI8 samples. and tocopherol composition; kernels were
ld ti) the influence of
rature after packag- ,
Samples 'PO PI4 PI8 PS4 P
Storage before
\NDMETHODS processing \ 4 8
(months) O~ / /
>rage conditions
g
PROCESSING
(shelling, peeling, packaging)
3hly harvested Super I
I I I I
wn in the Metaponto Storage after A A I \ I \ / \
dlicata, Italy), were
processing
>ts (4 kg each), and"
(months)
ferent storage times:
)oratory and 4 and 8
estlng, according to Storage A ~ A . ~ A ~ A ~ A ~
ne reported in Fig. 1. temperature
lell kernels -PI4 and
be--"e processing in - Fig. 1 -F1ow-sheet of pre-storage and post-storage treatments of almonds. A= 18°-25°C: PO= processed
almonds at harvest. P14= In-shell almonds processed after four months of pre-processing storage. PI8=
m nperature (18°
In-shell almonds processed after eight months of pre-processing storage. PS4= shelled almonds processed
'igh(m onths, respec after four months of pre-processing storage. PS8= shelled almonds processed after eight months of pre
er two lots of shelled processing storage.
( Ital. J. Food Sci. n. 2 -1996 117
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also ch~ked for specific physical index Table 1 - Analysis of almonds at time 0 before
es (colom, texture). treatments. Values are the average :t standard
deviation of 30 nuts.
Peroxide value. acidity and spec
trophotometric characteristics were
. determined according to the Italian Offi Kemellength (mm) 24.9 ±2.3
. t" width (mm) 15.3:t 1.9
' ..... . . \ cial Methods for Fats and Oils numbers thickness (mm) 7.6±1.4
C-35. C-10 and C-40 (NGD. 1976).
weight (g) 1.53 ± 0.42
FAMEs. tocopherols. colour. texture and texture (kg) 8.64
8w were measure~ according to previ a,. 0.74
ously reported methods (SENESI et al .• moisture (%) 4.31
1991). Chemical analyses were repeated fat (%d.m.) 64.5
twice. Data of peroxide value. acidity. protein (% d.m.) 17.5
FAMEs and tocopherols are all expressed A.l.S.· (% d.m.) 20.1
On oU content basts. . FAMes:
C16:0 6.82
C16:1 0.42
. Sensory analyses
C18:0 1.88
/.~ C18:1 76.44
/ The samples stored at 2°C were sub C18:2 14.33
,. jected to sensory analysts; as regards tocopherols (mg/100 g oil)
,0' the samples stored at ambtent tempera a-tocopherol 451.63
; ture. sensory analysts was performed p-tocopherol 0.93
, only on PO samples after 4 months. Sen 'ttocopherol 7.5
sory anal~ts was carried out using the UVindices:
K232 0.46
preference test (LARMOND. 1977). with a
K268 0.024
semi-traitled panel of ten members. Ran
K23211<268 19.20
domly coded samples were scored for
acidity (% oleic acid) 0.29
external colour. taste and acceptance
peroxide value 0.35
on the basis of a hedonic scale ranging colour:
from 1 (extreme dislike) to 9 (extreme L· 81.38
~e) (SE~I et al., 1991). The samples a· -0.16
were randomly offered to the tasters b· 21.14
~nce a day on two different days. hue (a·Jb·) -0.0086
Yellowness Index (VI) 37.11
Statistical methods
• A.I.S. = alcohol insoluble substances
Data were submitted to analysts of
vartance; when ANOVA results were stg
niftcant. the averages were compared by
obtained for other Italian cultlvars (POlE
Tukey's test.
SEILO et al. • 1990; MASPERI. 1988). The oil
fraction had spectrophotometric char
acteristics and FAME composition typi
RESULTS AND DISCUSSION
cal of a very good quality oU (HARRIS et aI .•
Almonds 1972; SALVO et aI .• 1986). The amount of
total tocopherols was very high (more
Table 1 shows the data of the analyses than 400 mg/100 g of oU). Significantly
of the "Supernova" almonds on arrival at higher. from 10 to 70 mg/100 g of
the laboratory. This cultivar showed a than the total· tocopherol content repol"~­
relatively high yield and a low kernel ed for other almond cultivars grown in
texture. when compared to the data Italy (SALVO et aI .• 1986; MASPERI. 1988).
118 ItaJ. J. Food Sci. n. 2 -1996
Chemical properties of lipids time, these differences in peroxide value
were less and not Significant. Comparing
Overall, the peroxide value for all the the peroxide values of the almonds after
samples in all conditions ·ranged from 4 months and 8 months, it could be
0.16 to 1.86 ffable 2), indicating the low argued that the peeling process at 4
degree of oxidation of the oil fraction. months has a stabillzing effect on the 011
PO almonds had a significantly higher fraction. This effect could be further
peroxide value after 4-8 months of stor proved by using a cold pressure extrac
age. Storing peeled kernels at 2°C tion of the almond oil to exclude any
appears to slow down the oxidati<?n, possIble influence of the solvent and
without blocking it. temperature on the lipid fraction.
tnfTluheen scteodra gthee p rpoetroocxoild bee fvoarleu per; oicne sfsaicntg, peFrqewxi, d~eu tv aslIugen iwficearnet aclhsaon gfeosu nind tbhye
after four months of storage shelled FOURIE and HASSON (1989) in almonds
almonds had the highest peroxide value, stored for 16 months at 30°C, while
while in-shell almonds had the lowest; MEHERAN and FILSOOF (1974) could not
prolonging the pre-processing storage detect changes in the peroxide value
even after 12 months of storage. All these
findings confirm the good stability of
Table 2 -Peroxide values of almonds at different almond lipIds to rancidity during storage.
temPeratures and storage times. The acidity of almonds processed on
arrival at the laboratory (pO, 0 month of
lime Storage temperature storage) was of the same order as those
months . Ambient 2"C established for almonds of other origins
(ROMOJARO et aI., 1988; GARCIA OLMEDO
PO 0 0.35 a 0.35 a and MARCOS. 1971). As for the changes of
( 4 0.61 b 0.70b acidity with storage ffable 3), PO ker
12B 0O..3575 ab O1..l1B3ac nels showed a Significant increase in
acIdity after four months of storage at
PI4 . 0 0.62 0.62b both storage temperatures. The storage
4 0.B7 0.16a temperature of the packaged kernel influ
B 0.52 0.20 a enced the acidity for PI4 and PIS sam
, ples. In fact. only PI4 stored.at ambient.
PS4 0 . '1.86 b 1.86 b temperature and PI8 stored at 2°C
4 0.99 a 0.82 a showed no signtftcant changes in acidi
B 0.47 a 0.40 a ty With the storage time. All the other
PI8 40 01..3825 ab 01..2815 ba esaxmcepplet sf oshr oPwI4ed s at osriegdn tfattc a2n°tC in, cwrehaisceh,
showed a decrease. Similar to the find
PSB 40 01..4315 ab 01..2311 ab tinhges s aofmHpAlDesO RreNa ceht eadl. h(1i9g8h0 aac,i db)i tny,o nined oi f .:," :'.
catlng that almond lipids do not under
Means followed by different letters in the same col· go noticeable lipolytic activity with stor
umn and within the same sample are sign~icantly age. However, the statistically signifi
different at the 0.01 %1 level. cant differences found could indicate
eivSnengast;m tt;Pep PmSleI4p4 ce aaarnanpddttui o PrPneSIs 88f:o ==PriSn O4-hs= eahRlnleerdoldl c 8aael mslmmsooeonndntd dhasssl m ssbtotoeonrfroederdsde a aapttt r hao2amc°reCb s i sfo r bltihype itdrhe se ta r8ruwec vtauacrltueue.a wflloyhui ncsodh mcaote u tchldhe a bbneeg geetxnsp niltanni ngthe odef Ifj..
4 and 8 months before processing. storage (0.74. Table 1). According to r
TROLLER (1989). this value makes the
Ital. J. Food Sci. n. 2 -1996 119
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Table 3 ' Acidity (% oleic acid) of almonds at dif, nificantly change with storage. The star
ferent temperatures and storage times. age temperature did not significant!:
influence the amounts and the trends c
the tocopherols.
.'\\ .. mToimnteh s AmStboireangt e temperat2u°rCe The amounts .of tocopherols founl
twelve months after harvesting. regard
PO 0 0.29 a 0.29 a less of the pre-processing storage tim
4 0.71 b 0.61 b and the storage protocol after processin~
S 0.60b 0.62b were simllar to the tocopherol conten
12 O.73b 0.6Sb found in other cultivars at harvest tim
(MASPERI. 1988). This Is an Importan
PI4 0 0.71 0.71 b
feature. as tocopherols are antioxidant
4 0.65 0.55 a
that play an important role in main
S 0.73 0.51 a
ta1n1ng the 'stability of food product
PS4 0 0.70 a 0.70 a (SCHULER. 1990). So. high content toco
4 0.71 a 0.66 a pherol almonds could be suitable fa
S 0.S1 b 1.09b long term storage as well as for indus1::ril:
purposes.
PIS 0 0.60 a 0.60 The spectrophotometric characten.._.!
4 0.75b 0.61 showed a Significant increase t "~3
PSS 0 0.52 a 0.52 a (Fig. 2A) and a significant decrem 1 th
K232jK268 ratio (Fig. 3A) for PO sample
4 1.16 b O.Mb
after four months of storage.
Means followed by different letters in the same col The storage protocol before processin
umn and within the same sample are significantly and the storage temperature influence
different at the 0.01 % level. the trend of the spectrophotometric chaJ
For Sample captions. see Table 2. acter1stics. Storing the samples at amb
ent temperature resulted in a statlsti~
Significant increase in K232; PO. PI4 an
PIS samples stored at 2°C showed
Upids susceptible to autoxidation. decrease at the end of storage, whil
There were some Significant changes PS4 and PSS samples stored at 2°C ha
in the FAME composition during storage a constant value of K232 throughot
time (Table 4), above all in the percent storage time (Fig. 2).
ages ofCIS:I, C18:2 and CI6. Decreas Regardless of the storage protoc(
es occurred only in PO. PI4 and PSS before processing and the storage ten
samples, regardless of the storage tem perature. the K232/K26S ratio (Fig. ~
perature. showed a decrease at the end of sto~
Tocopherol content decreased with in all the samples. because of an increru:
storage time (Table 5), regardless of the in K268. probably due to the appeal
storage protocol: beta-and gamma-toco anee of unsaturated ketones (ROMOJAR
pherols disappeared by the end of stor et aI •• 1988)".
age in all the samples. and alpha-toco
pherol decreased to 63.79 mg/IOO g of Physical indexes
oll after eight months for the PO sample
and to 62.09 and 59.79 mg/lOO g ofoll The most noticeable change i 1:
for samples PI4 and PS4 four months colour parameters (Table 6) was a
after storage. .As for PIS and PSS kernels. which showed a tendency to increasl
alpha-tocopherol content ranged from regardless of the storage protocol '"-efO!
50 to 56 mg/lOO g of oll and did not sig- and after processing. This tren nO!
120 ltal. J. Food Sci. n. 2 -1996
.. ,'" . ::" .~"" ",
c 'lii~~f;1~1~~~~~~~,~,{,"",-,,, .,,,"',,, ' ,'"
.v ith storage. The stor Table 4 -FAME composition of almonds at different storage temperatures and storage times .
did not significantly
LlIlts and the trends of
Storage temperature
Time Ambient 2°C
)f tocopherols found months
er harvesting. regard C16 C16:1 C18 C18:1 C18:2 C16 C16:1 C18 C18:1 C18:2
ocessing storage time
:llTlelteotriho vroitctalsoaos rcnl si aosa tar p fertatheo hnaerln rae poi trrmivlioo neccpx seooimtsdn rstaattiiaennminnngtes .tt PPOI4 18402480 6675666.......37259191549832 bc a '0000000.......44434445725302 .2212211.......00810879737684bb a 7777n778665669....,.4504462536744bbaaaa0 b0 11111114534434.......2209643O5S6483b aa b . 6565665.......79403995581402cbaabab b O000000.......3S344347O22302aa b ·2221111.......20084987755638 bc a nn778778608603.....404612658493 11111114334334.......20451631632703
SUot.y hoigf hfo coodn tpernotd touccots PS4 40 65..9355 00..4435 22..0027 n783.393 1133..6680 65..3850 00..3455ab 21..0874 7n83.192 1133..5696
~ould be suitable for 8 6.67 0.43 2.09 76.44 14.32 6.40 ll.29a 1.82 74.63 14.46
is well as for industrial PI8 0 5.78 0.42 2.09 76.24 14.90 5.78 0.42 2.09 76.24 14.90
4 6.47 0.44 2.14 76.90 14.02 6.48 0.45 1.80 n03 13.83
.om•.e itrnicc rcehaasrea citne rKts2ti3c2s PSB 40 74..0723ba 00..4313 21..1308ba 8705..7819 1124..6507ab 46..3753ba 00..3333 11..8388 7806..7113 1152..63O6ba
·. ..... cant decrease in the
c FIg. SA) for PO samples Means followed by different letters in the same column and within the same sample are significantly different at
the 0.01% level.
, of storage. For sample captions, see Table 2.
tacol before processJng
:mperature influenced
ectrophotometrtc char
g the samples at ambi
!Sulted in a statistically Table 5 -Tocopherol content (mgJ 10 0 g of 011) of almonds at different temperatures and storage times.
;e in K232; PO. PI4 and
reendd aotf 2s°toCr asgheo.w wehdi lae mTounnthe s Ambient Storage temperature 2°C
pIes stored at 2°C had alpha beta gamma alpha beta gamma
. of K232 throughout
2). PO 0 358.70 d 0.89d 6.16 c 358.7{) c O,89c 6.16d
the storage protocol 4 32O.90c 0.76c 6.56c 342.38b 0.85c 5.69c
:3 a2n/Kd 2th68e sratotiroa g(eF itge. m3-) 182 5623..7890 ab 0O..0205 ab 20..0405 ba 5536..8919 aa 00,.0280 ab 02..0000 ab
leeybe lea dkctue atteuho sente oee os nft d( haR enoO f Mia snOtpcorJ~rAea:aRgs­Oee PPSI44 4a480 433556509628,....7700759930b acab 0O00O...,.0289306962 baccb 27206.,...4015110346 cbbac 436355500568.....3751753450 abbaa 0OO00.....3028903696 bbcca 27026...2.101n0663 bbcac
8 57.45 a, 0.00 a O.OOa· 5~.na 0.00 a 0.00 a
PI8 0 55.85 a 0.18 a 2.40b 55.85 a 0.18a 2.40b
!s 4 51.78 a 0.00 a 0,00 a 53.61 a 0.00 a 0.00 a
ceable change in the PSS 40 5544..4594 aa 0O.0.205 ab 20..1050 ab 5504..0524 aa . 00..0205 ba 20..0105 ba
~r~ 'Table 6) was a·.
tl. .ency to increase. Means foRowed by different letters in the same column and within the same sample are Significantly different at
,torage protocol before the 0.01 % level.
For SarI')ple captions, see Table 2.
mg. This trend is more
(
Ita/. J. Food Sci. n. 2 -1996 121
':';--,- -:----0---
., !. ••• • .
~ .... -; ..
8~-A----------------------' 25 A
5 20
2
4 j ::
~3
~
2 ~
&
~
20
1
..
i 15
'
". .
/./ 4 1.•0. .*•.0 •.1 .4• ~ 150
.. II •
•.... //
11. 0
2&
I:
D~~~~~--~------------~ C
8~------------------------, .
5 C ...... -....... --'. .. " .....
!: =---~ I ----
'. ..
10 ..
.....
~2 ~ 5
t 0 0 2 a 0 1Z
Time (months)
o '---;0"'---"'.""'--4 .. ._,
Time (monIh8J F1g. 3 - Spectrophotometric cIiaractenstics (R=
= K232/K26S) during storage time. For captions.
F1g. 2 -Spectrophotometric charac:terfstlcs: K seeFlg.2.
during sto~c time• .~ = Processeda =al mopds at
harvest (11= PO ambient; A= PO 2°C); Processed
almonds after four mo*nt .h. s of pre-processing stor
age (0= PI4 ambient: PI4 2°C; a = PS4 ambi decrease in YI occurred for PO samples.
ent; 1\= PS4 2°C); C= Processed almonds after above all for PO kernels stored at 2°C
eight mon*th .s. of pre-processing storage (0= PIS
ambient; PIS 2°C; a = PS8 ambient: 1\= PS8 after twelve months (FIg. 4A), because of
2°C). Means followed by different letters 10 the the sIgnificant decrease in the b* value
same column and Within the same Sample are lTable 6).
slgnlflcantly different at the 0.01% level.
The storage protocol before processing
greatly influenced YI (FIg. 4B-4C): for
PI4 samples, YI signiftcantly Increased
evident in samples stored' at ambIent ,after four months of storage, while PS4
temperature. L· and b· values signifi samples showed an opposite trend. inde
cantly changed only In PO samples, .pendent of the storage temperature. By
where L· Increased and b· decreased. prolonging the storage time before pro
The Yellowness Index (YI=lOOOb· 17L·) is cessing. only PSB samples stored at
more useful for describing the colour ambient temperature showed a signIfi
changes during storage than L· and b* cant Increase In YI (Fig. 4C). So. YI and
alone (FIg. 4). a* could be useful parameters for eval
Changes In.Y I were observed for PO, uating the colour changes of peeled
PI4 and PS4 samples throughout the almonds stored In different ways befor'"
storage time, but the most noticeable and after processing.
122 ltal. J. Food Sci. n. 2 -1996
• .~. ..~., 'Io.:.{ .'';-
~U~~4~iii$,~:~~L~~~:iC<';~t;~~'1"':~;;:.J'
....;. -.
Table 6 -L*, a* and b* values of almonds at different temperatures and storage times.
Storage temperature
Time Ambient zoe
months
L' a' b' L' a' b'
PO 0 81.38 a -0.16 a 21.14 a 81.38 a -0.16 a 21.14 b
4 83.09b 0.76b 20.68 a 81.85 a O.94e 21.17 b
8 83.18 b O.79b 20:60 a 83.35 b 0.59b 20.80 b
12 82.91 b 0.80b 20.35 a 84.12 b O.43b 19.21 a
PI4 0 84.03 b 0.46 a 19.47 a 84.03b 0.46 a 19.47 a
4 82.94 a 0.71 b 20.32 b 82.89 a O.69b 21.11 b
8 82.76 a 1.00 e 20.03ab 82.87 a 0.34 a 21.02 b
PS4 0 83.31 a 0.36 a 20.85b 83.31 b 0.36 a 20.85b
4 83.60 a 0.71 b 19.67 a 83.78b O.64b 20.09 a
8 83.06 a 1.08 e 20.42 ab 82.59 a 0.79 b 20.28ab
PI8 0 83.02 a 0.52 a 20.68 b 83.02 a 0.52 a 20.68 a
4 83.41 a 0.75b 19.82 a 82.45 a 0.46 a 20.28 a
PS8 0 83.S8b 0.51 a 20.58 a 83.58b 0.51 b 20.58 a
4 82.48 a 0.93b 19.96 a 82.93 a 0.33 a 21.07 a
~
-----
Means followed by different letters in the same column and within the same sample are significantly different at
the 0.01 % level.
For sample captions, see Table 2.
10 12
t4
~~--a--..:-:.-.:.-----.- --: -----h- _-__-_ -"'- ----.-..-. ~ It.
t2
~ter1stics (R= as A ._-._- • to .
"or captions, .
~80 II ••.. ·.•. • : .
..
) samples, 2 • 8 ....
:-ed at 2°C ~~~----~--~--~--~--~ 0
lbe ebc*a uvsaelu oef 8~5~ -B-...- . ,,;-,:;,:-:;:~.-- ....-•..... --..- ------=-.-..--.-.-. ..-...-I...: ---.--.- -- ---.~.-. ~ '''240• ..:.. ..:
processing 5f80 0* .OA. .. 11 • 4 0•1 .*•. r.•n. A.•
B-4C): for \ 26 4 •. . II .. ... 4 • • .. II
increased ~L-__~ _________1_2_ ._. _.. _____~ 2 12.
while PS4 \ ,
0..
rend, inde ~r--------------------------.
rature. By as ~.~.-.... ~. ...... _.. ..... ~.~..... .. -...::;t 12
>efore pro- 5 to
s+-~ed at II 8
i. .gnIfi e.. •• ••••
• ••••
So, YI and
2
's for eva!-
0
of peeled
Time (mon1tla)
( ·ays before
Fig. 4 -Yellowness Index (YIJ dUring storage time. FIg. 5. Texture (kg) during IItorage time. For cap
For captions. see Fig. 2. tions. see FIg. 2.
.
',,;, ~, '
., . . -.,'
,. ' .'.'... ......~ .
. .- ..... ..........- .
.' ',.' ' !.' " !':':~-' '
-(
:. "'.~." :.
"
f \ Po ;,., dr;:;~\~ € ~\ft";;~';ii,~
,.~. ~. ,;' .j.~-..:.~;;~.~.: .. ~ ... ~i.' " '" . ',' .
Tmaobnlet h7s - oSfe sntosoraryg ea.n alysis: scores after 4. 8 and 12 tthheeA lffaottertmre rte wbr.ee ilnvge rmatoedn tshlisg hotfly s bt9ertategre t,h aPOn
Colour Taste Acceptance scaomlopulre, sa nredc PeIi vseadm tphlee sh wigehree sjut dsgcoedre b feotr
" ,'. 4P2O" mC a omnbthiesn.t 66..3124 66..2614 66..5000 ttefeiinmdrc eetenh sot,alf yna pa lrclPo ctSche eepss tassamiabnmlpgel.p,e Dlwse,esi ts rhwpe gitethareeer td jehulxeedcssgesepe dotdiifo 'f sftnueh rfoe f
8 months (2°C) . sample PS8, which was rated negative-
PPPOIS4 4 756...270339 baa b 655...708346 abab 655...807203 bab loyr gTfoahrn eota lesbpteeti tact necdrh aamrcacacetipenrttaiesntncicaes.n ocbes eorvfe . dt-h i,n~ \
1PPPP2O1SIS4 m4' onths (rC) 6655....83870500 5656....07070050 aaaabb .5656....70715555 aaaabb P1h(p2Onar°go rCs vteoa)fe cmfsesotcptliot nlb eargeacs f hgaocienroee.duv p Alefdrdoso lb bclroeeyew s dgsseutiadener agd btm,so yt h pttrhheeeee efsrl tsiiosngtatrgeoba ragrUaafetitge zeode-rf \ \ \~ \
PS8 5.75 4.70b 4.85b in-shell almonds at ambient tempera- I
Mumeann asn fdo lwloiwtheind tbhye dsiaffmeree nsta lmetptelers a irne tshieg nsiaflCmael ltclyo ld-if- ttpuhrroaebn a sbreeleyfrm tihgsee r taaoltm iooofnfn edor f s mhsheolerlle il tesaded lvaf lcamonuotalndgd besse; .{.
fFFeoorerr nsstca aamlte pt,hl ese e c0ea. 0pM1ti oa%ntes lre,i avsleesl e.a nTda bMlee 2th. ods section. 1anng e ofxfeidcatitvive en daettuerraiol rpaaticokna dguer iinn gp rsetovreangte- \I!
at 18°-25°C.
/ """i
CONCWSIONS·
ctilsfasnunyeottnoorTc sraehd rs rPnhea,eii vPnetg5gat ioS ogesh4dsoiSv; e ehn st e rtno(asgahr Fcmrav dttieeamgrha pgse.stle plohnuea5e lsmda m)eset;tt, .osre e P atTre r O reefiabaehtnx ageestmeftcehmarul th u aampreeeiVieeenxnipnn rgiwgtelioctuheo d aeaurbtsd srea ose. sm wl iaonTfhmgfoaof ohfnt roePsnwhteecfsI treft e4tthecoep d,ct sa duwer Po na onxbIoantn Sd ys f addrlp"dlialiaSupaimpTttdueiceiiddoh p okdnts neeonfa o.frdr gatnIatlsa nhtiuico tpnnste vnyfihidg aaod dhaoc " ne ict wut-rgahf,ifg sdrlehoiimeoas dn urtd c aon otgsfth tdcnepriiieo oedaonii tapnstnm eout h t s "forrhooetF etedorfifhe sois rt fecir"eh lsiro- Sdecae"tpuaa xdSu aoltlnuopuptidlcoe wpyee 1elnwerur "8 bsinrt n°emp onao-osle o2rlafoveer 5v ttxbnialu°haeei"Cet " der,
\ storage temperature. kernels packaged in high barrier film
pouches and s~ored both at ambient
Sensoxy analysis temperature and 4°C in a previous stor
7cprpat)ahhlga Teteearegsmh,and emeaP i na cfPOreeatseI etrl 4ssae araau cr lnafmsclloty.dne spu pA d palrot ef hagfPtmsby etr Shlsreroe i4eeeec,nc diasitfeg. lehoei whnavs.r t sn e6i ooamtda.hlx1fl loy h y4 stsnip -tthgeo6teashehr.sr.6a sea tP4gds rmoO, easr f ef rctsw osataoartebe omrraorlerseel f s,l apmatpeghecreaeIeeacetn l toletcee ieournuddisrngl a tdtast l ia e(t,lvaS omrtrat Er ethhroaoN: aenc g Eahrh de)vSaao ate!vpss hnsepeeaett dencia acnk;t c olhtag.b)sc, ig) w fgo 1eotihp9omhdlhl9 qe'o m1ebiunwnr)eae o et ldlhldito tia ecywabk o,tp yenebrs nttorsaeoect rfnreierrentaisi deto~m~o,rrf
•• ~. , C,.,rvI.~; n ? - 1996