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Three hundred consumers were required to mix a hot and a cooler coffee together until it was at a desired temperature for drinking. They added creamer and sweetener to taste. In a 2nd experiment, 108 consumers performed the same experiment with black coffee only, but repeated it using different coffee strengths. In all experiments, the chosen mean preferred temperature for drinking was around 60 °C (140 °F). Black coffee drinkers chose a slightly higher mean temperature than drinkers with added creamer, and they also chose a slightly lower mean temperature when the flavor was stronger. In all cases, consumers tended to choose, on average, temperatures for drinking coffee that were above the oral pain threshold and the burn damage threshold.
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2774 JOURNAL OF FOOD SCIENCE—Vol. 67, Nr. 7, 2002 © 2002 Institute of Food Technologists
Sensory and Nutritive Qualities of Food
JFS: Sensory and Nutritive Qualities of Food
At What Temperatures Do Consumers Like to
Drink Coffee?: Mixing Methods
ABSTRACT: Three hundred consumers were required to mix a hot and a cooler coffee together until it was at a
desired temperature for drinking. They added creamer and sweetener to taste. In a 2nd experiment, 108 consumers
performed the same experiment with black coffee only, but repeated it using different coffee strengths. In all
experiments, the chosen mean preferred temperature for drinking was around 60 °C (140 °F). Black coffee drink-
ers chose a slightly higher mean temperature than drinkers with added creamer, and they also chose a slightly
lower mean temperature when the flavor was stronger. In all cases, consumers tended to choose, on average,
temperatures for drinking coffee that were above the oral pain threshold and the burn damage threshold.
Keywords: coffee, drink temperature, oral pain threshold
amount of litigation resulting from cof-
fee spills in restaurants and other places
serving coffee; such cases rest on the sup-
position that coffee is served at a temper-
ature that is so high that its risks outweigh
its benefits (Borchgrevink and others
1999). It is thus important to investigate
temperatures at which consumers prefer
to drink their coffee and the relationship
of these temperatures to those that inflict
pain or skin damage.
For coffee, the standard holding tem-
perature, established by the Coffee Brew-
ing Center (U.S.A.) and the Nordic Coffee
Center (Norway) ranges 80 to 85 °C (176 to
185 °F) (Lingle 1996). However, in reality,
serving temperatures might range from
around 71 °C to above 85 °C (160 to above
185 °F) (Lingle 2000). Borchgrevink and
others (1999) report that the hospitality
literature recommends holding tempera-
tures in the range 85 to 88 °C (185 to
190 °F). Such temperatures are higher
than reported pain or epithelial damage
thresholds in the literature.
There have been relatively few studies
on pain thresholds in the mouth. Yamada
and others (1952) mapped the mouth for
spots sensitive to pain, using Miller’s den-
tal broach. Svensson and others (1992)
measured pain thresholds induced by ar-
gon laser stimulation. For thermal pain,
Green (1985) measured mean thresholds
on the dorsal surface of the tongue
(47.8 °C, 118 °F) and the inner wall of the
lower lip (47.5 °C, 11.7.5 °F) with an as-
cending series method. Margarida and
others (1962) measured mean thresholds
on the hard palate, ranging from 46.2 to
47.0 °C (115 to 116.7 °F), using the method
of constant stimuli. Pain thresholds for
coffee may be inferred from these data,
with the caveat that the thresholds were
measured using a thermode stimulator
rather than a mouthful of hot coffee and
that both threshold methods used single
stimulus presentation, which is prone to
response bias from -criterion variation
(O’Mahony 1992).
These oral cavity thresholds were gen-
erally higher than thresholds quoted for
other parts of the body. Green (1985)
made within subjects’ comparisons with
the vermilion border of the lower lip
(46.0 °C, 114.8 °F) and the middle of the
chin (46.3 °C, 115.3 °F). Hardy and others
(1952) quoted thermal pain thresholds all
over the body surface ranging from
45.7 °C (114.3 °F) on the forehead to
42.2 °C (108 °F) on the lower back; this ex-
cludes a higher threshold noted for an
area of calloused skin on the heel. Stoll
and Greene (1959) noted a pain threshold
on the ventral surface of the forearm of
43.2 °C (109.8 °F).
There have not been any studies re-
garding heat damage to the surfaces of
the inside of the mouth, so inferences
must be made from data obtained from
skin on other parts of the body. The extent
of burn damage to the skin depends not
only on the temperature, but also on the
time that the thermal stimulus is present,
as well as the thickness of the skin in-
volved (Johnson and others 1981); this
has been modeled (Buettner 1951; Enale-
jev and Kachalkin 1998; Stoll and Greene
1959). Katcher (1981) has reviewed adult
skin burns drawing on the data of Moritz
and Henriques (1947), who measured
times required to cause complete destruc-
tion of the epidermis on the chest and the
ventral surface of the forearm at various
temperatures. They quote 1 sec at 70 °C
(158 °F), 2 sec at 65.6 °C (150 °F) and 5 sec
at 60 °C (140 °F). These are realistic values
for the time hot coffee may be held in the
mouth. For longer periods of time, lower
temperatures will inflict similar damage
(for example, 30 sec at 54.4 °C (129.9 °F) or
10 min at 48.9 °C (120 °F)), but these data
are not so relevant for drinking coffee.
Stoll and Greene (1959) noted blister for-
mation on the ventral surface of the fore-
arm with a 7.8 sec exposure at 56.7 °C
(130.1 °F). There are also several case
studies where patients have suffered
burns from ingesting hot liquids; the dan-
ger is that the resultant scalding can block
the airways, and, in one case, this ended
in death (Sando and others 1984; Kulick
and others 1988; Cooper and others 1990;
Dye and others 1990; Mellen and others
Thus, from the literature, it would
seem that the normal and recommended
temperatures at which coffee is held for
serving are not only above reported pain
thresholds but also above possible dam-
age thresholds in the mouth. The issue
becomes a question of whether consum-
ers really prefer to drink their coffee at
such high temperatures or whether they
would prefer lower ‘safer’ temperatures.
Borchgrevink and others (1999) stated
rather disturbingly that “…it would ap-
pear that temperatures specified as rec-
ommended temperatures by the hospital-
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Vol. 67, Nr. 7, 2002
Sensory and Nutritive Qualities of Food
Consumer coffee temperature preference . . .
ity and food literatures for brewing and
holding coffee are at odds with the medi-
cal literatures discussion of beverage tem-
peratures that result in burns, permanent
damage, and death. They used a 5-point
just right scale to assess liking for various
temperatures of black coffee. They quoted
the ideal temperature for serving being
between 62.8 to 68.3 °C (145 to 155 °F),
these being the temperatures closest to
the ideal score of 3 on their 5-point scale.
Unaware of their research, Pipatsattay-
anuwong and others (2001) used an R-in-
dex ranking task to determine preferred
temperatures for drinking. The most pre-
ferred temperature was 72.1 °C (161.8 °F)
followed by 60.9 °C (141.7 °F) followed by
76.6 °C (169.8 °F). The least preferred
temperature was 39.2 °C (102.5 °F), the
only temperature in the study that was
below the pain and damage thresholds.
The goal of the present study was to ex-
tend this research by examining preferred
drinking temperatures, not only for black
coffee, but also for coffee with added
creamer. The approach was to present
consumers with a source of hot coffee and
of cooler coffee that could be mixed ad-lib,
until the preferred temperature was at-
tained. This was then measured immedi-
ately with a fast thermocouple. During the
mixing process, creamers and sweeteners
could be added to taste. In Experiment I,
preferred drinking temperatures were
measured for both black coffee and coffee
with added creamer. In Experiment II, the
effect of coffee strength was investigated.
Consistency checks were made in both ex-
Materials and Methods
Experiment I. Three hundred consum-
ers (121 M, 179 F, 18 to 63 y), students,
staff, and friends were sampled from the
Univ. of California, Davis, Calif., U.S.A.
campus. Of these, 107 (49 M, 58 F, 18 to 63
y) consumers reported drinking coffee
once a d or more, 116 (49 M, 67 F, 18 to 52 y)
once a wk or more, 77 (23 M, 54 F, 18 to 44
y) once a mo or more.
Experiment II. One hundred and eight
consumers (54 M, 54 F, 18 to 55 y) were
sampled as in Experiment I; 30 (15 M, 15 F,
18 to 53 y) reported that they drank coffee
once a d or more, 48 (24 M, 24 F, 18 to 53 y)
once a wk or more, 30 (15 M, 15 F, 18 to 55
y) once a mo or more.
Coffee Preparation
Experiment I. Folgers Gourmet Su-
preme coffee (The Folger Coffee Co., Cin-
cinnati, Ohio, U.S.A.) was prepared from a
single brewer (Bunn Single SH: Bunn-O-
Matic Corp., Springfield, Ill., U.S.A.). The
brewer delivered hot water to the coffee
(240gm) in a filter (Bunn Gourmet Coffee:
Bunn-O-Matic Corp., Springfield, Ill.,
U.S.A.) at temperatures ranging from 82.1
to 91.4 °C (179.8 to 196.5 °F). Coffee was
later transferred to 2 servers (Bunn-O-
Matic SH Server, Thermofresh: 1.5 gall ca-
pacity, Bunn-O-Matic Corp., Springfield,
Ill., U.S.A.).
Once the coffee had been brewed, and
before transfer to the servers, it was trans-
ferred to a stainless steel container. More
water was added through the coffee filter
to adjust the volume to a standard
amount, to give a strength of 42.3 gm/ L
(160 gm/ gal). This was because the coffee
brewer did not deliver a sufficient volume
of coffee each time, while it also varied in
the amount it delivered. Having adjusted
the volume, the coffee was delivered to
the servers. For the coffee that was served
at the cooler temperature, the stainless
steel container was kept in an ice bath. Af-
ter adjustment, the coffee was placed in a
server which was switched off and deliv-
ered coffee at approx. room temperature.
For the coffee that was served hot, the
stainless steel container was sometimes
warmed when necessary, before transfer
of the coffee to the server. To enable the
experimenter to test for a longer period of
time, 2 cooler and 2 hot servers were pre-
The temperature of the coffee in the
servers was measured by thermocouple
(Mini-Alarm Thermometer with Probe,
Control Co., Friendswood, Tex., U.S.A.). In
the cooler servers, which were switched
off, the temperature of the coffee ranged
21.1 to 23.8 °C (70 to 75 °F); in the hot serv-
ers, the temperature ranged 85.0 to
90.6 °C (185 to 195 °F).
Also available for adding to the coffee
was a selection of creamers and sweeten-
ers. The sweeteners available were: white
sugar (C&H Pure Cane Sugar; C&H Co,
Crockett, Calif., U.S.A.), brown sugar
(Light Brown Sugar; I.G.A. Inc., Chicago,
Ill., U.S.A.), saccharin (SweetnLow; Cum-
berland Packing Corp. Brooklyn, N.Y.,
U.S.A.), and aspartame (Equal; The Nu-
trasweet Co, Chicago, Ill., U.S.A.). The
creamers were: Nestlé Carnation Coffee
Mate (Nestlé USA, Glendale, Calif.,
U.S.A.), non-fat milk (Crystal Cream &
Butter Co. Sacramento, Calif., U.S.A.) and
half and half (Crystal Cream & Butter Co.
Sacramento, Calif., U.S.A.). To keep them
cool, the milk and the half and half were
served in thermos flasks (Thermos Coffee
Butler; Canadian Thermos Products Inc.,
Scarborough, Ontario, Can.). Stirrers
(Happy Time Drinking Straws; Blue Dia-
mond Straw Inc., Los Angeles, Calif.,
U.S.A.) were also provided.
Experiment II. Coffee preparation was
as in Experiment I, with the modification
that 1 pair (hot and cool) of servers had
the same strength of coffee used in Exper-
iment I (42.3 gm/L) while the other pair
had stronger coffee: 66.9 gm/ L (253 gm/
gal). The cooler servers were again
switched off and contained coffee at tem-
peratures ranging 25.3 to 32.2 °C (77.5 to
90.0 °F). The temperature of the coffee in
the hot servers ranged 83.0 to 92.7 °C
(181.4 to 199.0 °F). Here the coffee was
served black.
Coffee Tasting
Experiment I. After interception, con-
sumers were screened; demographic de-
tails were collected, and instructions were
given. During this time, care was taken to
establish rapport with the consumer. The
exact instructions given depended on the
personality of the consumer but were gen-
erally as follows:
This is an experiment to see at what
temperature you like to drink your coffee.
This pot (indicating hot server) contains
hot coffee; this pot (indicating cooler serv-
er) contains cold. (Experimenter pours a
little hot coffee, approx. 30mL into the cup
and presents it to the consumer). You can
take the hot coffee and add as much cold
coffee or milk as you wish to cool it down to
the temperature you like. If it is too cold,
you can add hot coffee to warm it up
again. You can add as much sweetener and
creamer (indicating sweeteners and
creamers) as you wish. Just make the cof-
fee the way you usually do. When the tem-
perature is just right for you, let me know
and I will quickly measure it.
Care was taken to ensure that the con-
sumer understood the task completely.
Consumers were allowed to respond that
even the hot coffee was too cool, but none
did. Consumers dispensed hot and cold
coffee into an expanded polystyrene cup
(J Cup, 8oz, Dart Container Corp., Mason,
Mich., U.S.A.). Expanded polystyrene was
used for its insulating properties, because
judges were required to judge the temper-
ature of the coffee by using thermo-recep-
tors in the mouth, with minimum interfer-
ence from receptors in the hand. Once the
consumer had mixed his coffee, the tem-
perature was measured using a fast re-
sponding thermocouple (Physitemp,
Model BAT-12: Physitemp Instruments
Inc. Clifton, N.J., U.S.A.).
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Sensory and Nutritive Qualities of Food
2776 JOURNAL OF FOOD SCIENCEVol. 67, Nr. 7, 2002
Consumer coffee temperature preference . . .
From this group of 300 consumers, 33
consumers were chosen to measure con-
sistency. They returned a further 9 times,
giving each one a total of 10 sessions, all
on different d. Of the 33 consumers, 12 (7
M, 5 F, 18 to 31 y) drank coffee at least once
a d, 10 (6 M, 4 F, 19 to 26 y) at least once a
wk, and 11 (3 M, 8 F, 18 to 26 y) at least
once a mo. Session lengths ranged 1 to 8
min. Room temperature ranged from 20.0
to 27.1 °C (68.0 to 80.8 °F).
Experiment II. The procedure was as
for Experiment I, except that only black
coffee was served and all consumers per-
formed the experiment 3 times, at least 1 d
apart. On 1 d, the consumer performed
the experiment with the weaker strength
coffee. On another d, he performed it with
the stronger coffee. On a 3rd d, as a consis-
tency check, half the consumers used the
stronger coffee and half the weaker coffee.
The order of these 3 conditions was coun-
terbalanced over consumers. Session
lengths ranged from 1 to 5 min. Room tem-
perature ranged from 20.4 to 25.7 °C (68.7
to 78.3 °F).
Results and Discussion
ferred temperatures for drinking the
coffee in Experiments I and II. For the 300
consumers tested in Experiment I, the
mean chosen preferred temperature was
59.8 °C (139.6 °F). The median (59.5 °C,
139.1 °F) was close to the mean, suggest-
ing a symmetrical distribution.
For the 102 consumers who drank their
coffee black, the mean chosen preferred
temperature was 61.5 °C (142.7 °F), while
for the 198 who drank their coffee with
added creamer, the mean chosen pre-
ferred temperature was 59.0 °C (138.2 °F).
There was a slight yet significant differ-
ence between the means of the 2 groups
(independent samples t-test, 2-tailed,
p0.02): the black coffee group tended
to choose a higher temperature.
The consistency of the 33 consumers
who performed the experiment 10 times
was examined. Over the ten sessions, the
temperature chosen for drinking varied
considerably for a given consumer. The
mean range of variation over the consum-
ers was 12.0 °C (21.6 °F). The largest varia-
tion for a single consumer was 32.7 °C
(58.9 °F); the smallest was 4.8 °C (8.6 °F).
This puts into perspective the difference
between the mean most chosen tempera-
tures for consumers drinking black coffee
versus coffee with added creamer. It also
indicates that consumers do not have a
specific preferred temperature but rather
a preferred range of temperatures.
In passing, it is worth noting that the
mean variation for the subgroups within
the 33 consumers, varies with the fre-
quency of drinking coffee. For the 12 con-
sumers who drank coffee at least once a d,
the mean variation was 9.6 °C (49.3 °F).
For the 10 who drank coffee at least once a
wk, the mean was 11.6 °C (52.9 °F) while
for the 11 who drank coffee at least once a
mo, it was 14.8 °C (58.6 °F). The difference
between the 2 most extreme groups was
significant (ANOVA, LSD, p 0.05); be-
tween others it was not (p 0.2). This indi-
cated that there was a trend for more fre-
quent drinkers to have less variation in
their choice of preferred temperature.
Experiment II. Some consumers per-
formed the test twice with stronger coffee
and once with weaker coffee, while others
performed it twice with weaker coffee and
once with stronger. Comparisons were
made between temperatures chosen in
successive sessions for stronger compared
with weaker coffees, to see the effect of
coffee strength on chosen temperature.
Comparisons were also made between
temperatures chosen in successive ses-
sions for stronger compared with stronger
or weaker compared with weaker coffees
to check consistency.
From Table 1, for the 108 consumers,
the mean chosen preferred temperature
for stronger coffee was 59.3 °C (138.7 °F),
while for the weaker coffee, the mean tem-
perature was 60.4 °C (140.7 °F). The small
difference between the means was signifi-
cant (t-test, p 0.01). Bearing in mind the
variation for the individual consumers
noted in Experiment I, significance was
more likely to indicate the large sample
size rather than a large effect.
As a consistency check, comparisons
were made between the chosen tempera-
ture in 2 successive sessions using weaker
coffee and 2 successive sessions using
stronger coffee. These 2 conditions were
combined to gain statistical power. Thus,
for all 108 consumers, the mean chosen
preferred temperature in the 1st of the 2
like sessions was 60.6 °C (141.1 °F;
SD = 6.4 °C, 11.5 °F). For the 2nd like ses-
sion, the mean was 59.2 °C (138.6 °F;
SD 6.9 °C, 12.4 °F). This difference was
not significant (t-test, p 0.14), which in-
dicated that the difference between stron-
ger and weaker coffee was a consequence
of coffee strength.
The mean chosen preferred tempera-
ture for both black coffee and coffee with
added creamer for the 300 consumers
tested in Experiment I (59.8 °C) was lower
than the preferred temperature (72.1 °C)
found by Pipatsattayanuwong and others
(2001). It was closer to the 2nd most pre-
ferred temperature (60.9 °C). However,
despite the fact that both studies brewed
their coffee to the same strength, the com-
parison is not justified. This is because the
present study included coffee with cream-
er while the previous study did not. Con-
sidering only the 102 consumers who
drank their coffee black, in the present
study, the mean chosen preferred temper-
ature of 61.5 °C was still lower than the Pi-
patsattayanuwong and others study.
There is a further difference between
the 2 studies. In the Pipatsattayanuwong
and others study, the consumers made
their judgments by taking small sips of the
coffee. In the present study, consumers
adjusted the coffee temperature to be
suitable for drinking larger mouthfulls.
Thus, it is possible that the consumers
were more cautious and chose slightly low-
er temperatures for the present study.
Yet, the comparison between the 2
studies is put into perspective by the con-
sistency study, which indicated that when
Table 1—Preferred temperatures for drinking coffee, determined by a mixing
method used in Experiments I and II
Number of Mean Standard
Consumers Comments Temperature Deviation Range
Experiment I
102 drinking 61.5 °C9.1 °C 36.7 to 88.0 °C
black coffee (142.7 °F) (16.4 °F) (98.1 to 190.4 °F)
198 drinking coffee 59.0 °C7.5 °C 41.6 to 83.8 °C
with creamer (138.2 °F) (13.5 °F) (106.9 to 182.8 °F)
and/or sweetener
300 total 59.8 °C8.1 °C 36.7 to 88.0 °C
(102 + 198) (139.6 °F) (14.6 °F) (98.1 to 190.4 °F)
Experiment II
108 stronger 59.3 °C 6.5 °C 41.0 to 72.4 °C
black coffee (138.7 °F) (11.7 °F) (105.8 to 162.3 °F)
weaker 60.4 °C 6.7 °C 41.9 to 78.5 °C
black coffee (140.7 °F) (12.1 °F) (107.4 to 173.3 °F)
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Vol. 67, Nr. 7, 2002
Sensory and Nutritive Qualities of Food
Consumer coffee temperature preference . . .
the experiment was performed ten times,
there was considerable variation in the
preferred temperatures chosen. The dif-
ferences between the temperatures cho-
sen in the Pipatsattayanuwong and others
study and the present study (13.6 °C) are
comparable to the mean variation noted
in the consistency study (12 °C).
The consistency study also indicated
that consumers did not have a specific
preferred temperature at which they
chose to drink their coffee. Rather, they
had a range of temperatures that were
deemed suitable. It was also worth noting
that consumers who drank coffee more
regularly tended to vary less in their
choice of preferred temperature.
Borchgrevink and others (1999) report-
ed the ideal temperature for serving being
between 62.8 to 68.3 °C, which again is
slightly higher than in the present study.
It is not totally clear whether their judges
sipped small volumes or drank larger
mouthfuls of coffee. If the former was the
case, then the same hypothesis would ap-
ply to these differences as applied to the
differences found by Pipatsattayanuwong
and others (2001).
It is also possible that Borchgrevink
and others (1999) brewed their coffee at a
different strength. In Experiment II, it
was found that the preferred tempera-
ture for drinking coffee was less when the
coffee was stronger (59.3 compared with
60.4 °C). Although this small difference
was significant and greater than the con-
trol differences found in Experiment IIs
consistency check, it was still small com-
pared to the variation of individual con-
sumers found in Experiment I. Yet, the re-
sults suggest the hypothesis that the
consumers might be optimizing their
stimulation from the coffee, by increas-
ing the temperature stimulation when
the flavor stimulation is reduced. Howev-
er, pursuit of this line of argument could
give surprising conclusions. Experiment I
indicated that consumers who drank
their coffee black had a higher mean cho-
sen preferred temperature (61.5 °C) than
those who drank coffee with added
creamer (59.0 °C). From this it could be
inferred that coffee with creamer had a
stronger flavor than black coffee. This
would seem to be counterintuitive. How-
ever, there is a confounding factor; con-
sumers who used creamer had a signifi-
cantly greater tendency than black coffee
drinkers to use a sweetener (chi-squared,
p0.001). It could then be argued that
the added sweetener provided the stron-
ger flavor.
ments I and II were very close. They
tended to be slightly lower than tempera-
tures found by Borchgrevink and others
(1999) and Pipatsattayanuwong and oth-
ers (2001). Yet, the same conclusion can be
drawn from all these studies, that con-
sumers tended to choose on average, tem-
peratures for drinking coffee that were
above those published for oral pain and
epithelial burn damage thresholds. This
poses the question as to why consumers
do not burn their mouth while drinking
coffee at their preferred temperatures.
This is currently under investigation.
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MS 20010590 Submitted 10/20/01, Accepted 4/3/02,
Received 4/8/02
This research was supported by a grant from the Specialty
Coffee Association of America. The authors would like to
thank Ted Lingle for his advice and help.
Author O’Mahony is with the Dept. Food Science &
Technology, Univ. of California, Davis, CA 95616,
U.S.A. Direct inquiries to author O’Mahony (E-mail:,
jfsv67n7p2774-2777ms20010590-WA.p65 9/20/2002, 3:06 PM2777
... The infusion was prepared with 4.5 g per 100 mL of water in glass French presses with purified water, heated at 96°C, and then, left to rest (5 min); 35 mL of coffee solution was served in 100 mL white ceramic cups coded with random three-digit numbers, at 68 ± 2°C. 22,23 Instant coffee was prepared according to the manufacturer's recommendations (2 g 0.15 L −1 hot water). ...
Background In Mexico, the coffee activity is mainly carried out in indigenous zones, involving almost one million people. However, local national coffee consumption is low. This article focuses on the analysis of the effect of consumers’ expectations as well as some sociodemographic characteristics on the level of liking of Mexican local coffee. Four coffees from three indigenous zones of Hidalgo, Mexico were evaluated using a 9‐point hedonic scale. The samples were evaluated under three conditions: a) blind, no information given to the consumer; b) expected, only information given to the consumer; and c) informed, giving information and product to the consumer. Results The difference observed between expected and blind condition was significant (p < 0.005) for the three local coffees evaluated, indicating a negative disconfirmation. The local coffees were less appreciated than expected, since the information about the samples created high hedonic expectations among the consumers. The level of education and the place of residence of consumers had a significant influence on their level of liking. Based on demographic characteristics, three segments were found presenting a different pattern of liking. Conclusions Consumers had positive expectations towards the local coffee. The sociodemographic characteristics and aspects related to consumption, particularly the experience with the product, are decisive in the expectations concerning the local product. This investigation can be useful to generate marketing strategies according to the demands and needs of the market, making local products to be valued. This article is protected by copyright. All rights reserved.
... Interestingly, it has been reported by several studies that the most preferred or recommended drinking temperatures of black coffee are often well below the mean serving temperatures encountered in the two mentioned studied (~75 • C), for instance (decimals were rounded to the near whole number), 68 • C [24], 72 • C [25], 60 • C [26], 58 • C [27] and 63 • C [28]. ...
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The International Agency for Research on Cancer has classified the consumption of “very hot” beverages (temperature >65 °C) as “probably carcinogenic to humans”, but there is no information regarding the serving temperature of Brazil’s most consumed hot beverage—coffee. The serving temperatures of best-selling coffee beverages in 50 low-cost food service establishments (LCFS) and 50 coffee shops (CS) were studied. The bestsellers in the LCFS were dominated by 50 mL shots of sweetened black coffee served in disposable polystyrene (PS) cups from thermos flasks. In the CS, 50 mL shots of freshly brewed espresso served in porcelain cups were the dominant beverage. The serving temperatures of all beverages were on average 90% and 68% above 65 °C in the LCFS and CS, respectively (P95 and median value of measurements: 77 and 70 °C, LCFS; 75 and 69 °C, CS). Furthermore, the cooling periods of hot water systems (50 mL at 75 °C and 69 °C in porcelain cups; 50 mL at 77 °C and 70 °C in PS cups) to 65 °C were investigated. When median temperatures of the best-selling coffees are considered, consumers should allow a minimum cooling time before drinking of about 2 min at both LCFS and CS.
... Significant interactions between the consumption temperature and the coffee samples for characteristics such as coffee fullness, fidelity, and balance suggested that sample combinations should be considered when developing hot coffee flavor profiles. These findings supported earlier claims by Lee and O'Mahony [138] that consumers preferred drinking coffee at about 60 °C regardless of whether it was black or contained added additives such as creamer and sweetener. ...
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Flavor continues to be a driving force for coffee’s continued growth in the beverage market today. Studies have identified the sensory aspects and volatile and non-volatile compounds that characterize the flavor of different coffees. This review discusses aspects that influence coffee drinking and aspects such as environment, processing, and preparation that influence flavor. This summary of research studies employed sensory analysis (either descriptive and discrimination testing and or consumer testing) and chemical analysis to determine the impact aspects on coffee flavor.
... Their ingestion and preferences with respect to temperature have established a predilection for warm beverages between 55°and 70°C and even up to 78.5°C (2). Hot fluid ingestion has been associated with a potential increase in cancer, leading the International Agency for Research on Cancer to classify hot fluids (>65°C) as probably carcinogenic to humans (3); however, temperatures between 55°and 65°C have been identified as an ideal temperature range associated with a satisfactory sensation to the consumer without burning and harmful effects (4,5). Although considerable work has been undertaken to understand the potential carcinogenic effects of the ingestion of hot fluids, less is understood about the dynamics of heat dissipation of warm fluids (≤55°C) throughout the esophagus and stomach. ...
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We hypothesized that ingested warm fluids could act as triggers for biomedical devices. We investigated heat dissipation throughout the upper gastrointestinal (GI) tract by administering warm (55°C) water to pigs and identified two zones in which thermal actuation could be applied: esophageal (actuation through warm water ingestion) and extra-esophageal (protected from ingestion of warm liquids and actuatable by endoscopically administered warm fluids). Inspired by a blooming flower, we developed a capsule-sized esophageal system that deploys using elastomeric elements and then recovers its original shape in response to thermal triggering of shape-memory nitinol springs by ingestion of warm water. Degradable millineedles incorporated into the system could deliver model molecules to the esophagus. For the extra-esophageal compartment, we developed a highly flexible macrostructure (mechanical metamaterial) that deforms into a cylindrical shape to safely pass through the esophagus and deploys into a fenestrated spherical shape in the stomach, capable of residing safely in the gastric cavity for weeks. The macrostructure uses thermoresponsive elements that dissociate when triggered with the endoscopic application of warm (55°C) water, allowing safe passage of the components through the GI tract. Our gastric-resident platform acts as a gram-level long-lasting drug delivery dosage form, releasing small-molecule drugs for 2 weeks. We anticipate that temperature-triggered systems could usher the development of the next generation of stents, drug delivery, and sensing systems housed in the GI tract.
... We reviewed the literature for other studies of preferred beverage temperature [16][17][18]23,[31][32][33][34][35][36][37][38][39][40] (Table 4), and found that the mean preferred tea temperature in our study was 1.5°C higher than any other studied population. It should be noted that the various studies presented in Table 4 use various methodologies to assess temperature and this limits the ability to compare them, and numerous studies concerning beverage temperature do not report descriptive statistics for temperature. ...
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Background Esophageal squamous cell carcinoma (ESCC) is common in certain areas worldwide. One area, western Kenya, has a high risk of ESCC, including many young cases (<30 years old), but has limited prior study of potential risk factors. Thermal injury from hot food and beverages and exposure to polycyclic aromatic hydrocarbons (PAHs) have been proposed as important risk factors for ESCC in other settings. The beverage of choice in western Kenya is milky tea (chai). Methods Healthy individuals >18 years of age who were accompanying relatives to an endoscopy unit were recruited to participate. The preferred initial temperature of chai consumption in these adults was measured by questionnaire and digital thermometer. Comparisons of these results were assessed by kappa statistics. Concentrations of 26 selected PAHs were determined by gas chromatography/mass spectrometry in samples of 11 brands of commercial tea leaves commonly consumed in Kenya. Results Kappa values demonstrated moderate agreement between questionnaire responses and measured temperatures. The mean preferred chai temperatures were 72.1 °C overall, 72.6 °C in men (n = 78), and 70.2 °C in women (n = 22; p < 0.05). Chai temperature did not significantly differ by age or ethnic group. The PAH levels in the commercial Kenyan tea leaves were uniformly low (total PAH < 300 ng/g of leaves). Conclusions Study participants drink chai at higher temperatures than previously reported in other high-risk ESCC regions. Chai is not, however, a source of significant PAH exposure. Very hot chai consumption should be further evaluated as a risk factor for ESCC in Kenya with the proposed questionnaire.
... » 114. Jahrgang | Juli 2018 | DLR Trotz der aktuellen Medienpräsenz gibt es bislang nur wenige Studien darüber, wie heiß Heißgetränke in der Regel verzehrt werden [7][8][9][10]. Erst im letzten Jahr wurde im Raum Süddeutschland eine maßgebliche Studie durchgeführt, bei der die Ausgabetemperaturen von Kaffee verschiedener Maschinentypen ermittelt und bewertet wurden. ...
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The International Agency for Research on Cancer (IARC) evaluates "very hot" (> 65 °;C) beverages as "probably carcinogenic". This leads to the question how cooling of coffee is influenced by material properties and filling capacity of different mugs and to-go-cups. How long does it take to cool down coffee to less than 65 °C? With three temperature sensors inside the cup, the cooling time of 88 °C hot water to below 65 °C is measured. Hot water has similar cooling behavior as coffee. Between two to five measurements are conducted per cup for both 237 mL and 355 mL filling volume. The cooling process slows down for larger filling volume. The average cooling time to less than 65 °C is between 20 to 24 min in disposable cups. In contrast, cooling time is between 29 to 40 min in reusable cups. Cooling time for hot coffee is largely dependent on material properties and filling capacity. Coffee cools down most quickly in ceramic cups, whereas it takes the longest time in airproof thick-walled reusable cups of stainless steel. © 2018 Wissenschaftliche Verlagsgesellschaft mbH. All rights reserved.
... According to Borchgrevink, Susskind, and Tarras (1999), the ideal serving temperature for hot brewed coffee was found to be 68 to 79°C (154 to 174°F). However, other studies have suggested a recommended serving temperature according to consumer's preference to be around 50-60°C (Brown & Diller 2007;Lee & O'Mahony 2002;Pipatsattayanuwong, Lee, Lau, & O'Mahony 2001). Those differences suggest variation when it comes to serving temperatures of coffee. ...
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The sensory properties of coffee are impacted by various factors such as coffee origin, degree of roasting and methods of consumption. This study analyzed impact of consumption temperature on 36 flavor attributes of hot brewed coffee by descriptive sensory analysis. Different coffee samples (2 Arabica, 1 Robusta, and 1 Blended Arabica and Robusta) were consumed at 50 °C, 60 °C and 70 °C. Data were assessed using an Analysis of Variance, mixed effect model with least square means and significance level of α = 0.05. Results showed significant interactions of consumption temperature and coffee samples for attributes such as coffee identity, fidelity, and blendedness. The consumption temperature played a major impact on perceived flavor attributes of coffee and influenced Arabica, Blended and Robusta coffee differently. Coffee identity and fidelity significantly increased with an increase in all temperatures, but most attributes showed significantly higher intensity only for samples consumed at 70 °C regardless of insignificant differences at 60 °C and 50 °C.
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Temperature is an important characteristic of food and drink. In addition to food-intrinsic temperature (i.e. serving temperature), consumers often experience food-extrinsic temperature (e.g. physical warmth). Emerging research on cross-modal correspondence has revealed that people reliably associate temperature with other sensory features. Building on the literature on cross-modal correspondence and sensation transference theory, the present study aimed to reveal mental representations of temperature–taste correspondence and cross-modal mental representations influencing corresponding sensory/hedonic perceptions of beverages, with a focus on manipulating food-extrinsic warmth. To reveal mental representations of temperature–taste correspondence, Experiment 1 investigated whether temperature words (warm, cool) are associated with sensory/hedonic attributes (e.g. sweet, sour, salty, bitter). The results of Experiment 1 demonstrated that warm (vs. cool) was matched more with saltiness, tastiness, healthfulness, and preference (intention to buy), whereas cool (vs. warm) was matched more with sourness and freshness. Experiment 2 assessed whether cross-modal mental representations influence corresponding sensory/hedonic perceptions of beverages. The participants wore hot and cold pads and rated sensory/hedonic attributes of Japanese tea (Experiment 2a) or black coffee (Experiment 2b) before and after tasting it. The results of Experiment 2a demonstrated that physical warmth (vs. coldness) increased healthfulness and the intention to buy Japanese tea. The results of Experiment 2b did not reveal any effects of physical warmth on sensory/hedonic ratings. These findings provide evidence of taste–temperature correspondence and provide preliminary support for the influence of food-extrinsic warmth on taste attributes related to positivity.
Hot beverages are served ubiquitously in the food‐service industry as well as at residences and other venues. Coffee and tea beverages, in particular, are brewed at temperatures that are sufficiently high to cause immediate and serious risk for scald injuries. On the other hand, numerous research studies have been performed to identify the preferred consumption temperatures for hot beverages. The outcome of these mutually reinforcing studies is that the preferred drinking temperatures are significantly below the often‐encountered brewing temperatures (∼200 °F). Consequently, there is great need to distinguish brewing temperatures from serving temperatures. Serving consumers beverages at very high temperatures is not only unnecessary (from a preference standpoint) but also unsafe. An appropriate range for service temperatures is (130 to 160 °F). Often times, hot beverages are served at temperatures near their brewing temperature; far hotter than preferred by consumers. This practice creates unnecessary risk to the consumer. A more rationale recommended range of service temperatures is 130 to 160 °F. This recommendation balances a range of consumer preferences and safety.
An infant sustained second- and third-degree scald burns of the oropharynx from drinking formula heated in a microwave oven. The circumstances leading to the scald injuries were recreated. Factors contributing to the injury included the volume of formula, the initial temperature of the formula, and the temperature gradient between the liquid core and the bottle surface after microwave heating. These studies indicate that infant formula should be warmed only with extreme care in microwave ovens and should be tested for suitability of temperature prior to feeding.
High-energy light from an argon laser was applied to human oral mucosa in order to investigate regional pain sensitivity. Significant regional differences in sensory and pain thresholds were observed between the test sites on the hard and soft palatal mucosa, the buccal mucosa, the tongue, the lower lip, and the skin on the hand. Pain thresholds were lowest on the tip of the tongue and highest on the hard palate. Sensory and pain thresholds were influenced by different stimulus parameters: pulse duration and laser beam diameter. Blackening of the mucosa in regions with high optical reflectance, such as the hard palate, increased light absorption and, hence, reduced both thresholds significantly. Reflectance spectrophotometric measurements indicated that the hard palatal mucosa reflected argon laser light about 1.5 times more than the tip of the tongue. The different threshold values could, in part, be ascribed to different reflectance and absorption properties of the mucosal areas but also indicated substantial regional variation in pain sensitivity of the human oral mucosa. Measurement of laser thresholds is an appropriate and standardized method for investigating sensory differences in human oral mucosa and may be used to study various pain conditions e.g., burning mouth syndrome.
ABSTRACTR-index measures were obtained from judges who ranked black coffees for preferred drinking temperature. Preferred temperatures were above thermal pain and thermal damage thresholds. The least preferred temperature was below the oral thermal pain threshold. Similar results were obtained with a ranking for temperatures that judges felt were most likely to be served in a coffee shop. Observations of customers in coffee shops indicated that they began sipping coffee at similar high temperatures.
The hospitality and food science literatures specify brewing and holding temperatures for hot beverages such as coffee, while the medical literature states that those very beverage temperatures will cause scalds and harm. These two specifications are at odds with one another, and recommend different approaches to serving and handling hot beverages. Considering the disparate standards it is interesting to note that no one has reported asking consumers of hot beverages at which temperature they prefer to consume their hot beverages. This pilot study is a first step in determining the consumer preferred hot beverage temperature. The research intent is to see if a temperature, or temperature range, can be established at which consumers drink a hot beverage, in this case coffee. The research is particularly relevant given recent litigation relative to spills and burns at foodservice operations, and subsequent changes in holding temperatures at some quick service restaurant chains. The findings suggest that the standard brewing and holding temperatures are too high for consumption, while the temperature identified as the medical literature threshold for burns is too low for consumption. ©
Aproblem central to sensory difference testing is response bias. There are two experimental strategies for dealing with this problem. The first is to use forced choice procedures, like the common duo-trio or triangle tests, while the second is to use signal detection measures like d′, P(A) and the R-index. These strategies are explained and discussed. The relationship between the R-index and the other signal detection measures is explained. The relationship between R-index values obtained by rating and ranking is explored, as are the alternative computations of the R-index by ranking: Rjb and Rmat.
Two experiments demonstrate that the sensitivity to heat pain varies significantly within the oral-facial region. Although the chin, the vermilion border of the lip, and the tonguetip are about equally sensitive, the mucosal lip and the dorsum of the tongue produce thresholds approximately 1.5°C higher. The spatial heterogeneity of heat-pain thresholds is discussed in relation both to local variations in perceived warmth in the same areas and to the neural and physical variables that might underlie them.
Two young children who sustained thermal injuries to the epiglottis (or "thermal epiglottitis") after swallowing hot beverages are reported. Findings, clinically and radiologically, in both children were similar to acute infectious epiglottitis. Children with these injuries are at risk for significant upper airway obstruction which may progress for several hours. Children in whom thermal epiglottitis is suspected should be approached with the same caution and preparedness for emergency airway management and pediatric intensive care afforded those with acute infectious epiglottitis.