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1.
When identical milk samples are presented, only 30% of participants respond with a “no preference” rating. Stability of the “no preference” rating was studied under a variety of conditions, having consumer panelists rate both identical and different pairs of milk samples with varying fat content. The proportion of participants choosing the “no preference” option, when the samples in the pair were identical, was largely consistent despite manipulation of pretest conditions and changes in test questions and answer formats. However, when the milk preference test was preceded by a same/different test, and those responding “same” were assumed to have no preference, the percent of “no preference” was two to three times larger for identical test samples (60–69%). Thus by branching the question, the “false preference” choice for identical milks was lowered. Among those responding “different” to identical milks, the false‐alarm rate increased to 91%, suggesting that perception of (spurious or momentary) differences is driving at least part of the preference choice.  相似文献   

2.
The present study considers the influence of reducing the fat content of ovine milk on the sensory and instrumental texture characteristics of the resulting cheeses. Three manufacturing runs were performed. In each run three cheese batches were manufactured using milks with differing percentage fat contents (8%, 4%, and 2% fat). Analysis of cheese samples was performed at 60, 90, and 120 days of ripening.
The instrumental method used to evaluate cheese texture was uniaxial compression at constant speed, taking readings of stress, strain, and modulus of elasticity (E). Statisticalanalysis revealed differences forboth the differentfat contents and the ripening times considered. Instrumental parameter values increased with lower cheese fat contents; with a 20% reduction in the fat to dry matter content from full-fat to reduced-fat cheeses, resulting in a 35% increase in maximum stress and in the slope of the stress-strain curve at the end of ripening. The greatest sensory differences between samples were recorded for firmness.  相似文献   

3.
4.
Selenium content of 1028 milk and milk products of Turkey are presented in this study. The selenium content of human milk (colostrum, transitional, and mature milk), various kinds of milk [cow, sheep, goat, buffalo, paper boxes (3%, 1.5%, 0.012% fat), bottled milk, condensed milk (10% fat), mineral added milk (1.6%), and banana, strawberry, and chocolate milk] and milk products (kefir, yogurt, Ayran, various cheese, coffee cream, ice cream, butter, margarine, milk powder, and fruit yogurt) in Turkey were determined by a spectrofluorometric method. The selenium levels of cow milks collected from 57 cities in Turkey were also determined. Selenium levels in cow milk varied with geographical location in Turkey and were found to be lowest for Van and highest for Aksaray. The results [milk (cow, sheep, goat, buffalo and human) and milks products] were compared with literature data from different countries.  相似文献   

5.
Focusing primarily, but not exclusively, on urban and periurban Papua New Guinea (PNG), we discuss the significance of instant ramen noodles to those now known as the “bottom of the pyramid” (BOP). Although instant noodles are remarkable in that they are eaten by virtually everyone in the world, albeit in different amounts and for different reasons, they are marketed in PNG specifically as a “popularly positioned product” (PPP) for the BOP. Cheap, convenient, tasty, filling, and shelf stable, they are a modern addition to Sidney Mintz's classic “proletarian hunger killers” of sugar, tea, and coffee. But, we argue, instant noodles have a distinctive contemporary role: they do more than sustain the poor; they transform them into the aspiring consumers of the BOP. As such, instant noodles can be viewed as an antifriction device, greasing the skids of capitalism as it extends its reach.  相似文献   

6.
Assessed under low-intensity red illumination, homogenized and thickened higher fat milk samples evoked higher sensory ratings of creaminess than did the unhomogenized or lower-fat milks that had not been thickened to the viscosity of double cream. Furthermore, perceptual ratings of fat content showed the same dependency on homogenization, higher fat and thickness and were entirely accounted for by the creaminess ratings. This indicates that assessors recognize the type of milk or cream most similar to a rated standard and infer its fat content on the basis of tactile patterns produced in the mouth by forces at the surface of small and even-sized dairy fat globules when bulk forces are produced by sufficient viscosity.  相似文献   

7.
SUMMARY: The bacterial colony count of raw milk and of milk powder using milk agar prepared from a proprietary brand of the dehydrated medium has been compared with that obtained using the fresh medium prepared in the laboratory.
No significant difference was found in 17 milks which were examined using the roll-tube technique and 8 replicates/medium but in a second series of 32 milks the plate count (3 replicates/medium) was significantly lower on the reconstituted than on the fresh medium.
Some milk powders gave a much lower plate count on the reconstituted medium, due to the inability of the latter to support adequate growth of Streptococcus thermophilus.  相似文献   

8.
Hypothesized relationships between milk composition and life history traits were examined by analyzing mid-lactation milks of seven lemurs (Eulemur fulvus, E. macaco, E. rubriventer, E. mongoz, Varecia variegata, Hapalemur griseus, Lemur catta), three bushbabies (Otolemur crassicaudatus, O. garnettii, Galago moholi), and two lorises (Nycticebus coucang, Loris tardigradus); partial data were also obtained for the lemuroid Cheirogaleus medius. There were significant differences in milk composition among species within either Eulemur or Otolemur, but the four genera for which multiple samples were available (Eulemur, Varecia, Otolemur, and Nycticebus) exhibited large composition differences. Eulemur milk was, on average, very dilute (9.9% dry matter) and low in energy (0.49 kcal/g). These milks contained 0.9% fat, 1.2% protein, and 8.4% carbohydrate on a fresh weight basis. Protein energy comprised only about 15% of total milk energy. Varecia had significantly higher dry matter (13.5%), fat (3.2%), protein (4.2%), gross energy (0.80 kcal/g), and protein energy: total energy ratio (28%) than Eulemur. Milks of the lorisoid genera Otolemur and Nycticebus were very similar, and both had significantly higher dry matter (18.3, 16.3%), fat (7.6, 7.0%), and gross energy concentration (1.27, 1.13 kcal/g) than either lemuroid genus. Otolemur milk was higher in protein than Nycticebus milk. We conclude that lorises, bushbabies, and perhaps cheirogaleids produce relatively rich, energy-dense milks in comparison with anthropoid primates. However, dilute milks appear to be uniformly found among species of Eulemur and perhaps in Lemur catta. The milk of Varecia (and perhaps Hapalemur) is intermediate in composition. Differences in milk composition among prosimians may be related to differences in maternal care: prosimians that carry their young during lactation produce more dilute milks than do species which leave their young unattended for prolonged periods. When looking at primates as a whole, however, the picture is somewhat less clear, since the milks of some “parkers” like Varecia do closely resemble those of large anthropoid primates who carry their young. Am. J. Primatol. 41:195–211, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

9.
Shelf-stable milk, also known as ultra-high-temperature (UHT) milk is the most common form of milk in many parts of the world. This study compared the differences in flavor and texture of 37 commercially available UHT and sterilized milk samples including whole, 2% reduced-fat and low-fat milk obtained from markets in seven countries: France ( n =  2), Italy ( n =  11), Japan ( n =  1), Korea ( n =  2), Peru ( n =  3), Thailand ( n =  13) and the U.S.A. ( n =  5). Five highly trained panelists used flavor and texture profiling to describe the sensory properties of each milk sample. Data were analyzed by principal component analysis and hierarchical cluster analysis. Higher levels of processed, chalky, brown and cooked flavor notes generally corresponded to lower levels of fresh dairy flavor characteristics. In general, samples did not vary consistently within a country. Fat content did not correlate with dairy fat flavor or with viscosity. This research suggests that companies' manufacturing processes for UHT milk may have more impact than country or fat content in determining sensory properties of UHT milk.

PRACTICAL APPLICATIONS


Sensory properties of UHT milk from different countries developed in this study could be used by the dairy industry to understand the similarities and differences of UHT milk characteristics from different regions and to modify UHT milk characteristics to meet consumers' criteria or expectation. The study suggests that manufacturers who want to improve quality of UHT milk by modify flavor and texture properties should focus on improvements to the manufacturing processes.  相似文献   

10.
“Solid-substrate” fermentation developed in the Orient is a very useful fermentation method. It is presently used to produce a variety of foods, beverages and related products. Solid-substrate fermentation products utilizing fungi including soy sauce, miso and tempe, ontjom, sake, and bread have been produced for centuries at the home and village level. They are examples of economical methods of preserving and improving the flavor, texture and nutritive values of cereal/legume substrates. “Solid-substrate” fermentation is also applied to animal products such as milk to produce Roquefort and Camembert cheeses which diversify the food flavors available to man “Solid-substrate”fermentation has certain advantages. The substrate is concentrated; the product can be extracted with relatively small quantities of solvent; the product can be easily dehydrated; moisture level can be controlled favoring the desired organisms; enzyme concentration is generally higher than is submerged fermentation; product concentration is generally higher than in submerged cultures; it is the only technique that yields true mushroom fruiting bodies and it can be used not only for production of crude enzyme concentrates (koji) but also for raising the protein content of high starch substrates. It also can be used to increase the content of vitamins at low cost. Disadvantages of “solid-substrates”from the modern industrial processing view point are the greater difficulty of handling solid substrate and the greater difficulty of controlling the fermentation parameters, temperature, pH and oxygen, and rate of microbial growth compared with liquid submerged fermentations.  相似文献   

11.
One objective of this study was to compare taste test ratings with amounts consumed and postconsumption ratings made as iced teas of different strengths were repeatedly consumed. The second objective was to determine whether sensory specific satiety could be used as a rapid indicator of long term acceptability of the teas. Subjects first rated their liking of and the flavor intensity of several samples of lemon flavored iced tea. Two tea concentrations were selected from this test to represent distinctly different flavor intensities. Taste test liking ratings of the strong concentration were higher than those of the weak concentration. Subjects consumed either the strong or the weak iced tea ad lib on 20 different afternoons over a 2-month period and rated their liking of the tea after each session. We measured the amount of tea consumed each time. On repeated consumption the subjects liked the weaker tea better than the stronger tea. Subjects consumed about the same amount of each tea. A different group of 15 subjects participated in a sensory specific satiety study of the same two teas. Those subjects drank more of the weak tea than the strong tea.  相似文献   

12.
Sheep milk, compared with cow and goat milk, had a protective effect on Gram-negative bacteria and Listeria spp. heated at 65°C in a test-tube method. This effect was not solely due to fat content as cow milk artificially reconstituted to 10% homologous fat was not as protective. Listeria monocytogenes in whole sheep, cow and goat milks at an inoculum level of 1 times 106 cfu ml-1 was heated at 68°C for 15 s in the plate pasteurizer and survival was only detected in whole sheep milk after heating. Whole sheep, cow and goat milks containing high levels of L. monocytogenes (1 times 106 cfu ml-1) could not survive the current HTST plate pasteurization protocol.  相似文献   

13.
Common marmosets, one of the smallest anthropoid primates, have a relatively high reproductive rate, capable of producing twins or triplets twice per year. Growth and development of infants is relatively rapid, and lactation is relatively short at less than 3 months. Although mean values for the proximate composition (dry matter, protein, fat and sugar) of captive common marmoset milks fall within anthropoid norms, composition is highly variable among individual samples, with concentrations of milk fat ranging from below 1 to over 10%. To examine the extent to which this variation might be a consequence of captive conditions, we collected milk samples from wild common marmosets freely living on a farm in the state of Rio de Janeiro, Brazil. The proximate composition of the milk samples was assayed using identical techniques as used for the captive marmoset milks. The composition of the milk of wild common marmosets was also variable, but tended to be lower in dry matter, fat, protein and gross energy, and higher in sugar than milks from captive animals. Interestingly, the percentage of estimated gross energy from the protein fraction of the milks was relatively constant in both wild and captive marmosets and did not differ between wild and captive animals: 1 kcal of common marmoset milk contains on average (+/-SEM) 0.035+/-.001 g of protein regardless of the gross energy content of the milk or whether the milk was from a wild or captive animal. In contrast, in 1 kcal of low-energy milks, the amount of sugar was significantly higher and the amount of fat significantly lower than in 1 kcal of high-energy milks. Thus, common marmoset milk exhibits axes of variability (especially fat concentration) as well as a significant stability in the relative amount of protein.  相似文献   

14.
A consumer panel comprising 60 females evaluated three coffee whiteners and fresh milk for a number of sensory attributes including liking of flavor and appearance, overall liking, natural flavor and odor, creaminess and watery flavor. Fourier analysis was used to produce a plot which readily identified the whiteners with sensory profiles most similar to fresh milk. More importantly, the whitener whose sensory profile was significantly different from that of fresh milk was identified from the Fourier plot, something which could not be done by traditional univariate methods or even by an overall discriminant analysis.  相似文献   

15.
Coffee powders available commercially are of different qualities. The quality variations may be due to inherent quality of coffee beans, storage time and packaging materials used. Sensory profiles of brewed and soluble coffees were studied through profiling. Canonical discriminant analysis (CDA) used for positioning the different coffee samples showed that freshly made coffee from plantation arabica (PA), Pea berry (PB), PA with chicory (PAC), PB with chicory (PBC) and their blends viz. PA + PB and PAC + PBC occupied the quadrant where coffee aroma and overall quality rated higher. Other roasted & ground (R&G) coffee (market) samples were positioned where oily, fermented, musty, stale and caramelized notes dominated. In case of soluble coffee, the flavored coffee procured from the western market (S3, S6, S9 and S8) dominated the quadrant where other added flavor and oily notes dominated. The typical soluble (instant) coffee without any added flavor S10, S12 and S13 occupied another quadrant. The soluble coffee powder with spice incorporation took a separate quadrant where other added flavor and bitter taste dominated. The dominant quality attributes for the groups are different and are discussed in relation to the directional vectors.  相似文献   

16.
Lactating mice were fed either a low fat or a high fat diet. Milk samples were collected and the composition was examined. Triglyceride and free fatty acid contents were greatly reduced in the milks of high fat diet group, while protein and lactose contents were almost the same between both diet groups. Although the energy content of each component was also lower in milk of high fat diet group, there was apparently no significant difference in the growth of the pups raised by either diet group. This discrepancy might be in part explained by a hypothesis that the pups might monitor calorie content in milk and keep suckling until the energy intake reaches their satisfaction. Moreover, nearly the same amounts of major milk fat globule membrane proteins MFG-E8 and butyrophilin were shown to be present in the milks from both diet groups and gene expression of both proteins in the mammary glands were also indistinguishable, suggesting that production of major MFGM components is not simply related to fat production and secretion.  相似文献   

17.
Lactating mice were fed either a low fat or a high fat diet. Milk samples were collected and the composition was examined. Triglyceride and free fatty acid contents were greatly reduced in the milks of high fat diet group, while protein and lactose contents were almost the same between both diet groups. Although the energy content of each component was also lower in milk of high fat diet group, there was apparently no significant difference in the growth of the pups raised by either diet group. This discrepancy might be in part explained by a hypothesis that the pups might monitor calorie content in milk and keep suckling until the energy intake reaches their satisfaction. Moreover, nearly the same amounts of major milk fat globule membrane proteins MFG-E8 and butyrophilin were shown to be present in the milks from both diet groups and gene expression of both proteins in the mammary glands were also indistinguishable, suggesting that production of major MFGM components is not simply related to fat production and secretion.  相似文献   

18.
Coffee prepared in the usual way for drinking contains a substance(s) that is mutagenic to Salmonella typhimurium TA100 without mammalian microsomal enzymes. One cup of coffee (200 ml) contains mutagen(s) inducing 1.4-4.6 X 10(5) revertants under standard conditions. Instant coffee too is mutagenic to TA100 and one cup of instant coffee prepared from 1 g of coffee powder and 200 ml of water induced 5.6-5.8 X 10(4) revertants of TA100. Caffeine-free instant coffee also has similar mutagenicity. Addition of microsomal enzymes abolished the mutagenicity. Black tea, green tea and Japanese roasted tea were also mutagenic to TA100 without S9 mix and one cup of these teas prepared in the ordinary way produced 1.7-3.8 X 10(4) revertants of TA100. Black tea and green tea were also mutagenic to TA98 in the presence of S9 mix after treatment with a glycosidase from Aspergillus niger, hesperidinase. This type of mutagen in one cup of black tea induced 2.4 X 10(5) revertants of TA98.  相似文献   

19.
20.
The objective of this study was to demonstrate that the dimensions of a sensory booth modified to comply with the Americans with Disabilities Act of 1990 (ADA) guidelines have no impact on consumer evaluations of chocolate pudding. One set of booths each were constructed per ASTM and ADA guidelines. Control pudding was prepared according to package directions with 2% fat milk; other treatments were modified with red food coloring, sugar or nonfat milk. Twenty-four panelists evaluated instant chocolate puddings in directional difference and hedonic tests in each type of booth. Booth type and test date had no effect on judgments.  相似文献   

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