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Sensory evaluation of isolated natural capsaicinoids showed that there was a significant linear relationship between pungency and concentration. Detection thresholds were evaluated using an ASTM method. Pungency thresholds were calculated using the established relationships between pungency and concentration of individual compounds. Total pungency of a mixture of capsaicinoids was highly correlated with the sum of pungencies of individual capsaicinoids. Determination of the total pungency of Capsicum extracts can be accomplished by adding the pungencies of individual capsaicinoids upon multiplication of their pungency threshold values by their respective concentrations.

Two different panels were trained to evaluate the character of four aromatic and two nonaromatic rices. The judges used terms with which they were familiar to describe the odor of aromatic rice: pandan for the orientals and popcorn for the nonorientals. The rice volatiles were separated by a gas chromatograph equipped with a packed column and a sniffing port. The peaks possessing the aromatic principle were identified by GC-MS and correlated with the desirable aroma terms. 2-Acetyl-l-pyrroline showed highly significant positive correlations with the descriptive terms; hexanol showed negative correlations.

Seven apple varieties and Russet Burbank potatoes were peeled by caustics to save labor and reduce peeling losses. The procedures included the use of an automated peeling line employing warm caustics followed by pressurized steam, and a reel-washer. For apples peeled at 150°F and with added wax-penetrant the peeling losses ranged from 3–8%. The replacement of NaOH by KOH gave reductions in peeling losses of up to 25%. For potatoes dipped in caustics at 170°F the peeling losses ran from 8–17%, depending mainly upon prior storage times. The possibility of peeling potatoes in very hot (280°F) concentrated (50%) KOH was tried and gave excellent results, with no heat-ring, and a KOH loss of only 0.56%.

Nine experimental lots of grape jelly were made with different amounts of pectin and dextrose or invert syrup replacements for sucrose. A commercial grape jelly was used as a reference. The jellies were evaluated for acceptability, appearance (color and sheen), flavor and texture (spreadability and mouth feel). The pH, percent soluble solids, percent sag, shear force required to puncture the gel, percent dextrose and gas-liquid chromatographic (GLC) profiles of an extract-concentrate of the jellies were also determined. A computer program which calculates a contingency table for products and score levels was applied to the data to determine the intervals between scores and to feed back the data on a random basis to determine whether the panelists were showing true preference or their choices were approaching randomness. One can thus compare the evidence on experimental and simulated data and decide for himself whether he agrees with any chosen level of significance. Flavor and texture were almost equally correlated with acceptability. Although appearance was less well correlated, this was not because it was unimportant but because the range was less. The various multiple correlation coefficients were calculated. Greater differentiation between products was attained by using the percent sag and shear force measurements in combination with GLC peaks than by using GLC peaks alone. The products tested fell into three categories: the commercial product received the highest preference rating followed by the experimental products containing from 5–7g of pectin; the high pectin (8g) received the lowest preference rating.

Eighty-six descriptors commonly used to characterize wines were evaluated by 86 respondents. The list was reduced to 33 descriptors which had the greatest meaning. Panels of 33 and 18 judges, respectively, evaluated 14 red and 12 white table wines for acceptability. For each descriptor, each wine was compared against a red or white reference wine. The tines had originally been purchased based on price and general repute as to quality. The panels did not rank the most expensive wines as the most acceptable. For the red wines, 27 descriptors were used for factor analysis. Eight factors were extracted and 14 well defined, oblique simple-structure planes were identified. For the white wines, six factors were extracted and 11 planes identified.

SUMMARY— The flavor threshold concentrations were determined for 23 compounds composing an artificial peach beverage base. The threshold levels ranged from 52 ppm to 0.4 ppb. The threshold values were used in sub-threshold, additive sub-threshold, and concentration trials. Sub-threshold and additive sub-threshold effects resulted from only a few of the flavor combinations tried. Change in concentration of one compound in a mixture of six compounds was not readily detectable organoleptically. The difference in concentration could be detected gas chromatographically, but only if the mixtures were extracted with pentane and concentrated. By dividing the respective threshold values into the amount of each compound present in the beverage, a factor was calculated, called the “unit flavor base,” which indicated the relative importance of each compound as a flavor substance in the peach beverage. By dividing the gas chromatographic peak heights by the respective threshold values, gas chromatographic response was weighted for flavor importance. When the unit flavor base and weighted gas chromatographic response were converted into logarithms, the relation between the values was nearly linear. The correlation coefficient was 0.8691 (significant @ 0.01).

SUMMARY The influence of 11 anthocyanin pigments on glucose oxidation by resting cells of Escherichia coli K-12, Staphylococcus aureus, Lactobacillus casei 7469, Salmonella enteritidis, S. typhosa, Proteus vulgaris, and Aerobacter aerogenes was determined with a manometric technique. Malvidin, delphinidin, and the monoglucosides of malvidin, pelargonidin, petunidin, and delphinidin generally inhibited glucose oxidation by the test organisms, but in the absence of glucose the organisms oxidized the pigments. The action of the anthocyanins on respiration varied with PH. Apigeninidin chloride, 5.desoxy-apigeninidinchloride- 4′-methyl-ether, and 5-desoxy-3′-methoxy-apigeninidin-chloride-4′-methyl-ether inhibited glucose oxidation by S. aureus. The latter two compounds and 3′-methoxy-apigeninidin-chloride-4′-methyl-ether had a similar effect on E. coli. The depressing effect of glycosidic anthocyanins on the respiration of S. aureus was reversed by the addition of MgCl2.

SUMMARY Temperature amplitudes to 160° and Q10 values from 1 to 30 were integrated to derive coefficients of fluctuation. Multiplication of the coefficient by the reaction rate at the mean temperature permits ready calculation of the average reaction rate when temperature fluctuations assume either a square-wave or sinusoidal form of cycling. The method is applicable to any temperature scale. Ascorbic acid solutions were less stable when the temperature was cycled from −6 to 30°F than when held steady at 12°F. Aerobacter aerogenes and Staphylococcus aureus cultures incubated under cyclic conditions from 40 to 80°F usually grew quicker than cultures incubated at a constant temperature of 60°F.

SUMMARY Two methods of discriminant analysis, Chi-square tests, “t” tests and analysis of variance were applied to gas-liquid chromatographic (GLC) data to compare GLC measurements of food volatiles with organoleptic evaluation of flavor. Model systems composed of ethyl butyrate, ethyl heptylate and benzaldehyde were used for one set of trials. A second system consisted of blends of Pepsi-Cola® and Coca-Cola®. The stepwise discriminant analysis (SDA) procedure described by Powers et al. (1968) was only moderately successful in classifying the mixtures when applied to the GLC data for the model systems, but the cola blends could be classified readily. From GLC data, cola blends differing from each other by only 7–10% could be distinguished. A new discriminant analysis program, designated MUDAID by its originator (Bargmann, 1967), is more useful for predictive purposes. The analysis yields the correlation coefficients for each peak area with sample differences and the weighting factors. Discriminant equations can thus be written. By substitution of measurement values for unknowns, their identity may be predicted. Organoleptic subthreshold additive effects could not be demonstrated with binary mixtures of flavor substances, but judge-compound interaction effects were observed.

SUMMARY Solutions of glycine, glutamic acid, lysine, methionine, and phenylalanine adjusted to pH 6.5 were reacted separately with glucose, fructose, maltose, and sucrose at 100 and 180°C. Some of the aromas generated were reminiscent of foods, whereas others were distinctly unpleasant. Ethanal, propanal, acetone, isobutanal, aerolein, butanal, 2-butanone, 2,3-butane-dione, erotanal, 2-pentanone, and heptanal were identified as end products in one or more of the 20 mixtures. The glutamic acid-glucose mixture was also heated at 100 and 180°C after being adjusted to pH 5.0 and 8.0. Of the compounds above, isobutanal and heptanal were not formed. Pentaual was formed at 100° but not at 180°C. A synthetic potato medium containing glucose and glutamic acid heated at 100°C yielded ethanal, propanal, acetone, butanal, 2-butanone, 2,3-butanedione, and crotonal. A potato extract heated at 180° differed from the synthetic potato medium heated at 100° in the products formed. Not formed were 2-butanone and 2,3-butauedione; pentanal, heptanal and hexen-l-al were formed. In all, 85 carbonyls were detected in the various mixtures or substrates.

SUMMARY Gas chromatographic methods were developed for the separation of apigeninidin compounds, pelargonidin, cyanidin, delphinidin, petunidin, and malvidin. Protocatechuie, p-hydroxybenzoic, gallie, vanillie, and syringic acids–which are useful for the identification of particular anthocyanidins–were also amena-able to gas chromatographic analysis. Phlorglucinol could likewise he measured. Separation of rhamnose, ribose, xylose, fructose, ga-lactose, and glucose was good. Except for fructose, the others are common glycosidie sugars and aid in differentiating anthocyanins. Retention times were determined for the monogluco-sides of delphinidin, petunidin, pelargonidin, and malvidin; for a delphinidin glycoside extracted from wild grape hyacinths; and for arhutin, hesperidin, rutin, and quercitrin. Betanin likewise was volatile as the silyl ether. Rhamnetin, catechin, and quercetin yielded good gas chromatographic waves. Phenolphthalein and naphthorescoreinol were sometimes used as internal standards. The silyl ethers or esters above were prepared in pyridine or dimethyl sulfoxide. The data suggest that gas chromatography might he used for preparative as well as for identification purposes.

SUMMARY— Stepwise discriminant analysis for classifying food samples (known independently to differ in flavor) is illustrated by computer analysis of gas chromatograms from roasted coffee and potato chips. Four lots of coffee prepared so as to differ in flavor were scored organoleptically, steam distilled, and the distillate examined gas chromatographically. By calculating all possible ratios among peak heights and subjecting these ratios to discriminant analysis, the coffee could be classified into the four flavor categories from the gas chromatographic data. The discriminant analysis procedure was set to select the ratio most critical in differentiating among the chromatograms, then move on to the next most efficient ratio until the samples were classified. The same thing was done for potato chips except headspace volatiles were used for the gas chromatographic analysis. Not only does the procedure described enable flavor to be correlated with gas chromatographic data, but the efficiency values for each ratio are useful. A compound devoid of flavor can conceivably be highly correlated with flavor; however, there is a good chance that a compound highly correlated with flavor is a flavor substance itself.

SUMMARY Pelargonidin 3-monoglucoside was isolated from frozen strawberries and subjected to heat degradation in IN HCl. The six fractions isolated were characterized chemically and physically. The unheated and heated pigment inhibited the growth of Escherichia coli and Staphylococcus aureus, and exerted both a stimulatory and inhibitory effect on Lactobacillus casei culture. The stimulation may be due to a decrease in the oxidation-reduction potential of the media affected by the pigment, and/or the ability of the organism to split the β-glyeosyl bond and use the glucose moiety. The influence on growth of the test organisms of the various fractions resulting from heating the pigment was reported.

SUMMARY Six anthocyanins were isolated from Cabernet Sauvignon grapes. Four major and one minor pigment were identified by paper chromatography, color reactions, and spectroscopy. The four major anthocyanins were identified as delphinidin-3-monoglucoside, petunidin-3-monoglucoside, malvidin-3-monoglncoside, and malvidin-3-monoglueoside acetylated with chlorogenic acid. Malvidin-3-monoglucoside was the most abundant pigment of the grapes. One of the minor pigments was identified as petunidin.

SUMMARY The volatiles of canned tomatoes acidified with citric and with malic acid differed significantly from those of control, nonacidified tomatoes and from each other. Tomatoes treated with sugar and acid also differed significantly in volatiles. Blends of tomato juice prepared from various proportions of canned juice and juice reconstituted from tomato powder differed significantly in flavor. Through the application of discriminant analysis (DA) to gas-liquid chromatographic (GLC) data, blends could usually be predicted correctly from the discriminant equations. Peanuts roasted for 12, 16, 20 and 24 min were similarly evaluated organoleptically and gas chromatographically. For the 3 products above, one or a few peaks were generally not sufficient to characterize the sample. When 10–15 peak areas were used to make the discrimination, each of the 3 products could be catagorized readily according to treatment.

SUMMARY The metal-complexing properties of malvidin-3-monoglucoside, petunidin-3-monoglucoside, and 3′-methoxy-apigeninidin-chloride-4′-methyl-ether were studied polarographically and spectrophotometrically to complement bacteriological findings previously made. The molar ratios at which malvidin-3- monoglucoside combined with cupric ions depended on the pH of the supporting electrolyte solutions. The molar ratio of cupric ion to malvidin-3-monoglucoside was 2:1 at pH 3.9; the molar ratios were 1:2 at pH 3.5 and 4.5, but these ratios were 1:1 at pH 5.0 and 6.0. The absorption peaks of malvidin-3-monoglucoside were shifted to shorter wavelengths in the visible range but to longer wavelengths in the UV range upon addition of various concentrations of cupric ions. The absorption peaks of petunidin-3-monoglucoside were shifted to shorter wavelength in both the UV and the visible light ranges upon addition of various concentrations of cupric ions. The infrared absorbancies of 3′-metboxy-apigeninidin-chloride-4′-methyl-ether at 11 to 14.5 μ disappeared upon the addition of Ca and Mg ions.

The thiamine, riboflavin, vitamin B6, vitamin B12, niacin, biotin, fo- late, pantothenate and vitamin C levels in several American wines were determined. Five types of white wine and eight types of red wine were examined. The levels of the eight B-vitamins were higher in the red wines than in the white. Nutritionally significant levels of riboflavin, vitamin B6 and niacin were found in the red wines. Folate levels of the wines were lower than reported in earlier studies. Statistical evaluation of the thiamine data indicated the presence of inhibition in these as- says.

To test whether the individual factor patterns of panelists and the panel factor pattern agreed, five grades of tea of the same type, ranging from low to high quality were studied. When a likelihood-ratio (LR) test and cluster analysis (CA) were applied to the 55-term correlation matrices of the seven individual panelists, according to the LR test only two of the matrices were homogeneous, but the CA test grouped all the matrices into the same cluster. The study demonstrated that the correlation matrices of the individual panelists or factor patterns themselves should be examined for agreement among panelists when factor analysis is used.

SUMMARY –Although temperatures occurring in nature are constantly fluctuating, virtually all research involving temperature effects on organisms has been carried out at constant temperatures. An investigation was made to determine the effect mild cycling of temperature has on certain species of bacteria. The effect of constant and cycled-up or cycled-down temperatures was determined for Pseudomonas fluorescens. A thermal gradient-bar proved to be a rapid, efficient method for determining these effects, affording a wide range of temperatures with only a few degrees difference between two consecutive temperatures. Cycling effects appeared to be dependent upon the organism and whether or not the temperature was above or below the optimum growth temperature. In general, the cycled-down growth responses appear to be greater than those for the cycled-up responses. At temperatures both above and below the optimum, the cycled-down organisms produced greater growth responses than the cycled-up organisms. The constant values are only a small amount greater than the cycled-down values.

Fourteen wines of various types were analyzed for 17 minerals. Two of the white wines and two of the red wines were experimental wines made from varietal grapes. The experimental wines were Chenin blanc, Sauvignon blanc, Cabernet Sauvignon and Zinfandel. Colbalt, cadmium, nickel and selenium contents were below levels of detectability of 0.3, 0.05, 0.3 and 0.02 ppm respectively, in all wines analyzed. Of the minerals measured, potassium sodium phosphorous, magnesium and calcium were found in greatest concentration. Higher sodium contents were noted in bulk produced, commercial wines than in the experimental wines. The K/Na ratio of the experimental white wines varied from 62.1–87.4 while the K/Na ratio of commercial white wines ranged from 9.6–16.5. Similar differences were noted when the K/Na ratios of experimental red wines were compared with commercial red wines.

The pH, total acidity, and buffering capacity of canned green pep percorns against increases and decreases in pH were determined. The mean pH of nonacidified, canned green peppercorns was 6.51. The total acidity was 0.048%, calculated as citric acid. The buffering capacity between the original pH of the peppercorns and pH 8.35 was 0.188 milliequivalents. To lower the pH to 4.4, from 219-247 mg citric acid per 100g till-in weight of peppercorns is required. Canned green peppercorns acidified to pH 4.0 retained much of the pungency and pepperiness of fresh green peppercorns.

Threshold values for ethyl caprylate in distilled water, 10% ethanol and corn oil were 0.15, 1.43 and 25.0 mg/l. For phenyl ethyl alcohol, the respective values were 0.175, 6.3 and 25.0. The threshold determinations for ethyl caprylate were made 1 yr apart with two different panels. Extreme-value analysis was applied to the first set of data to estimate the percent of individuals whose thresholds might be lower than the lowest threshold observed and this estimate was compared with the results of the second series of trials. There was moderately good agreement.