Garlic contains sulfur volatiles that cause a bad odor after consumption. The objective of this study was to understand how yogurt and its components cause deodorization. Raw and fried garlic samples ...were mixed with various treatments and measurements of volatiles were conducted using a selected-ion flow-tube mass spectrometer. Frying garlic significantly reduced almost all sulfur volatile compounds. Raw garlic was deodorized more than fried garlic by all of the treatments. Fat, protein and water significantly reduced the concentration of sulfur-based volatiles in garlic. At the same concentration, either fat or protein produced higher deodorization, depending on the hydrophobicity of the volatile. Whey protein, casein and their complex all caused deodorization. Increasing the pH to 7 or heating changed the structure of the proteins and decreased the deodorization of the volatiles, showing the importance of proteins for deodorization. As the quantity of fat increased, the deodorization of the volatiles also increased. Foods with higher fat or protein content can be formulated to offer a potential solution to reduce the unpleasant odor associated with garlic consumption.
Cocoa beans were alkalized before or after roasting and made into cocoa liquor before analyzing by SIFT-MS. In both alkalized-before-roasting and alkalized-after-roasting samples, there were ...significantly higher concentrations of alkylpyrazines for the samples with pH above 7 than pH below 7. At pH 8, the concentrations of 2,3-, 2,5-, and 2,6-dimethylpyrazine (DMP), 2,3,5-trimethylpyrazine (TrMP), 2,3,5,6-tetramethylpyrazine (TMP), and 2,3-diethyl-5-methylpyrazine (EMP) in the samples alkalized-before-roasting were higher than those in the samples alkalized-after-roasting. Volatiles increased under conditions that promoted the Maillard reaction. The partition coefficient was not significantly affected by pH from 5.2 to 8. The ratios of TrMP/DMP and DMP/TMP increased while the ratio of TMP/TrMP decreased as the pH increased. The concentrations of Strecker aldehydes and other volatiles followed a similar pattern as that of the alkylpyrazines. High pH favors the production of alkylpyrazines and Strecker aldehydes. Practical Applications: Cocoa beans alkalized-before-roasting had higher levels of many important chocolate aroma volatiles than those alkalized-after-roasting. Thus, alkalizing before roasting should produce a stronger cocoa aroma. The higher the pH, the higher the concentrations of these important volatiles. There was little change in volatile concentration at acid pH. Above pH 7, volatile levels increased rapidly with increasing pH. To maintain the recommended ratio of tetramethylpyrazine to trimethylpyrazine, a longer roasting time or higher temperature is needed for cocoa liquor with a pH below 6.5, while a shorter roasting time or lower temperature is needed for cocoa liquor with a pH above 7.
: Microwave, oven, and oil roasting of almonds were used to promote almond flavor and color formation. Raw pasteurized almonds were roasted in a microwave for 1 to 3 min, in an oven at 177 °C for 5, ...10, 15, and 20 min; and at 135 and 163 °C for 20 min, and in oil at 135, 163, and 177 °C for 5 min and 177 °C for 10 min. Volatile compounds were quantified in the headspace of ground almonds, both raw and roasted, by selected ion flow tube mass spectrometry. Strong correlations were found between L value, chroma, and 5‐(hydroxy methyl)‐2‐ furfural; and were independent of roasting method. Raw almonds had lower concentrations of most volatiles than roasted almonds. Conditions that produced color equivalent to commercial samples were 2 min in the microwave, 5 min at 177 °C in the oven, and 5 min at 135 °C in oil. Microwave heating produced higher levels of most volatiles than oven and oil roasting at commercial color. Sensory evaluation indicated that microwave‐roasted almonds had the strongest aroma and were the most preferred. Oil‐roasted almonds showed significantly lower levels of volatiles than other methods, likely due to loss of these volatiles into the oil. Alcohols such as benzyl alcohols and strecker aldehydes including benzaldehyde and methional were at higher concentrations than other volatiles in roasted almonds. The oxidation of lipids to form alkanals such as nonanal and degradation of sugars to form furan type compounds was also observed. The Maillard reaction contributed to the formation of more of the total volatiles in almonds than the lipid oxidation reaction.
Practical Application: The level of 5‐(hydroxy methyl)‐2‐ furfural (HMF), color, volatile profile, and sensory perception can be used to develop the best roasting method, time, and temperature for almonds. The rate of color development and the production of volatiles differ under different roasting conditions. Based on the color, volatile, and sensory assessments of the 3 almonds, the use of microwave technology as a process for roasting almonds reduces processing time and leads to an almond product with better flavor than oven or oil roasting.
The ability of foods and beverages to reduce allyl methyl disulfide, diallyl disulfide, allyl mercaptan, and allyl methyl sulfide on human breath after consumption of raw garlic was examined. The ...treatments were consumed immediately following raw garlic consumption for breath measurements, or were blended with garlic prior to headspace measurements. Measurements were done using a selected ion flow tube‐mass spectrometer. Chlorophyllin treatment demonstrated no deodorization in comparison to the control. Successful treatments may be due to enzymatic, polyphenolic, or acid deodorization. Enzymatic deodorization involved oxidation of polyphenolic compounds by enzymes, with the oxidized polyphenols causing deodorization. This was the probable mechanism in raw apple, parsley, spinach, and mint treatments. Polyphenolic deodorization involved deodorization by polyphenolic compounds without enzymatic activity. This probably occurred for microwaved apple, green tea, and lemon juice treatments. When pH is below 3.6, the enzyme alliinase is inactivated, which causes a reduction in volatile formation. This was demonstrated in pH‐adjusted headspace measurements. However, the mechanism for volatile reduction on human breath (after volatile formation) is unclear, and may have occurred in soft drink and lemon juice breath treatments. Whey protein was not an effective garlic breath deodorant and had no enzymatic activity, polyphenolic compounds, or acidity. Headspace concentrations did not correlate well to breath treatments.
Commercial kefir was recently found to be effective in curing recurrent Clostridioides difficile infection when consumed alongside antibiotic treatment. However, kefir products have limited ...acceptance among Western consumers due to their characteristic flavor and texture. Plain, unsweetened commercial kefir with 1% milkfat was subjected to vacuum evaporation and freeze‐drying processes to assess the effect on volatile organic compound concentration, sensory quality, and microbial viability. Vacuum evaporation and freeze‐drying both significantly decreased the concentration of 26 out of 27 volatiles in the kefir (p < 0.05), by an average of 61%. Vacuum evaporation exhibited an apparent greater reduction than freeze‐drying in the concentrations of the ketones and aldehydes, while freeze‐drying showed a more noticeable reduction in the concentrations of the acids, alcohols, and esters. While lowering the concentration of volatiles did not significantly improve the average consumer acceptance of commercial kefir, both treatments showed differences in the range of acceptability responses. Both treatments also produced a small but significant reduction in the concentrations of Lactobacillus and Lactococcus species present.
Consumption of garlic leads to the persistence of “garlic breath” due to the presence of malodorous sulfur volatiles which may persist for as long as 24 h. Therefore, the purpose of this study is to ...investigate the effect of yogurt and its components on the deodorization of garlic sulfur volatiles in breath and study the roles of these components in deodorization. Raw garlic was consumed with different treatments and at different times for breath analysis. Different components were mixed with the garlic for headspace analysis. Volatiles were measured using selected-ion flow-tube mass spectrometry. Consuming yogurt at the same time as garlic was more effective than consuming it before or after. Yogurt was the most effective at deodorization, followed by the emulsion, then protein or fat alone. Decreasing the pH of protein solutions increased deodorization because changes to the structure of the proteins exposed more binding sites for the volatiles, while decreasing the pH of water or fat had no effect on deodorization. Whey protein deodorized better than casein due to the presence of more cysteine binding sites for volatiles. This study proposes that the fat, protein, microbial culture, and water in yogurt have synergistic effects on the deodorization of garlic volatiles. This study’s findings can help in the development of novel products targeting sulfur volatiles, with broad applications for mitigating malodors produced by garlic.
Sunflower seeds are a popular snack in many countries, such as the United States, China, and Spain. Sunflower seeds are typically roasted to create desirable aromas before being eaten. The desirable ...aromas are created by the Maillard and lipid oxidation reactions. Increasing the volatiles created by these reactions can create a more desirable product, increasing consumer acceptance of sunflower seeds. Seeds were soaked in solutions at pH 4, 7, and 9 and with added glucose, fructose, whey protein isolate, or whey protein concentrate before roasting. The resulting seeds were evaluated by selected-ion flow tube mass spectrometry to determine the volatile concentrations and by an untrained panel of consumers to determine acceptability. Increasing the pH increased the pyrazines but did not affect other volatiles. Adding reducing sugars or whey protein increased most volatiles. The fructose increased dimethylpyrazines, 2-methylpyrazine, and trimethylpyrazine concentrations more than glucose. However, the glucose increased furfural concentration more than fructose. The whey protein concentrate increased volatile levels more than any other treatment. The total Maillard volatiles and Browning index were increased by the same treatments. Sensory indicated that fructose increased desirable aroma the most, followed by whey protein treatments, and both were liked more than the pH 7 control. Optimizing roasting conditions by increasing the pH and reducing sugar and protein content can favor the Maillard reaction conditions, increasing the positive aromas associated with roasted sunflower seeds.
Roasted peanut color and volatiles were evaluated for different time and temperature combinations of roasting. Raw peanuts were oven roasted at 135 to 204 °C, microwave roasted for 1 to 3 min, or ...combination roasted by microwave and oven roasting for various times and temperatures. Volatiles were measured using selected ion flow tube mass spectrometry. L* values were used to categorize peanuts as under‐roasted, ideally roasted, and over‐roasted. The total roasting time in order to achieve ideal color was not shortened by most of the combination treatments compared to their oven roasted equivalents. Oven before microwave roasting compared to the reverse was found to significantly increase the L* value. Peanuts with the same color had different volatile levels. Hexanal concentrations decreased then increased with roasting. Pyrazine levels increased as roasting time increased, although oven at 177 °C treatments had the highest and microwave treatments had the lowest levels. Volatile levels generally increased as roasting time or temperature increased. Oven 177 °C for 15 min generally had the highest level of volatiles among the roasting treatments tested. Soft independent modeling of class analogies based on volatile levels showed that raw peanuts were the most different, commercial samples were the most similar to each other, and oven, microwave, and combination roasting were all similar in volatile profile.
To investigate the kinetics of furan formation during pasteurization in soy sauce, the furan concentration in five samples was determined with Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) after ...hot water bath heating at 30, 50, 70, or 80 °C for 10 min to 7.25 h, respectively. The furan concentrations in soy sauce were 12–215 ng/mL. Furan formation in soy sauce is a zero-order reaction and the reaction rate constants were 3.71 × 10−9 mol/L.h for Pearl River Bridge brand (PRBB) soy sauce and 6.99 × 10−9 mol/Lh for Koon Chun brand (KCSB) at 80 °C respectively. In addition, by the Arrhenius equation and active complex theory, the apparent activation energy (Ea), enthalpy (ΔH≠θ) and entropy (ΔS≠θ) were summarized as the equations, lnk = −77237/RT + 6.61 and lnk/T = −74522/RT − 0.18 for PRBB, and lnk = −72018/RT+5.35 and lnk/T = −63301/RT + 0.08 for KCSB, where k is the rate constant, T is the absolute temperature and R is the universal gas constant. Ea, ΔH≠θ and ΔS≠θ for PRBB are 77.237 kJ/mol, 74.522 kJ/mol, and −199.01 J/K·mol. Ea, ΔH≠θ and ΔS≠θ for KCSB are 72.018 kJ/mol, 63.301 kJ/mol, and −209.72 J/K·mol. These results can be used to calculate or predict furan formation in soy sauce during pasteurization.
•The kinetic parameters of soy sauce are reported, including the apparent activation energy (Ea), enthalpy (ΔH≠θ) and entropy (ΔS≠θ).•Furan formation in soy sauce is a zero-order reaction.•The Arrhenius equation for furan formation during pasteurization for two brands of sauce are reported.•Furan formation in soy sauce during pasteurization can be predicted based on these results.•A simple, fast and accurate method for determination of furan in food is presented.
Tomatoes are typically not peeled before being made into juice but the peels contain enzymes that affect the odor, flavor, and viscosity of the juice. The peels are removed in the finisher, but their ...presence during the break process may affect quality. Juice was processed from peeled and unpeeled tomatoes using hot or cold break. The juices were pasteurized by high temperature short time (HTST), low temperature long time (LTLT), or with a retort. The control samples were treated with 10% calcium chloride to stop enzymatic activity in the juice. Sauce was made from juice and the tomato products were analyzed for volatiles, color, viscosity, and by sensory. Cold break juice made with peel contained higher levels of some lipoxygenase‐, carotenoid‐, and amino acid–derived volatiles, than the juice made without peel. Because of the lack of enzyme activity, hot break juices had lower levels of these volatiles and there was no significant difference between hot break juices made with and without peel. CaCl₂‐treated and HTST juice had higher levels of most of the volatiles than LTLT, including the lipoxygenase‐derived volatiles. The presence of peel produced a significant decrease in the viscosity of the cold break juice and sauce. There was no significant difference in the hue angle, total soluble solids, pH, titratable acidity, and vitamin C for most of the treatments. The texture, flavor, and overall liking of cold break juice made without peel were preferred over cold break juice made with peel whereas the color was less preferred. Between the sauces no significant differences in preference were obtained.
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