Steam distillation process for flavor enhancement of milk coffee: Effects of condensation temperature on volatile compounds and flavor characteristics.

To enhance the flavor characteristics of milk coffee, steam distillation was applied to roasted ground coffee to obtain extracts that were then added to the hot water extract of the residue. The effects of different condensation temperatures for steam distillation on the volatile compounds of condensates and the flavor characteristics of the milk coffees prepared with each condensate were investigated. The volatile compounds were analyzed by gas chromatography/mass spectrometry, and principal component analysis (PCA) was performed on the mean peak areas of the volatiles that showed significant differences between the samples. The five types of milk coffees prepared with/without condensates were evaluated by consumer panelists using the check-all-that-apply question combined with the milk coffee flavor lexicon. The results showed that the concentration of volatile compounds tended to be higher in response to decreasing condensation temperature in steam distillation. The volatile compounds were grouped into four patterns based on their concentration in the condensates, which was affected by the volatility of the compounds and the duration of the condensation process in steam distillation. PCA clarified the characteristic volatile compounds that contribute to differences between the three condensates. The check-all-that-apply results indicated that the samples prepared with the condensates enhanced some specific coffee flavors, although acceptances for them were not enhanced. Implementing a steam distillation step in the milk coffee production process could lead to enhancing the coffee flavor strength of milk coffee products, and changing the condensation temperature for steam distillation was effective for providing different flavor characteristics of milk coffee. PRACTICAL APPLICATION: Changing the condensation temperature for steam distillation is effective in differentiating the flavor characteristics of milk coffee. Increasing the condensation temperature resulted in decreased concentrations of volatile compounds, which enhanced the milk and rich flavor. Decreasing the condensation temperature resulted in increased concentrations of volatile compounds, which provided a stronger coffee flavor to the milk coffee, possibly leading to a reduction in the use of coffee for milk coffee production. The check-all-that-apply question combined with the milk coffee flavor lexicon could effectively evaluate consumers' perceptions of the milk coffee flavor characteristics and their acceptances in a single survey.

Impact of 'free-from' and 'healthy choice' labeled versions of chocolate and coffee on temporal profile (multiple-intake TDS) and liking.

Product reformulation for obtaining "free-from" or "healthy choice" versions may confer significant changes in sensory characteristics which could not meet consumer expectations in terms of sensory perception. Therefore, this paper aims to evaluate the influence of formulations of different product categories on their dynamic sensory profile and consumer acceptability. A sensory panel of 23 semi-trained assessors evaluated two product categories, chocolate and milk coffee, using Temporal Dominance of Sensations (TDS) over three consecutive intakes/sips (multiple-intake TDS) on two replications. TDS allowed us to describe the dynamic profile of classic products over the three intakes and to identify differences in the sensory temporal profile compared to their 'healthier choice' reformulated versions. For the chocolate category, increasing the cocoa and the reduction of lactose content mainly influenced the dominance of sweetness, dairy, cocoa, crunchy and bitterness attributes. No sugar addition and absence of caffeine (decaffeinated version) in ready to drink milk coffee beverage modified temporal perception of sweetness, bitterness, coffee flavor and smoothness texture. Higher overall liking averages were associated with the dominant attributes of chocolate with a higher level of cacao and milk coffee decaffeinated. The obtained results of the present work suggest that the multiple-intake TDS technique can be applied for the evaluation of different food categories, helping to develop healthier products and predicting the liking.

A case report of Proteus syndrome (PS).

BACKGROUND: Proteus syndrome (PS) is an extremely rare disease characterized by excessive chimeric growth of cells, and progressive and irregular asymmetrical hyperplasia. CASE PRESENTATION: Herein, a PS case with atypical clinical features and syndromes was reported, to improve the understanding of the diagnosis and treatment of the disease. The case was a 3-year-and-11-month-old male child. He was admitted due to a primary diagnosis of McCune-Albright syndrome. After admission, the lesion samples from the milk coffee spots, and nodular thickening skin at hands and feet were subjected to genetic screening. Genetic testing results confirmed the diagnosis of PS. CONCLUSIONS: Based on the clinical manifestations, laboratory tests, imaging data, and literature reviewing, the etiology, diagnosis, treatment and prognosis of PS have been analyzed and discussed.

Effects of Manufacturing Processing Conditions on Retronasal-Aroma Odorants from a Milk Coffee Drink.

To develop a ready-to-drink (RTD) milk coffee that retains the original coffee flavor, the effects of manufacturing processing conditions on retronasal-aroma (RA) odorants were investigated by gas chromatography-olfactometry (CharmAnalysis™) using an RA simulator (RAS). Twenty-nine of 33 odorants detected in the RAS effluent (RAS odorants) were identified. The detected odorants were classified into 19 odor-description groups. The total odor intensity (charm value, CMV) of all coffee RAS odorants decreased approximately 68% following pH adjustment, whereas the total CMV increased 6% to 7% following ultra-high-temperature sterilization. The total CMV ratio (about 83%) of the milk coffee produced using a new blending-after-sterilization (BAS) process without pH adjustment of the coffee was greater than that (approximately 56%) prepared using a conventional blending-before-sterilization (BBS) process with pH adjustment. In BAS-processed milk coffees, the total CMV ratio (91%) with infusion (INF)-sterilized reconstituted milk (r-milk) was greater than that (83%) of plate (PLT)-sterilized r-milk. Principal component analysis of odor-description CMVs indicated that the effect of coffee pH adjustment on odor characteristics was greater than that of sterilization, that BAS and BBS samples differed, and that BAS milk coffee prepared using INF sterilization was more similar to homemade milk coffee (blending unsterilized coffee without pH adjustment with PLT-sterilized milk) than milk coffee prepared using PLT sterilization. In conclusion, the BAS process using INF sterilization is superior for manufacturing RTD milk coffee that retains odor characteristics similar to targeted homemade milk coffee. PRACTICAL APPLICATION: Ready-to-drink milk coffee beverages produced using conventional blending-before-sterilization methods do not retain their original coffee flavor following adjustment of the pH of the coffee during manufacturing. The use of newly developed blending-after-sterilization methods, by contrast, produces ready-to-drink milk coffee with an aroma more similar to that of homemade milk coffee, as demonstrated using an analytical system for characterizing food product aromas. The blending-after-sterilization process is now being used in Japan to produce ready-to-drink milk coffee beverages.

Effects of Processing Conditions During Manufacture on Retronasal-Aroma Compounds from a Milk Coffee Drink.

To develop a ready-to-drink (RTD) milk coffee retaining the original coffee flavor, the effects of processing conditions during manufacture on retronasal-arma (RA) compounds from the milk coffee were investigated by gas chromatography-mass spectrometry using an RA simulator (RAS). Thirteen of 46 detected compounds in the RAS effluent (RAS compounds) decreased significantly following pH adjustment of coffee (from pH 5.1 to 6.8) and 5 compounds increased. RAS compounds from coffee tended to decrease through the pH adjustment and subsequent sterilization. Significantly higher amounts of 13 RAS compounds were released from the milk coffee produced using a blending-after-sterilization (BAS) process without the pH adjustment than from that using a blending-before-sterilization (BBS) process with the pH adjustment. In BAS-processed milk coffee, significantly lower amounts of 8 high-volatility compounds and 1H-pyrrole were released from coffee containing infusion-sterilized (INF) milk than from coffee containing plate-sterilized (PLT) milk, whereas 3 low-volatility compounds were released significantly more from coffee using PLT milk. Principal component analysis revealed that the effect of the manufacturing process (BAS, BBS, or homemade (blending unsterilized coffee without pH adjustment with sterilized milk)) on milk coffee volatiles was larger than that of the sterilization method (INF or PLT) for milk, and that the sterilization method could result in different RAS volatile characteristics in BAS and homemade processes. In conclusion, a BAS process was found to be superior to a BBS process for the manufacture of an RTD milk coffee that retains volatile characteristics similar to that of a homemade milk coffee. PRACTICAL APPLICATION: Ready-to-drink (RTD) milk coffee manufactured using the conventional blending-before-sterilization process does not retain its original coffee flavor due to pH adjustment of the coffee during the process. The new blending-after-sterilization (BAS) process enabled the production of RTD milk coffee whose volatiles are closer to that of homemade milk coffee, as demonstrated by the results of RAS-GC-MS analysis. The BAS process has already been applied to the manufacture of RTD milk coffees in Japan.