Volatile aroma compounds of sugarcane molasses as affected by spray drying at low and high temperature

Value-added product from sugarcane molasses: Conversion of sugarcane molasses to non-caloric sweetener for applications in food and pharmaceutical industries

Molasses is a by-product from sugarcane processing industries that contains some useful natural compounds. This paper proposes a method to produce sucralose, a non-caloric sweetener, from sugarcane molasses. In the first step, sugarcane molasses was converted to dried molasses powder using the low-temperature spray drying process in order to preserve natural compounds. Response surface methodology and artificial neural network were used to determine the experimental condition for maximal bioactive compounds content and antioxidant activity. Dried molasses powder could be produced with maximal values of sucrose yield, total phenolic content, total flavonoid content and antioxidant activity. In the final step, sucralose was derived from dried molasses powder. The yield of molasses-derived sucralose obtained from the proposed method was 0.628±0.01 g/g dried molasses powder with the purity of 99.95±0.02 %. The proposed method paves the way to convert sugarcane molasses to a non-caloric sweetener for applications in food and pharmaceutical industries.

Identification of differential volatile and non-volatile compounds in coffee leaves prepared from different tea processing steps using HS-SPME/GC-MS and HPLC-Orbitrap-MS/MS and investigation of the binding mechanism of key phytochemicals with olfactory and taste receptors using molecular docking

Tea processing steps affected the proximate composition, enzyme activity and bioactivity of coffee leaves; however, the effects of different tea processing steps on the volatiles, non-volatiles, color, and sensory characteristics of coffee leaves have yet been demonstrated. Here the dynamic changes of volatile and non-volatile compounds in different tea processing steps were investigated using HS-SPME/GC-MS and HPLC-Orbitrap-MS/MS, respectively. A total of 53 differential volatiles (alcohol, aldehyde, ester, hydrocarbon, ketone, oxygen heterocyclic compounds, phenol, and sulfur compounds) and 50 differential non-volatiles (xanthone, flavonoid, organic acid, amino acid, organic amine, alkaloid, aldehyde, and purine et al.) were identified in coffee leaves prepared from different processing steps. Kill-green, fermentation, and drying steps significantly influenced the volatiles; however, kill-green, rolling, and drying steps significantly affected the color of coffee leaves and their hot water infusion. The coffee leaf tea that was prepared without the kill-green process was found to have a more pleasant taste as compared to the tea that was prepared with the kill-green process. This can be attributed to the fact that the former contained lower levels of flavonoids, chlorogenic acid, and epicatechin, but had higher levels of floral, sweet, and rose-like aroma compounds. The binding interactions between the key differential volatile and non-volatile compounds and the olfactory and taste receptors were also investigated. The key differential volatiles, pentadecanal and methyl salicylate generate fresh and floral odors by activating olfactory receptors, OR5M3 and OR1G1, respectively. Epicatechin showed a high affinity to the bitter receptors, including T2R16, T2R14, and T2R46. Since the specific content of differential compounds in different samples varies greatly, the dose-effect and structure-function relationships of these key compounds and the molecular mechanism of the odor and taste of coffee leaf tea need to be further studied.

Effects of Roasting Sweet Potato (Ipomoea batatas L. Lam.): Quality, Volatile Compound Composition, and Sensory Evaluation

Roasting can increase the Maillard reaction and caramelization of sweet potatoes to create an attractive appearance, color, aroma, and taste, and is rapidly increasing in the commercial market. This study mainly analyzed the influence of roasting sweet potatoes, with and without the peel, on sweet potato quality and flavor characteristics combined with sensory qualities. The results showed that the a* value (1.65-8.10), browning degree (58.30-108.91), total acidity (0.14-0.21 g/100 g, DW), and maltose content (0.00-46.16 g/100 g, DW) of roasted sweet potatoes increased with roasting time. A total of 46 volatile compounds were detected and 2-furanmethanol, furfural, and maltol were identified as the main sources of the aroma of roasted sweet potatoes. A sensory evaluation based on a comprehensive nine-point acceptance test and descriptive analysis showed that roasting for 1 to 2 h resulted in the highest acceptance score (6.20-6.65), including a golden-yellow color, sweet taste, and fibrous texture. The sweet potatoes became brown after roasting for 2.5 to 3 h and gained a burnt and sour taste, which reduced the acceptance score (4.65-5.75). These results can provide a reference for increased quality in the food industry production of roasted sweet potatoes.