7 research outputs found
Application of Gas Chromatography-Olfactometry (GC-O) and Correlation with Sensory Analysis. Gaaskromatograaf-olfaktomeetri (GC-O) rakendusv\uf5imalused ja korreleerimine sensoorse anal\ufc\ufcsiga
Application of Gas Chromatography-Olfactometry (GC-O) and Correlation with Sensory Analysis. Gaaskromatograaf-olfaktomeetri (GC-O) rakendusv\uf5imalused ja korreleerimine sensoorse anal\ufc\ufcsiga
Characterization of odor-active compounds of various pea preparations by GC-MS, GC-O, and their correlation with sensory attributes
Pea preparations (flours, concentrates, and isolates) are increasingly used in plant-based products, but their characteristic odor is often causing problems. Advanced knowledge of the aroma profile of pea preparations could improve understanding of how pea-based ingredients affect sensory properties of foods.This study investigated the aroma profiles of different pea preparations using solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), and descriptive sensory analysis. The GC-MS analysis included MRM detection of methoxypyrazines, which significantly contribute to the flavor of pea preparations.More than 100 volatile compounds were identified in pea preparation samples by GC-MS, aldehydes being the main molecules, and 39 aroma-active compounds were registered by GC-O assessors. Sensory attributes of pea protein preparations were compared with analytical data to find the characteristic aroma-active compounds. Sensory panel evaluation showed noticeable differences between the pea preparations. Unsaturated aldehydes, which impart green odor, and methoxypyrazines, with pea-like and beany notes, enhance the sensory perception of green and pea-like characteristics in pea preparations. Methanethiol increased sulfur-like odor in pea protein isolate A. β-Damascenone had high modified frequency in pea protein isolate C, enhancing honey-like attributes. Methanethiol and β-damascenone were not reported previously as odor-active compounds in pea protein preparations
The Stability of Phenolic Compounds in Fruit, Berry, and Vegetable Purees Based on Accelerated Shelf-Life Testing Methodology
Evaluating the stability of polyphenols in fruit, berry, and vegetable purees helps to assess the quality of these products during storage. This study aimed to (1) monitor the stability of total phenolic content (TPC) in four-grain puree with banana and blueberry (FGBB), mango-carrot-sea buckthorn puree (MCB), and fruit and yogurt puree with biscuit (FYB); (2) study the effect of aluminum-layered vs. aluminum-free packaging on the changes in TPC; and (3) assess the suitability of accelerated shelf-life testing (ASLT) methodology to evaluate the stability of polyphenols. The samples were stored at 23 °C for 182, 274, 365, and 427 days. The corresponding time points during ASLT at 40 °C were 28, 42, 56, and 66 days, calculated using Q10 = 3. The TPC was determined with Folin–Ciocalteu method. The results revealed that the biggest decrease in TPC took place with high-pH FGBB, which contained fewer ingredients with bioactive compounds. Minor changes were seen in FYB and MCB, which had lower pH values, and contained a larger amount of ingredients that include polyphenols. In addition, the choice of packaging material did not affect the TPC decrease in each puree. Finally, it was concluded that the ASLT methodology is suitable for studying the TPC changes in such purees, but the corresponding Q10 factors may vary and should be determined based on the chemical profile and ingredient list of the product
The Composition, Physicochemical Properties, Antioxidant Activity, and Sensory Properties of Estonian Honeys
Thirty honey samples from different regions of Estonia were investigated to determine the chemical compositions, physicochemical properties, bioactive compounds, and sensory characteristics of typical honeys from a northern climate. The physicochemical parameters, such as electrical conductivity, moisture content, free acidity, hydroxymethylfurfural, diastase, and invertase activity were measured. The color was measured and expressed by L*-, a*-, and b*-coordinates. Sensory parameters were determined by using “fruity”, “floral”, “berry-like”, “herbal”, “woody”, “spicy”, “sweet”, and “animal-like” as the main odor and flavor attributes. The total polyphenol and flavonoid contents were in the range of 26.2–88.7 mg gallic acid equivalents (GAE) per 100 g and 1.9–6.4 mg quercetin equivalents (QE) per 100 g, respectively. The identified polyphenols showed the highest intensities of caffeic acid, coumaric acid, and abscisic acid and its derivatives. The protocatechuic acid intensity was highest in honeys containing traces of honeydew elements and of cinnamic acid and myricetin in heather honey. The water-soluble antioxidant values were 37.8–311.2 mg ascorbic acid equivalents (AAE) per 100 g and the lipid soluble antioxidant values were 14.4–60.7 mg Trolox equivalents (TE) per 100 g. The major amino acid in the analyzed honeys was proline, with variable values depending on the honey’s botanical source. Correlations were calculated based on the results obtained. It was revealed that the typical Estonian honey has floral, berry-like, sweet, and rather mild sensory characteristics. Most of the honeys lacked stronger spicy, woody, and animal-like attributes. The typical color of Estonian honey is quite light
Microbiological, chemical, and sensorial characterisation of commercially available plant-based yoghurt alternatives
Consumer demand for plant-based dairy alternatives has increased rapidly during the past few years and the market has been saturated with a wide variety of alternative products. The general aim of this study was to broaden the understanding of the composition and characteristics of currently commercially available plant-based yoghurt alternatives focusing especially on the content of live bacteria. The bacterial composition, including the content of live bacteria in yoghurt alternatives, was evaluated using metagenetic sequencing of the 16S rRNA gene amplicons in combination with the novel PMAxx treatment approach. The content of organic acids, sugars, and volatiles was measured, and descriptive sensory analysis was carried out to comprehensively describe the products. While the main ingredient (soya, oat, coconut, or lupin) determined the general characteristics of the product, significant differences were observed in both chemical and microbiological composition and sensorial attributes even among the yoghurt alternatives made from the same plant ingredient