Comparing the aromatic profile of seven unheated edible insect species.

Insects and insect-based products have gained increasing interest as human food because of their many technological, nutritional and environmental advantages, but they are still rejected by many Western consumers. Analytical knowledge of flavour compounds could contribute to enhancing product attractiveness to consumers. Therefore, the goal of this study was to examine the volatile compound profiles of 7 unheated insects: Zophobas morio (ZM), Tenebrio molitor (TM), Locusta migratoria (LM), Galleria mellonella (GM), Blaptica dubia (BD), Alphitobius diaperinus (ALD) and Acheta domesticus (ACD). A total of 67 compounds were identified. Carboxylic acids were predominant in ALD, BD, GM, TM and ZM, while ketones were the major family in ACD and linear hydrocarbons in LM. ZM contained the highest number of unpleasant odour compounds, including indole, also present in BD and GM, which is characterised by a low detection threshold.

Improving the Aromatic Profile of Plant-Based Meat Alternatives: Effect of Myoglobin Addition on Volatiles.

Market demand for palatable plant-based meat alternatives is on the rise. One of the challenges is formulating products with sensorial characteristics similar to conventional meat. In this study, the effect of myoglobin on the aromatic profile of plant-based meat alternatives was assessed. Plant-based burgers were made with soy-textured protein, supplemented with three levels of myoglobin (0, 0.5 and 1.0%, the latter two mimicking endogenous myoglobin levels in meat), and grilled for 12 min at 250 °C. To evaluate the aromatic profile of the compounds, raw and grilled samples were subjected to headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). Principal component analysis (PCA) analysis was then performed to visualize the interaction between grilling and myoglobin addition, and the effect exerted on the resulting aromatic profile. Myoglobin significantly affected several classes of volatile compounds, either by itself or in conjunction with grilling. A notable increase in aldehydes and a decrease in hydrocarbons were noted after adding myoglobin. As expected, an increase in pyrazines was observed after grilling. The results suggest myoglobin positively influences the aromatic profile of plant-based meat alternatives, contributing to a profile closer to the one of conventional meat.

Effect of Lactic Acid Fermentation on Volatile Compounds and Sensory Characteristics of Mango (Mangifera indica) Juices.

Fermentation is a sustainable bio-preservation technique that can improve the organoleptic quality of fruit juices. Mango juices were fermented by monoculture strains of Lactiplantibacillus plantarum subsp. plantarum (MLP), Lacticaseibacillus rhamnosus (MLR), Lacticaseibacillus casei (MLC), Levilactobacillus brevis (MLB), and Pediococcus pentosaceus (MPP). Volatile compounds were sorbed using headspace solid phase microextraction, separated, and identified with gas chromatography-mass spectrometry. Forty-four (44) volatile compounds were identified. The control, MPP, and MLB had higher amounts of ethyl acetate, ethyl butyrate, 2-hexenal, 2,6-nonadienal, 2,2-dimethylpropanal, ß-selinene, γ-gurjunene, α-copaene, and δ-cadinene, while MLC, MLP, and MLR had higher amounts of 2,3-butanedione and a cyclic hydrocarbon derivate. Consumers (n = 80) assessed their overall liking and characterized sensory attributes (appearance, color, aroma, flavor, consistency, acidity, and sweetness) using check-all-that-apply, and penalty analysis (just-about-right). Overall liking was associated with 'mango color', 'pulp', 'mango aroma', 'sweet', 'natural taste', and 'mango flavor' that described the control, MLB, MLC and MPP. Juices MLR and MLP were described as 'bitter', 'sour', 'aftertaste', and 'off-flavor'. Multivariate analysis revealed relationships between the volatile compounds, mango juices fermented by different lactic acid bacteria, and sensory characteristics. Thus, the type of lactic acid bacteria strains determined the volatile and sensory profile of mango juices.

Effect of lactic acid fermentation of watermelon juice on its sensory acceptability and volatile compounds.

Fermentation increases food shelf-life but is characterized by changes that affect product's perception. Watermelon juice was fermented with Lactobacillus plantarum (WJ-LP), L. rhamnosus (WJ-LR), L. casei (WJ-LC), L. brevis (WJ-LB) and Pediococcus pentosaceus (WJ-PP). Their sensory characteristics and volatile compounds were investigated by consumers and Headspace Solid Phase Microextraction integrated with Gas Chromatography-Mass Spectrometry, respectively. WJ-PP and WJ-LB were most liked and perceived with 'watermelon-flavor', 'natural taste', 'sweet' and 'watermelon-color' while WJ-LC, WJ-LP and WJ-LR were least liked and perceived as 'sour', 'bitter', 'off-flavor', 'aftertaste' and 'intense-flavor'. Fifty-four volatiles were identified. After fermentation, alcohols, ketones, monoterpenes, acids, and furans increased while aldehydes and alkanes decreased. Lactic acid fermentation introduced 4-decanone and 2,3-butanedione in WJ-LB, WJ-LC, WJ-LP and WJ-LR, however, heptanal, 2-heptenal, 2,6-nonadienal, 2-decenal, and 2,4-decadienal in WJ-LC, heptanal, 2-hexenal, 2-heptenal, 2,6-nonadienal, 2-decenal and octanal in WJ-LR and 2,6-dimethyl-2,6-octadiene in WJ-LP disappeared. Juice sensory profiles were associated with their volatile compounds.

Impact of Nannochloropsis sp. dosage form on the oxidative stability of n-3 LC-PUFA enriched tomato purees.

Microalgae are a sustainable alternative source of n-3 LC-PUFA that can be incorporated into the food chain either via the incorporation of the (intact or disrupted) biomass or by the incorporation of the oil extracted from the biomass. However, the impact of the dosage form on the enrichment of food products with n-3 LC-PUFA and their oxidative stability has never been described before. This study aims to contribute more insight on the impact of the dosage form of the photoautotrophic microalga Nannochloropsis in enriched tomato puree. Three different dosage forms of Nannochloropsis were compared to commercial fish oil and analyzed for their amount of n-3 LC-PUFA, lipid oxidation products, antioxidants and free fatty acids. Tomato purees supplemented with dosage forms derived from Nannochloropsis showed higher oxidative stability than those supplemented with commercial fish oil. The highest oxidative stability was observed for purees supplemented with Nannochloropsis biomass irrespective of whether it was pre-disrupted.