Marco Alexander Van Den Berg

Background: There is a continuous demand to create new, superior sensory food experiences. In the food industry, yeast-derived flavor products (YPs) are often used as ingredients in foods to create new aromas and taste qualities that are appreciated by consumers. Methods: Chicken bouillon samples containing diverse YPs were chemically and sensorially characterized using statistical multivariate analyses. The sensory evaluation was performed using quantitative descriptive analysis (QDA) by trained panelists. Thirty-four sensory attributes were scored, including odor, flavor, mouthfeel, aftertaste and afterfeel. Untargeted metabolomic profiles were obtained using stir bar sorptive extraction (SBSE) coupled to GC-MS, RPLC-MS and targeted HILIC-MS. Results: In total, 261 volatiles were detected using GC-MS, from chemical groups of predominantly aldehydes, esters, pyrazines and ketones. Random Forest (RF) modeling revealed volatiles associated with roast odor (2-ethyl-5-methyl pyrazine, 2,3,5-trimethyl-6-isopentyl pyrazine) and chicken odor (2,4-nonadienal, 2,4-decadienal, 2-acetyl furan), which could be predicted by our combined model with R² > 0.5. In total, 2305 non-volatiles were detected for RPLC-MS and 34 for targeted HILIC-MS, where fructose-isoleucine and cyclo-leucine-proline were found to correlate with roast flavor and odor. Furthermore, a list of metabolites (glutamate, monophosphates, methionyl-leucine) was linked to umami-related flavor. This study describes a straightforward data-driven approach for studying foods with added YPs to identify flavor-impacting correlations between molecular composition and sensory perception. It also highlights limitations and preconditions for good prediction models. Overall, this study emphasizes a matrix-based approach for the prediction of food taste, which can be used to analyze foods for targeted flavor design or quality control.

Trained sensory panels are regularly used to rate food products but do not allow for data-driven approaches to steer food product development. This study evaluated the potential of a molecular-based strategy by analyzing 27 tomato soups that were enhanced with yeast-derived flavor products using a sensory panel as well as LC-MS and GC-MS profiling. These data sets were used to build prediction models for 26 different sensory attributes using partial least squares analysis. We found driving separation factors between the tomato soups and metabolites predicting different flavors. Many metabolites were putatively identified as dipeptides and sulfur-containing modified amino acids, which are scientifically described as related to umami or having “garlic-like” and “onion-like” attributes. Proposed identities of high-impact sensory markers (methionyl-proline and asparagine-leucine) were verified using MS/MS. The overall results highlighted the strength of combining sensory data and metabolomics platforms to find new information related to flavor perception in a complex food matrix.

Nowadays, a growing offering of plant-based meat alternatives is available in the food market. Technologically, these products are produced through high-moisture shear technology. Process settings and material composition have a significant impact on the physicochemical characteristics of the final products. Throughout the process, the unfolded protein chains may be reduced, or associate in larger structures, creating rearrangement and cross-linking during the cooling stage. Generally, soy and pea proteins are the most used ingredients in plant-based meat analogues. Nevertheless, these proteins have shown poorer results with respect to the typical fibrousness and juiciness found in real meat. To address this limitation, wheat gluten is often incorporated into the formulations. This literature review highlights the key role of wheat gluten in creating products with higher anisotropy. The generation of new disulfide bonds after the addition of wheat gluten is critical to achieve the sought-after fibrous texture, whereas its incompatibility with the other protein phase present in the system is critical for the structuring process. However, allergenicity problems related to wheat gluten require alternatives, hence an evaluation of underutilized plant-based proteins has been carried out to identify those that potentially can imitate wheat gluten behavior during high-moisture shear processing.

To increase the appeal of plant protein–based meat analogs, further progress needs to be made in their sensory perception. Given the limited number of studies on meat analogs, this review focuses on structure, oral processing, and sensory perception of meat and subsequently translates the insights to meat analogs. An extensive number of publications has built the current understanding of meat mechanical and structural properties, but inconsistencies concerning terminology and methodology execution as well as the wide variety in terms of natural origin limit solid conclusions about the control parameters for oral processing and sensory perception. Consumer-relevant textural aspects such as tenderness and juiciness are not directly correlated to single structural features but depend on an interplay of multiple factors and thus require a holistic approach. We discuss the differences in mastication and disintegration of meat and meat analogs and provide an outlook toward converting skeptical consumers into returning customers.

A time‐discrete temporal check‐all‐that‐apply (TCATA) data analysis method was implemented and applied to two different commercial use cases: (I) exploration of the dynamic sensory effects evoked by sweetened yogurt, and (II) a dynamic flavor profile comparison of nutritionally fortified gummy bears. The purpose of the first study was to explore opportunities for calorie reduction while maintaining the original dynamic sensory profile. The purpose of the second study was to benchmark commercially available fortified candy for (after)taste. The resulting time‐discrete data were fitted with Poisson regression allowing means for computing confidence intervals for each discrete time bucket. A roughness penalty was added to impose smoothness to the fitted TCATA profiles. Both studies demonstrated improved visualization and revealed underlying dynamic sensory insights which were hidden in conventional TCATA profiles based on the primary data.Practical Applications: Temporal sensory effects—determining onset, intensity, and duration (aka lingering) of various attributes—are key for consumer acceptance of new food products. However, cross‐modal interactions and the complexity of sensory attributes can limit the discrimination between different products. This study established a generic toolbox to process raw temporal (i.e., TCATA) data and improve visualization and discrimination. These results help to quantify and identify possible methodologies to improve ingredient applications for healthy foods (e.g., sugar reduction, nutrient fortification). The tool is available for analyzing TCATA data acquired with commercially available sensory data acquisition software products like EyeQuestion, FIZZ, and Compusense.

Dihydro analogues are known byproducts of the fermentative production of statins and cannot be detected with existing pharmacopoeia analysis methods. We detected dihydropravastatin in most commercial formulations of pravastatin with LC-MS, in some cases in levels requiring identification. In fermentation broth samples of the single step production of pravastatin, we detected and identified for the first time 4a,5-dihydropravastatin, and confirmed that after several recrystallization steps this impurity can be fully removed from the pravastatin powder.

Lytic polysaccharide monooxygenases (LPMOs) have sparked a lot of research regarding their fascinating mode-of-action. Particularly, their boosting effect on top of the well-known cellulolytic enzymes in lignocellulosic hydrolysis makes them industrially relevant targets. As more characteristics of LPMO and its key role have been elucidated, the need for fast and reliable methods to assess its activity have become clear. Several aspects such as its co-substrates, electron donors, inhibiting factors, and the inhomogeneity of lignocellulose had to be considered during experimental design and data interpretation, as they can impact and often hamper outcomes. This review provides an overview of the currently available methods to measure LPMO activity, including their potential and limitations, and it is illustrated with practical examples.

Background: Non-digestible carbohydrates are added to infant formula to mimic the effects of human milk oligosaccharide by acting as prebiotics and stimulating the immune system. Although not yet used in infant formulas, β-glucans are known to have beneficial health effects, and are therefore of potential interest for supplementation. Methods and results: We investigated the in vitro fermentation of native and endo-1,3(4)-β-glucanase-treated oat β-glucan using pooled fecal inocula of 2- and 8-week-old infants. While native oat β-glucan was not utilized, both inocula specifically utilized oat β-glucan oligomers containing β(1→4)-linkages formed upon enzyme treatment. The fermentation rate was highest in the fecal microbiota of 2-week-old infants, and correlated with a high lactate production. Fermentation of media supplemented with native and enzyme-treated oat β-glucans increased the relative abundance of Enterococcus and attenuated pro-inflammatory cytokine production (IL-1β, IL-6, TNFα) in immature dendritic cells. This attenuating effect was more pronounced after enzyme treatment. This attenuation might result from the enhanced ability of fermented oat β-glucan to stimulate Dectin-1 receptors. Conclusion: Our findings demonstrate that endo-1,3(4)-β-glucanase treatment enhances the fermentability of oat β-glucan and attenuates pro-inflammatory responses. Hence, this study shows that especially enzyme-treated oat β-glucans have a high potential for supplementation of infant formula.

Significance: Statins are successful widely used drugs that decrease the risk of coronary heart disease and strokes by lowering cholesterol levels. They selectively inhibit the key regulatory enzyme of the cholesterol synthesis pathway, thus lowering levels of plasma LDL (bad) cholesterol. Pravastatin is one of the leading and most effective statins, derived from the natural product compactin. However, pravastatin production involves a costly dual-step fermentation and biotransformation process. Here we present a single-step fermentative method for production of the active drug pravastatin. Reprogramming of the antibiotics-producing fungus Penicillium chrysogenum , with discovery and engineering of an enzyme involved in the hydroxylation of compactin, enables high level fermentation of the correct form of pravastatin to facilitate efficient industrial-scale statin drug production.