Characterization of texturized meat analogues containing native lupin flour and lupin protein concentrate/isolate

Lupin is a nutritious, yet undervalued grain used as a fodder and food crop. In the present study, native lupin flour (LF), lupin protein concentrate (LPC), and lupin protein isolate (LPI) were combined (70% LPI:LPC blend ratios [30:70, 50:50, and 70:30] and 30% LF constant fraction), extruded at high moisture (45-55%), and shaped with a long cooling die (800 mm) to obtain texturized meat analogues (TMAs) with fibrous structures. The characteristics of TMAs (e.g., hardness, water hydration capacity) depended heavily on water content, blend ratios (LPI:LPC), and to a lesser extent, the long cooling die temperature. Color changes (i.e., L*, b*) were mostly attributed to variations in blend ratios (LPI:LPC). Microstructure analysis showed that TMAs with higher water content (55%) were more likely to have thinner walls and smaller void thickness. Fluorescence imagery revealed that TMAs with lower LPI content presented more homogeneous structures. These findings show that reasonable amounts (30% d.m.) of native lupin flour can be incorporated into meat analogues by maintaining a sufficiently high protein content (>50% d.m.) to trigger the formation of fibrous structures.

Functionality of oat fiber concentrate and faba bean protein concentrate in plant-based substitutes for minced meat

Oat has been recognized for its health-promoting fiber, β-glucan, while protein-rich faba bean has remained underutilized in Nordic countries despite its good nutritional quality. This research investigated the functionality of oat fiber concentrate and faba bean protein concentrate in plant-based substitutes for minced meat (SMs). The resulting product aimed at mimicking the mechanical and physicochemical characteristics of beef minced meat (BM) and its applications (i.e., fried and burger patty). In this regard, the mechanical properties (e.g., chewiness, Young's modulus) of original/fried SMs were comparable to or higher than those of original/fried BM. SM patties (45% SMs) were structurally weaker than beef burger patties (100% BM). The rheological analysis showed that the presence of oat fiber concentrate increased the gel-like properties of the blend, which correlated with the overall strength of original SMs (e.g., Young's modulus). The results suggested that SMs could be used as BM for the preparation of vegetarian meat-like products.

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SMs containing up to 36% dietary fiber—the half being β-glucan—were obtained.

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Oat-fiber- and faba-bean-protein-concentrate were successfully combined into SMs.

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SMs were mechanically comparable to beef minced meat.

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Patties containing SMs were softer than beef patties.

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Oat fiber concentrate increased the gel-like properties of the blend.

Quantification of Wheat, Rye, and Barley Gluten in Oat and Oat Products by ELISA RIDASCREEN® Total Gluten: Collaborative Study, First Action 2018.15

Background: Since its introduction to the analytical community, the R5 method to quantify gluten led to a strong improvement of the situation for the food industry and celiac patients. During recent years, some questions arose on the use of the Codex Alimentarius factor of two to convert from prolamins to gluten, an overestimation of rye and barley, inadequate detection of glutelins, and the inhomogeneous distribution of gluten in oats. These limitations of the R5 method, especially when measuring oat samples, led to AOAC Standard Method Performance Requirement (SMPR®) 2017.021, which was approved by stakeholders in 2017. Objective: We present a collaborative study of a method for the quantitative analysis of wheat, rye, and barley gluten in oat and oat products using a sandwich ELISA that is based on four different monoclonal antibodies including the R5 monoclonal anitbody. Methods: The sandwich ELISA detects intact gliadins and related prolamins from rye and barley, high-molecular-weight (HMW) glutenin subunits (GS) from wheat, HMW secalins from rye, and low-molecular-weight (LMW) GS from wheat. It does not detect D-hordeins from barley. Samples are extracted by Cocktail solution, subsequently followed by 80% ethanol, and analyzed within 50 min. Results: The measurement range is between 5 and 80 mg/kg gluten using a calibrator made out of a gluten extract from four different wheat cultivars. The results of the collaborative test with 19 participating laboratories showed recoveries ranging from 99 to 137% for all three grain sources. Relative reproducibility SDs for samples >10 mg/kg gluten ranged from 10 to 53%. Conclusions: The collaborative study results confirmed that the method is accurate and suitable to measure gluten from all three grain sources and has demonstrated performance on oat matrices, which meets the criteria as specified in SMPR 2017.021. Data from in-house validation experiments are available as Annex B to this publication.

The effect of beta-glucan on the glycemic and insulin index

OBJECTIVE

To determine the effects of oat products with increasing beta-glucan content on the glycemic (GI) and insulin indexes (II) of oat products, and to establish the effect of physical properties of beta-glucan on these physiological responses.

DESIGN

Test group (n=10) randomly attended to three glucose tolerance tests and glycemic response tests for four oat bran products.

SETTINGS

Functional Foods Forum and the Department of Food Chemistry, University of Turku, and the Department of Food Technology, University of Helsinki.

SUBJECTS

One male and nine female volunteers were recruited from university students and staff, and all completed the study.

INTERVENTIONS

GI and II of different products were calculated for each subject using the average of parallel glucose tolerance tests and the subsequent glycemic/insulinemic responses for each product. Average indexes for products were calculated according to the individual data.

RESULTS

The glycemic responses to oat products with increasing amounts of beta-glucan had lower peak values than the reference glucose load. The amount of extractable beta-glucan had a high correlation between the glycemic and insulinemic response.

CONCLUSION

In addition to the total amount of beta-glucan in oat products, the amount of extractable beta-glucan in oat products explains the magnitude of the decrease in glycemic responses to carbohydrate products.