Quality and nutritional value of cookies enriched with plant-based protein preparations.

BACKGROUND: The objective of the study was to determine the effect of addition of plant-based protein preparations in cookie recipes on the quality and nutritional value of the obtained products. Wheat flour was replaced by 10%, 20% or 30% of pea, hemp seed, pumpkin and sunflower seed preparations. Baked cookies were analysed for chemical composition, amino acid profile, colour and texture as well as organoleptic attributes and overall acceptability. RESULTS: The addition of plant protein preparations improved the nutritional value of cookies by supplementing them with threonine and part of lysine. Replacing at least 20% of wheat flour with pea protein allowed the production of cookies with a well-balanced amino acid profile. The use of pea and sunflower proteins improved the appearance of the obtained products (consumer notes from 7.4 to 8.0) in comparison to the control sample (note 7.2). The physical properties of cookies were changed while organoleptic properties worsened. Cookies with the most desirable sensory values were obtained using the pea protein preparation. Acceptable cookies were also obtained with pumpkin and sunflower seed protein preparations, if the proportion of additive did not exceed 20% in relation to the amount of wheat flour. CONCLUSION: The use of protein preparations from pumpkin and sunflower as well as from hemp seeds allows the production of cookies with acceptable sensory characteristics that could diversify the range of cookie products. In the case of oilseed preparations, the amount of additive is limited primarily by the colour and taste of the finished products. © 2022 Society of Chemical Industry.

Modeling of Antioxidant Activity, Polyphenols and Macronutrients Content of Bee Pollen Applying Solid-State 13C NMR Spectra.

An application of solid 13C nuclear magnetic resonance (NMR) spectroscopy for the determination of macronutrients, total polyphenols content, antioxidant activity, N C S elements, and pH in commercially available bee pollens is reported herein. Solid-state 13C NMR spectra were recorded for homogenized pollen granules without chemical treatment or dissolution of samples. By combining spectral data with the results of reference analyses, partial least squares models were constructed and validated separately for each of the studied parameters. To characterize and compare the models' quality, the relative standard errors of prediction (RSEP) were calculated for calibration and validation sets. In the case of the analysis of protein, fat and reducing sugars, these errors were in the 1.8-2.5% range. Modeling the elemental composition of bee pollen on the basis of 13C NMR spectra resulted in RSEPcal/RSEPval values of 0.3/0.6% for the sum of NHCS elements, 0.3/0.4% for C, 1.8/1.9% for N, and 4.2/6.1% for S quantification. Analyses of total phenolics and ABTS antioxidant activity resulted in RSEP values in the 2.7-3.5% and 2.8-3.8% ranges, respectively, whereas they were 1.4-2.1% for pH. The obtained results demonstrate the usefulness of 13C solid-state NMR spectroscopy for direct determination of various important physiochemical parameters of bee pollen.

Comparative evaluation of the antioxidant, antimicrobial and nutritive properties of gluten-free flours.

Gluten-free flours are interesting alternative to wheat flours. They could be by-products of oilseed processing, characterized by high content of bioactive compounds. Therefore the aim of the study was to determine the antioxidant, antimicrobial properties, amino acid and fatty acid profile of flours obtained as by-products from the oil industry. The highest total polyphenol content and antioxidant activity was found to have evening primrose flour. The widest spectrum of microbial growth inhibition was indicated for corn germ extract which showed no antimicrobial activity only against Bacillus subtilis. The highest protein content was found in pumpkin, peanut and almond flours (more than 50 g/100 g). The major abundant amino acids in all the analysed oilseed cake flours were aspartic acid, glutamic acid and arginine. The analysed gluten-free flours were found to be a good source of polyunsaturated fatty acids (PUFAs), which comprised mainly linoleic acid and α-linolenic acid, whereas the best source of PUFAs was evening primrose flour. The results suggest that the cold-pressed seed flours possess valuable chemical composition and may be considered for improvement of the nutritional properties of food products.

Effect of Acetylation on Physicochemical and Functional Properties of Commercial Pumpkin Protein Concentrate.

The purpose of the present study was to determine the effects of acetylation with different doses of acetic anhydride on the chemical composition and chosen functional properties of commercial pumpkin protein concentrate (PPC). The total protein content decreased as compared to unmodified samples. Electrophoretic analysis revealed that in the acetylated pumpkin protein, the content of the heaviest protein (35 kDa) decreased in line with increasing concentrations of modifying reagent. Acetylation of PPC caused a significant increase in water-binding and oil-absorption capacity and for emulsifying properties even at the dose of 0.4 mL/g. Additionally, an increase in foaming capacity was demonstrated for preparations obtained with 2.0 mL/g of acetic anhydride, whereas acetylation with 0.4 and 1.0 mL/g caused a decrease in protein solubility as compared to native PPC.

The Free-Amino-Acid Content in Six Potatoes Cultivars through Storage.

Potatoes of six cultivars (Solanum tuberosum L.) with red, purple, and yellow flesh were stored at 2 and 5 °C for 3 and 6 months, and the influence of these factors on the content of free amino acids was determined. The potato cultivar and storage time had the greatest impact on the free amino acid content. The tubers of red-fleshed (Rote Emma) and purple-fleshed (Blue Congo) potatoes contained over 28 mg/g DM of free amino acids, and the Blaue Annelise cultivar with purple flesh had over 18 mg/g DM. After 6 months, the highest increase in their content (by 36%) was recorded in tubers of the Fresco cultivar (yellow-fleshed). In the analysed potatoes, the content of alanine, proline, serine, γ-aminobutyric acid, and α-aminoadipic acid increased, while that of asparagine, aspartic acid, and glutamine decreased. Asparagine decreased to the greatest extent in "Blaue Annelise" potatoes (by 24%) and that of glutamine in tubers of Rote Emma and Vineta by 18%.

Determination of nutritional parameters of bee pollen by Raman and infrared spectroscopy.

Vibrational spectroscopy was applied to determine macronutrient levels, total polyphenols (TPs) content, antioxidant activity, pH and color parameters in bee pollens. Raman, attenuated total reflection and diffuse reflectance spectra in the mid- and near-infrared regions were recorded for the homogenized pollen granules. Combining spectral data and the results of reference analyses, partial least squares (PLS) models were constructed and validated. The relative standard errors of prediction (RSEP) were calculated for the calibration and validation sets. Regarding macronutrient analysis, the latter were found to be in the 1.7-2.3%, 2.5-3.6% and 2.6-3.3% ranges for protein, reducing sugars and fat determination, respectively. These errors amounted to 3.1-3.5% for TPs and 2.2-3.4% for antioxidant activity quantification, respectively, whereas they were found to be in the 1.5-2.3% and 1.6-3.2% ranges for pH and the color parameters' determination.

Trypsin inhibitor, antioxidant and antimicrobial activities as well as chemical composition of potato sprouts originating from yellow- and colored-fleshed varieties.

Potato sprouts could be a valuable resource of phytochemicals such as secondary plant metabolites, potential antioxidants and nutritive compounds. In this work, potato sprout extracts of five varieties were examined; they differed in major glycoalkaloid content, trypsin inhibitor activity, total polyphenol content and antioxidant activity, as well as in antimicrobial activity against Gram + and G - bacteria, and yeast. Sprouts of colored-fleshed tubers were characterized by higher trypsin inhibitor activity than sprouts of yellow potatoes. The strongest microorganism growth inhibition effect was observed for macerate with sprouts from the purple-fleshed Blaue Annelise variety against B. subtilis, whereas C. albicans yeasts were sensitive to macerates with sprouts from purple-fleshed Blue Congo and yellow-fleshed Vineta potato varieties.

Amino acid composition of flesh-coloured potatoes as affected by storage conditions.

The study determined nitrogen compounds and amino acid profile in dry matter of potatoes differing in flesh colour, stored at 2 °C and 5 °C for three and six months. With increased storage time, the total protein content and particularly amino acid content declined. The coagulable protein content increased at three months' storage by 25%. The majority of the amino acid content decreased from 19 to 6% and from 38 to 21% after three and six months' storage, respectively. Storage temperature did not influence the coagulable protein content or serine, glycine, cysteine, tyrosine and phenylalanine. However, potatoes stored at 2 °C contained slightly more amino acids than tubers stored at 5 °C. Independently of the storage conditions, potatoes of yellow-fleshed Fresco and red-fleshed Herbie 26 varieties were characterised by a relatively high nutritive value, limited by leucine (CS = 84), methionine plus cysteine (CS = 78) and leucine (CS = 72), respectively.

Anthocyanin and antioxidant activity of snacks with coloured potato.

Coloured-fleshed potatoes of four varieties were used as raw material for coloured flour and fried snack production. The effects of thermal processes traditionally used in dried potato processing and in snack pellet manufacturing on anthocyanin profiles, total polyphenols and antioxidant properties of obtained half- and ready products were studied. There was a significant influence of potato variety on the experimental flour and snack properties. Flours with the highest antioxidant activities were obtained from Salad Blue and Herbie 26 potatoes; however, the flour prepared from the Blue Congo exhibited a much higher total polyphenol and anthocyanin content. Snacks produced with coloured flour had 2-3 times higher antioxidant activities, 40% higher contents of polyphenols, attractive colour and better expansion compared to control samples. The lowest losses of anthocyanins during snack processing were in snacks with flour from the purple-fleshed Blue Congo and red-fleshed Herbie 26.