Application of vibrational and fluorescence spectroscopy to the compositional analysis of colored-flesh potatoes.

Background: Determination of composition and physicochemical parameters of natural products requires dedicated, often laborious and expensive, analytical protocols. Different spectroscopic techniques, in conjunction with chemometrics, seem to have a considerable potential in direct analysis of raw plant material and foods, without any chemical treatment.

Results: Fluorescence spectroscopy and three vibrational spectroscopy techniques were applied to determine total polyphenol content, antioxidant activity and macronutrient levels in red- and purple-fleshed potato varieties.

Physicochemical parameters, sensory profile and concentration of volatile compounds and anthocyanins in beers brewed using potato variety with purple flesh.

In the recent years, beer brewers are experimenting with using various substrates, other than traditional barley malt, water, hops, and yeast for beer production, because new adjuncts to the beer brewing can add new sensory and functional properties to this beverage. Novel potatoes with purple or red-colour flesh are a good and cheap starch source and are rich in bioactive components, which could increase the nutritive value of the produced beer. The aim of the study was to determine whether some part of barley malt can be replaced by the potatoes of purple-colour flesh and assessment of properties of such beer.

Content and Stability of Hydroxycinnamic Acids during the Production of French Fries Obtained from Potatoes of Varieties with Light-Yellow, Red and Purple Flesh.

Potatoes with different flesh colours contain health-promoting compounds, i.e., hydroxycinnamic acids, which vary in content and stability during thermal processing.

The Functional and Physicochemical Properties of Rice Protein Concentrate Subjected to Acetylation.

The aim of the present study was to increase the value of rice protein concentrate (RPC) by improving the functional properties of a preparation subjected to acetylation and analyze the impact of this chemical modification on chemical composition, digestibility, and protein patterning using SDS-PAGE electrophoresis and FT-IR spectroscopy. In the modified samples, the protein content increased (80.90-83.

Microbiological and Physicochemical Composition of Various Types of Homemade Kombucha Beverages Using Alternative Kinds of Sugars.

Kombucha is a beverage made by fermenting sweetened tea with a symbiotic culture of yeast and bacteria. Literature data indicate that the kombucha beverage shows many health-promoting properties such as detoxification, chemo-preventive, antioxidant, antimicrobial, antifungal, and general strengthening. The research conducted focuses on the analysis of polyphenolic compounds formed in the fermentation process using ultra-efficient liquid chromatography, as well as on checking the antimicrobial properties of kombucha against pathogenic bacteria and yeasts found in food.

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.

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

An application of solid C 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 C 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.

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.

Characterization of Bioactive Compounds of (L.) Mill. Seeds from Spanish Cultivars.

(L.) Mill. is the Cactaceae plant with the greatest economic relevance in the world.

Study of Antioxidant Activity of some Medicinal Plants Having High Content of Caffeic Acid Derivatives.

Recently, there has been increasing interest in medicinal plants, due to their content of health-promoting compounds, e.g., caffeic acids derivatives.

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 effect of frying on glycidyl esters content in palm oil.

The changes in palm oil, as affected by frying temperature, and content of the glycidyl esters (GEs) were studied. Potato chips were fried intermittently in palm oil, which was heated for 8 h daily over five consecutive days. Frying was conducted at three frying temperatures: 150, 165 and 180 °C.

The effect of pan frying on thermooxidative stability of refined rapeseed oil and professional blend.

The pan fryings of frozen pre-fried French fries in refined rapeseed oil (RO) and professional blend (PB) were of 8 h duration. Initially, while fresh, and after every 1 h of frying, the oils were analyzed for acid and anisidine values, colour, refractive index, fatty acid composition (by GC), polar fraction content and composition (by high pressure size exclusion chromatography). Additionally the fat content and fatty acid composition of French fries were determined.

Monitoring of glycidyl fatty acid esters in refined vegetable oils from retail outlets by LC-MS.

Background: Glycidyl fatty acid esters (GEs) are a newly identified class of food process contaminants. The main source of these compounds is refined oils. Because of the potential release of free glycidol, it is necessary to enable a more accurate exposure assessment.

The Effect of Type of Oil and Degree of Degradation on Glycidyl Esters Content During the Frying of French Fries.

The aim of the study was to determine the effect of oil degradation on the content of glycidyl esters (GEs) in oils used for the frying of French fries. As frying media, refined oils such as rapeseed, palm, palm olein and blend were used. French fries were fried for 40 h in oils heated to 180 °C in 30-min cycles.

The effect of raw materials on thermo-oxidative stability and glycidyl ester content of palm oil during frying.

Background: The objective of this research was to determine the effects of the water content of food incorporated into frying oil on oil degradation and the content of glycidyl esters. Potato chips, French fries and snacks were fried intermittently in palm oil, which was heated at 180 °C for 8 h per day over five consecutive days. Thermo-oxidative and physical alterations, changes in fatty acid composition, total polar components, polar fraction composition, and water content were analysed.

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.

Biomass production by novel strains of Yarrowia lipolytica using raw glycerol, derived from biodiesel production.

This study demonstrated the potential applicability of the isolated strains of Yarrowia lipolytica for the valorization of glycerol waste generated during biodiesel production, throughout biomass production. Twenty-one strains were isolated from different environments and identified as Y. lipolytica.

Characteristics of antioxidant activity and composition of pumpkin seed oils in 12 cultivars.

The objective of this study was to determine the antioxidant properties, and provide characteristics, of the oil obtained from the seeds of 12 pumpkin varieties belonging to the species Cucurbita maxima Duch. and Cucurbita pepo L. Another objective was to establish which of the two extracting agents, ethanol or methanol, is more effective.

Screening of acrylamide contents in potato crisps using process variable settings and near-infrared spectroscopy.

In order to study the formation of acrylamide in potato crisps during processing, an experimental design was set up. The design variables were drying time (6 levels), frying temperature (2 levels) and frying time (8 levels). The design contained 36 samples, which were analysed for acrylamide contents using LC high-resolution mass spectroscopy (LC-HRMS), and fat contents using the Soxhlet apparatus.

Addition of glycine reduces the content of acrylamide in cereal and potato products.

The effects of adding amino acids on the content of acrylamide in potato crisps, French fries, flat breads, and bread crusts were investigated. Addition of glycine or glutamine during blanching of crisps reduced the amount of acrylamide by approximately 30% compared to no addition. No effect was found in French fries.

Effective ways of decreasing acrylamide content in potato crisps during processing.

The aim of this work was to examine the effect of blanching or soaking in different acid solutions on the acrylamide content in potato crisps. Furthermore, the effects of a shorter frying time and a lower frying temperature combined with a postdrying were investigated. Soaking or blanching of potato slices in acidic solutions decreased the pH of potato juice and increased the extraction of amino acids and sugars.