Deep‐fat frying under moderate vacuum of potato cylinders

This study evaluates parameters relating to the mass transfer during the frying of potato cylinders at different temperatures (100, 120 and 140 °C) and moderate vacuum (around 25 kPa). In all cases, there is a linear relation between water loss and fat uptake. The parameters relating to the textural and structural modifications show less marked changes in vacuum fried products compared to those fried under atmospheric pressure. The maximum penetration force reaches 30%–40% of the initial hardness in vacuum frying and 10% for atmospheric pressure frying; starch gelatinization and pectin methylesterase enzyme activity reduce more quickly under atmospheric pressure, although after 240 s both values are negligible. The scanning electron microscopy images verify that the surface of potato cylinders fried under vacuum or atmospheric pressure are completely different as a result of the steam being released at different temperatures.     

Consumer Input for Developing Human Food Products Made with Sorghum Grain

Abstract: Because sorghum grain has important characteristics (for example, great antioxidant profile) for introduction into the regular human diet, producers and industry aim to develop successful products using sorghum as the base. The 1st step in developing products attractive for consumers is understanding consumer needs and expectations. Conjoint analysis determines attributes which may be important or unimportant for one product. In this study, focus groups and conjoint analysis were used to establish which attributes are helpful for promoting purchase intent of sorghum grain products. Once those characteristics were chosen, a national survey was conducted to confirm the selection. During the focus groups, the heath aspects of grain products seemed to be the most appealing for consumers, whereas conjoint analysis showed that sensory attributes were the principal drivers for purchase intent. Practical Application: The data presented in this study are essential for industry as a starting point for developing sorghum grain based food products. It is necessary to address consumers’ demands to ensure new products’ success in the market, and the present study clearly shows this consumers’ input.     

The Effect of Food Type (Fish Nuggets or French Fries) on Oil Blend Degradation during Repeated Frying

Abstract: Oil that is reused multiple times for deep frying goes through changes in chemical composition and physical characteristics, affecting the quality of the fried foods. In this study, the effect of the food type (fish nuggets or French fries) on the degradation of an oil blend during the deep‐fat frying of each food at 180°C during 12 days was determined, and the characteristics of the fried products were evaluated. The degradation of oil during repeated use was relatively faster when fish nuggets were fried than when French fries were fried, as higher values of total polar compounds were obtained. Practical Application: The results are useful for producers of French fries and fish nuggets, such as restaurants or fast foods sellers, providing them with practical guidelines within the permitted values established by the regulatory authorities. The studied foods have high economic importance and are different in their composition. Under the studied conditions, the tested oil blend may be used during 4 d (4 h per day) with a daily replenishment, without discarding the oil when frying fish nuggets, and must be discarded after 8 d when French fries are processed. This suggestion allows preparing safe fried foods for consumers.     

Compositional characteristics,texture, shelf-life and sensory quality of snack crackers produced from non-traditional ingredients

The study was conducted to evaluate the effect of non-traditional and highly available and nutrient-dense ingredients in the production of value-added crackers. The crackers were prepared by combining partially defatted chia flour, wheat germ, quinoa, and oat. The antioxidant activity and the polyphenol content were 7.0–8.4 times higher in crackers produced with non-traditional ingredients compared to the control snack. The hydroperoxide value indicated a low oxidative deterioration of the oil. The sample with 10% of partially defatted chia flour was selected for shelf-life test under storage conditions and sensory evaluation. Modified atmosphere exerted a protective effect on the lipid stability regardless of the incorporation of BHT to the formulation. All the evaluated attributes scored highly during consumer acceptance. The formulated cracker presented a relevant content of protein, dietary fibre and omega-3 and -6 fatty acids. Based on these results, the crackers containing non-traditional ingredients resulted in a product with a good potential for both consumer acceptance and outstanding nutritional benefits.     

Gluten-free cakes with walnut flour: a technological,sensory, and microstructural approach

Walnut flour (WF), a by-product of walnut oil production, is characterised by high polyunsaturated fatty acids, proteins, and fibre contents and presents suitability for bakery products. However, when using non-traditional ingredients, it is essential to evaluate the effect on the quality properties of the final product. So, this work aimed to assess the impact of WF on the technological, physicochemical, and sensory properties of gluten-free (GF) cakes. WF was added at a flour blend (cassava (CS) and maize (MS) starches and rice flour) at 0, 10%, 15%, and 20%. The results showed that WF modified starch gelatinisation, increased amylose–lipid complex (ALC) content, and made crumbs easier to chew. Besides, the total dietary fibre (TDF) and protein content significantly increased. Cakes with 15% WF presented the highest specific volume (SV) and no differences in overall acceptability with respect to control. Hence, WF is a suitable ingredient for gluten-free bakery products.     

Geographical Authentication of Tequila According to its Mineral Content by Means of Support Vector Machines

The elemental profile of tequila samples from the three main production areas of the State of Jalisco, namely Amatitlan, Guadalajara, and Tequila, was used to carry out their geographical characterization. With this aim, the concentration of Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, S, Sr, and Zn was determined by inductively coupled plasma atomic emission spectroscopy. Principal component analysis was addressed to visualize data trends. The number of input variables was reduced by means of backward stepwise linear discriminant analysis and support vector machines were used to construct an adequate classification model. The best classification performance was obtained by a linear support vector machine model with 100% of prediction ability.     

Pro-oxidative effects of melanoidin–copper complexes on isolated and cellular DNA

High molecular weight Maillard reaction products (melanoidins) are described to possess metal-chelating properties. Whereas in food systems, this ability contributes to antioxidant properties, the consequences on biological systems are not quite clear. The study was aimed to evaluate the implication of metal complexation by melanoidins on DNA damage. Melanoidins prepared with d-glucose and different l-amino acids under water-free reaction conditions were charged with cupric ions. The effect on isolated DNA was investigated by the PM2 assay and on cellular systems in the human colon carcinoma cell line HCT-116 by alkaline unwinding. Independent of the amino acid composition, pure melanoidins (MW >14 kDa) did not cause significant DNA damage. By charging melanoidins with Cu²⁺ ions, a considerable DNA strand breaking activity was detectable, which was again amplified in an oxidative milieu (addition of hydrogen peroxide). Since Cu²⁺ normally does not provoke the formation of reactive oxygen species (ROS) via Fenton-type reaction, the results obtained have to be attributed to reducing properties of melanoidins. Thus, in melanoidin–copper complexes redox cycling may take place leading to Cu⁺ which subsequently undergoes Fenton-type and Haber–Weiss reactions. As a consequence, ROS are formed, which may explain the generation of DNA strand breaks.     

Validation by a Collaborative Interlaboratory Study of an ELISA Method for the Detection of Caseinate Used as a Fining Agent in Wine

The clarification or fining of wine removes undesirable substances such as proteins, phenols, and tannin compounds that would cloud the wine and cause bitterness and astringency. Caseinates have useful fining properties, but their residues could present a risk for allergic subjects. A commercial kit that was developed to detect caseinates in food has been examined for its applicability to a wine matrix; it is sensitive to caseinates at concentrations as low as 1 ppm. The general characteristics of the caseinate assay, described below in detail, are as follows. It is a sandwich enzyme-linked immunosorbent assay (ELISA): the microplate is first coated with a specific anti-casein antibody; and after incubation with the wine sample, a secondary anti-casein antibody conjugated with horseradish peroxidase is added to form a sandwich. The antibodies have been tested for their immunoreactivity and the reproducibility of antigen recognition has been measured. An interlaboratory collaborative trial was organized to evaluate the performance of this ELISA method and its ease of use by laboratories routinely dealing with wine/food analyses. The results satisfy the criteria established by the International Organisation of Vine and Wine in the Compendium of International Methods of Analysis MA-EAS1-07-ETCOL.     

Amaranth seed varieties. A chemometric approach

In this work, the amino acid and fatty acid profiles were determined in two advanced lines of amaranth seeds: Amaranthus hypochondriacus × Amaranthus cruentus AH17a and Amaranthus cruentus AcG6/17a; as well as in two new varieties: Amaranthus cruentus var. Candil and Amaranthus hypochondriacus var. Dorado. The following contents were found: protein (18.76–26.00 %), dietary fiber (15.91–17.80 %) and total lipids (10.62–11.44 %), high concentrations of unsaturated fatty acids (77.80–82 % of total lipids), linoleic acid (41.94–55.50 % of total lipids) and lysine (47.3–68.6 mg g^?1 of protein) were also found. Based on these composition data, chemometric tools were used to classify these new varieties and lines by unsupervised methods—principal component analysis and cluster analysis; as well as by supervised methods—sequential discriminant analysis (DA) and partial least squares DA. It was possible to correctly classify all varieties and lines using 11 variables. In conclusion, it was found that new varieties and advanced lines of amaranth show proper nutritional quality, which reveals the potential of this genus as agro-food. Also, a complete chemometric assessment allowed us to distinguish between these new varieties and lines.