Oxidative stability of whole wheat bread during storage

Changes in Lipid Metabolites and Enzyme Activities of Wheat Flour during Maturation

The maturation of wheat flour is a transformative process that elevates its processing and culinary attributes to their peak performance levels. Despite extensive research on starch and gluten protein modifications, the impact of lipid changes has been largely unexplored. This study addresses this gap by examining the maturation of freshly milled wheat flour at 15 °C, 25 °C, and 40 °C over 60 days, focusing on enzymatic activities-lipase, lipoxidase, and catalase-and lipid metabolites, including free fatty acids, conjugated trienes, p-anisidine value, and total oxidation value. The results of this study showed that free fatty acids continued to increase at all temperatures, with the most significant increase of 50% at 15 °C. The p-anisidine value followed a pattern of initial increase followed by a decline, while conjugated trienes were markedly higher at 40 °C, suggesting temperature's significant influence on lipid peroxidation. Notably, total oxidation values became erratic post 30 days, indicating a shift in oxidative dynamics. This study underscores the correlation between lipid metabolites and enzymatic activities, revealing the enzymes' pivotal role in lipid oxidation. The interplay of temperature and time offers valuable insights for optimizing wheat flour maturation, ensuring superior quality for various applications.

Effect of tea polyphenols as an antioxidant on pork for frying at different temperatures and times

The aim of this study was to investigate the effect of frying on the antioxidant properties of tea phenols added to pork. The antioxidant capacity of tea polyphenols with different concentrations was tested using different assays including total antioxidant capacity (T-AOC) (FRAP method), thiobarbituric acid reactive substance, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging, and 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) radical scavenging. Our results indicated that tea polyphenols have a great antioxidant capacity and that a high frying temperature causes fat oxidation. Our study confirmed that DPPH assay is more suited to lipophilic compounds or compounds with high lipid content. In a frying temperature of 180°C, the DPPH-free radical scavenging ability of pork was not decreased. Further experiments remain necessary to explore specific temperatures with the same results. This study provides new process parameters and new references for processing techniques of healthy and high-quality pork products.

Approach to evaluate the sensory quality deterioration of chicken seasoning using characteristic oxidation indicators

Sensory quality deterioration of chicken seasoning was investigated using physicochemical properties, gas chromatography-mass spectrometry (GC-MS) and descriptive sensory analysis to approach an evaluation of the chicken seasoning deterioration. It was found that both peroxide value (POV) and total oxidation value (TOTOX) increased with the chicken seasoning deterioration, suggesting a dominant of the lipid oxidation in the sensory quality deterioration of chicken seasoning. Moreover, a continuously decreasing linoleic acid and contradictory increasing in volatile aldehydes (specifically for hexanal) indicated as characteristic oxidation indicators to evaluate the sensory quality deterioration. PLSR results further elucidated that the evolution of aldehydes was highly correlated with sensory quality deterioration. These results suggest the POV, TOTOX and hexanal as valuable indicators and provide a novel approach to quality and rapidly evaluate the sensory quality deterioration of chicken seasoning.

Cereal and Confectionary Packaging: Background, Application and Shelf-Life Extension

In both public and private sectors, one can notice a strong interest in the topic of sustainable food and packaging. For a long time, the spotlight for optimization was placed on well-known examples of high environmental impacts, whether regarding indirect resource use (e.g., meat, dairy) or problems in waste management. Staple and hedonistic foods such as cereals and confectionary have gained less attention. However, these products and their packaging solutions are likewise of worldwide ecologic and economic relevance, accounting for high resource input, production amounts, as well as food losses and waste. This review provides a profound elaboration of the status quo in cereal and confectionary packaging, essential for practitioners to improve sustainability in the sector. Here, we present packaging functions and properties along with related product characteristics and decay mechanisms in the subcategories of cereals and cereal products, confectionary and bakery wares alongside ready-to-eat savories and snacks. Moreover, we offer an overview to formerly and recently used packaging concepts as well as established and modern shelf-life extending technologies, expanding upon our knowledge to thoroughly understand the packaging's purpose; we conclude that a comparison of the environmental burden share between product and packaging is necessary to properly derive the need for action(s), such as packaging redesign.

Characterization of Key Odorants in Scallion Pancake and Investigation on Their Changes during Storage

To characterize key odorants in scallion pancake (SP), volatiles were extracted by solvent extraction-solvent assisted flavor evaporation. A total of 51 odor-active compounds were identified by gas chromatography-olfactometry (GC-O) and chromatography–mass spectrometry (GC-MS). (Z/E)-3,6-Diethyl-1,2,4,5-tetrathiane was detected for the first time in scallion food. Application of aroma extract dilution analysis to extracts showed maltol, methyl propyl disulfide, dipropyl disulfide and 2-pentylfuran had the highest flavor dilution (FD) factor of 4096. Twenty-three odorants with FD factors ≥ 8 were quantitated, and their odor active values (OAVs) were calculated. Ten compounds with OAVs ≥ 1 were determined as the key odorants; a recombinate model prepared from the key odorants, including (E,E)-2,4-decadienal, dimethyl trisulfide, methyl propyl disulfide, hexanal, dipropyl trisulfide, maltol, acetoin, 2-methylnaphthalene, 2-pentylfuran and 2(5H)-furanone, successfully simulated the overall aroma profile of SP. The changes in odorants during storage were investigated further. With increasing concentrations and OAVs during storage, hexanal became an off-flavor compound.

Effect of superheated steam treatment on the lipid stability of whole wheat flour

This study aimed to investigate the effect of superheated steam treatment (SST) on lipid stability of whole wheat flour (WWF) during storage. After SST, the lipase and peroxidase of WWF were inactivated, and lipoxygenase activity was lower than 5% of its initial value. The total tocopherols decreased slightly in all SST groups, especially it only decreased by 1.1% at 190 °C for 5 s. Furthermore, the increase of fatty acid value in the control group was over 100-fold than that of the SST groups during storage. The unsaturated fatty acids and total tocopherols in WWF decreased gradually, but the decrease was alleviated by SST at 190 °C for 5 s. After storage, the relative content of hexanal and 2-pentylfuran in the SST groups were 4 and 0.3-fold than those in the control group, respectively. Thus, SST may be a potential approach to stabilise the quality of WWF.

Towards an ideotype for food-fuel dual-purpose wheat in Argentina with focus on biogas production

BACKGROUND

Wheat straw, one of the most abundant agricultural residues worldwide, can be used to produce biogas, which is considered one of the most efficiently produced renewable energies. Wheat grown with the dual-purpose of producing food and biogas should display simultaneously high grain and straw yields, low lodging susceptibility and high conversion efficiency of straw into biogas. The aims of this study were to determine the best food-fuel dual-purpose wheat candidates among 36 wheat genotypes-including French, CIMMYT and local (Criollo) germplasm-used in breeding programs in Argentina and to gain some insights into the relationships between key traits relevant for dual-purpose wheat genotypes.

RESULTS

High variability in individual key traits for dual-purpose wheat ideotype has been found. Genotypes of French origin displayed the highest grain yield, and those of CIMMYT origin, the lowest straw yield. Genotypes of Criollo origin showed the highest lodging susceptibility, and French ones, the lowest. Straw yield was positively correlated with grain yield in all genotypes, and negatively correlated with plant height in genotypes of Criollo origin. Straw conversion into biogas was measured in terms of the biogas potential production and kinetic parameters B_max (maximum specific biogas production) and k (first-order kinetic constant) were analyzed. All key traits were analyzed together by a principal component analysis. Baguette 31 and SNR Nogal, two genotypes of French origin, showed high grain yield, high-to-very high straw yield, low lodging susceptibility, and moderate-to-high B_max and k. Buck Guapo and Buck Baqueano, two genotypes of Criollo origin, displayed good values for grain yield, straw yield and B_max and k. However, their high lodging susceptibility precludes their production in shallow soils or high-input systems. Lastly, some old genotypes (e.g. Klein Atlas) harbored a good combination of all key traits and could prove valuable to be included in future breeding programs for dual-purpose wheat.

CONCLUSIONS

While none of the genotypes excelled in every key trait, a few candidates showed potential for dual-purpose ideotype, particularly Baguette 31 and SNR Nogal. The challenge lays in gathering all attributes for food and 2G fuel in the same genotype.

Improving wholegrain product quality by selecting lipid-stable wheat varieties

Lipid oxidation is one of the major quality issues of wholegrain wheat flour and products, despite their rich endogenous antioxidants. Diverse wheat germplasm resources are available for industrial production and breeding selection. Therefore, to improve the stability qualities of wholegrain, it is important to study lipid stability of wheat varieties, together with their endogenous antioxidant contents. In this study, 65 wheat varieties were evaluated for their oxidative stabilities under accelerated conditions. Primary and secondary oxidation products, radical scavenging activities, and tocol contents were analyzed to obtain a comprehensive understanding of lipid oxidation in wholegrain flour. The results showed significant diversity of lipid stability in the wheat varieties, with a 30-fold difference in hexanal content after 19 weeks of storage. Varieties, such as 'Velocity' and 'Arina', with high stability and high antioxidant contents, are potentially better suited for stable wholegrain products. The findings will benefit consumers with better quality wholegrain products.

Evaluation of the Content of Polyphenols, Antioxidant Activity and Physicochemical Properties of Tortillas Added with Bambara Groundnut Flour

The effect of substituting maize (masa) flour with Bambara groundnut flour in tortillas production was investigated. Thermal, antioxidant, physicochemical properties, degree of puffing and rollability of flour and tortillas were determined. Tortillas were produced from maize and Bambara Groundnut (BGN) flours at the ratio of 100:0, 95:5, 90:10, 85:15 and 80:20, respectively. Compositing maize with BGN flour showed an improvement on the proximate composition of maize flour and tortillas; however, carbohydrate content of tortillas significantly decreased with the addition of BGN in blends from 77.07 to 55.22. The temperatures of gelatinisation such as onset temperature (T_o) of flour blends increased from 57.50 to 71.95 °C, peak temperature (T_p) from 74.94 to 76.74 °C and the end temperature (T_e) from 81.72 to 91.58 °C. Composite flours and tortillas had higher values of polyphenolic compounds and antioxidant activities than the control sample. Textural properties of control tortillas were higher than that of composite tortillas. Increase in the levels of BGN flour improved the weight and thickness of tortillas. However, diameter and spread ratio decreased. Degree of puffing and rollability of tortillas increased with the incorporation levels of BGN flour.

Fortification of whole wheat flour with different iron compounds: effect on quality parameters and stability

The aim of this study was to evaluate the effects of fortification of whole wheat flour with different iron compounds, such as ferrous sulfate (FS), ferrous fumarate (FF), reduced iron (RI), ferric sodium ethylenediaminetetraacetate (NaFeEDTA), microencapsulated ferrous sulfate (FSm) and microencapsulated ferrous fumarate (FFm), on quality parameters: color, titratable acidity, peroxide value (PV) and hexanal values, during 120 days of storage. An iron content of 1.38 mg/100 g was quantified in non-fortified whole wheat flour and after fortification, the iron levels ranged from 4.80 to 6.29 mg/100 g. The fortification of whole wheat flour with different iron compounds showed changes on the quality parameters evaluated during storage with exception of the color. The whole flour acidity was affected mainly by NaFeEDTA. Compounds FS and FFm presented the highest PV in whole flour after 30 days of storage. Whole flours fortified with FS and FSm presented higher hexanal levels after 30 and 90 days of storage, respectively. Whole flours fortified with RI and NaFeEDTA presented more stability on quality parameters evaluated during storage period. Therefore, the different iron compounds, when used on whole wheat flour fortification, affect differently the quality of the product during storage.

An investigation of process contaminants’ formation during the deep frying of breadcrumbs using a bread coat model

The formation of acrylamide, hydroxymethylfurfural (HMF) and furfural was investigated in a deep fried breadcrumb coat model resembling the coat batter of breaded foods.

Short-term storage evaluation of quality and antioxidant capacity in chestnut-wheat bread

BACKGROUND

Bread traditionally made from wheat is now often supplemented with alternative functional ingredients as chestnut flours; no data have been previously published about the staling of chestnut-containing bread. Thus short-term storage (3 days) for chestnut flour-supplemented soft wheat bread is evaluated by means of selected physicochemical properties (i.e. water dynamics, texture, colour, crumb grain characteristic, total antioxidant capacity).

RESULTS

Bread prepared with a 20:80 ratio of chestnut:soft wheat flours maintained its moisture content in both crust and crumb. Crumb hardness, after baking, was found to be significantly higher than that of the soft wheat bread; it did not change during storage, whereas it significantly increased in the control bread until the end of the shelf life. The supplemented bread presented a heterogeneous crumb structure, with a significant decrease in the largest pores during shelf life, relative to the shrinkage of crumb grain. The control exhibited a significant redistribution of crumb holes, with a decrease in the smallest grain classes and an increase in the intermediate ones, most likely caused by cell wall thickening. The colour of the crumb remained unaltered in both breads. The crust of the control presented a significant decrease of a* (redness) and that of the supplemented bread exhibited a decrease of b* (yellowness). The antioxidant capacity was detected after day 1 of storage in the chestnut flour bread only.

CONCLUSION

Chestnut flour supplementation could represent a feasible way of producing bread with improved characteristics, not only just after baking but also during shelf life.

Antioxidant capacity of hydrolyzed porcine tissues

The antioxidative capacity of seven different porcine tissue hydrolysates (colon, appendix, rectum, pancreas, heart, liver, and lung) were tested by four different assays, including iron chelation, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) radical scavenging, and inhibition of lipid oxidation. All hydrolyzed tissues displayed antioxidant capacity in all four assays, with colon, liver, and appendix as the three most potent inhibitors of lipid oxidation (47, 29, and 27 mmol/L trolox equivalent antioxidant capacity [TEAC], respectively) and liver, colon, pancreas, and appendix as the four most potent iron chelators (92% ± 1.1, 79.3% ± 3.2, 77.1% ± 1.8, and 77% ± 2.3, respectively). Furthermore, colon and appendix showed good radical scavenging capacities with ABTS scavenging of 86.4% ± 2.1 and 84.4% ± 2.9 and DPPH scavenging of 17.6% ± 0.3 and 17.1% ± 0.2, respectively. Our results provide new knowledge about the antioxidant capacity of a variety of animal by-products, which can be transformed into antioxidant hydrolysates, thereby creating added value.

Antioxidant capacity versus chemical safety of wheat bread enriched with pomegranate peel powder

Pomegranate peel powder (PP), a by-product of the pomegranate juice industry rich in polyphenols, was explored for use in bread production, due to its potential health effects. Wheat bread was prepared using different levels for replacement of flour with PP (0 to 10 g per 100 g flour) resulting in antioxidant levels expressed as Trolox equivalent antioxidant capacity values (TEAC) ranging from 1.8 to 6.8 μmol TEAC per g bread for fresh bread. TEAC remained constant during 5 days of storage in polyethylene bags at room temperature. The oxidative stability was evaluated by detection of radicals by direct electron spin resonance (ESR) spectroscopy, and peroxide value, and the highest capacity of scavenging of radicals (Fremy's salt) and the lowest content of peroxide values were found in bread with the highest percentage of PP. Safety evaluation was performed by the Artemia salina assay. An increased death rate of the brine shrimp larvae was found as a function of the replacement of wheat flour with PP in fortified bread providing a general screening method for the toxicological test of polyphenol fortified bread to be recommended for use in product development in addition to subjective evaluation. Based on both toxicological and subjective evaluations an addition of 2.5% PP is recommended for the actual product.

Changes in chemical composition and antioxidative properties of rye ginger cakes during their shelf-life

Changes in chemical composition and antioxidative properties of rye ginger cakes during their shelf-life were investigated in this study. In particular, the changes in antioxidants content, antioxidative and reducing capacity, and Maillard reaction development in rye ginger cakes after long-term storage were addressed. Ginger cakes produced according to the traditional and current recipe were stored for 5 years at room temperature in a dark place. The total phenolic compounds (TPC), inositol hexaphosphate (IP6), reduced (GSH) and oxidised glutathione (GSSG) contents, antioxidant and reducing capacity and Maillard reaction products (MRPs) were determined in ginger cakes after storage and then compared to those measured after baking. After long-term storage a decrease in TPC and IP6 contents in cakes was noted. In contrast, an increase in antioxidative and reducing capacity of stored cakes was observed. Long-term storage induced formation of furosine, advanced and final Maillard reaction products and caused changes in both reduced and oxidised forms of glutathione. After long-term storage the modest changes in furosine, FAST index and browning in ginger cake formulated with dark rye flour may suggest that this product is the healthiest among others. Therefore, traditional rye ginger cakes can be considered as an example of a healthy food that is also relatively stable during long term storage as noted by the small chemical changes observed in its composition.