Estimation of oxidative indices in the raw and roasted hazelnuts by accelerated shelf-life testing

NIR-HSI for the non-destructive monitoring of in-bag hazelnut oxidation

This study explores the application of Near-Infrared Hyperspectral Imaging (NIR-HSI) as a non-destructive method for monitoring the oxidation of hazelnuts (Corylus avellana) stored under different atmospheric conditions (air, nitrogen, and vacuum) and light exposures, directly inside plastic bags, without the need for packaging removal nor sample preparation. Hazelnuts were imaged over a 78-day storage period, and data were analysed using ANOVA-Simultaneous Component Analysis (ASCA) to quantify the effects of time, atmosphere, and light on oxidation. Individual hazelnuts within each bag were segmented for analysis to study inter-hazelnut variability. Images were studied individually to detect oxidation patterns on the surface. Results indicate that time is the primary driver of oxidation, as expected, with atmosphere and light significantly impacting oxidation rates. Vacuum storage was most effective at reducing oxidation, while light exposure under ambient conditions accelerated oxidation via photooxidation. Sensory analysis confirmed that spectroscopic indicators of oxidation corresponded to perceptible sensory changes, validating NIR-HSI as a reliable tool for assessing hazelnut quality. This study underscores the potential of NIR-HSI and chemometrics for quality control and shelf-life assessment in hazelnuts and other oxidation-prone food products.

Oxidative Stability of Cottonseed Butter Products under Accelerated Storage Conditions

Cottonseed is a natural product of cotton (Gossypium spp.) crops. This work evaluated the oxidative stability of cottonseed butters through accelerated autoxidation by storage at 60 °C for 25 days. Three oxidative stability parameter values (peroxide value, p-anisidine value, and total oxidation value) were monitored over the storage time. These chemical measurements revealed that the storage stability of the butter products was dominated by primary oxidation of lipid (oil) components, while the secondary oxidation levels were relatively unchanged over the storage time. An analysis of the tocopherols (natural oxidants in cottonseed) suggested not only the protection function of the molecules against oxidation of the cottonseed butter during storage, but also the dynamic mechanism against the primary oxidation of lipid components. Attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR) data confirmed no changes in the major C functional groups of cottonseed butters over the storage time. On the other hand, characteristic minor peaks of conjugated dienes and trienes related to lipid oxidation were impacted by the accelerated storage. As each day of accelerated oxidation at 60 °C is equivalent to 16 days of storage at 20 °C, observations in this work should have reflected the oxidative stability behaviors of the cottonseed butters after about 13 months of shelf storage under ambient storage conditions. Thus, these data that were collected under the accelerated oxidation testing would be useful not only to create a better understanding of the autooxidation mechanism of lipid molecules in cottonseed butters, but also in developing or recommending appropriate storage conditions for cottonseed end products to prevent them from quality degradation.

Shelf-Life Prediction and Thermodynamic Properties of No Added Sugar Chocolate Spread Fortified with Multiple Micronutrients

The development of fortified healthy pleasant foods, in which saturated fats are replaced with unsaturated ones, poses a challenge for the food industry due to their susceptibility to oxidative rancidity, which decreases product shelf-life, causes the destruction of health-promoting molecules, and forms potentially toxic compounds. A comparative study applying the Arrhenius model was carried out to investigate the oxidative stability and predict the shelf-life of a newly developed no added sugar chocolate spread formulated with sunflower oil, and fortified with vitamin D, Mg, and Ca checked against two commercially available spreads: No Palm and a well-known commercially available product (RB). The results obtained from the accelerated shelf-life testing for peroxide value (PV) showed relatively higher activation energy (Ea, 14.48 kJ/mol K) for RB, whereas lower Ea (11.31–12.78 kJ/mol K) was obtained for No Palm and all the experimental spread chocolates. Q10 values were comparable (1.202–1.154), indicating a similar catalytic effect of the temperature upon the oxidation rate across all the investigated samples. The positive Gibbs free energies ranged from 75.014 to 83.550 kJ/mol and pointed out that the lipid oxidation reaction in the chocolate spread was an endergonic process. The predicted shelf-life at 293.15 K was 8.57 months (RB), 7 months (No Palm), and 6.8 months for all the experimental spreadable chocolate. However, the higher production of hydroperoxides was observed in chocolate fortified with magnesium-calcium carbonate nanoparticles and stored at 313.15 and 323.15 K, suggesting these particles may enhance lipid oxidation.

Nutrient Content, Organoleptic Quality, and Shelf Life of Sagon Substitute From Lindur (Bruguiera gymnorrhiza L.) and Soybean Flour (Glycine max L.), as an Alternative Emergency Food

Lindur (Bruguiera gymnorrhiza L.) fruit as a mangrove species has not been widely developed. However, the combination of lindur fruit functional food with soybean flour has high carbohydrates and protein potential to serve as an additional food product in emergency conditions. Therefore, this study aims to evaluate the nutritional content, dietary fiber, organoleptic quality, and sagon shelf-life estimation of lindur and soybean flour, in accordance with emergency food quality requirements. The shelf life was determined using the Accelerated Shelf-life Testing (ASLT) method with the Arrhenius equation, where the sample was stored in an incubator at a temperature of 27, 37, as well as 47°C for 30 days, and the water content, peroxide number, and free fatty acid content were tested every 5 days. In addition, formulation P1 comprising 45% lindur flour and 35% soybean flour was discovered to be the best formulation, with a composition of 251.5 kcal/bar of energy, 6.3 g of fat, 4.4 g of protein, 30 g of carbohydrates, 15.79% dietary fiber, 1.84% ash content, and 4.03% water content. Therefore, the nutritional content of sagon substitution for lindur flour is in accordance with the emergency food quality requirements, except for the protein content. Also, the P2 sagon sample’s shelf life was estimated to be 37 days in polypropylene plastic packaging at a room temperature of 27°C.

Advances in cultivar choice, hazelnut orchard management, and nut storage to enhance product quality and safety: an overview

European hazelnut (Corylus avellana L.) is a major species of interest for nutritional use within the Betulaceae family and its nuts are widely used throughout the world in the chocolate, confectionery, and bakery industries. Recently its cultivation has been expanded in traditional producer countries and established in new places in the southern hemisphere, including Chile, South Africa, and Australia. Introducing hazelnut in new environments could reduce its productivity, lead the trees to experience eco-physiological disorders, and expose the crop to high pressure from common and new pests and diseases. Thus, new approaches in cultivar choice guidance, in the sustainable orchard management and even in nut storage and kernel quality evaluation are urgently required to improve the hazelnut production and processing chain. The main objective of this study was to systematize the published information regarding recent findings about the cultural operations that directly influence nut and kernel quality, support varietal choice for new plantations, and list the recent advances in nut storage and in quality and safety evaluation. © 2020 Society of Chemical Industry.