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Secondary growth is a common post-harvest problem when pre-infected crops are attacked by filamentous fungi during storage or processing. Several antifungal approaches are thus pursued based on chemical, physical, or bio-control treatments; however, many of these methods are inefficient, affect product quality, or cause severe side effects on the environment. A protein that can potentially overcome these limitations is the antifungal protein AFP, an abundantly secreted peptide of the filamentous fungus Aspergillus giganteus. This protein specifically and at low concentrations disturbs the integrity of fungal cell walls and plasma membranes but does not interfere with the viability of other pro- and eukaryotic systems. We thus studied in this work the applicability of AFP to efficiently prevent secondary growth of filamentous fungi on food stuff and chose, as a case study, the malting process where naturally infested raw barley is often to be used as starting material. Malting was performed under lab scale conditions as well as in a pilot plant, and AFP was applied at different steps during the process. AFP appeared to be very efficient against the main fungal contaminants, mainly belonging to the genus Fusarium. Fungal growth was completely blocked after the addition of AFP, a result that was not observed for traditional disinfectants such as ozone, hydrogen peroxide, and chlorine dioxide. We furthermore detected reduced levels of the mycotoxin deoxynivalenol after AFP treatment, further supporting the fungicidal activity of the protein. As AFP treatments did not compromise any properties and qualities of the final products malt and wort, we consider the protein as an excellent biological alternative to combat secondary growth of filamentous fungi on food stuff.

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Strawberry fruits have a very short shelf‐life owing to their high degree of perishability. This study aimed to determine the efficacy of chitosan (CH) incorporated with olive oil residues (OOR) coatings on overall quality of cold‐stored strawberry fruits compared to watery wax incorporated with thiabendazole. Strawberries were sprayed after infected with Rhizopus stolonifer with six different coating formulas and uncoated fruits. Indeed, all freshness and microbiological parameters were significantly increased in uncoated fruits compared to coated fruits. Amazingly, the coated strawberry using CH‐OOR 2% was reduced significantly the gradual decline in their contents of total phenolics, flavonoids and their antioxidants. Likewise, it was the lowest fruits in decayed area, fungal count and malondialdehyde development. Then, fruits were coated with CH‐OOR showed uniform coating distribution, since it was impossible to see any pores. Therefore, coating treatments with CH‐OOR was improved the membrane integrity and increased the keeping quality. Practical Applications Edible coatings could be an effective way for delaying the ripening process and extending the shelf‐life stability of strawberry during postharvest. The effectiveness of chitosan (CH)‐olive oil residue (OOR) as a novel edible coating, in comparison with watery wax‐thiabendazole was approved. The applicability of those films to maintain microbiological and freshness quality in strawberry during postharvest was succeed. Incorporation of OOR into CH increased its antifungal property against R. stolonifer in vivo and in vitro. Coating by CH‐OOR reduced phenolics, flavonoids and antioxidants decomposition in coated fruits compared to uncoated. CH‐OOR was able to slow down the gas exchange by reducing the CO2 of coated strawberry, which reduced their malondialdehyde development. Commercially, CH‐OOR could be explored as a novel and potential natural coating to substitute the synthetic agents in fruit packaging industries. The coating cost could increase the total cost about 6–8% where shelf‐life and keeping quality was improved.

The kinetics of heat inactivation and reactivation of peroxidase were examined in extracts of carrots, spinach and apricots. The enzyme from carrots was the most heatstable and showed the highest reactivation during storage whereas the peroxidase from apricots was the most heat-sensitive and showed no reactivation during storage. Higher rates of reactivation were generally observed for samples stored at -5'C compared to those stored at 4 and 18°C. The optimal pH for reactivation of peroxidase from spinach and apricots was pH 8.0. The presence of sodium chloride resulted in higher rates of reactivation during storage whereas sucrose had no significant effect.

Utilization of potato processing residues to produce a low caloric cupcake in present study was targeted. The functional properties of wheat flour (WF 72%) and dried potato peel varieties [Hermus (PPH) and Russet (PPR)] were carried out. Consequently, WF was partially substituted by both potato peels (PP) at 5% -20% to prepare mixtures for cupcake making. Approximate chemical composition and physical characteristics were determined. Rheological parameters of prepared formulas were assayed using Mixolab. Moreover, total phenolic compounds (TPC) and relative antioxidant activity (AOA) were evaluated. Quality parameters such as thiobarbituric acid (TBA), staling and microbiological attributes during storage were determined. In addition, a sensory evaluation of different substituted cupcake was performed as well. Results indicated that PPR had the highest water absorption capacity (WAC), oil absorption capacity (OAC) and swelling capacity (SC) followed by PPH then WF flours. Indeed, substituted WF with both PP at 5% and 10% didn't influence the thermo-mechanical properties including dough time development, stability, viscosity, gluten and starch characteristics drastically. Likewise, this substitution levels didn't affect the organoleptic properties which were confirmed by panelists, cupcake external and cross sections. Substituted WF by 5% -10% PP recorded sensory scores aftermost WF. Mildly, WF cupcake was higher in protein and fat contents than WF-PP cupcakes while lower in crude fiber. The WF-PP cupcakes at different substituted levels recorded lower energy value than WF cupcakes. Arguably, increasing both PP levels increased the TPC and AOA especially for WF-PPR cupcakes. Afterwards, WF-PPR 15% and 20% recorded the highest TPC and AOA contents to be 2.32 mg GAE g −1 dw and 3.44 µmol TE g −1 dw, respectively. No significant difference (p > 0.05) was found between WF-PP at 5% and WF cupcakes in physical and staling properties. WF-PPR cupcakes at different concentrations were lower TBA than WF cupcakes and mostly stable during storage period. It was revealed that substitution levels of 5% and 10% with PPH and PPR produced acceptable cupcakes which did not significantly differ from WF cupcakes.

Twelve low-calorie orange-based formulated jams were prepared mainly from orange, pumpkin and papaya, and then sweetened using fructose (F), stevioside (St) and sucralose (Su). The nutritional value of formulated jams was estimated after the approximate chemical composition and total soluble solid have been determined. The effect of storage on total phenolic compounds, antioxidant capacity, carotenoids content and vitamin C was investigated. Organoleptical attributes of prepared low-calorie jams were done as well. Results indicated that the nutritive value [kcal 100 g −1 fw] ranged from 88.10 ± 0.60 to 164.34 ± 0.41; total phenol content (TPC, mg GAE 100 g −1 fw] ranged from 188.52 ± 2.45 to 411.79 ± 3.3; the antioxidant capacity (μmol TE g −1 fw) ranged from 14.57 ± 0.86 to 32.39 ± 1.19; total carotenoids [mg 100 g −1 fw] ranged from 115.20 ± 5.66 to 204.33 ± 4.21; vitamin C [mg 100 g fw] ranged from 8.94 ± 1.07 to 28.77 ± 4.46; total soluble solids [Brix] ranged from 22.53 ± 0.05 to 43.37 ± 0.13. Jams storage for a period of 12 months at room temperature led to a decrease in vitamin C content, TPC, antioxidant capacity, while total soluble solids (TSS) and carotenoids increased during storage. The results of organoleptical attributes showed that the formulas O11, O1 had the highest score of color and odor respectively while O7 recorded maximum score for taste, texture and bitterness respectively. Statistical analysis showed that storage intervals and treatments had a significant (p < 0.05) effect on sensory quality of diet jam. The organoleptical characteristics were affected with the extension of shelf-life. Addition of stevioside and sucralose to formulate the low-calorie jam increased total phenol and antioxidant capacity, improved color, taste and produced targeted low-calorie jams. The use of sweeteners such as fructose, sucralose and stevioside in the manufacture of orange diet jam was shown to be satisfactory, resulting in low-calorie jams, improved the quality and could be produced commercially.