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Saffron, the dried stigma of the Crocus sativusL. flower, is a highly valuable spice widely used in the Mediterranean and West and South Asia. The stability and quality of saffron are influenced by factors such as harvest conditions, post-harvest handling, and storage. This review addressed technical information gaps and provided guidelines for optimizing saffron drying to ensure the best quality. It covered diverse drying methods, including hot air-dryer, vacuum oven dryer, electric oven drying, hybrid photovoltaic-thermal dryer, infrared dryer, microwave dryer, refractance-window drying, freeze drying, and fluidized bed dryer, emphasizing their impact on the drying process and final product quality. The review also discussed the theory of saffron dehydration and summarized experimental findings from the past few decades. Additionally, it integrated important aspects of saffron production and processing, such as harvesting and pretreatments like pulsed electric field and cold plasma, highlighting the need to control temperature, humidity, and airflow to preserve saffron’s valuable bioactive compounds and sensory properties. Ultimately, this comprehensive review aimed to inform and guide saffron producers and researchers in selecting and optimizing drying techniques to maintain and enhance the quality of this precious spice.

This study comprehensively evaluated the effects of Lactiplantibacillus plantarumT1 and CSK (ropy and non-ropy phenotypes), on flavour, and nutrient metabolites of fermented milks using gas chromatography-mass spectrometry and non-targeted metabolomics. The microrheological analysis showed that the protein gelation time of CSK fermented milk was earlier (5.2 h) than that of T1 (7.0 h), while the fermented milk by T1 had higher elastic modulus. Fermentation by both strains significantly enhanced the antioxidant activity of the fermented milk, including scavenging capabilities against ABTS, DPPH, and hydroxyl radicals. Meanwhile, fermentation by two strains produced various volatile flavor compounds (hexanoic acid, caprylic acid, capric acid, nonanal, decanal, 2-heptanone and 2-nonanone, etc.), and L. plantarumCSK displayed more stronger acid production capacity. In addition, a total of 397 shared metabolites and 81 unique metabolites were identified by untargeted metabolomics analysis of the two groups of fermented milks, mainly including lipids and lipid-like molecules (66, 27.27%), organic heterocyclic compounds (40, 16.53%), phenylketones and polyketones (23, 9.5%), and organic acids and their derivatives (49, 20.25%). Furthermore, both strains significantly elevated the amino acid nutritional levels in the fermented milk, conferred an abundance of active metabolites such as niacin and nicotinamide. During the fermentation, L. plantarumCSK notably produced antioxidant fumaric acid and exhibited higher fatty acid metabolism compared to L. plantarumT1. Overall, this study provides some practical basis for the development of fermented cow's milk with good antioxidant activity and high nutritional quality using different phenotypes of L. plantarum.

Ultrasonication technology was utilized for extraction of effective components from Nepeta (Nepeta binaludensisJamzad). Response surface methodology was employed in order for investigation the effects of independent process variables (ultrasonic extraction time (UET, min): 5, 10 and 15 min, ultrasound amplitude (UA, %): 20, 60 and 100%, ultrasonic extraction temperature (UEC, °C): 25, 35 and 45 °C and ultrasonic duty cycle (UDC, %): 20, 60 and 100%) on the yield (Y), total phenolic compounds (TPC), half maximal of radical (1,1-diphenyl-2-picryl hydrazyl, DPPH) scavenging activity (IC50) and ferric reducing-antioxidant power (FRAP) of ethanolic Nepeta extract. According to Derringer’s desired function approach, the optimal conditions based on both individual and combinations of all process variables were UET 15 min, UA 60%, UEC 25 °C and UDC 60%. At this optimum condition, the Y, TPC, IC50and FRAP of the ultrasound-assisted extract (USx) were found to 10.93%, 402.63 mg GA/kg, 0.33 mg/mL and 2838.34 µmol Fe2+/kg, respectively which were well matched with the predicted values. The evaluation of antioxidant activity (IC50and FRAP) indicates that the phenolic compounds from Nepetapossess significant antioxidant activity. Also, HPLC analysis revealed that at optimal condition of UAE, the quantity of caffeic acid (85.71%), rutin (3550%) and rosemarinic acid (468.62%) in extract increased in comparison with conventional method (solvent extraction).

The oxidative stability and oxidation kinetics of pure soybean oil (PSO) supplemented with 0.5–6% of pulse electric field ethanolic extract (PEFx) of Nepeta (Nepata binaludensisJamzad) or 100 ppm of butylated hydroxytoluene (BHT) were evaluated at 100–120 °C. The oxidative stability of PSO decreased with increasing temperature and improved significantly (p< 0.05) by added PEFxat the levels 0.5% and higher. The reaction rate constants increased linearly with increasing temperature from 100 to 120 °C. The temperature coefficients of PSO with added PEFxat different concentrations ranged from − 3.37 × 10−2to − 4.79 × 10−2°C as compared with -2.79 × 10−2°C with BHT. The values of activation energies, temperature acceleration factors, activation enthalpies and entropies for oxidative stability of the PSO with added PEFxat different concentrations ranged from 92 to 100 kJ/mol, from 2.13 to 2.27, from 88.8 to 96.9 J/mol K and − 71.9 to − 91.1 kJ/mol, respectively, as compared with 66.5 kJ/mol and − 162 kJ/mol with added BHT.

This study evaluated the effects of four previously reported strains of Lactiplantibacillus plantarum(T1, CL80, CSK, and S-1A) with different phenotypic characteristics on the fermentation quality, flavor characteristics, and digestive properties of soy milk. The results showed that all four strains exhibited good gastrointestinal survival and Caco-2 cell adhesion probiotic characteristics. The total free amino acid content of fermented soy milk significantly increased from 27.57 mg/100 g to 41.28 mg/100 g, enriching the soy milk with acidity and increasing the volatile flavor compounds such as acetic acid, decanoic acid, and octanoic acid. The fermentation process effectively reduced the levels of volatile compounds associated with beany off-flavors, including 1-octen-3-ol, 1-nonanol, hexanal, heptanal, 2-octenal, furfural, and trans-2,4-decadienal. The gel texture and rheological analysis indicated that soy milk fermented with the viscous phenotypic strains T1 and CL80 exhibited higher water-holding capacity (95.45%, 93.64%) and apparent viscosity (916.39, 713.78 Pa s). Furthermore, in vitrodynamic digestion demonstrated that soy milk fermented with the viscous phenotypic strains was more easily digested during the gastric phase compared to the non-viscous strains. In the intestinal phase of digestion, soy milk fermented with the ropy phenotypic strains had significantly higher levels of small peptides compared to the non-ropy strains, which facilitated the transfer and absorption of nutrients. This study provides valuable insights into improving the nutritional flavor and digestive properties of soy milk through fermentation using Lactiplantibacillus plantarumstrains with different phenotypic characteristics.