Refine
Document Type
- Article (4)
Language
- English (4)
Is part of the Bibliography
- yes (4)
Keywords
- Inactivation (2)
- Chemical properties (1)
- Electron beam (1)
- High pressure processing (1)
- Irradiation (1)
- Microorganisms (1)
- Modeling (1)
- Mycotoxin (1)
- Optimization (1)
- Paste (1)
Institute
- Fakultät AuL (4)
The impact of pulsed light (PL) treatment on naturally occurring microorganisms, mycotoxins, and on physicochemical properties in red pepper powder was investigated. Powder samples were exposed to different PL treatments up to 61 pulses, with fluence ranging from 1.0 to 9.1 J/cm2. The highest fluence applied (9.1 J/cm2, 61 pulses, 20 s) resulted in 2.7, 3.1, and 4.1 log CFU/g reduction of yeasts, molds, and total plate counts (TPC), where initial microbial loads were 4.6, 5.5, and 6.5 log CFU/g, respectively. At the same fluence intensity, a maximum reduction of 67.2, 50.9, and 36.9% of aflatoxin B1 (AFB1), total aflatoxins (AF), and ochratoxin A (OTA) were detected, respectively. Proportional increase in temperature of the samples was observed from the absorbed PL energy, reaching maximum of 59.8°C. The inactivation of investigated microorganisms and mycotoxins followed first-order kinetics (R2 > 0.95). The fluence intensity at 6.9 and 9.1 J/cm2 did not cause degradation, but rather a significant (p < .05) and apparent increase of total phenols. Total color difference (ΔE*) revealed only “slight differences,” compared to the untreated sample. In conclusion, higher reduction of microbial load and mycotoxins in red pepper powder could be achieved, when higher treatment intensity was applied. This suggests the PL as a potential technology for decontamination of red pepper powder and other spice powders.
The study aimed to investigate inactivation of naturally occurring microorganisms and quality of red pepper paste treated by high pressure processing (HPP). Central composite rotatable design was employed to determine the impacts of pressure (100–600 MPa) and holding time (30–600 s). HPP at 527 MPa for 517 s reduced aerobic mesophilic bacteria count by 4.5 log CFU/g. Yeasts and molds counts were reduced to 1 log CFU/g at 600 MPa for 315 s. Total phenols, carotenoids and antioxidants activity ranged from 0.28 to 0.33 g GAE/100 g, 96.0–98.4 mg βc/100 g and 8.70–8.95 μmol TE/g, respectively. Increase (2.5–6.7%) in these variables was observed with increasing pressure and holding time. Total color difference (ΔE∗) values (0.2–2.8) were within the ranges of ‘imperceptible’ to ‘noticeable’. Experimental results were fitted satisfactorily into quadratic model with higher R2 values (0.8619–0.9863). Optimization process suggested treatment of red pepper paste at 536 MPa for 125 s for maximum desirability (0.622). Validation experiments confirmed comparable percentage of relative errors. Overall, this technique could be considered as an efficient treatment for the inactivation of microorganisms that naturally occur in red pepper paste with minimal changes in its characteristics.
Red pepper (Capsicum annuum L.) is one of the major spices consumed globally, recognized for its aroma and nutrient properties, and it has a major economic value for high producing countries. However, characterization of its techno-functional properties and in-depth understanding of oxidative stability is needed to produce food of high quality and stability. Thus, this work focused on the chemical, functional, thermal, oxidative stability and rheological properties of red pepper powder and paste. Experiment was designed in a Completely Randomized Design (CRD) fashion. The red pepper powder contained 14.50 g/100 g, 44.00 g/100 g and 7.57 g/100 g of crude fat, crude fiber and ash, respectively. The concentration of total phenols, carotenoids and antioxidants activity of the powder were 1.04 g GAE/100 g, 374 mg βc/100 g and 38.61 μmol TE/g, respectively. Functional properties showed lower bulk density (395.1 kg/m3) and higher tapped density (583.4 kg/m3) indicating the higher compressibility of the powder. In contrast, Hausner ratio (1.48), Carr’s index (32%) and angle of repose (45°) indicated poor flowability of the powder. Particle size distribution also indicated that the volume weighted mean values D[4,3] of the powder and paste were 262.20 and 201.46, respectively. Emulsifying capacity of the powder was 47.5%. Oil and water absorption capacities varied from 1.41 to 1.73 and 0.86 to 2.29 g/g of initial weight, respectively. Higher glass transition temperature was observed for the powder (62.54°C) than the paste (45.64°C). The induction period indicated that red pepper was more stable against oxidation in powder (5.2 h) than in the paste form (3.2 h). Rheological analysis revealed that the paste exhibited shear-thinning behavior. Overall, understanding of the properties of red pepper could contribute to enhance quality.
This study reported the impact of electron beam (e-beam) treatment on microbiota and mycotoxins naturally present in red pepper powder and physicochemical quality changes. Treatment at 6 kGy indicated significant (p < 0.05) decontamination of yeasts and molds by 3.0 and 4.4 log CFU/g, respectively. A reduction of 4.5 log CFU/g of total plate counts (TPC) was observed at 10 kGy for 23 s. Fungal inactivation followed first-order kinetics while TPC better fitted with Gompertz function (R2 = 0.9912). E-beam treatment was not efficient for the degradation of aflatoxins but indirectly controlled their production by inactivation of mycotoxigenic molds. Indeed, reduction of 25% ochratoxin A was recorded at 30 kGy retaining >85% of total phenols, carotenoids and antioxidants activity. Moreover, treatment impact on total color difference (ΔE*) indicated ‘slight differences’. Overall, e-beam treatments up to 10 kGy were efficient in decontaminating the natural microbiota without detrimental effects on the physicochemical qualities of red pepper powder.