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The effects of UV-C irradiation (at doses of 8.16, 10.93, 16.17, and 33.29 mJ/cm2) on the physicochemical and microbiological properties of Agave tequilana Weber extracts at various pH values (4.5, 5.5, and 6.5) were evaluated. Thermal treatment (TT) was used as a control (85 &deg, C for 30 s). Both processed (UV-C or TT) and unprocessed (UP) extracts were investigated. The UV-C dose and the pH significantly (p &lt, 0.05) affected the inactivation of total coliforms (TC), total aerobic mesophiles (TAM), and yeasts and molds (YM). UV-C doses of 10.93 mJ/cm2 at pH 4.5 and 33.29 mJ/cm2 at any agave extract pH completely inactivated the native microbial load compared to TT. The total polyphenols (TP), antioxidant activity (AA), and sugar content did not change in the agave extracts at any dose, but the total flavonoid (TF) content decreased at doses &gt, 16.17 mJ/cm2 at the evaluated pH values. Although the color of the agave extracts (L*, a*, and b*) was significantly affected, the total color difference (∆E) did not change after processing compared to the ∆E in the UP extracts. TT further reduced all the physicochemical properties of the agave extracts compared to UV-C processing. The results suggest that UV-C continuous flow technology can be used to stabilize agave extracts at doses of 10.93 mJ/cm2 and pH 4.5, while preserving their functional properties.

Effects of smoking time and temperature on optimal chipotle pepper production were evaluated and optimized using the response surface methodology. Batches of red jalapeno peppers were smoked under different temperatures (65.8, 70, 80, 90, 94.1C) and times (0.96, 2, 4.5, 7, 8 h). Afterward, samples were evaluated for moisture, rheological properties and total phenols. Samples were then dried from 80C to between 0.123 and 0.204 kg H2O/kg dry matter and evaluated for rheological properties, texture, rehydration, color and phenols. Phenol content, rehydration ratio, firmness of peppers, and rheological properties and color of puree were affected (P < 0.05) by both temperature and time. Best smoking conditions used temperatures of 74–79C, and times between 8.0 and 7.4 h resulting in viscosities of 5.1– 6.5 Pa·s with phenol content of 110–120 mg/kg, rehydration ratios of 3.7–4.1, firmness of 1.27–1.49 N and acceptable color. Smoking time was significantly reduced and quality maintained.

Diced green bell pepper was blanched twice, once at 51-79 °C for 19-61 min, and once at 95 °C for 3 min, and dried. The firmness of rehydrated samples was measured by puncture, and optimum conditions assessed by response surface methodology. The optimized model showed that, blanching at 65 °C for 49 min gave a 64% increase in puncture force over the control. The optimum temperature was used to evaluate the effect of adding CaCl 2 . The dices were blanched twice, once at 65 °C for 3 min in either 0 or 4% CaCl 2 , secondly in either 0 or 2% CaCl 2 solution at 95 °C for 3 min. In the second case the dices had been held at room temperature for 0-30 min before treatment. Adding CaCl 2 increased puncture force significantly (P ≤ 0.05). The best results, those which gave greatest firmness, were obtained by blanching at 65 °C for 3 min in 4% CaCl 2 , holding for 16 min after blanching, followed by a secondary blanching at 95 °C in 2% CaCl 2 . Du poivron vert en cube a ete blanchi deux fois puis seche. La fermete du poivron rehydrate a ete mesure et les conditions optimales ont ete determinees: le blanchiment a 65° pendant 49 min donne les meilleurs resultats. Le poivron en cube a ensuite ete blanchi a 65° pendant 3 min.puis 95° pendant 3 min. en presence de chlorure de calcium a concentration variable, a chaque fois. Les meilleurs resultats sont obtenus pour CaCl 2 a 4% puis CaCl 2 a 2% pour le deuxieme blanchiment.

Jalapeño peppers incur texture changes during thermal processing due to loss of turgor pressure, tissue softening, and pectin solubility in the cell wall, which affects their quality and acceptability as a processed product among consumers. The objective of this work is to evaluate the effect of stepwise blanching with calcium chloride solution on firmness, calcium absorption and microstructural changes of jalapeño peppers. Batches of 1 kg of pepper halves were blanched at 65 °C for 4 min at different concentrations of CaCl2 (0, 0.075, 0.15 and 0.3 mol/L). After blanching, the peppers were removed, placed in plastic bags and submerged in a water bath at 65 °C for different holding times (0, 15, 30 and 45 min). Then the peppers were blanched again in an acidified solution at 96 °C for 3 min to remove enzymatic activity. Afterwards, peppers were packed in glass containers with brine at 95 °C and pasteurized at 85 °C for 10 min. The product was stored for 10 days at room temperature, then analyzed for texture, calcium absorption, pH, acidity, and microstructural changes. Results showed that CaCl2 concentration and blanching improved firmness with a maximum value of 3.68 N, a 4.3-fold increase over control. Calcium absorption increased with CaCl2 concentration reaching a maximum of 0.68 g of Ca2+ per kg of samples. Microscopy showed reduced cell wall damage in the samples that were blanched in 0.3 mol/L of CaCl2 at 45 min of holding time. The optimum processing conditions determined in thisstudy can be used for improving the firmness of peppers., Tijekom toplinske obrade mijenja se tekstura „jalapeño” paprika zbog gubitka turgora, mekšanja tkiva i topljivosti pektina u staničnim stijenkama, što utječe na njihovu kakvoću i prihvatljivost među potrošačima. Svrha je ovoga rada bila procijeniti učinak postupnog blanširanja u otopini kalcijeva klorida na čvrstoću tkiva, apsorpciju kalcija i mikrostrukturalne promjene „jalapeño” paprika. Šarže od 1 kg polovica paprika blanširane su 4 minute na 65 °C pri različitim koncentracijama CaCl2 (0; 0,075; 0,15 i 0,3 mol/L). Nakon blanširanja paprike su stavljene u plastične vrećice i potopljene u vodenu kupelj na 65 °C tijekom 0, 15, 30 i 45 min. Zatim su radi inaktivacije enzima 3 minute blanširane u zakiseljenoj otopini pri 96 °C, te pakirane u staklenke s rasolom (pri 95 °C) i pasterizirane na 85 °C tijekom 10 min. Naposljetku su 10 dana skladištene na sobnoj temperaturi, nakon čega je analizirana njihova tekstura, apsorpcija kalcija, pH, kiselost i mikrostrukturalne promjene. Rezultati pokazuju da CaCl2 i blanširanje poboljšavaju čvrstoću tkiva 4,3 puta (na maksimalnih 3,68 N), u usporedbi s kontrolnim uzorkom. Povećanjem koncentracije CaCl2 povećala se apsorpcija kalcija (maksimalno 0,68 g Ca2+/kg paprika). U uzorcima blanširanim 45 min u otopini CaCl2, koncentracije 0,3 mol/L, mikroskopski je utvrđeno manje oštećenje staničnih stijenki. Stoga je zaključeno da se čvrstoća paprika može poboljšati optimiranjem uvjeta prerade.