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Enzymatic liquefaction conditions were evaluated to obtain fructan from wild sotol plant (Dasylirion wheeleri) using the commercial preparation Pectinex Ultra SP-L. Ground sotol head was subjected to enzymatic extraction at various enzyme activities (0.0–175.73 U/mL) and fresh sotol concentrations (4.47–28.52 g/100 mL) at 30 °C for 8 h, using the response surface methodology to optimize the fructan extraction. Reducing sugars (RS), total carbohydrates (TC), fructan content (FRU), fructan profile, and the average degree of polymerization (DPn) were evaluated. Additionally, RS release kinetics and the enzyme rate constant (V0) were calculated. Enzyme concentration and substrate significantly affected (P 87.87 U/mL enzyme, and fructan extraction was maximal (39.08 g/100 g d.m.) at 83.04 U/mL enzyme and 6.70 g/100 mL substrate. V0 and RS content exhibited similar trends. DPn increased as substrate concentration decreased. Optimal enzymatic liquefaction conditions were 11.6–45.6 U/mL enzyme and 9.15–12.6 g/100 mL sotol, yielding elevated fructan (38.58 g/100 g d.m.), DPn of 8–10, and low fructose (1.8 g/100 g d.m.) and glucose (2.2 g/100 g d.m.) contents. These results demonstrate the feasibility of enzymatic liquefaction for extracting fructans from sotol heads without modifying the molecular structure.

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.

The present investigation evaluated the chemical and thermal properties using lime and alternative calcium salts, and their effect on the characteristics of masa and tortilla obtained in a two-step nixtamalization process. White dent corn was cooked in calcium hydroxide solution (1.2% [w/v]; 1:3 maize : water ratio) at 80C (30 min), and the calcium hydroxide was replaced either by calcium chloride or lactate at calcium equilibrated concentration (30 min), and steeped in a cooking solution for 2,400 min. Grains were analyzed for water and calcium absorption, and apparent diffusion coefficients were calculated. Thermal properties of flour made from these grains were also determined. Additionally, the masa and tortilla made with nixtamalized corn flours were analyzed for texture and color, and an acceptability test was performed on the tortilla. Water absorption showed a notable increase during cooking, approaching an asymptotic maximum absorption after 8 h of steeping for all treatments. The maximum calcium absorption was obtained in stepwise nixtamalization with solutes of CaCl2 and C6H10O6Ca. The water apparent diffusion coefficients were adequately described by Fick's model and it was found that C6H10O6Ca showed the highest value (5.5901 × 10−10 m2/s), while that for calcium diffusion the model gave low fits. The thermal analysis showed that gelatinization temperatures were affected significantly (P

The effects of blanching and drying treatments on stability, physical properties, and antioxidant activity of apple pomace polyphenols were evaluated. Blanched and unblanched apples were extracted, and the pomace was dried in a cabinet dryer at a speed of 3 m/s at 50 °C, 60 °C, 70 °C, and 80 °C. The color, total phenolics, flavonoids, individual polyphenolic compounds, anthocyanins, and total antioxidant activity were analyzed. The blanching process caused a major retention in color, total polyphenolic content, and total flavonoid content for fresh apple pomace when compared with fresh unblanched pomace. Drying of either fresh blanched or fresh unblanched pomace caused a significant reduction (P < 0.05) in total polyphenol and flavonoid content leading to a reduction in the total antioxidant activity. When compared with the unblanched treatment, drying the blanched pomace at 80 °C resulted in a product with significant amounts of total phenolics, flavonoids, and antioxidant activity. The individual phenolic compounds were significantly increased (P < 0.05) in blanched pomace that was not dried when compared with unblanched samples. Drying blanched apple pomace did not cause a significant change in the concentration of individual polyphenolic compounds, but drying unblanched apple pomace caused a reduction in the concentrations of epicatechin and caffeic acid, with an important reduction in p-coumaric acid at temperatures higher than 60 °C. However, the drying process caused a significant reduction in the antioxidant capacity. Therefore, a combination of blanching and drying processes for apple pomace results in a product that maintains antioxidant capacity.

White dent corn was nixtamalized in a Ca(OH) 2 [1.2% (w/v)] solution, at a 1:3 corn/water ratio, at 70, 80, 90 and 100 °C for 1 h, with and without mechanical agitation. After cooking the nixtamalized grains were steeped for 48 h. During cooking, kinetics of soluble and suspended solids and total sugar were determined, while that in the grain was determined the pericarp removed. During steeping, water and calcium absorption kinetics were determined in grains and apparent diffusion coefficients were calculated using Fick’s second law. Changes in thermal properties were determined. Cooking temperature and agitation had significant effects on the chemical and physical properties of grains and nejayote. Soluble and suspended solids and total sugar in nejayote showed a linear trend over time for different temperatures, while pericarp removal during both cooking and steeping reached over 90%. Cooking temperature had a significant effect on water and calcium absorption in grains. Calcium and water diffusion were described adequately using Fick’s model. Water and calcium diffusion coefficients values were 2.07–3.52 × 10 −10 m 2 s −1 and of 0.332–1.43 × 10 −10 m 2 s −1 , respectively. Gelatinization temperature and enthalpy were significantly influenced by the temperature and time of the cooking.

Mass transfer and physical attributes of red bell pepper were evaluated. Pepper strips were placed into brine of constant concentration at different temperatures (25–55 °C) with immersion times ranging from 15 to 480 min with and without ultrasound treatment. Diffusion coefficients were evaluated for calcium, sodium, citric acid, soluble and total solids, impregnation and water loss. Firmness, kinetic coefficients and color were determined for each treatment. Ultrasound increased the uptake of solutes ( p −10 m 2 /s, 7.26 × 10 −10 m 2 /s and 14.42 × 10 −10 m 2 /s, respectively. These increases may be attributed to increased cell wall permeability, facilitating transport of water and solute, as evidenced by product firmness, where ultrasound treatments had a negative effect on firmness.

The effect of low-temperature blanching and drying processes on the ultrastructural and physical properties of Anaheim chilli pepper was studied and optimum conditions to provide a final product with maximum firmness were determined. Lots of Anaheim pepper were blanched in water for 4min at 48, 55, 65, 75 and 82 ◦ C and maintained for hold times of 35, 45, 60, 75 and 85min, blanched again for 4min at 96 ◦ C and dehydrated at 53, 60, 70, 80 and 87 ◦ C. After treatment the samples were rehydrated in water at 30 ◦ C. Rehydration ratio, texture and structural changes were evaluated. Optimisation used a second-order rotatable central composite design. Texture and rehydration ratio were affected by blanching temperature and the interaction of blanching temperature with hold time (p ≤ 0.05); drying temperature did not show a significant effect. The best results, ie those which gave greatest firmness, were obtained by blanching at 64 ◦ C for 4min, holding for 55min after blanching, followed by a second blanching at 96 ◦ C for 4min and then drying at 70 ◦ C. Evaluation of the rehydrated dried pepper by microscopy showed that low-temperature blanching close to the optimum conditions provided a protective effect in maintaining cell wall integrity. The results of processing increased firmness in the rehydrated product by a factor of 1.97.  2003 Society of Chemical Industry

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.