Fidel Guevara-Lara

Physicochemical, Nutritional, and Functional Characterization of Fruits Xoconostle (Opuntia matudae) Pears from Central‐México Region

Xoconostle cv. Cuaresmeño (Opuntia matudae) has attracted domestic and international industry attention; however, variations of composition from xoconostle structures have not been evaluated. Industries discard the pulp (endocarp) and peel (pericarp) as wastes and utilize the skin (mesocarp), which is the edible portion. The physicochemical, nutritional, and functional characterization of structures from xoconostle pear from 3 major sites of production in Mexico were assessed. Skin yield ranged from 58% to 64% and was higher to that of peel (22% to 24%) and pulp (12% to 18%) yields. pH, degrees Brix, and acidity were similar among xoconostle structures. Total fiber showed by peel (18.23% to 20.37%) was 2-fold higher than that of skin. Protein and ether extract were higher in xoconostle pulp compared to that showed by peel and skin. Iron content of xoconostle peel (6 to 9.6 mg/100 g, DWB) was higher to that of skin and pulp and prickly pear pulp. Soluble phenols of peel (840 to 863 mg GAE/100 g, DWB) were almost similar to that of skin (919 to 986 mg GAE/100 g, dry weigh basis); meanwhile, ascorbic acid concentration of skin was 2-fold higher compared to that of peel. The phenolic fraction of xoconostle structures consisted of gallic, vanillic, and 4-hydroxybenzoic acids; catechin, epicatechin, and vanillin were also identified by high-performance liquid chromatography-didoe array detection (HPLC-DAD). Xoconostle peel showed higher antioxidant activity (TEAC) compared to that of skin (2-fold) and pulp (6-fold) of commonly consumed fruits and vegetables. The potential of xoconostle peel and pulp for the production of feed or food is promissory. Practical Application: Outstanding nutritional and functional properties of xoconostle cv. Cuaresmeño fruits are demonstrated. Increased consumption could contribute positively to improve the diet of rural and urban consumers. The high fiber, mineral, and antioxidant components of xoconostle peel and pulp suggest that these fruit structures, which are currently discarded as waste, have promissory use as feed or food by industry.

Effects of two fibrolytic enzyme mixtures on growth performance, digestion and ruminal fermentation in lambs fed corn stover based diets.

The objective of this study was to compare the effects of two fibrolytic enzyme mixtures (Fibrozyme and Promote) on growth performance, digestion and ruminal fermentation in lambs fed corn stover based diets. Forty-two crossbred (Black Belly×Dorper) lambs (20±1.6 kg) were randomly assigned to three treatments defined as Control (no enzymes), Fibrozyme (Alltech, Nicholasville, KY, USA), and Promote (Cargill Corp., Minneapolis, MN, USA). Growth performance evaluation lasted 55 days. On day 55, rumen fluid samples were obtained. Both Fibrozyme and Promote improved growth performance, feed conversion and digestion as compared to Control. Enzymes increased total volatile fatty acids, but only Fibrozyme increased molar proportion of propionate, decreased molar proportion of butyrate, and reduced the acetate: propionate ratio. It is concluded that both Fibrozyme and Promote improved growth performance and digestion in lambs fed high-forage diets.

Effect of aguamiel (agave sap) on hematic biometry in rabbits and its antioxidant activity determination

In this work, we analysed the effect of aguamiel (sap from Agave salmiana) on haematic biometry in rabbits as well as its antioxidant activity with the objective of determining its nutritional value. Nine male Landrace 55-day-old rabbits were sorted into three groups of three rabbits each, which had access to fresh aguamiel, boiled aguamiel and water instead of aguamiel. Commercial rabbit food was supplied ad libitum to each experimental unit. Fresh aguamiel promoted weight increases of about 13% by the seventh week. Haemoglobin counts increased by 4.5% and 9% when rabbits were fed with fresh and boiled aguamiel, respectively. Haematocrit counts increased from 2.6% to 5.3%. Mean corpuscular volume did not show a change. Mean corpuscular haemoglobin significantly increased up to 12% above that previously reported on rabbits. Observed Fe (fixed to transferrin), transferrin and ferritin content increased slightly when fresh aguamiel was included in the diet, as compared to the control. In bone, Fe increased 79.3% (boiled aguamiel) while P increased 23.6% (fresh aguamiel). In antioxidant activity determination, the aguamiel showed 20% with respect to that found in coffee and/or grape juice (commercial beverages with a high antioxidant capability), 226.2 µmol gallic acid equivalent and 35.1 mg ascorbic acid in 250 mL, respectively. These results showed that aguamiel is an innocuous beverage to feed animals, conferring some beneficial properties, and it could be considered as a nutraceutical product.

Effect of huitlacoche (Ustilago maydis DC Corda) paste addition on functional, chemical and textural properties of tortilla chips

This study analyzed the addition of huitlacoche paste (HP) in baked tortilla chips (TC), evaluating its effects on functional, physicochemical and structural changes during processing. Two blue corn grains were nixtamalized, stone milled, air dried and milled to obtain flour; commercial blue corn flour (TM1) and commercial TC (TM2) were used as controls. Additions of 0, 3, 6 and 9% of HP were formulated; masas were prepared at 55% moisture content (MC), precooked and baked in an industrial machine. TC crispiness was influenced by grain characteristics and percentage of HP. Huitlacoche paste addition caused an increase in total dietary fiber (from 5.27 to 14.54%), total soluble phenolics content (from 17.52 to 37.60 mg GAE/100 g) and antioxidant capacity (from 6.74 to 7.98 μmol TE/g) in TC. Results suggest that tortilla chips added with huitlacoche can be an alternative to prepare this traditional edible fungus and produce healthier snacks, not fried and enriched with bioactive compounds.