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Whole and fresh-cut produce are minimally processed and susceptible to microbial contamination. This study evaluated the survival or growth of L. monocytogenes on peeled rinds, and fresh-cut produce at different storage temperatures. Fresh-cut fruits and vegetables, including cantaloupe, watermelon, pear, papaya, pineapple, broccoli, cauliflower, lettuce, bell pepper, and kale (25 g pieces) were spot inoculated with 4 log CFU/g of L. monocytogenes and stored at 4 or 13°C for 6 days. Cantaloupe and bell pepper rind disks (20 cm2), mimicking whole produce were inoculated with low inoculum level (4 log CFU/mL) and high inoculum level (6 log CFU/mL) and stored at 24°C up to 8 days and 4°C up to 14 days, respectively. L. monocytogenes counts on fresh-cut pear samples stored at 4°C increased significantly by 0.27 log CFU/g. However, Listeria levels on kale (day 4), cauliflower (day 6), and broccoli (day 2) were significantly reduced by 0.73, 1.18, and 0.80 log CFU/g, respectively, at 4°C. At 13°C, the bacterial counts increased significantly after a day of storage on fresh-cut watermelons (increasing by 1.10 log CFU/g) and cantaloupes (increasing by 1.52 log CFU/g). Similar increases were observed on pears (1.00 log CFU/g), papayas (1.65 log CFU/g), and green bell peppers (1.72 log CFU/g). Pineapple samples did not support the growth of L. monocytogenes at 13°C with a significant reduction of 1.80 log CFU/g by day 6. L. monocytogenes levels significantly increased in fresh-cut lettuce at 13°C but remained stable on kale, cauliflower, and broccoli after 6 days of storage. Stable population was observed also on cantaloupe rinds up to 8 days at 24°C. While on the outer surface of bell peppers, the population level decreased below the detectable limit of the test (10 CFU/20 cm2) after 14 days of storage at 4°C. The results demonstrated variable survival behavior of L. monocytogenes on freshcut produce with produce type and storage temperature. [ABSTRACT FROM AUTHOR]

Background and objectives: Recently, the LSU AgCenter developed a high‐protein rice cultivar (Oryza sativa L.) called Frontière, which is non‐GMO and it is the first of its kind to be developed for commercial applications worldwide. As a result, the physicochemical and thermal properties of the Frontière rice flours and commercial rice flours were analyzed using differential scanning calorimetry (DSC) and Brabender Viscometer (RVA). Rheological properties were determined using a rheometer by small amplitude oscillatory shear (SAOS) and steady shear. Cupcakes were developed using these flours, and the texture and color were determined. For the high‐protein rice flours (white and brown), thermal, rheological, pasting, and chemical attributes were evaluated (p <.05) and compared with commercial rice flours. Findings: Gelatinization temperatures (Tp) varied between 70.90℃ and 76.33℃, and the enthalpies (∆H) ranged from 3.29 to 7.60 J/g. In the pasting properties by Rapid Visco Analysis (RVA), the values of peak viscosity ranged from 2,322 to 2,344 cP. In addition, proximate composition of high‐protein rice flours (moisture, ash, fat, and protein) varied as follows: 12.39%–13.49%, 0.74%–1.83%, 0.66%–1.39%, and 10.23%–12.21%, while starch and amylose levels were 65.41%–75.15% (dry basis) and 10.19%–20.57%. Conclusions: The rheological properties were mainly affected by apparent amylose and protein content, and weaker gel behaviors were observed for brown rice flour dispersions. As for the cupcakes characteristics, the texture and color were influenced by the type of flour used. Significance and novelty: Flour from a new higher protein rice variety was characterized for physiochemical properties and tested for use in gluten‐free cupcakes. This information is useful to ingredient companies who may be interested in the use of this flour in bakery products. [ABSTRACT FROM AUTHOR]

Ascorbic acid is less effective than alpha-tocopherol in quenching singlet oxygen during the oxidation of vitamin D2 in the presence of 15 ppm riboflavin. This could be attributable to the fact that the stability of ascorbic acid is determined by the pH. This research aimed to prove the hypothesis that riboflavin-photosensitized singlet oxygen oxidation of vitamin D takes place. It also sought to establish the kinetics and mechanisms for quenching singlet oxygen oxidation of vitamin D. Oxidation of vitamin D was not seen in samples without riboflavin stored in the light or in samples with riboflavin stored in the dark.

There is a need for acceptable gluten-free foods that provide greater protein. Rice is used in gluten-free products and new higher protein rice varieties now exist. Stores surveyed for products with rice flour as the main ingredient showed 36% snacks and 13% breads, with baked snacks 1.3 g protein/serving. Bread was chosen as the focus for testing higher protein rice flour (HPR). HPR were compared to commercial rice flours (CW) for pasting properties, protein, fat, and fiber content. Gluten-free bread was prepared and tested for color and texture. A consumer sensory study rated appearance, aroma, texture, and taste of the breads. Brown and white HPR were 10.1% and 9.25% protein. There were no differences in acceptance of breads made with any flour. Health benefit information for HPR breads increased purchase intent. Rice flour with greater protein can be used in gluten-free rice flour baked goods without affecting properties. [ABSTRACT FROM AUTHOR]

A comparison was made on the extraction yields of lutein from egg yolk using both hexane solvent (SOL) and ultrasound-assisted solvent (UA-SOL) extraction methods at different levels of saponification. Results revealed that alkaline significantly affected stability of lutein in egg yolk and resulted in underestimation of its concentration.

Availability of prepared foods in today's market that provide healthy diets for consumers 65 and older is lacking. A general market survey, covering nine grocery stores and approximately 400 items in the greater Baton Rouge area, was conducted on snack foods, frozen meals, and dry products. Two other surveys included a survey of pasta items and a blind consumer survey targeting consumers ages 65 and older. In each survey, products were categorized as high, medium, or low in fiber and low, medium, or high glycemic load. Prepared meals with high levels of dietary fiber and low glycemic loads were found to be rare. Results from the blind consumer survey found that key unsatisfactory characteristics in commercial products were texture and color. Our research suggests that there is a need for the development of healthier prepared meals in the grocery store market. [ABSTRACT FROM AUTHOR]

Beans, an excellent source of dietary fiber and protein, have potential for lowering glycemic load. Prepared meals with high dietary fiber and low glycemic load were rare in a market survey in Baton Rouge, LA. The purpose of this research was to increase fiber and decrease glycemic load in ravioli through substitution with bean flour from pinto, navy, or black beans mixed with wheat flour. Navy bean flour mixed with wheat flour resulted in similar texture to wheat flour at up to 50% substitution level. Calculated proximate analysis of raviolis with 50% and 75% navy bean flour predicted a 14% to 21% DV increase in dietary fiber and a 7- to 10-gram decrease in glycemic load. Sensory evaluation found that the color, texture, aroma, appearance, and liking preferences were not significantly changed by 50% substitution of navy bean flour. An acceptable higher fiber, lower glycemic index ravioli was produced. [ABSTRACT FROM AUTHOR]