@article{story_kopec_schwartz_harris_2010, title={An Update on the Health Effects of Tomato Lycopene}, volume={1}, ISBN={["978-0-8243-4901-1"]}, ISSN={["1941-1413"]}, DOI={10.1146/annurev.food.102308.124120}, abstractNote={Lycopene is a non-provitamin A carotenoid that is responsible for the red to pink colors seen in tomatoes, pink grapefruit, and other foods. Processed tomato products are the primary dietary lycopene source in the United States. Unlike many other natural compounds, lycopene is generally stable to processing when present in the plant tissue matrix. Recently, lycopene has also been studied in relation to its potential health effects. Although promising data from epidemiological, as well as cell culture and animal, studies suggest that lycopene and the consumption of lycopene containing foods may affect cancer or cardiovascular disease risk, more clinical trial data is needed to support this hypothesis. In addition, future studies are required to understand the mechanism(s) whereby lycopene or its metabolites are proven to possess biological activity in humans.}, journal={ANNUAL REVIEW OF FOOD SCIENCE AND TECHNOLOGY, VOL 1}, author={Story, Erica N. and Kopec, Rachel E. and Schwartz, Steven J. and Harris, G. Keith}, year={2010}, pages={189–210} } @article{valdez_lopez_schwartz_bulux_solomons_2001, title={Sweet potato buds: the origins of a "designer" food to combat hypovitaminosis A in Guatemala. Processing, vitamin A content and preservation characteristics}, volume={21}, ISSN={["0271-5317"]}, DOI={10.1016/s0271-5317(00)00264-5}, abstractNote={A Guatemalan version of sweet potato flakes, called “sweet potato buds” (SPB), was created from Ipomoea batata by the drum-drying technique used to create instant mash potatoes. The yield on the first production run was 11% and that on the second production run was 13%. The amount of β-carotene per weight was concentrated from 16.5 to 42.2 μg/g from the whole sweet potato to the dried flakes. On one occasion, the β-carotene concentrations in the common variety of Guatemalan yellow-pulp sweet potato was 42.2 μg/g or 7.0 retinol equivalents (RE)/g in the SPB and on another 57.5 μg/g or 9.6 RE. Thus, a usual serving of one ounce (28 g) of SPB provides from 196 to 269 RE or 49 to 67% of the daily recommended amount. With storage in plastic or foil packaging, the β-carotene levels fell steeply, to the point of extinction within 4 months, independent of the type of barrier or the addition of food-grade antioxidants.}, number={1-2}, journal={NUTRITION RESEARCH}, author={Valdez, C and Lopez, CY and Schwartz, S and Bulux, J and Solomons, NW}, year={2001}, pages={61–70} } @article{henry_puspitasari-nienaber_jaren-galan_breemen_catignani_schwartz_2000, title={Effects of ozone and oxygen on the degradation of carotenoids in an aqueous model system}, volume={48}, ISSN={["0021-8561"]}, DOI={10.1021/jf000503o}, abstractNote={The effects of ozone and oxygen on the degradation of carotenoids in an aqueous model system were studied. All-trans beta-carotene, 9-cis beta-carotene, beta-cryptoxanthin, and lycopene were adsorbed onto a C(18) solid phase and exposed to a continuous flow of water saturated with oxygen or ozone at 30 degrees C. Carotenoids were analyzed using HPLC with a C(30) column and a photodiode array detector. Approximately 90% of all-trans beta-carotene, 9-cis beta-carotene, and beta-cryptoxanthin were lost after exposure to ozone for 7 h. A similar loss of lycopene occurred in only 1 h. When exposed to oxygen, all carotenoids, except beta-cryptoxanthin, degraded at lower rates. The degradation of all the carotenoids followed zero-order reaction kinetics with the following relative rates: lycopene > beta-cryptoxanthin > all-trans beta-carotene > 9-cis beta-carotene. The major degradation products of beta-carotene were tentatively identified on the basis of their elution on the HPLC column, UV-Vis spectra, and electrospray LC-MS. Predominant isomers of beta-carotene were 13-cis, 9-cis, and a di-cis isomer. Products resulting from cleavage of the molecule were beta-apo-13-carotenone and beta-apo-14'-carotenal, whereas epoxidation yielded beta-carotene 5,8-epoxide and beta-carotene 5, 8-endoperoxide.}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Henry, LK and Puspitasari-Nienaber, NL and Jaren-Galan, M and Breemen, RB and Catignani, GL and Schwartz, SJ}, year={2000}, month={Oct}, pages={5008–5013} } @article{hadden_watkins_levy_regalado_rivadeneira_breemen_schwartz_1999, title={Carotenoid composition of marigold (Tagetes erecta) flower extract used as nutritional supplement}, volume={47}, ISSN={["0021-8561"]}, DOI={10.1021/jf990096k}, abstractNote={Commercially prepared marigold flower (Tagetes erecta) extract was saponified and analyzed for carotenoid composition. HPLC analyses were performed on two normal-phase columns (beta-Cyclobond and silica) and on a C(30) reversed-phase column. The extract contained 93% utilizable pigments (detected at 450 nm), consisting of all-trans and cis isomers of zeaxanthin (5%), all-trans and cis isomers of lutein, and lutein esters (88%). All were identified by chromatographic retention, UV-visible spectra, and positive ion electrospray mass spectrometry in comparison to authentic standards. Contrary to previous findings, insignificant levels (<0.3%) of lutein oxidation products were detected in the saponified extract. This compositional determination is important for the application of marigold extract in nutritional supplements and increases its value as a poultry feed colorant because it contains more biologically useful lutein compounds than previously believed.}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Hadden, WL and Watkins, RH and Levy, LW and Regalado, E and Rivadeneira, DM and Breemen, RB and Schwartz, SJ}, year={1999}, month={Oct}, pages={4189–4194} } @article{canjura_watkins_schwartz_1999, title={Color improvement and metallo-chlorophyll complexes in continuous flow aseptically processed peas}, volume={64}, ISSN={["0022-1147"]}, DOI={10.1111/j.1365-2621.1999.tb12265.x}, abstractNote={ABSTRACTFresh and frozen green peas were blanched in zinc solution (50 to 500 mg/L) and thermally processed in a particle cell reactor, which simulates a continuous flow aseptic processing system. The thermal process temperatures ranged from 121 to 145 °C at holding times from 0 to 20 min. The degradation of chlorophyll and the resulting formation of Zn‐pheophytin a and Zn‐pyropheophytin a were monitored. Quantitative analysis of the metallo‐chlorophyll complexes was performed by high‐performance liquid chromatography. Complex formation increased during heat processing and was dependent on the zinc concentration absorbed within the peas during blanching. At 130 to 145 °C, the formation of Zn‐pyropheophytin a increased and processing between 121 to 125 °C promoted the formation of Zn‐pheophytin a. Improvements in color relative to control samples suggested that the process might be applicable to two‐phase continuous aseptic processing of vegetables.}, number={6}, journal={JOURNAL OF FOOD SCIENCE}, author={Canjura, FL and Watkins, RH and Schwartz, SJ}, year={1999}, pages={987–990} } @article{emenhiser_watkins_simunovic_solomons_bulux_barrows_schwartz_1999, title={Packaging preservation of beta-carotene in sweet potato flakes using flexible film and an oxygen absorber}, volume={22}, ISSN={["0146-9428"]}, DOI={10.1111/j.1745-4557.1999.tb00927.x}, abstractNote={ABSTRACT Sweet potato flakes are potentially an affordable, shelf‐stable source of provitamin A β‐carotene. Because β‐carotene is susceptible to oxidative degradation, particularly in dehydrated food materials exposed to atmospheric oxygen, several packaging conditions were evaluated for enhancement of β‐carotene retention in sweet potato flakes during storage. The flakes were packaged in either a polypropylene film (high oxygen permeability) with air headspace or a nylon laminate film (low oxygen permeability) with air headspace, under vacuum, or with an Ageless oxygen absorber sachet enclosed. Packaged flakes were stored in the dark at ambient laboratory temperature (∼23C), and β‐carotene content was determined at intervals from 0 to 210 day storage using reversed‐phase liquid chromatography. Among the packaging conditions tested, β‐carotene retention was enhanced incrementally as the apparent availability of oxygen was reduced (nylon > polypropylene; oxygen absorber > vacuum > air headspace). The combined use of oxygen absorbers and flexible oxygen barrier film gave excellent retention of β‐carotene during the 210 day trial.}, number={1}, journal={JOURNAL OF FOOD QUALITY}, author={Emenhiser, C and Watkins, RH and Simunovic, N and Solomons, N and Bulux, J and Barrows, J and Schwartz, SJ}, year={1999}, month={Mar}, pages={63–73} } @article{numfor_walter_schwartz_1998, title={Emulsifiers affect the texture of pastes made from fermented and non-fermented cassava flours}, volume={33}, DOI={10.1046/j.1365-2621.1998.00194.x}, abstractNote={The effects of glycerol monostearate (GMS) and sodium steroyl lactylate (SSL) on the rheological properties of native, naturally fermented (NF) and mixed culture fermented (MCF) cassava flour pastes were measured using instrumental texture profile analysis (TPA) and by finger cohesiveness (difficulty in separation). Fermentation reduced the TPA parameters, hardness, cohesiveness and gumminess, but not springiness/elasticity. These were reduced further when either GMS or SSL were incorporated into the pastes. Pastes made from native and naturally fermented flours were scored by a Cameroonian sensory panel as difficult to separate, whereas scores for native and fermented flour pastes treated with 1% or more of GMS or SSL were easy to separate. Increased internal stability of the cassava flour starch granules was suggested as the cause of the effects.}, number={5}, journal={International Journal of Food Science and Technology}, author={Numfor, F. A. and Walter, W. M. and Schwartz, S. J.}, year={1998}, pages={455–460} } @article{henry_catignani_schwartz_1998, title={Oxidative degradation kinetics of lycopene, lutein, and 9-cis and all-trans beta-carotenee}, volume={75}, ISSN={["0003-021X"]}, DOI={10.1007/s11746-998-0232-3}, abstractNote={AbstractThe thermal and oxidative degradation of carotenoids was studied in an oil model system to determine their relative stabilities and the major β‐carotene isomers formed during the reaction. All‐trans β‐carotene, 9‐cis β‐carotene, lycopene, and lutein were heated in safflower seed oil at 75, 85, and 95°C for 24, 12, and 5 h, respectively. The major isomers formed during heating of β‐carotene were 13‐cis, 9‐cis, and an unidentified cis isomer. The degradation kinetics for the carotenoids followed a first‐order kinetic model. The rates of degradation were as follows: lycopene>all‐trans β‐carotene≈9‐cis β‐carotene>lutein. The values for the thermodynamic parameters indicate that a kinetic compensation effect exists between all of the carotenoids. These data suggest that lycopene was most susceptible to degradation and lutein had the greatest stability in the model system of the carotenoids tested. Furthermore, there was no significant difference in the rates of degradation for 9‐cis and all‐trans β‐carotene under the experimental conditions.}, number={7}, journal={JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY}, author={Henry, LK and Catignani, G and Schwartz, S}, year={1998}, month={Jul}, pages={823–829} } @article{henry_catignani_schwartz_1998, title={The influence of carotenoids and tocopherols on the stability of safflower seed oil during heat-catalyzed oxidation}, volume={75}, ISSN={["0003-021X"]}, DOI={10.1007/s11746-998-0189-2}, abstractNote={AbstractThe stability and antioxidant effects of carotenoids and tocopherols in safflower seed oil were evaluated under thermal (75°C) and oxidative conditions and the oxidative stability index (OSI) determined. The antioxidant capability of butylated hydroxytoluene (BHT) was also compared with that of β‐carotene in a model system. Lycopene and β‐carotene (1 to 2000 ppm) were heated (75°C) and exposed to air (2.5 psi) in an oxidative stability instrument. β‐Carotene had no antioxidant effect at concentrations below 500 ppm, because it did not alter the induction time. Lycopene increased the induction time only slightly at low concentrations. However, at concentrations greater than 500 ppm, both β‐carotene and lycopene acted as prooxidants, significantly decreasing the induction period. At the highest concentration, 2000 ppm, lycopene was more prooxidative than β‐carotene. α‐ and γ‐Tocopherol (concentration, 1000 ppm) delayed the induction time by 16 and 26 h, respectively. There was no cooperative interaction between α‐tocopherol and β‐carotene in delaying the onset of oxidation. Furthermore, BHT was significantly more antioxidative than β‐carotene. Thus, under thermal and oxidative conditions, β‐carotene could not delay the onset of oxidation. The tocopherols and BHT were effective in suppressing the onset of oxidation, as determined by the oxidative stability measurement.}, number={10}, journal={JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY}, author={Henry, LK and Catignani, GL and Schwartz, SJ}, year={1998}, month={Oct}, pages={1399–1402} } @article{lessin_catigani_schwartz_1997, title={Quantification of cis-trans isomers of provitamin A carotenoids in fresh and processed fruits and vegetables}, volume={45}, ISSN={["0021-8561"]}, DOI={10.1021/jf960803z}, abstractNote={A polymeric 5 μm C30 stationary phase for reversed phase HPLC was used to separate and quantitate geometric isomers of provitamin A carotenoids in fresh and processed fruits and vegetables. β-Carotene isomers (all-trans, 9-cis, 13-cis, and 15-cis), α-carotene isomers (all-trans, 9-cis, 13-cis, and 13‘-cis), and β-cryptoxanthin isomers (all-trans, 13 and 13‘-cis, and 15-cis) were resolved isocratically using the C30 stationary phase with 89:11 methanol/methyl tert-butyl ether as mobile phase. The percent of cis isomers increased 10−39% with canning. The total provitamin A carotenoid content (in micrograms per gram of dry weight of tissue) ranged from 3.5 to 907 in fresh samples and from 1.8 to 1055 in canned samples. In several fruits and vegetables, processing produced an increase of 16−50% of total measured provitamin A carotenoids relative to the fresh samples. These increases were most likely a result of increased extraction efficiency, inactivation of enzymes capable of degrading carotenoids, and/or l...}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Lessin, WJ and Catigani, GL and Schwartz, SJ}, year={1997}, month={Oct}, pages={3728–3732} }