RESUMEN
A storage trial was conducted to observe the effect of typical northern Australia climatic conditions on a military ration chocolate (RC). The results indicate that sensory quality decreased during storage; after seven days the chocolate was no longer of acceptable appearance. Deterioration in RC sensory quality was strongly correlated with decreases in visual acceptance (appearance) and increases in degree of blooming. Instrumental colour measurements were also strongly correlated with sensory ratings. Visual and microscopic observations provide evidence for movement of fat to and across the surface of the RC, behaviour that may be explained in terms of the phase transition theory of fat blooming. DSC thermographs provide evidence of a shift from predominantly polymorph form V in a fresh RC sample to a greater proportion of form VI in bloomed storage samples. The study provides a baseline against which efforts to improve the quality of RC may be evaluated.
Asunto(s)
Cacao/química , Grasas/química , Almacenamiento de Alimentos/métodos , Gusto , Australia , Color , Manipulación de Alimentos , HumanosRESUMEN
Asian noodles are a major end use of common wheat flour globally. A microbiological assay protocol for the folate contents of flour and Asian noodles has been developed. Different approaches were compared for enzymatic extraction and deconjugation of folate following the establishment of optimum inoculum concentration for analysis. The folate results obtained varied when samples were subjected to different preparation and extraction procedures. The use of trienzyme treatments gave significantly higher content values. The pH and specific conditions of enzyme treatment also influenced the results. In applying well-established methods for folate analysis, it is essential to consider extraction procedures effective for the specific food products being analyzed. A suitable, validated method was developed and is recommended for use in further studies of fortification of wheat flour for Asian noodle processing.
Asunto(s)
Harina/análisis , Ácido Fólico/aislamiento & purificación , Análisis de los Alimentos , Alimentos Fortificados/análisis , Lacticaseibacillus casei/enzimología , Animales , Pollos , Recuento de Colonia Microbiana , Criopreservación/métodos , Ácido Fólico/análisis , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Análisis de los Alimentos/normas , Lacticaseibacillus casei/crecimiento & desarrollo , Péptido Hidrolasas/metabolismo , Péptido Hidrolasas/farmacología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría/métodos , Espectrofotometría/normas , alfa-Amilasas/metabolismo , alfa-Amilasas/farmacologíaRESUMEN
The folate contents of 26 commercial noodle samples were investigated. The impact of ingredients, pH, and cooking on folate content was studied for the 3 predominant styles of noodles: white salted, yellow alkaline, and instant. Some variability was found in the proportion of folate present in the free form and the noodles generally had low total folate contents. The pH values of the samples covered a wide range, varying from 3.7 to 10.3; however, the results did not provide strong evidence for a relationship between pH and folate content for any of the noodle styles studied. Higher folate levels were typically found in yellow alkaline samples compared to white salted and instant noodles. The storage of noodles in dry or moist forms did not appear to influence total folate contents, and subsequent losses during cooking depended upon the time of exposure to elevated temperatures. The enzymatic treatment of samples was particularly important for cooked noodles, indicating that folates were bound or entrapped during this process.
Asunto(s)
Culinaria/métodos , Harina/análisis , Ácido Fólico/aislamiento & purificación , Estabilidad de Medicamentos , Ácido Fólico/química , Tecnología de Alimentos , Alimentos Fortificados , Concentración de Iones de HidrógenoRESUMEN
Asian noodles, a widely consumed staple food, were evaluated as potential vehicles for fortification with folic acid. Samples of white salted, yellow alkaline, and instant noodles, prepared under controlled laboratory conditions, were fortified and folates were measured at each stage of processing using a microbiological assay. Although the 3 styles showed differing patterns of retention, overall losses were slightly more than 40% and were similar for all styles. White salted and yellow alkaline noodles showed no significant decrease in total folate content during production. In contrast, significant losses occurred for instant noodles during steaming and deep-frying of the noodle strands. In all cases, substantial losses occurred during subsequent cooking of the dried noodles. Fortification at a rate of 50% of the reference value per serving resulted in retention of folate at levels corresponding to 30% following cooking, whereas unfortified noodles contributed less than 4% per serving. It is concluded that fortifying Asian noodles provides an effective means for enhancing folate intake.