ESTABILIDADES QUÍMICA, FÍSICO-QUÍMICA E MICROBIOLÓGICA DE SUCO DE LARANJA cv. “PERA” SUBMETIDO A DIFERENTES CONDIÇÕES DE ESTOCAGEM

Abstract

CHEMICAL, PHYSICO-CHEMICAL AND MICROBIOLOGICAL STABILITY OF ORANGE JUICE, cv. "PERA", IN DIFFERENT STORAGE CONDITIONS This study aimed to evaluate chemical, physicochemical and microbiological stabilities of orange juice,cv. "Pera", kept at room temperature, under refrigeration or freezing for different storage periods. Ascorbic acid and total soluble solids content, total titratable acidity and pH were determined. Mesophilic bacteria, yeasts and moulds, lactic bacteria, total and fecal coliforms and Salmonella were subject to microbiological count. Ascorbic acid content and total soluble solids remained stable in all storage conditions. The same was observed for total titratable acidity and pH in most samples, except for frozen orange juice, in which these parameters varied from the 120 th day to the end. Salmonella spp., total and fecal coliforms were not found in any samples. The initial count of mesophilic bacteria, yeasts and moulds, and lactic bacteria were around 3 Log CFU/mL. In the juice stored at room temperature during 24 hours,an increase of 1.5, 2.3 and 3.4 Log CFU/mL in the count of mesophilic bacteria, yeasts and moulds and lactic bacteria, respectively, was observed. In the juices kept under refrigeration the microbiological count did not exceed the initial one until the fourth day. In juices kept under freezing, the microbiological count remained lower than the initial one for 180 days. According to these results, in natura orange juice preserved its quality when stored under refrigeration for 48h or under freezing during 120 days. KEY-WORDS: CHEMICAL STABILITY; MICROBIOLOGICAL STABILITY; ORANGE JUICE. REFERÊNCIAS 1 ALMEIDA C.A.N.; CROTT G.C.; RICCO R.G.; DEL CIAMPO L.A.; DUTRA-DE-OLIVEIRA J.E.; CANTOLINI A. Control of iron-deficiency anaemia in Brazilian preschool children using iron-fortified orange juice.

Changes in bioactive compounds and antioxidant capacity of fresh-cut cashew apple

“…After cutting, a decrease on ascorbic acid content, from 12% to 38% was observed, in all storage temperatures, showing its high sensitivity to oxygen. Lavinas et al (2006) observed reduction of around 5% on ascorbic acid in cashew apple juice stored at 2°C and 23°C for 24 h, while Silva et al (2007) did not observe modifications on ascorbic acid content in orange juice stored at 4°C and 23°C for 24 h. These differences may be due to larger surface available for oxygen contact when cashew apples were stored cut in pieces than as juice. Stability of ascorbic acid can change depending on the fruit pH, since low pH protects this compound from oxidation.…”

“…Stability of ascorbic acid can change depending on the fruit pH, since low pH protects this compound from oxidation. The pH of orange juice was 3.3, while the cashew apple juice was 4.3 (Silva et al, 2007;Lavinas et al, 2006). Ascorbic acid content was lower at higher temperatures, but no significant difference was observed between 27°C and 40°C.…”

Estudo da estabilidade quÍmica e microbiológica do suco de caju in natura armazenado em diferentes condições de estocagem

“…3 -rEsultados E discussÃo 3.1 -Validação do método titulométrico para suco de caju in natura A determinação de AA em sucos de frutas por titulação com 2,6-diclorofenolindofenol é a metodologia recomendada pela Associação Oficial de Análises Químicas [6] e existem vários trabalhos publicados que empregam esta metodologia para determinar o teor desta vitamina em sucos de frutas [4,7,12,20,28,31,33,43].…”

“…Os resultados de teor de AA em sucos de diferentes frutas demonstram que, comparativamente, o suco de caju apresenta teor mais elevado desta vitamina [1,30,41,43,49]. Desta forma, é possível confirmar que o suco de caju é uma importante fonte de AA, apresentando teores superiores aos dos outros sucos considerados como fontes desta vitamina, como os de laranja e limão.…”

Avaliação Microbiológica Do Suco De Laranja in Natura Comercializado Em via Pública Na Zona Central De São Paulo-Sp

“…Sendo fonte de vitamina C e considerada um potente e efetivo antioxidante, mesmo se ingerida em pequenas quantidades. Além disso, seu consumo está relacionado com a prevenção de danos oxidativos e de determinadas enfermidades, como o escorbuto (FIGUEIREDO, 2009;DOLINSKY, 2011;SILVA et al, 2007).…”