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The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (<75 mg/L) nitrogen content, and four enological yeast strains, were used in cider fermentation. The aspartic acid, asparagine and glutamic acid amino acids were the majority in all the apple juices, representing 57.10% to 81.95%. These three amino acids provided a high consumption (>90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3-methyl-1-butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation.

The aim of this study was to identify the main amino acids responsible for the production of esters in ciders. The experiments were carried out in apple must and synthetic must. The amino acids were analysed by high‐performance liquid chromatography and the volatile compounds by gas chromatography. Aspartate, asparagine and glutamate positively influenced the production of esters in the cider models and were used in the experiments with mixtures. The response surface generated by the proposed model yielded two regions that maximized the production of esters. In addition, the combination of aspartate and glutamate predicted a higher production. The optimal suggested concentrations were 43.4% of aspartate and 56.6% of glutamate for 120 mg/L of total nitrogen. The apple must supplemented with these two amino acids resulted in four times more esters than in the same cider without supplementation, demonstrating the effectiveness of the proposed model.

This study aims to evaluate the aromatic profile of fermented apple, obtained by the action of strains of Hanseniaspora uvarum and Hanseniaspora guilliermondii using two methods of analysis: static headspace and solid phase microextraction (SPME). The results obtained confirm that the strains of the Hanseniaspora genus contributed positively to the aroma profile of fermented apple, producing considerable amounts of esters and higher alcohols. In comparing the methods of analysis of aromatic compounds using headspace and SPME, it was verified that by using the headspace method it was possible to capture amounts that were up to 16 times greater than the value of the volatile compounds obtained by SPME. However, when using SPME, 5 times more compounds were obtained than when using headspace. Even so, in the conditions of this study it was noted that headspace was more efficient in the extraction of the aromatics of fermented apple when taking into consideration the cost effectiveness of both methods.

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Uma importante função da embalagem nos alimentos é a conservação do produto. Quando se trata de frutas, essa função é determinante já que os atributos visuais de qualidade (aparência e cor) são limitantes no momento da compra, e sofrem transformações rápidas após a colheita. Neste trabalho objetivou-se avaliar o efeito de diferentes embalagens (tereftalato de polietileno, embalagem ativa e biofilme de pectina) na conservação de morangos. As frutas foram lavadas e sanitizadas com hipoclorito de sódio, e posteriormente envolvidas pelas embalagens. Foi realizado um delineamento experimental 32, sendo que os fatores foram o tipo de embalagem e o tempo de armazenamento (3, 5 e 7 dias). Foram avaliados os parâmetros colorimétricos (L*, a* e b*), a perda de massa, o teor de sólidos solúveis e pH durante os períodos de armazenamento. O biofilme de pectina resultou em maiores variações do peso (29,03%), porém manteve as menores variações nos demais parâmetros avaliados. O fator tempo foi significativo (P ≤ 0,05) apenas para as respostas a* e b* da cor. Os resultados deste trabalho demonstram uma alternativa para melhorar a conservação dos morangos.

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