Dimensionamento amostral para frutos de mamoeiro ‘Golden THB’ destinados ao mercado nacional e à exportação

Abstract

Resumo: Considerando que o tamanho de amostras é importante para a caracterização de lotes de frutas, objetivou-se com este trabalho determinar o tamanho mínimo necessário de amostra para caracterizar frutos comerciais de mamoeiro 'Golden THB' destinados ao mercado nacional e à exportação, antes e após armazenamento. O trabalho foi aplicado a 300 frutos separadamente, sendo 150 destinados ao mercado nacional e 150 à exportação. Para o mercado nacional, as avaliações iniciaram com 75 frutos logo após os tratamentos pós-colheitas em casa de embalagem (antes da armazenagem), e a outra feita após 5 dias de armazenagem a temperatura ambiente. Para os frutos destinados à exportação, as análises foram feitas antes da armazenagem, e a outra aos 14 dias de armazenagem em câmara frigorífica, regulada em 9 °C. As características avaliadas foram: massa do fruto; comprimento do fruto; largura do fruto; a relação entre comprimento e largura do fruto; firmeza; teor de sólidos solúveis totais; acidez total titulável e ratio. Em seguida, foi calculado o tamanho da amostra aplicando o método determinístico a partir da semi-amplitude do intervalo de confiança. O tamanho de amostra para a mensuração de frutos de mamoeiro 'Golden THB' varia com a característica, a destinação do produto e o armazenamento. Para o mercado nacional e após armazenamento, a amostragem requer maior número de frutos para as características físicas. Para a característica de firmeza, com 10% de erro em torno da média, o tamanho de amostra é de 988 e 117 frutos, após armazenamento, para o mercado nacional e exportação, respectivamente. Para todas as outras características, 31 frutos são suficientes para a caracterização, com erro de 10% em torno da média. Palavras-chave: Carica papaya L. Método determinístico. Variabilidade.Abstract: Considering that sample size is important for the characterisation of fruit lots, the aim of this study was to determine the minimum sample size necessary to characterise commercial fruits of the 'Golden THB' papaya, for the domestic market and for export, before and after storage. Three hundred fruit were studied separately, of which 150 were destined for the domestic market and 150 for export. For the domestic market, evaluations began with 75 fruit shortly after post-harvest treatment at the packing house (before storage), and the other after 5 days of storage at room temperature. For the fruits destined for export, analysis was carried out before storage and the other after 14 days of storage in a cold room, set at 9°C. The characteristics under evaluation were: fruit weight; fruit length; fruit width; the ratio of fruit length to fruit width; firmness; total soluble solids; total titratable acidity and ratio. The sample size was then calculated by deterministic method, from the half-amplitude of the confidence interval. The sample size for measuring fruit of the 'Golden THB' papaya varies with the characteristic, destination and storage. For the domestic market and after storage, sampling requires a greater number of fruit fo...

Sample size for the evaluation of ‘BH-65’ papaya fruits under protected cultivation

“…Thus, to evaluate the weight of fruits, with a 5% error, sample should be made of 223 and 55 fruits, respectively, for July and March harvests. As expected, sample size decreases when the error allowed around the average increases (for instance from 5 to 10%) (RESENDE, 2007;TOEBE et al, 2014a;SILVA et al, 2017). Thus, if the researcher wants to evaluate fruit weight considering a 10% error around the average, only 56 and 14 fruits are needed, for July and March harvests, respectively.…”

“…Characteristics demanding smaller sample sizes were fruit length and diameter, total soluble solids content and skin and pulp color attributes L* and h. To evaluate the average length of fruits, with a 10% error around the average, it was necessary to evaluate 7 fruits in harvest carried out in July and only 3 in March. Fruit length and diameter were also the parameters that required smaller sample size to evaluate pineapple fruits (KRAUSE et al, 2013), plum (SILVA et al, 2016 and 'Golden THB' papaya (SILVA et al, 2017).…”

“…The sample size to evaluate fruits is influenced by several factors, among them, the intrinsic variability of fruits, physical or chemical (SCHMILDT et al, 2017), the maturation stage (SILVA et al, 2017), harvest date (TONINI, 2013) and sample precision defined by the researcher (KRYSCZUN et al, 2018). According to Krysczun et al (2018), factors that lead to variability of experimental error interfere in the statistics of hypotheses tests and in the comparison of treatments, leading to erroneous interpretations and conclusions (KRYSCZUN et al, 2018).…”

“…Several studies show the adequate sample size to describe fruit characteristics in several crops as Citrus sinensis (AVANZA et al, 2010), Passiflora spp. (COELHO et al, 2011;BANDEIRA et al, 2016;, Prunus persica (TOEBE et al, 2012), Litchi chinensis (ANDRADE and JASPER, 2012), Ananas comosus (KRAUSE et al, 2013), Bertholletia excelsa (BORGES et al, 2016), Carica papaya (FERREIRA, 2014;SILVA et al, 2017), Malus domestica (TOEBE et al, 2014a), Carya illinoinensis (CARGNELUTTI FILHO et al, 2015;POLETTO et al, 2018), and Spondias purpurea (SILVA et al, 2016).…”

“…In papaya, different studies using fruits of 'Golden THB' establish sample size for fruits harvested in the field (Ferreira, 2014), and for fruits subjected to a postharvest treatment (Silva et al, 2017). However, there are no reports about the correct sample size for papaya fruits produced under protected cultivation, despite the importance acquired in recent years (MARTELLETO et al, 2011;PRAKASH et al, 2015;SALINAS et al, 2017SALINAS et al, , 2018.…”