Marilú Andrea Silva-Espinoza1, Ana Salvador2, María Del Mar Camacho1, Nuria Martínez-Navarrete1. 1. Food Technology Department, Food Investigation and Innovation Group, Universitat Politècnica de València, Valencia, Spain. 2. Laboratorio de Propiedades Físicas y Sensoriales y Ciencia del Consumidor, Instituto de Agroquímica y Tecnología de Alimentos (CSIC), Valencia, Spain.
Abstract
BACKGROUND: The health benefits provided by fruit mean that there is continuous interest in offering consumers new products to stimulate its consumption. To this end, dehydrated fruit snacks may be an interesting option. In this study, we evaluated the impact of freezing rate (slow and high), shelf temperature (40 and 50 °C), and working pressure (5 and 100 Pa) on the perception and acceptability of a freeze-dried orange snack obtained from an orange puree. RESULTS: Of the different freeze-drying conditions studied, working pressure was the variable with the greatest effect. The lowest working pressure (5 Pa) led to samples being obtained with a slightly lower water content, which was perceived with higher citrus flavor and crispiest. The highest pressure (100 Pa) led to samples with a greater water content, perceived with a more yellow intense color. Nevertheless, there is no significant consumer preference for any of the different processed samples. The number of force peaks, which is positively correlated with the crispness, shows a significant and negative correlation (r = -0.91) with the water content of the sample. CONCLUSION: The study revealed that considerations other than the sensory can determine the best conditions of the freeze-drying process with which to obtain an orange snack. The number of force peaks obtained from a penetration test may be proposed as a tool for instrumental analysis of the snack's crispness that supplies information closely resembling customer perception of this attribute.
BACKGROUND: The health benefits provided by fruit mean that there is continuous interest in offering consumers new products to stimulate its consumption. To this end, dehydrated fruit snacks may be an interesting option. In this study, we evaluated the impact of freezing rate (slow and high), shelf temperature (40 and 50 °C), and working pressure (5 and 100 Pa) on the perception and acceptability of a freeze-dried orange snack obtained from an orange puree. RESULTS: Of the different freeze-drying conditions studied, working pressure was the variable with the greatest effect. The lowest working pressure (5 Pa) led to samples being obtained with a slightly lower water content, which was perceived with higher citrus flavor and crispiest. The highest pressure (100 Pa) led to samples with a greater water content, perceived with a more yellow intense color. Nevertheless, there is no significant consumer preference for any of the different processed samples. The number of force peaks, which is positively correlated with the crispness, shows a significant and negative correlation (r = -0.91) with the water content of the sample. CONCLUSION: The study revealed that considerations other than the sensory can determine the best conditions of the freeze-drying process with which to obtain an orange snack. The number of force peaks obtained from a penetration test may be proposed as a tool for instrumental analysis of the snack's crispness that supplies information closely resembling customer perception of this attribute.