This project will end at the end of October, 2021,so this is the second to last report. There are two objectives in this
project, and the progress of each objective is listed here:Objective 1. Evaluation of blended juice using released
HLB-tolerant sweet orange/mandarin cultivars via analyses of sensory and consumer acceptance. In this quarter, we did
the sensory and consumer study for Valencia blended with Sugar Belle at the end of May. In this study, 100% Sugar
Belle® juice, 100% Valencia juice, 90% Valencia and 10% Sugar Belle® blended juice, 50% Valencia and 50% Sugar
Belle® blended juice, and the same 100% commercial NFC orange juice product were prepared and consumed by 61
sensory panelists. Panelists were pre-screened based on their orange juice consumption frequency to ensure they are
familiar with orange juice. Compared to 100% commercial NFC orange juice, 50% Valencia and 50% Sugar Belle®
blended juice was rated significantly higher in overall appearance, overall liking and flavor liking. In the subsequent
evaluation on sensory attributes (i.e. sweetness, bitterness and sourness etc.) that are closely related to fruit quality, 50/50
and 90/10 blended juices received higher ratings on sweetness, lower ratings on sourness and bitterness, which indicated
Valencia orange juice blended with Sugar Belle® increased the consumer preference. In addition, from the sensory
aspect, 90/10 Valencia/Sugar Belle® blended juice were preferred the most by consumers. Surprisingly, when panelists
were asked their general opinion on their willingness-to-pay of 100% orange juice and mandarin and orange blended juice
without tasting any specific samples, it was observed that they expected to pay higher price for juice containing higher
ratio of orange juice. For example, the 100% orange juice receiving the most votes on $3.49 per 52 FL oz. More
information will be collected in the next quarter to explain the mismatch between willingness-to-pay expectation for known
ratio of orange juice in blended juices and the results obtained from the real tasting environment. Even though the
acceptance of tangerine juice is currently limited, it was noteworthy that the Valencia orange juice and Sugar Belle® juice
blends had a better performance in sensory evaluation than that of pure orange juice. In addition, there were considerable
number of consumers holding neutral opinion on juice quality and willingness-to-pay of blended orange and mandarin juice
indicating the potential improvement on acceptance and consumption of mandarin juice in the future. We wrote an article
for the Citrus Industry and this article will be published in September based on our findings from this quarter and the
previous quarters. Objective 2. Identify more tolerant cultivars resembling the quality of Valencia for the juice market, and
identify a chemistry definition of consumer accepted orange flavor. All the analytical work has been completed in the last
quarter, so in this quarter we focused on data analysis and writing a manuscript. We investigated citrus fruit flavor and
identify key flavor compounds in a diverse group of citrus fruits through multivariate statistical analysis. Volatile and
non-volatile chemicals were determined by MS spectrometric techniques while the rating of sensory attributes was
collected from a trained sensory panel. The results of Pearson Correlation showed the extent of positive/negative
correlation between the sweet attribute and other sensory attributes in different groups of citrus fruits. Based on the
correlation between chemicals and sensory attributes, sugars were highly correlated with the sweet attribute while
flavonoids and limonoids were highly correlated with the bitter attribute. Organic acids showed a strong correlation with the
sour attribute and demonstrated contribution to the citrusy attribute. Terpenes were highly associated with the terpene-like
attribute while octanal, decanal, ethyl hexanoate and ethyl octanoate were demonstrated to be highly correlated with the
citrusy attribute. The correlations between linalool, citronellol, and 1-octanol and the fruity/floral attribute were also
observed. In addition, pathway enrichment analysis demonstrated a close correlation between the biosynthesis of
terpenoids and steroids pathway and the identified key flavor compounds in sweet orange-like mandarin hybrids.